C165H
Embedded C166 with
USART, IOM-2 and
HDLC Support
Version 1.3
Data Sheet, DS 1, April 2001
Wired
Communications
Never stop thinking.
Edition 2001-04-01
Published by Infineon Technologies AG,
St.-Martin-Strasse 53,
D-81541 München, Germany
© Infineon Technologies AG 2001.
All Rights Reserved.
Attention please!
The information herein is given to describe certain components and shall not be considered as warranted
characteristics.
Terms of delivery and rights to technical change reserved.
We hereby disclaim any and all warranties, including but not limited to warranties of non-infringement, regarding
circuits, descriptions and charts stated herein.
Infineon Technologies is an approved CECC manufacturer.
Information
For further information on technology, delivery terms and conditions and prices please contact your nearest
Infineon Technologies Office in Germany or our Infineon Technologies Representatives worldwide (see address
list).
Warnings
Due to technical requirements components may contain dangerous substances. For information on the types in
question please contact your nearest Infineon Technologies Office.
Infineon Technologies Components may only be used in life-support devices or systems with the express written
approval of Infineon Technologies, if a failure of such components can reasonably be expected to cause the failure
of that life-support device or system, or to affect the safety or effectiveness of that device or system. Life support
devices or systems are intended to be implanted in the human body, or to support and/or maintain and sustain
and/or protect human life. If they fail, it is reasonable to assume that the health of the user or other persons may
be endangered.
Wired
Communications
C165H
Embedded C166 with
USART, IOM-2 and
HDLC Support
Version 1.3
Data Sheet, DS 1, April 2001
Never stop thinking.
For questions on technology, delivery and prices please contact the Infineon
Technologies Offices in Germany or the Infineon Technologies Companies and
Representatives worldwide: see our webpage at http://www.infineon.com
C165H
Revision History: 2001-04-01 DS 1
Previous Version: This is the first non-preliminary version. 1)
1)All previous distributed versions are preliminary. They have been replaced by this version.
Page Subjects (major changes since last revision)
C165H
Page
Data Sheet 2001-04-19
Table of Contents
1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
1.1 Key Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
1.2 Logic Symbol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
1.3 Pinning Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
1.4 Typical Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
1.4.1 ISDN NT and PBX Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
2 Pin Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2.1 C165H Pin Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2.2 C165H Pin Definitions and Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3 Architectural Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
3.1 Basic CPU Concepts and Optimizations . . . . . . . . . . . . . . . . . . . . . . . . . . 29
3.2 On-Chip System Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
3.3 Clock Generation Concept . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
3.4 On-Chip Peripheral Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
3.5 Protected Bits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
4 Memory Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
4.1 Internal RAM and SFR Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
4.2 External Memory Space . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
4.3 Crossing Memory Boundaries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
5 Central Processor Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
5.1 Instruction Pipelining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
5.2 Bit-Handling and Bit-Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
5.3 Instruction State Times . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
5.4 CPU Special Function Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
5.5 PEC - Extension of Functionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
6 Interrupt and Trap Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
6.1 Interrupt System Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
6.2 Interrupt Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
6.3 Operation of the PEC Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
6.4 Prioritization of Interrupt and PEC Service Requests . . . . . . . . . . . . . . . 105
6.5 Saving the Status during Interrupt Service . . . . . . . . . . . . . . . . . . . . . . . 108
6.6 Interrupt Response Times . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
6.7 PEC Response Times . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
6.8 External Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
6.8.1 Fast External Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
6.8.2 External Interrupt Source Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
6.8.3 Interrupt Subnode Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
6.8.4 The Interrupt Control Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
6.9 Trap Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
C165H
Page
Data Sheet 2001-04-19
Table of Contents
7 Parallel Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
7.1 PORT0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
7.1.1 Alternate Functions of PORT0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
7.2 PORT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
7.2.1 Alternate Functions of PORT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138
7.3 PORT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
7.3.1 Alternate Functions of PORT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
7.4 PORT3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144
7.4.1 Alternate Functions of PORT3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147
7.5 PORT4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150
7.5.1 Alternate Functions of PORT4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153
7.6 PORT6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154
7.6.1 Alternate Functions of PORT6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
7.7 PORT7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160
8 Dedicated Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163
9 External Bus Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166
9.1 External Bus Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167
9.2 Programmable Bus Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
9.3 READY Controlled Bus Cycles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181
9.4 Controlling the External Bus Controller . . . . . . . . . . . . . . . . . . . . . . . . . . 183
9.5 EBC Idle State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194
9.6 External Bus Arbitration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194
9.7 XBUS Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198
9.8 Initialization of the C165H’s X-peripherals . . . . . . . . . . . . . . . . . . . . . . . . 199
10 General Purpose Timer Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200
10.1 Kernel Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201
10.1.1 Functional Description of Timer Block 1 . . . . . . . . . . . . . . . . . . . . . . . 201
10.1.1.1 Core Timer T3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202
10.1.1.2 Auxiliary Timers T2 and T4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211
10.1.1.3 Timer Concatenation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
10.1.2 Functional Description of Timer Block 2 . . . . . . . . . . . . . . . . . . . . . . . 218
10.1.2.1 Core Timer T6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 219
10.1.2.2 Auxiliary Timer T5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221
10.1.2.3 Timer Concatenation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223
10.1.3 GPT Register Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224
11 Asynchronous/Synchr. Serial Interface . . . . . . . . . . . . . . . . . . . . . . . . 238
11.1 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238
11.1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238
11.1.2 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240
11.1.3 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241
11.1.4 General Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252
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Data Sheet 2001-04-19
Table of Contents
11.1.5 Asynchronous Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253
11.1.5.1 Asynchronous Data Frames . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 255
11.1.5.2 Asynchronous Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257
11.1.5.3 Asynchronous Reception . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257
11.1.5.4 IrDA Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258
11.1.5.5 RXD/TXD Data Path Selection in Asynchronous Modes . . . . . . . . . 259
11.1.6 Synchronous Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260
11.1.6.1 Synchronous Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261
11.1.6.2 Synchronous Reception . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262
11.1.6.3 Synchronous Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262
11.1.7 Baudrate Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263
11.1.7.1 Baudrates in Asynchronous Mode . . . . . . . . . . . . . . . . . . . . . . . . . . 264
11.1.7.2 Baudrates in Synchronous Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . 267
11.1.8 Autobaud Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269
11.1.8.1 General Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269
11.1.8.2 Serial Frames for Autobaud Detection . . . . . . . . . . . . . . . . . . . . . . . 270
11.1.8.3 Baudrate Selection and Calculation . . . . . . . . . . . . . . . . . . . . . . . . . 272
11.1.8.4 Overwriting Registers on Successful Autobaud Detection . . . . . . . 274
11.1.9 Hardware Error Detection Capabilities . . . . . . . . . . . . . . . . . . . . . . . . 275
11.1.10 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 276
12 Real Time Clock (RTC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278
12.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278
12.1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278
12.1.2 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278
12.2 Function Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278
12.2.1 RTC Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 279
12.2.2 RTC Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 280
12.2.3 System Clock Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 280
12.2.4 Cyclic Interrupt Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 280
12.2.5 Alarm Interrupt Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 280
12.2.6 48-bit Timer Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 281
12.2.7 Defining the RTC Time Base . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 281
12.2.8 Increased RTC Accuracy through Software Correction . . . . . . . . . . . . 283
12.2.9 Hardware dependend RTC Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . 283
12.2.10 Interrupt Sub Node RTCISNC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283
12.2.11 RTC Disable Functionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284
12.2.12 Register Definition of RTC module . . . . . . . . . . . . . . . . . . . . . . . . . . . 285
13 High-Speed Synchronous Serial Interface . . . . . . . . . . . . . . . . . . . . . 290
13.1 Full-Duplex Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295
13.2 Half Duplex Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 298
13.3 Baud Rate Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300
13.4 Error Detection Mechanisms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 301
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Table of Contents
13.5 SSC Interrupt Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303
14 IOM-2 Interface Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306
14.1 IOM-2 and PCM Frame Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306
14.1.1 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306
14.1.1.1 Frame Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306
14.1.1.2 HDLC Channels on the IOM-2: B1, B2, D1, D2 . . . . . . . . . . . . . . . . 307
14.1.2 PCM Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307
14.1.3 Terminal Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307
14.1.4 Linecard Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 309
14.2 IOM-2 Handler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 309
14.3 IOM-2 Monitor Handler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 311
14.3.1 Handshake Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 311
14.3.2 Abort Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315
14.3.3 MONITOR Interrupt Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 317
14.4 C/I Channel Handler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 318
14.4.1 C/I0 - Command/Indication 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 318
14.4.2 C/I1 - Command/Indication 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 318
14.4.3 CIC Interrupt Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 319
14.4.4 D-Channel Access Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 319
14.4.4.1 TIC Bus D-Channel Access Control for HDLC-2 Controller . . . . . . . 320
14.5 Controller Data Access Handler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 321
14.5.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322
14.5.2 Looping and Shifting Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323
14.5.3 Monitoring Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 325
14.5.4 Synchronous Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 326
14.6 Bus Activation / Deactivation (Power Down) . . . . . . . . . . . . . . . . . . . . . . 329
14.6.1 Deactivation Request, Downstream (C165H) to Upstream . . . . . . . . . 330
14.6.2 Deactivation, Upstream to Downstream (C165H) . . . . . . . . . . . . . . . . 331
14.6.3 Activation Request, Downstream (C165H) to Upstream . . . . . . . . . . . 331
14.6.4 Activation, Upstream to Downstream (C165H) . . . . . . . . . . . . . . . . . . 331
14.7 HDLC Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 332
14.7.1 Message Transfer Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 333
14.7.1.1 Non-Auto Mode (MDS2-0 = ’01x’) . . . . . . . . . . . . . . . . . . . . . . . . . . 333
14.7.1.2 Transparent Mode 0 (MDS2-0 = ’110’). . . . . . . . . . . . . . . . . . . . . . . 333
14.7.1.3 Transparent Mode 1 (MDS2-0 = ’111’). . . . . . . . . . . . . . . . . . . . . . . 333
14.7.1.4 Transparent Mode 2 (MDS2-0 = ’101’). . . . . . . . . . . . . . . . . . . . . . . 334
14.7.1.5 Extended Transparent Mode (MDS2-0 = ’100’). . . . . . . . . . . . . . . . 334
14.7.2 Data Reception . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 334
14.7.2.1 General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 334
14.7.2.2 Possible Error Conditions during Reception of Frames . . . . . . . . . . 335
14.7.2.3 Receive Frame Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 335
14.7.3 Data Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337
C165H
Page
Data Sheet 2001-04-19
Table of Contents
14.7.3.1 General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337
14.7.3.2 Possible Error Conditions during Transmission of Frames . . . . . . . 339
14.7.3.3 Transmit Frame Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 339
14.7.4 General Access to IOM-2 Channels . . . . . . . . . . . . . . . . . . . . . . . . . . 340
14.7.5 Extended Transparent Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 340
14.7.5.1 Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 341
14.7.5.2 Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 341
14.7.6 HDLC Controller Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 341
14.7.6.1 General HDLC Interrupt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 341
14.7.6.2 HDLC Transmit/Receive FIFO Interrupt . . . . . . . . . . . . . . . . . . . . . 342
14.7.6.3 Interrupt Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 343
14.8 IOM-2/HDLC Controller Register Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . 343
14.8.1 Register Description Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 343
14.8.2 Register Table ordered by Address . . . . . . . . . . . . . . . . . . . . . . . . . . . 344
14.8.3 Detailed Register Description ordered by Address . . . . . . . . . . . . . . . 349
14.8.4 HDLC-Channel Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 372
15 Watchdog Timer (WDT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 389
15.1 Operation of the Watchdog Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 390
16 Bootstrap Loader . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 393
17 System Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 398
17.1 System Startup Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 405
18 Power Reduction Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 410
18.1 Idle Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 410
18.2 Power Down Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 412
18.3 Status of Output Pins during Idle and Power Down Mode . . . . . . . . . . . . 412
18.4 Extended Power Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 414
18.4.1 Sleep Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 415
19 System Control Unit (CSCU) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 418
19.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 418
19.2 Operational Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 418
19.2.1 Overview of CSCU submodules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 418
19.3 XBUS Peripheral Configuration Block . . . . . . . . . . . . . . . . . . . . . . . . . . . 420
19.4 System Control Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 421
19.4.1 Register Write Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 421
19.4.2 Clock Output Frequency Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 425
19.5 Peripheral Management Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429
19.6 Identification Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 430
19.6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 430
19.6.2 ID Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 430
C165H
Page
Data Sheet 2001-04-19
Table of Contents
20 System Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 433
20.1 Stack Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 435
20.2 Register Banking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 440
20.3 Procedure Call Entry and Exit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 441
20.4 Table Searching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 443
20.5 Peripheral Control and Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 444
20.6 Floating Point Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 444
20.7 Trap/Interrupt Entry and Exit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 444
20.8 Unseparable Instruction Sequences . . . . . . . . . . . . . . . . . . . . . . . . . . . 445
20.9 Overriding the DPP Addressing Mechanism . . . . . . . . . . . . . . . . . . . . . 445
20.10 Pits, Traps and Mines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 447
21 Register Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 448
21.1 Register Description Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 448
21.2 CPU General Purpose Registers (GPRs) . . . . . . . . . . . . . . . . . . . . . . . . 449
21.3 Special Function Registers ordered by Address . . . . . . . . . . . . . . . . . . . 450
21.4 Special Function Registers ordered by Name . . . . . . . . . . . . . . . . . . . . . 458
21.5 Special Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 466
22 Instruction Set Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 467
23 AC/DC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 471
23.1 Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 471
23.2 Recommended Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . 471
23.3 DC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 471
23.4 Failsafe operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 473
23.5 Testing Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 474
23.6 AC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 474
23.6.1 Definition of Internal Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 475
23.6.2 System Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 476
23.6.3 External Clock Drive XTAL1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 477
23.6.4 IOM-2 Interface Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 478
23.6.5 JTAG Interface Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 480
23.7 Asynchronous Bus Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 481
23.7.1 Memory Cycle Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 481
23.7.1.1 AC Characteristics, Multiplexed Bus . . . . . . . . . . . . . . . . . . . . . . . . 481
23.7.1.2 AC Characteristics, Demultiplexed Bus . . . . . . . . . . . . . . . . . . . . . . 488
23.7.1.3 AC Characteristics, CLKOUT and READY . . . . . . . . . . . . . . . . . . . 495
24 Package Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 497
P-TQFP-144
Data Sheet 11 2001-04-19
Embedded C166 with USART, IOM-2 and HDLC
Support
C165H
C165H
Device Version 1.3 CMOS
Type Package
C165H P-TQFP-144
1 Overview
C165H is a new low cost member of the Infineon
Communication Controller family using low power
CMOS technology. The device combines the
successful Infineon C166 16-bit full-static core with
four independent HDLC controllers, IOM-2 interface
and 3-kbyte of Dual-Port on-chip RAM to a Intelligent
Terminal Adapter with HDLC support.
C165H adresses all high feature ISDN TA, Intelligent NT or SOHO PBX designs, offering
up to 18 MIPS along with legacy peripherals such as USART, SCI and Timers.
C165H provides:
•On-Chip full-static C166 Core supporting a 16- or 8-bit C16x Family System running
up to 36 MHz
•ISDN BRI supporting data rates of 56 kbit/s, 64 kbit/s, 128 kbit/s and 144 kbit/s
•IOM-2/PCM Interface
–Terminal Mode Type Interface to CODEC and S/U Transceiver
–Linecard Mode Type Interface up to 8 IOM-2 channels or 32 PCM channels
–1536/786 kHz and 1536 kHz...4096 kHz in 512 kHz steps
–Access to two Intercommunication channels (IC1, IC2)
–Access to two MON channels (MON0, MON1)
–Access to two C/I channels (CI0, CI1)
–S/G access support
•Four On-Chip Independent Full-Duplex HDLC Formatters
–8 independent 8-byte FIFOs for each transmit and receive channel
•USART Interface with AutoBaud Support (1,200 bit/s - 230,400 bit/s)
– AT-Command sensitive AutoBaud Detection
C165H
Overview
Data Sheet 12 2001-04-19
PRELIMINARY
- EXCERPT -
1.1 Key Features
C165H is a new low-cost member of the Infineon Communication Controller family. The
device has the following features:
•C166 Static Core with Peripherals including:
–Full-static core up to 18 MIPS (@36 MHz)
–Peripheral Event Controller (PEC) for 8 independent DMA channels
–16 Dynamically Programmable Priority-Level Interrupt System
–Eight External Interrupts
–Up to 72 SW-configurative Input/Output (I/O) Ports, some with Interrupt Capabilities
–8-bit or 16-bit External Data Bus
–Multiplexed or Demultiplexed Address/Data Bus
–Up to 8-Mbyte Linear Address Space for Code and Data
–Five Programmable Chip-Select Lines with Wait-State Generator Logic
–On-Chip 3,072-Byte Dual-Port SRAM for user applications
–On-Chip 1,024-Byte Special Function Register Area
–On-Chip PLL with Output Clock Signal
–Five Multimode General Purpose Timers
–On-Chip Programmable Watchdog Timer
–Glueless Interface to EPROM, Flash EPROM and SRAM
–Low-Power Management Supporting Idle-, Power-Down- and Sleep-Mode and
additional CPU clock slow-down mode with mode control for each peripheral
–USART interface with Auto Baud Rate detection up to 230.4 kbit/s
–USART Baud Rate generation in asynchronous mode up to 2.25 MBaud @ 36 MHz
–USART Baud Rate generation in synchronous mode up to 4.5 MBaud @ 36 MHz
–USART standard Baud Rates generation with very small deviation (230.4 kBaud
< 0.01%, 460.8 kBaud < 0.15 %, 691.2 kBaud < 0.04 %, 921.6 kBaud < 0.15 % ) @
36 MHz
–High speed Serial Synchronous Channel Interface (SSC) with ALIS-3.0 and AC97
compatibility up to 18 MBaud in SSC Master Mode and up to 9 MBaud in SSC Slave
Mode @ 36 MHz
•ISDN Terminal Adapter Features including:
–Four Independent Full-Duplex HDLC Controllers
–IOM-2/PCM interface supporting TE, LT and PCM mode
–MON and CI1/CI2-Handler
–Two D-Channels
–Two B-Channels Supported
–Concatenated 2B+D channel Support
–Two Intercommunication Channels IC1, IC2
–D-Channel Access Control to first IOM channel-0 by S/G bit
–CDA Channel Access to individual IOM-2/PCM channels by SW
C165H
Overview
Data Sheet 13 2001-04-19
PRELIMINARY
- EXCERPT -
•On-Chip PLL for CPU clock generation
•External crystal and direct driven input clock frequency can vary between 4 and 20
MHz dependent on the CPU target clock frequency.
•Single and variable crystal clock input frequency
•Bootstrap Loader support via USART interface
•On-Chip Debug Support (OCDS)
•JTAG Boundary Scan Test support according to IEEE 1149.1
•3.3 V single supply voltage
•5 V (TTL-) tolerant I/Os
•C165H is available in 144-Pin P-TQFP package
•Operating temperature range: -40°C to + 85°C.
C165H
Overview
Data Sheet 14 2001-04-19
PRELIMINARY
- EXCERPT -
Power Management
Besides the basic power-save (power-reduction) modes Idle mode and Power down
mode, the C165H offers a number of additional power management features, which can
be selectively used for effective power reduction. Refer to Table 1.
Note: Peripherals Management enables the user to control (via software) the clock of
selected peripherals. Refer to register SYSCON 3.
• C165H power requirement in individual modes is described in DC Characteristics,
Table 77
Table 1 Overview of Power Management Modes
Mode Description CPU Wake-up
Running
mode
The system is fully operational. All clocks and
peripherals are set and enabled, as determined
by software. Full power consumption.
----
Slow
down
mode
The CPU runs slower. The oscillator runs at a
lower frequency; the clock is divided by a
programmable factor (1...32). Peripherals
management is possible; incl. PLL On/Off.
Refer to register SYSCON 2.
Controlled by software.
Idle
mode
When the processor has no active tasks to
perform, it enters Idle mode by the IDLE
command. All peripherals remain powered and
clocked, however, peripherals management is
possible. For detailed description see
Chapter 18.1, "Idle Mode".
• Any interrupt
• Reset
Sleep
mode
The program stops execution and turns off the
clocks for:
• almost the entire chip, but RTC, or
• the entire chip.
The whole clock system is stopped.
Refer to register SYSCON 1.
• All enabled external
interrupts
•NMI
•RTC timer
(in asynchronous mode)
• PEC requests
• ASC interface
• SSC interface
Power
down
mode
The program stops execution (instruction
PWRDN) and turns off the clocks for the CPU
and for all peripherals; ports optionally.
• Reset
C165H
Overview
Data Sheet 16 2001-04-19
PRELIMINARY
- EXCERPT -
1.3 Pinning Diagram
Figure 2 shows the pinning diagram of the C165H.
Figure 2 Pinning Diagram of the C165H
unconnected
P0H.1
P0H.0
P0L.7
P0L.6
P0L.5
C165H
SAF C165H - LF
P-TQFP-144
108 73104 100 96 92 88 84 80 76
144
109
140
136
132
128
124
120
116
112
37
72
40
44
48
52
56
60
64
68
14 8 12162024283236
144-T_C165H
P0L.4
VSS
POL.3
POL.2
POL.1
P0L.0
VDD
VSS
ALE
VDD
VSS
P7.5
P7.4
P7.3
P7.2
P7.1
P7.0
VDD
VSS
P4.6
P4.5
P4.4
P4.3
P4.2
P4.1
VDD
WR / WRL
READY
EA
RD
unconnected
unconnected
TCK
TDI
TDO
TMS
VSS
VDD
DU
DD
DCL
FSC
CLKMODE
VSSA
XTAL1
XTAL2
VDDA
P3.3
P3.5
P3.6
P3.7
VSS
VDD
P3.8
P3.9
P3.10
P3.11
P3.12
P3.13
P3.15
P4.0
VSS
VDD
unconnected
BRKIN
BRKOUT
P6.4
VSS
VDD
P6.5
P6.6
P6.7
VSS
unconnected
unconnected
VDD
P2.0
P2.1
P2.2
P2.3
VSS
VDD
P2.4
P2.5
P2.6
P2.7
VSS
VDD
TEST
TRST
P1H.5
P1H.6
P1H.7
VSS
VDD
P6.0
P6.1
P6.2
P6.3
RSTIN
RSTOUT
NMI
P0H.4
P0H.5
P0H.6
P0H.7
VSS
VDD
P1L.0
P1L.1
P1L.2
P1L.3
VSS
VDD
P1L.4
P1L.5
P1L.6
P1L.7
VSS
VDD
P1H.0
P1H.1
P1H.2
P1H.3
P1H.4
VSS
VDD
unconnected
unconnected
unconnected
unconnected
unconnected
VSS
VDD
P0H.2
P0H.3
VSS
VDD
C165H
Overview
Data Sheet 17 2001-04-19
PRELIMINARY
- EXCERPT -
1.4 Typical Applications
1.4.1 ISDN NT and PBX Applications
C165H is designed to manage control message and data flow between the ISDN S/U
transceiver and a Personal Computer. Data and message transfer is possible between
either two of the following physical interfaces: IOM-2 interface or local memory via 16-bit
µP-interface. Since the IOM-2 is transparently accessible, additional IOM-2 devices such
as CODEC, Voice-Encrypter or Voice-Codec devices can be accessed e.g. via the
second IOM-2 channel (IC1/IC2).
Figure 3 gives a general overview of the ISDN NT/PBX application for C165H.
Figure 3 C165H in High Feature Intelligent Network Terminations
Note: In IOM-2 LT mode for PBX systems, when additional external D-channel
controllers are used, the DRDY signal to control the access has to be connected
to an external fast interrupt. Within the terminal mode, this arbitration can be done
with the Stop/Go bit on IOM-2.
S/T-Interface U-Interface
INTC-Q2 NH U
SPEF81912 NH
HV-SLIC
HV-SLIC
POTS-Interface
SLICOFI-2
IOM-2
V.24-Interface
V.24
Flash
SRAM
C165
Core
RAM
EBC
HDLC
C165H
PEC
XBUS
external BUS
C165H
Pin Descriptions
Data Sheet 18 2001-04-19
PRELIMINARY
- EXCERPT -
2 Pin Descriptions
2.1 C165H Pin Diagram
Figure 4 C165H Pin Configuration
P-TQFP-144
C165H
P0L(7:0) I/O or AD(7:0)
P0H(7:0) I/O or AD(15:8)
P1L(7:0)
I/O or A(7:0)
P1H(7:0) I/O or A(15:8)
P4(6:0) I/O or A(22:16)
RSTIN
NMI
RSTOUT
I/O or CLKOUT
WR/WRL
READY
EA
RD
ALE
EXnINT(7:0) P2(7:0)
I/O or HLDA
I/O or HOLD
I/O or CS(4:0)
I/O or BREQ
P6(4:0)
P6(6)
P6(5)
P6(7)
XTAL1
XTAL2
TDO
TCK
TMS
TDI JTAG
Port
DU
DD
IOM-2/PCM
Port DCL
FSC
I/O or BHE or WRH
P3(12)
P3(15)
P3(7:5,3)
GPT1/2
Port
Fast
I/O or MRST
I/O or MTSR
SSC/SCI
Port I/O or SCLK
Serial
P3(8)
P3(9)
P3(13)
or I/O
Interrupts
External
I/O or TxD
I/O or RxD
P3(10)
P3(11)
USART/ASC
Port
MicroController
Bus
P7(5:0)
GPIO
Port
TRST
TEST
CLKMODE
BRKOUT
BRKIN
OCDS
C165H
Pin Descriptions
Data Sheet 19 2001-04-19
PRELIMINARY
- EXCERPT -
2.2 C165H Pin Definitions and Functions
Table 2 Microprocessor Bus and Control Signals
Pin No. Symbol Input (I)
Output (O)
Function
60-63, 66-
69, 70-71,
77-78, 81-84
PORT0:
P0L0-
P0L7,
P0H0-
P0H7
I/O PORT0 consists of the two 8-bit bidirectional
I/O ports P0L and P0H. It is bitwise
programmable for input or output via direction
bits. For a pin configured as input, the output
driver is put into high-impedance.
In case of an external bus configuration,
PORT0 serves as the address (A) and
address/data (AD) bus in demultiplexed bus
modes.
Demultiplexed bus modes:
Data Path Width: 8-bit 16-bit
P0L0-P0L7: D0-D7 D0-D7
P0H0-P0H7: I/O D8-D15
Multiplexed bus modes:
Data Path Width: 8-bit 16-bit
P0L0-P0L7: AD0-AD7 AD0-AD7
P0H0-P0H7: A8-A15 AD8-AD15
87-90, 93-
96, 99-103,
109-111
PORT1:
P1L0-
P1L7,
P1H0-
P1H7
I/O PORT1 consists of the two 8-bit bidirectional
I/O ports P1L and P1H. It is bitwise
programmable for input or output via direction
bits. For a pin configured as input, the output
driver is put into high-impedance.
PORT1 is used as the 16-bit address bus (A)
in demultiplexed bus modes and also after
switching from a demultiplexed bus mode to a
multiplexed bus mode (see Chapter 7.3).
C165H
Pin Descriptions
Data Sheet 20 2001-04-19
PRELIMINARY
- EXCERPT -
31, 37-42 P4.0 -
P4.6
I/O
O
O
PORT4 is an 7-bit bidirectional I/O port. It is
bit-wise programmable for input or output via
direction bits. For a pin configured as input, the
output driver is put into high-impedance state.
In case of an external bus configuration, Port4
can be used to output the segment address
lines:
P40 A16 Least Significant Segment
Address Line
... ... ...
P4.6 A22 Most Significant Segment
Address Line
114 RSTIN I Reset Input with Schmitt-Trigger
characteristics. A low level at this pin for a
specified duration while the oscillator is
running resets the device. An internal pull-up
resistor permits power-on reset using only a
capacitor connected to VSS.
115 RSTOUT O Internal Reset Indication Output. This pin is set
to a low level when the C165H is executing
either a hardware-, software- or a watchdog
timer reset. RSTOUT remains low until the
C165H has initialized itself.
116 NMI I Non-Maskable Interrupt Input. A high to low
transition at this pin causes the CPU to vector
to the NMI trap routine. When the PWRDN
(power down) instruction is executed, the NMI
pin must be low in order to force the CPU to go
into power down mode. If NMI is high, when
PWRDN is executed, the device will continue
to run in normal mode. If not used, pin NMI
should be pulled high externally.
Table 2 Microprocessor Bus and Control Signals (cont’d)
Pin No. Symbol Input (I)
Output (O)
Function
C165H
Pin Descriptions
Data Sheet 21 2001-04-19
PRELIMINARY
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117-121,
124-126
P6.0-
P6.7
O
I/O
O
...
O
I
O
O
Port6 is an 8-bit bidirectional I/O port. It is bit-
wise programmable for input or output via
direction bits. For a pin configured as input, the
output driver is put into high-impedance state.
Port6 outputs can be configured as push/pull
or open-drain drivers.
P6.0 CS0 Chip Select 0 Output
... ... ...
P6.4 CS4 Chip Select 4 Output
P6.5 HOLD External Master Hold
Request Input
P6.6 HLDA Hold Acknowledge Output
P6.7 BREQ Bus Request Output
131-134,
137-140
P2.0-
P2.7
I/O
I
I
PORT2 is an 8-bit bidirectional I/O port. It is
bit-wise programmable for input or output via
direction bits. For a pin configured as input, the
output driver is put into high-impedance state.
Port2 outputs can be configured as push/pull
or open-drain drivers.
P2.0 EX0IN Fast External Interrupt 0
Input
P2.7 EX7IN Fast External Interrupt 7
Input
53 RD O External Memory Read Strobe. RD is
activated for every external instruction or data
read access.
54 WR/WRL O External Memory Write Strobe. In WR mode
this pin is activated for every external data
write access. In WRL mode this pin is
activated for low byte data write accesses on a
16-bit bus, and for every data write access on
an 8-bit bus. See WRCFG in register
SYSCON for mode selection.
56 ALE O Address Latch Enable Output. Can be used for
latching the address into external memory or
an address latch in the multiplexed bus
modes.
Table 2 Microprocessor Bus and Control Signals (cont’d)
Pin No. Symbol Input (I)
Output (O)
Function
C165H
Pin Descriptions
Data Sheet 22 2001-04-19
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55 READY I Ready Input. When the ready function is
enabled, a high level at this pin during an
external memory access will force the
insertion of memory cycle time waitstates until
the pin returns to an low level.
57 EA I External Access Enable pin. A low level at this
pin during and after Reset forces the CPU to
begin instruction execution out of external
memory.
Note: This pin must always be set to ’0’.
45-50 P7.0-
P7.5
I/O PORT7 is an 6-bit bidirectional I/O port. It is
bit-wise programmable for input or output via
direction bits. For a pin configured as input, the
output driver is put into high-impedance state.
Port7 outputs are push/pull drivers.
P7.0 GPIO0
...
P7.5 GPIO5
Table 2 Microprocessor Bus and Control Signals (cont’d)
Pin No. Symbol Input (I)
Output (O)
Function
C165H
Pin Descriptions
Data Sheet 23 2001-04-19
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Table 3 General Purpose I/O and Control Signals
Pin No. Symbol Input (I)
Output (O)
Function
18-21, 24-30 P3.3,
P3.5-
P3.13,
P3.15
I/O
I/O
I/O
O
I
I
I
I/O
I/O
O
I/O
O
O
I/O
O
PORT3 is a 11-bit bidirectional I/O port. It is
bit-wise programmable for input or output via
direction bits. For a pin configured as input, the
output driver is put into high-impedance state.
Port3 outputs can be configured as push/pull
or open-drain drivers.
The following PORT3 pins also serve for
alternate functions:
P3.3 T3OUT GPT1 Timer T3 Toggle Latch
Output
P3.5 T4IN GPT1 Timer T4 Input for
Count/Gate/Reload/Capture
Input for Timer 3 T3EUD
Input for Timer 2 T2EUD
P3.6 T3IN GPT1 Timer T3 Count/Gate/
Input
P3.7 T2IN GPT1 Timer T2 Input for
Count/Gate/Reload/Capture
P3.8 MRST SSC Master-Rec./Slave-
Transmit I/O
P3.9 MTSR SSC Master-Transmit/Slave-
Rec. O/I
P3.10 TxD0 ASC Clock/Data Output
(Async./Sync.)
P3.11 RxD0 ASC Data Input (Async.) or
I/O (Sync.)
P3.12 BHE External Memory High Byte
Enable Signal
WRH External Memory High Byte
Write Strobe
P3.13 SCLK SSC Master Clock Output/
Slave Clock Input (CPU
Clock)
P3.15 CLKOUT System Clock Output
(CPU Clock)
C165H
Pin Descriptions
Data Sheet 24 2001-04-19
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Table 4 IOM-2 Interface Signals
Pin No. Symbol Input (I)
Output (O)
Function
9 DU I/O, OD IOM-2 Data Upstream Signal pin. (From
subscriber to network). For the pin configured
as input, the output driver is put into high-
impedance state. Open-drain.
10 DD I/O, OD IOM-2 Data Downstream Signal pin. (From
network to subscriber). For the pin configured
as input, the output driver is put into high-
impedance state. Open-drain.
11 DCL I IOM-2 Data Clock Signal Input pin
12 FSC I IOM-2 Frame Sync. Clock Signal Input pin
Table 5 Clock Interface Signals
Pin No. Symbol Input (I)
Output (O)
Function
15 XTAL1 I External crystal input to the on-chip
oscillator. Clock input for direct driven clock
without using an external crystal. Function is
determined by the CLKMODE pin.
16 XTAL2 O Output from the oscillator amplifier circuit. To
clock the C165H from an external source,
drive XTAL1, while XTAL2 leaving
unconnected. Minimum and maximum high/
low and rise/fall times specified in the AC
characteristics must be observed.
13 CLKMODE I Clock Mode Select pin. CLKMODE must be
set to LOW if an external crystal is used. Set
to HIGH signal enables the direct clock input
path and switches the internal oscillator in
power down mode.
C165H
Pin Descriptions
Data Sheet 25 2001-04-19
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Table 6 Boundary Scan / JTAG / Test Interface Signals/OCDS
Pin No. Symbol Input (I)
Output (O)
Function
3 TCK I Boundary Scan Test Clock Input. There is no
internal pull device implemented. During
normal operation, it is recommended to
connect TCK to VSS.
4 TDI I Boundary Scan Test Data Input. An internal
pull-up device is connected to TDI. During
normal operation, TDI can be left open.
5 TDO O Boundary Scan Test Data Output. During
normal operation, the output TDO can be left
open.
6 TMS I Boundary Scan Test Mode Select Input,
internal pull-up.
144 TRST I Boundary Scan Test Reset. There is an
internal pull-up device implemented. TRST is
low active, which means the boundary scan
tap controller resets while TRST = ’0’.
For normal operation,
•TRST
can be connected to LOW signal
(using ’0’ signal or external pull-down
device) to keep the tap controller in reset
mode, or
•TRST
can be left open. In this case, the
reset is performed using the TMS/TCK
signals according to IEEE 1149.1
In boundary scan test mode, TRST can be left
open, since the internal pull-up device pro-
vides the necessary HIGH signal.
143 TEST I Test Mode Enable Pin.
HIGH signal enables the chip internal test
mode.
Note: In normal operation, TEST must be
connected to VSS (LOW signal) since
no internal Pull-Down resistor is
provided.
C165H
Pin Descriptions
Data Sheet 26 2001-04-19
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34 BRKIN I In OCDS mode, a falling edge from HIGH to
LOW signal on BRKIN forces the system to
stop. An internal pull-up resistor is provided.
35 BRKOUT O In OCDS mode, a falling edge on BRKOUT
indicates the trigger of a pre-selected OCDS
event.
Table 7 Power/Ground Signals
Pin No. Symbol Input (I)
Output (O)
Function
8, 23, 33, 44,
52, 59, 65,
76, 80, 86,
92, 98, 105,
113,
123,130,
136, 142
VDD - Digital Supply Voltage
Note: All pins must be connected to VDD.
7, 22, 32, 43,
51, 58, 64,
75, 79, 85,
91, 97, 104,
112, 122,
127, 135,141
VSS - Digital Ground
Note: All pins must be connected to VSS.
Table 6 Boundary Scan / JTAG / Test Interface Signals/OCDS
Pin No. Symbol Input (I)
Output (O)
Function
C165H
Pin Descriptions
Data Sheet 27 2001-04-19
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17 VDDAX - Analog Supply Voltage:
VDDAX supplies the oscillator circuitry only,
and is internal not connected to VDD in order
to separate possible noise influence from the
noise sensitive part. External, on board level,
the VDDAX can be connected to the same
power supply as the VDD.
14 VSSAX - Analog Ground
VSSAX is connected to the oscillator circuitry
Gound only, in order to separate possible
noise influence. External, on board level, the
VSSA can be connected to the same Ground
as the VSS.
Table 8 Unconnected Pins
Pin No. Symbol Input (I)
Output (O)
Function
1, 2, 36, 72,
73, 74, 106,
107, 108
unconnected - These pins are unconnected - no
function. Reserved for future use.
Table 7 Power/Ground Signals (cont’d)
Pin No. Symbol Input (I)
Output (O)
Function
C165H
Architectural Overview
Data Sheet 28 2001-04-19
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3 Architectural Overview
The architecture of the C165H combines the advantages of both RISC and CISC
processors in a very well-balanced way. The sum of the features which are combined
result in a high performance microcontroller, which is the right choice not only for today's
applications, but also for future engineering challenges. The C165H not only integrates
a powerful CPU core and a set of peripheral units into one chip, but also connects the
units in a very efficient way. One of the four buses used concurrently on the C165H is
the XBUS, an internal representation of the external bus interface. This bus provides a
standardized method of integrating application-specific peripherals to produce derivates
of the standard C165H.
Figure 5 C165H Functional Block Diagram
CPU
CORE
P1 P2 P3 P4 P6
P7P0
OSC
PLL WDT
JTAG
GPT1ASC GPT2
OCDS
IOM-2
BUS
SSC
CTL
Interrupt Controller PEC
XBUS Module
Internal
ROM RAM
C165H
C165H
Architectural Overview
Data Sheet 29 2001-04-19
PRELIMINARY
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3.1 Basic CPU Concepts and Optimizations
The main core of the CPU consists of a 4-stage instruction pipeline, a 16-bit arithmetic
and logic unit (ALU) and dedicated SFRs. Additional hardware is provided for a separate
multiply and divide unit, a bit-mask generator and a barrel shifter.
Figure 6 CPU Block Diagram
To meet the demand for greater performance and flexibility, a number of areas has been
optimized in the processor core. Functional blocks in the CPU core are controlled by
signals from the instruction decode logic. These are summarized below, and described
in detail in the following sections:
1. High Instruction Bandwidth / Fast Execution
2. High Function 8-bit and 16-bit Arithmetic and Logic Unit
3. Extended bit Processing and Peripheral Control
4. High Performance Branch-, Call-, and Loop Processing
5. Consistent and Optimized Instruction Formats
6. Programmable Multiple Priority Interrupt Structure
MCB02147
CPU
SP
STKOV
STKUN
Instr. Reg.
Instr. Ptr.
Exec. Unit
4-Stage
Pipeline
MDH
MDL
PSW
SYSCON Context Ptr.
Mul/Div-HW
R15
R0
General
Purpose
Registers
Bit-Mask Gen
Barrel - Shifter
ALU
(16-bit)
Data Page Ptr. Code Seg. Ptr.
Internal
RAM
R15
R0
ROM
16
16
32
BUSCON 0
BUSCON 1
BUSCON 2
BUSCON 3
BUSCON 4 ADDRSEL 4
ADDRSEL 3
ADDRSEL 2
ADDRSEL 1
C165H
Architectural Overview
Data Sheet 30 2001-04-19
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High Instruction Bandwidth / Fast Execution
Based on the hardware provisions, most of the C165H's instructions can be executed in
just one machine cycle, which requires 55.6 ns at 36 MHz CPU clock. For example, shift
and rotate instructions are always processed within one machine cycle, independent of
the number of bits to be shifted.
Branch-, multiply- and divide instructions normally take more than one machine cycle.
These instructions, however, have also been optimized. For example, branch
instructions only require an additional machine cycle, when a branch is taken, and most
branches taken in loops require no additional machine cycles at all, due to the so-called
‘Jump Cache’.
A 32-bit / 16-bit division takes 1µs, a 16-bit * 16-bit multiplication takes 0.5 µs.
The instruction cycle time has been dramatically reduced through the use of instruction
pipelining. This technique allows the core CPU to process portions of multiple sequential
instruction stages in parallel. The following four stage pipeline provides the optimum
balancing for the CPU core:
FETCH: In this stage, an instruction is fetched from the RAM or from the external
memory, based on the current IP value.
DECODE: In this stage, the previously fetched instruction is decoded and the required
operands are fetched.
EXECUTE: In this stage, the specified operation is performed on the previously fetched
operands.
WRITE BACK: In this stage, the result is written to the specified location.
If this technique were not used, each instruction would require four machine cycles. This
increased performance allows a greater number of tasks and interrupts to be processed.
Instruction Decoder
Instruction decoding is primarily generated from PLA outputs based on the selected
opcode. No microcode is used and each pipeline stage receives control signals staged
in control registers from the decode stage PLAs. Pipeline holds are primarily caused by
wait states for external memory accesses and cause the holding of signals in the control
registers. Multiple-cycle instructions are performed through instruction injection and
simple internal state machines which modify required control signals.
High Function 8-bit and 16-bit Arithmetic and Logic Unit
All standard arithmetic and logical operations are performed in a 16-bit ALU. In addition,
for byte operations, signals are provided from bits six and seven of the ALU result to
correctly set the condition flags. Multiple precision arithmetic is provided through a
'CARRY-IN' signal to the ALU from previously calculated portions of the desired
operation. Most internal execution blocks have been optimized to perform operations on
either 8-bit or 16-bit quantities. Once the pipeline has been filled, one instruction is
C165H
Architectural Overview
Data Sheet 31 2001-04-19
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completed per machine cycle, except for multiply and divide. An advanced Booth
algorithm has been incorporated to allow four bits to be multiplied and two bits to be
divided per machine cycle. Thus, these operations use two coupled 16-bit registers, MDL
and MDH, and require four and nine machine cycles, respectively, to perform a 16-bit by
16-bit (or 32-bit by 16-bit) calculation plus one machine cycle to setup and adjust the
operands and the result. Even these longer multiply and divide instructions can be
interrupted during their execution to allow for very fast interrupt response. Instructions
have also been provided to allow byte packing in memory while providing sign extension
of bytes for word wide arithmetic operations. The internal bus structure also allows
transfers of bytes or words to or from peripherals based on the peripheral requirements.
A set of consistent flags is automatically updated in the PSW after each arithmetic,
logical, shift, or movement operation. These flags allow branching on specific conditions.
Support for both signed and unsigned arithmetic is provided through user-specifiable
branch tests. These flags are also preserved automatically by the CPU upon entry into
an interrupt or trap routine.
All targets for branch calculations are also computed in the central ALU.
A 16-bit barrel shifter provides multiple bit shifts in a single cycle. Rotates and arithmetic
shifts are also supported.
Extended Bit Processing and Peripheral Control
A large number of instructions has been dedicated to bit processing. These instructions
provide efficient control and testing of peripherals while enhancing data manipulation.
Unlike other microcontrollers, these instructions provide direct access to two operands
in the bit-addressable space without requiring to move them into temporary flags.
The same logical instructions available for words and bytes are also supported for bits.
This allows the user to compare and modify a control bit for a peripheral in one
instruction. Multiple bit shift instructions have been included to avoid long instruction
streams of single bit shift operations. These are also performed in a single machine
cycle.
In addition, bit field instructions have been provided, which allow the modification of
multiple bits from one operand in a single instruction.
High Performance Branch-, Call-, and Loop Processing
Due to the high percentage of branching in controller applications, branch instructions
have been optimized to require one extra machine cycle only when a branch is taken.
This is implemented by precalculating the target address while decoding the instruction.
To decrease loop execution overhead, three enhancements have been provided:
• The first solution provides single cycle branch execution after the first iteration of a
loop. Thus, only one machine cycle is lost during the execution of the entire loop. In
loops which fall through upon completion, no machine cycles are lost when exiting the
C165H
Architectural Overview
Data Sheet 32 2001-04-19
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loop. No special instructions are required to perform loops, and loops are
automatically detected during execution of branch instructions.
• The second loop enhancement allows the detection of the end of a table and avoids
the use of two compare instructions embedded in loops. One simply places the lowest
negative number at the end of the specific table, and specifies branching if neither this
value nor the compared value have been found. Otherwise the loop is terminated if
either condition has been met. The terminating condition can then be tested.
• The third loop enhancement provides a more flexible solution than the Decrement and
Skip on Zero instruction which is found in other microcontrollers. Through the use of
Compare and Increment or Decrement instructions, the user can make comparisons
to any value. This allows loop counters to cover any range. This is particularly
advantageous in table searching.
Saving of system state is automatically performed on the internal system stack avoiding
the use of instructions to preserve state upon entry and exit of interrupt or trap routines.
Call instructions push the value of the IP on the system stack, and require the same
execution time as branch instructions.
Instructions have also been provided to support indirect branch and call instructions.
This supports implementation of multiple CASE statement branching in assembler
macros and high level languages.
Consistent and Optimized Instruction Formats
To obtain optimum performance in a pipelined design, an instruction set has been
designed which incorporates concepts from Reduced Instruction Set Computing (RISC).
These concepts primarily allow fast decoding of the instructions and operands while
reducing pipeline holds. These concepts, however, do not preclude the use of complex
instructions, which are required by microcontroller users. The following goals were used
to design the instruction set:
1. Provide powerful instructions to perform operations which currently require
sequences of instructions and are frequently used. Avoid transfer into and out of
temporary registers such as accumulators and carry bits. Perform tasks in parallel
such as saving state upon entry into interrupt routines or subroutines.
2. Avoid complex encoding schemes by placing operands in consistent fields for each
instruction. Also avoid complex addressing modes which are not frequently used. This
decreases the instruction decode time while also simplifying the development of
compilers and assemblers.
3. Provide most frequently used instructions with one-word instruction formats. All other
instructions are placed into two-word formats. This allows all instructions to be placed
on word boundaries, which alleviates the need for complex alignment hardware. It
also has the benefit of increasing the range for relative branching instructions.
C165H
Architectural Overview
Data Sheet 33 2001-04-19
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The high performance offered by the hardware implementation of the CPU can efficiently
be utilized by a programmer via the highly functional C165H instruction set which
includes the following instruction classes:
• Arithmetic Instructions
• Logical Instructions
• Boolean Bit Manipulation Instructions
• Compare and Loop Control Instructions
• Shift and Rotate Instructions
• Prioritize Instruction
• Data Movement Instructions
• System Stack Instructions
• Jump and Call Instructions
• Return Instructions
• System Control Instructions
• Miscellaneous Instructions
Possible operand types are bits, bytes and words. Specific instruction support the
conversion (extension) of bytes to words. A variety of direct, indirect or immediate
addressing modes are provided to specify the required operands.
Programmable Multiple Priority Interrupt System
The following enhancements have been included to allow processing of a large number
of interrupt sources:
1. Peripheral Event Controller (PEC): This processor is used to off-load many interrupt
requests from the CPU. It avoids the overhead of entering and exiting interrupt or trap
routines by performing single-cycle interrupt-driven byte or word data transfers with
an optional increment of either the PEC source or the destination pointer. Just one
cycle is 'stolen' from the current CPU activity to perform a PEC service.
2. Multiple Priority Interrupt Controller: This controller allows all interrupts to be placed at
any specified priority. Interrupts may also be grouped, which provides the user with
the ability to prevent similar priority tasks from interrupting each other. For each of the
possible interrupt sources there is a separate control register, which contains an
interrupt request flag, an interrupt enable flag and an interrupt priority bitfield. Once
having been accepted by the CPU, an interrupt service can only be interrupted by a
higher prioritized service request. For standard interrupt processing, each of the
possible interrupt sources has a dedicated vector location.
3. Multiple Register Banks: This feature allows the user to specify up to sixteen general
purpose registers located anywhere in the internal RAM. A single one-machine-cycle
instruction allows to switch register banks from one task to another.
4. Interruptable Multiple Cycle Instructions: Reduced interrupt latency is provided by
allowing multiple-cycle instructions (multiply, divide) to be interruptable.
C165H
Architectural Overview
Data Sheet 34 2001-04-19
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With an interrupt response time within a range from just 140 ns to 280 ns (in case of
internal program execution), the C165H is capable of reacting very fast on non-
deterministic events.
Its fast external interrupt inputs are sampled every 28 ns and allow to recognize even
very short external signals.
The C165H also provides an excellent mechanism to identify and to process exceptions
or error conditions that arise during run-time, so called 'Hardware Traps'. Hardware traps
cause an immediate non-maskable system reaction which is similiar to a standard
interrupt service (branching to a dedicated vector table location). The occurrence of a
hardware trap is additionally signified by an individual bit in the trap flag register (TFR).
Except for another higher prioritized trap service being in progress, a hardware trap will
interrupt any current program execution. In turn, hardware trap services can normally not
be interrupted by standard or PEC interrupts.
Software interrupts are supported by means of the 'TRAP' instruction in combination with
an individual trap (interrupt) number.
3.2 On-Chip System Resources
C165H controllers provide a number of powerful system resources designed around the
CPU. The combination of CPU and these resources results in the high performance of
the members of this controller family.
Peripheral Event Controller (PEC) and Interrupt Control
The Peripheral Event Controller allows to respond to an interrupt request with a single
data transfer (word or byte) which only consumes one instruction cycle and does not
require to save and restore the machine status. Each interrupt source is prioritized every
machine cycle in the interrupt control block. If PEC service is selected, a PEC transfer is
started. If CPU interrupt service is requested, the current CPU priority level stored in the
PSW register is tested to determine whether a higher priority interrupt is currently being
serviced. When an interrupt is acknowledged, the current state of the machine is saved
on the internal system stack and the CPU branches to the system specific vector for the
peripheral.
The PEC contains a set of SFRs which store the count value and control bits for eight
data transfer channels. In addition, the PEC uses a dedicated area of RAM which
contains the source and destination addresses. The PEC is controlled similar to any
other peripheral through SFRs containing the desired configuration of each channel.
An individual PEC transfer counter is implicitly decremented for each PEC service
except forming in the continuous transfer mode. When this counter reaches zero, a
standard interrupt is performed to the vector location related to the corresponding
source. PEC services are very well suited, for example, to move register contents to/from
C165H
Architectural Overview
Data Sheet 35 2001-04-19
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a memory table. C165H has 8 PEC channels each of which offers such fast interrupt-
driven data transfer capabilities.
Memory Areas
The memory space of the C165H is configured in a Von Neumann architecture which
means that code memory, data memory, registers and I/O ports are organized within the
same linear address space which covers up to 8 MBytes. The entire memory space can
be accessed bytewise or wordwise. Particular portions of the on-chip memory have
additionally been made directly bit addressable.
A 16-bit wide internal RAM (IRAM) provides fast access to General Purpose Registers
(GPRs), user data (variables) and system stack. The internal RAM may also be used for
code. A unique decoding scheme provides flexible user register banks in the internal
memory while optimizing the remaining RAM for user data. The size of the internal RAM
is 3 KByte.
The CPU disposes of an actual register context consisting of up to 16 wordwide and/or
bytewide GPRs, which are physically located within the on-chip RAM area. A Context
Pointer (CP) register determines the base address of the active register bank to be
accessed by the CPU at a time. The number of register banks is only restricted by the
available internal RAM space. For easy parameter passing, a register bank may overlap
others.
A system stack of up to 1024 words is provided as a storage for temporary data. The
system stack is also located within the on-chip RAM area, and it is accessed by the CPU
via the stack pointer (SP) register. Two separate SFRs, STKOV and STKUN, are
implicitly compared against the stack pointer value upon each stack access for the
detection of a stack overflow or underflow.
Hardware detection of the selected memory space is placed at the internal memory
decoders and allows the user to specify any address directly or indirectly and obtain the
desired data without using temporary registers or special instructions.
For Special Function Registers 1024 Bytes of the address space are reserved. The
standard Special Function Register area (SFR) uses 512 bytes, while the Extended
Special Function Register area (ESFR) uses the other 512 bytes. (E)SFRs are wordwide
registers which are used for controlling and monitoring functions of the different on-chip
units. Unused (E)SFR addresses are reserved for future members of the C165H family
with enhanced functionality.
External Bus Interface
In order to meet the needs of designs where more memory is required than is provided
on chip, up to 8 MBytes of external RAM and/or ROM can be connected to the
microcontroller via its external bus interface. The integrated External Bus Controller
(EBC) allows to access external memory and/or peripheral resources in a very flexible
C165H
Architectural Overview
Data Sheet 36 2001-04-19
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way. For up to five address areas the bus mode (multiplexed / demultiplexed), the data
bus width (8-bit / 16-bit) and even the length of a bus cycle (waitstates, signal delays)
can be selected independently. This allows to access a variety of memory and peripheral
components directly and with maximum efficiency. If the device does not run in Single
Chip Mode, where no external memory is required, the EBC can control external
accesses in one of the following four different external access modes:
16-/18-/20-/24-bit Addresses, 16-bit Data, Demultiplexed
16-/18-/20-/24-bit Addresses, 8-bit Data, Demultiplexed
16-/18-/20-/24-bit Addresses, 16-bit Data, Multiplexed
16-/18-/20-/24-bit Addresses, 8-bit Data, Multiplexed
The demultiplexed bus modes use PORT1 for addresses and PORT0 for data input/
output. The multiplexed bus modes use PORT0 for both addresses and data input/
output. All modes use Port 4 for the upper address lines (A16...) if selected.
Important timing characteristics of the external bus interface (waitstates, ALE length and
Read/Write Delay) have been made programmable to allow the user the adaption of a
wide range of different types of memories and/or peripherals. Access to very slow
memories or peripherals is supported via a particular 'Ready' function.
For applications which require less than 64 KBytes of address space, a non-segmented
memory model can be selected, where all locations can be addressed by 16 bits, and
thus Port 4 is not needed as an output for the upper address bits (A22/A19/A17...A16),
as is the case when using the segmented memory model.
On-chip XBUS is an internal representation of the external bus and allows to access
integrated application-specific peripherals/modules in the same way as external
components. It provides a defined interface for these customized peripherals.
3.3 Clock Generation Concept
The on-chip clock generator provides the C165H with its basic clock signal that controls
all activities of the controller hardware. Its oscillator can either run with an external crystal
and appropriate oscillator circuitry (see also recommendations in chapter „Dedicated
Pins“) or it can be driven by an external oscillator. The oscillator either directly feeds the
external clock signal to the controller hardware (through buffers), divides the external
clock frequency by 2 or 4, or feeds an on-chip phase locked loop (PLL) which multiplies
the input frequency by a selectable factor F. This resulting internal clock signal is also
referred to as “CPU clock”. Two separated clock signals are generated for the CPU itself
and the peripheral part of the chip. While the CPU clock is stopped during the idle mode,
the peripheral clock keeps running. Both clocks are switched off, when the power down
mode is entered.
C165H
Architectural Overview
Data Sheet 37 2001-04-19
PRELIMINARY
- EXCERPT -
Note: Pin13 CLKMODE must be connected to LOW signal if an external crystal is used.
Pin cockmode connected to HIGH signal enables the direct input path and
switches the oscillator circuit in power down mode.
The on-chip PLL circuit allows operation of the C165H on a low frequency external clock
while still providing maximum performance. The PLL generates a CPU clock signal with
50% duty cycle. The PLL also provides fail safe mechanisms which allow the detection
of frequency deviations and the execution of emergency actions in case of an external
clock failure.
Figure 7 shows the general clock generation concept of the C165H.
The following constrains must be taken into account when considering the clock concept:
1. The maximum CPU clock frequency is 36 MHz (18 MIPS).
2. All AC and DC specifications described in Chapter 23, "AC/DC Characteristics" must
be fulfilled.
3. The input frequency of the internal oscillator circuit is 4 MHz up to 20 MHz. This
applies only, if an external crystal is used.
4. In direct drive mode, the internal oscillator circuit is bypassed. The clock input
frequency range is 4 MHz up to 36 MHz.
5. The IOM-2 module requires a minimum CPU clock of 5 times bitrate clock (BCL) on
pin DCL. In PCM or LT mode the resulting clock is 5 * 2 MHz = 10 MHz. In TE mode
the minimum CPU clock frequency is 5 * 0.7 MHz ≈ 4 MHz.
C165H
Architectural Overview
Data Sheet 38 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 7 C165H General Clock Concept
Note: All supported clock modes for the C165H are shown in Table 9. Because of the
limited size of the register, there are not all combinations adjustable, which can be
derived theoretical from Figure 7.
% 2
% 2
Phase
Detector
Charge
Pump
Loop
Filter
VCO
common mode feedback
CPU Divider
1/(6,8,12,24)
Lock
Detection
Feedback
Divider 1/6
(288 MHz
@ 8 MHz)
PLL UNIT
CLOCK UNIT
Mux
Mux
Mux
Mux
Clock
Control
Unit
CLKCFG
Pin 15
XTAL1
Pin 16
XTAL2
Pin 13
clkmode
Pin 30
clockout
Main CPU_Clock
OSC
(SYSCON: P0H7:5)
f
CPU
= f
IN
x F
f
OSC
OWD
control signals
Div1
Div2
fXTAL
Mux
Slow
Down
Divider
SYSCON2.7
Reload
SYSCON2.10:14
C165H
Architectural Overview
Data Sheet 39 2001-04-19
PRELIMINARY
- EXCERPT -
Table 9 C165H Clock Generation Modes
PLL Operation
On power-up the PLL provides a stable clock signal within ca. 1 ms after VDD has
reached 3.3 V±10%, even if there is no external clock signal (in this case the PLL will run
on its basic frequency of 2...5 MHz). The PLL starts synchronizing with the external clock
signal as soon as it is available. Within ca. 1 ms after stable oscillations of the external
clock within the specified frequency range the PLL will be synchronous with this clock at
a frequency of F*f
OSC, ie. the PLL locks to the external clock.
Note: If the C165H is required to operate on the desired CPU clock directly after reset
make sure that RSTIN remains active until the PLL has locked (ca. 1 ms).
When PLL operation is selected the CPU clock is a selectable multiple of the oscillator
frequency, ie. the input frequency. The table above lists the possible selections.
The PLL constantly synchronizes to the external clock signal. Due to the fact that the
external frequency is 1/F’th of the PLL output frequency the output frequency may be
slightly higher or lower than the desired frequency. This jitter is irrelevant for longer time
periods. For short periods (1...4 CPU clock cycles) it remains below 4%.
When the PLL detects a missing input clock signal it generates an interrupt request. This
warning interrupt indicates that the PLL frequency is no more locked, ie. no more stable.
This occurs when the input clock is unstable and especially when the input clock fails
completely, eg. due to a broken crystal. In this case the synchronization mechanism will
reduce the PLL output frequency down to the PLL’s basic frequency (2...5 MHz). The
basic frequency is still generated and allows the CPU to execute emergency actions in
case of a loss of the external clock.
P0H.7-P0H.5 Frequency Divider Activation
001 fXTAL * 0.5 direct drive, D1 not active, D2 active, PLL free running (2..5 MHZ)
Note: The PLL can be switched off completely by setting bit
PLLDIS = ’1’ (SYSCON3.13, see page 429).
010 fXTAL * 1.5 D1 not active, D2 not active, F = 1.5
011 fXTAL * 1.0 direct drive, D1 not active, D2 not active, PLL free running (2..5
MHz)
Note: The PLL can be switched off completely by setting bit
PLLDIS = ’1’ (SYSCON3.13, see page 429).
100 fXTAL * 6.0 D1 not active, D2 not active, F = 6.0
101 fXTAL * 1.125 D1 active, D2 active, F = 1.125
110 fXTAL * 3.0 D1 not active, D2 not active, F = 3.0
111 fXTAL * 4.5 D1 not active, D2 not active, F = 4.5, Default Mode
000 fXTAL * 0.375 D1 active, D2 active, F = 0.375
C165H
Architectural Overview
Data Sheet 40 2001-04-19
PRELIMINARY
- EXCERPT -
Prescaler Operation
When pins P0.15-13 (P0H.7-5) are equal ’001’ during reset the CPU clock is derived
from the internal oscillator (input clock signal) by a 2:1 prescaler (see Table 9).
The frequency of fCPU is half the frequency of fXTAL and the high and low time of fCPU (ie.
the duration of an individual TCL) is defined by the period of the input clock fXTAL.
The timings listed in the ’AC Characteristics’ of the data sheet that refer to TCLs
therefore can be calculated using the period of fXTAL for any TCL.
Direct Drive
When pins P0.15-13 (P0H.7-5) equal ’011’ during reset the clock system is directly
driven from the internal oscillator with the input clock signal, ie. fOSC = fCPU.
The maximum input clock frequency depends on the clock signal’s duty cycle, because
the minimum values for the clock phases (TCLs) must be respected.
Oscillator Watchdog
The C165H provides an Oscillator Watchdog (OWD) which monitors the clock signal
generated by the on-chip oscillator (either with a crystal or via external clock drive) in
prescaler or direct drive mode. For this operation the PLL provides a clock signal which
is used to supervise transitions on the oscillator clock. This PLL clock is independent
from the XTAL1 clock. When the expected oscillator clock transitions are missing the
OWD activates the PLL Unlock / OWD interrupt node and supplies the CPU with the PLL
clock signal. Under these circumstances the PLL will oscillate with its basic frequency.
The OWD’s interrupt output can be disabled by setting bit OSCENBL = '0' (default after
reset) in SYSCON register. In this case no oscillator watchdog interrupt request is
generated and the CPU clock signal is derived from the oscillator clock in any case
Note: The CPU clock source is only switched back to the oscillator clock after a
hardware reset.
3.4 On-Chip Peripheral Blocks
The C165H clearly separates peripherals from the core. This structure permits the
maximum number of operations to be performed in parallel and allows peripherals to be
added or deleted from family members without modifications to the core. Each functional
block processes data independently and communicates information over common
buses. Peripherals are controlled by data written to the respective Special Function
Registers (SFRs). These SFRs are located either within the standard SFR area
(00’FE00H...00’FFFFH) or within the extended ESFR area (00’F000H...00’F1FFH).
These built in peripherals either allow the CPU to interface with the external world, or
provide functions on-chip that otherwise were to be added externally in the respective
system.
C165H
Architectural Overview
Data Sheet 41 2001-04-19
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C165H peripherals are:
• Two General Purpose Timer Blocks (GPT1 and GPT2)
• An Asynchronous/Synchronous Serial Interface (ASC)
• A High-Speed Synchronous Serial Interface (SSC)
• An IOM-2 Interface (IOM-2)
• A Watchdog Timer (WDT)
• Seven I/O ports with a total of 72 I/O lines
Each peripheral also contains a set of Special Function Registers (SFRs), which control
the functionality of the peripheral and temporarily store intermediate data results. Each
peripheral has an associated set of status flags. Individually selected clock signals are
generated for each peripheral from binary multiples of the CPU clock.
Peripheral Interfaces
The on-chip peripherals generally have two different types of interfaces, an interface to
the CPU and an interface to external hardware. Communication between CPU and
peripherals is performed through Special Function Registers (SFRs) and interrupts. The
SFRs serve as control/status and data registers for the peripherals. Interrupt requests
are generated by the peripherals based on specific events which occur during their
operation (eg. operation complete, error, etc.).
For interfacing with external hardware, specific pins of the parallel ports are used, when
an input or output function has been selected for a peripheral. During this time, the port
pins are controlled by the peripheral (when used as outputs) or by the external hardware
which controls the peripheral (when used as inputs). This is called the 'alternate (input
or output) function' of a port pin, in contrast to its function as a general purpose I/O pin.
Peripheral Timing
Internal operation of CPU and peripherals is based on the CPU clock (fCPU). The on-chip
oscillator derives the CPU clock from the crystal or from the external clock signal. The
clock signal which is gated to the peripherals is independent from the clock signal which
feeds the CPU. During Idle mode the CPU’s clock is stopped while the peripherals
continue their operation. Peripheral SFRs may be accessed by the CPU once per state.
When an SFR is written to by software in the same state where it is also to be modified
by the peripheral, the software write operation has priority. Further details on peripheral
timing are included in the specific sections about each peripheral.
Programming Hints
Access to SFRs
All SFRs reside in data page 3 of the memory space. The following addressing
mechanisms allow to access the SFRs:
C165H
Architectural Overview
Data Sheet 42 2001-04-19
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• indirect or direct addressing with 16-bit (mem) addresses it must be guaranteed that
the used data page pointer (DPP0...DPP3) selects data page 3.
• accesses via the Peripheral Event Controller (PEC) use the SRCPx and DSTPx
pointers instead of the data page pointers
•short 8-bit (reg) addresses to the standard SFR area do not use the data page
pointers but directly access the registers within this 512 Byte area.
•short 8-bit (reg) addresses to the extended ESFR area require switching to the 512
Byte extended SFR area. This is done via the EXTension instructions EXTR,
EXTP(R), EXTS(R).
Byte write operations to word wide SFRs via indirect or direct 16-bit (mem) addressing
or byte transfers via the PEC force zeros in the non-addressed byte. Byte write
operations via short 8-bit (reg) addressing can only access the low byte of an SFR and
force zeros in the high byte. It is therefore recommended, to use the bit field instructions
(BFLDL and BFLDH) to write to any number of bits in either byte of an SFR without
disturbing the non-addressed byte and the unselected bits.
Reserved Bits
Some of the bits which are contained in the C165H's SFRs are marked as 'Reserved'.
User software should never write '1's to reserved bits. These bits are currently not
implemented and may be used in future products to invoke new functions. In this case,
the active state for these functions will be '1', and the inactive state will be '0'. Therefore
writing only ‘0’s to reserved locations provides portability of the current software to future
devices. Read accesses to reserved bits return ‘0’s.
Parallel Ports
The C165H provides up to 72 I/O lines which are organized into seven input/output ports.
All port lines are bit-addressable, and all input/output lines are individually (bit-wise)
programmable as inputs or outputs via direction registers. The I/O ports are true
bidirectional ports which are switched to high impedance state when configured as
inputs. The output drivers of three I/O ports can be configured (pin by pin) for push/pull
operation or open-drain operation via control registers. During the internal reset, all port
pins are configured as inputs.
All port lines have programmable alternate input or output functions associated with
them. PORT0 and PORT1 may be used as address and data lines when accessing
external memory, while Port 4 outputs the additional segment address bits A22/A19/
A17...A16 in systems where segmentation is used to access more than 64 KBytes of
memory. Port 6 provides optional bus arbitration signals (BREQ, HLDA, HOLD) and chip
select signals. Port 2 accepts the fast external interrupt inputs. Port 3 includes alternate
functions of timers, serial interfaces, the optional bus control signal BHE and the system
clock output (CLKOUT). Port 7 is used for general purpose I/Os. All port lines that are
not used for these alternate functions may be used as general purpose I/O lines.
C165H
Architectural Overview
Data Sheet 43 2001-04-19
PRELIMINARY
- EXCERPT -
Serial Channels
Serial communication with other microcontrollers, processors, terminals or external
peripheral components is provided by two serial interfaces with different functionality, an
Asynchronous/Synchronous Serial Channel (ASC) and a High-Speed Synchronous
Serial Channel (SSC).
ASC is upward compatible with the serial ports of the Infineon 8-bit microcontroller
families and supports full-duplex asynchronous communication at up to 2.25 MBaud and
half-duplex synchronous communication at up to 4.5 MBaud @ 36 MHz CPU clock.
A dedicated baud rate generator allows to set up all standard baud rates without
oscillator tuning. For transmission, reception and error handling 4 separate interrupt
vectors are provided. In asynchronous mode, 8- or 9-bit data frames are transmitted or
received, preceded by a start bit and terminated by one or two stop bits. For
multiprocessor communication, a mechanism to distinguish address from data bytes has
been included (8-bit data plus wake up bit mode).
In synchronous mode, the ASC transmits or receives bytes (8 bits) synchronously to a
shift clock which is generated by the ASC. The ASC always shifts the LSB first. A loop
back option is available for testing purposes.
A number of optional hardware error detection capabilities has been included to increase
the reliability of data transfers. A parity bit can automatically be generated on
transmission or be checked on reception. Framing error detection allows to recognize
data frames with missing stop bits. An overrun error will be generated, if the last
character received has not been read out of the receive buffer register at the time the
reception of a new character is complete.
SSC supports full-duplex synchronous communication at up to 18 Mbaud @ 36 MHz
CPU clock in SSC master mode and up to 9 MBaud @ 36 MHz in SSC slave mode. It
may be configured so it interfaces with serially linked peripheral components. A
dedicated baud rate generator allows to set up all standard baud rates without oscillator
tuning. For transmission, reception and error handling 3 separate interrupt vectors are
provided.
The SSC transmits or receives characters of 2...16 bits length synchronously to a shift
clock which can be generated by the SSC (master mode) or by an external master (slave
mode). The SSC can start shifting with the LSB or with the MSB and allows the selection
of shifting and latching clock edges as well as the clock polarity. A number of optional
hardware error detection capabilities has been included to increase the reliability of data
transfers. Transmit and receive error supervise the correct handling of the data buffer.
Phase and baudrate error detect incorrect serial data.
General Purpose Timer (GPT) Unit
The GPT units represent a very flexible multifunctional timer/counter structure which
may be used for many different time related tasks such as event timing and counting,
pulse width and duty cycle measurements, pulse generation, or pulse multiplication.
C165H
Architectural Overview
Data Sheet 44 2001-04-19
PRELIMINARY
- EXCERPT -
The five 16-bit timers are organized in two separate modules, GPT1 and GPT2. Each
timer in each module may operate independently in a number of different modes, or may
be concatenated with another timer of the same module.
Each timer can be configured individually for one of three basic modes of operation,
which are Timer, Gated Timer, and Counter Mode. In Timer Mode the input clock for a
timer is derived from the internal CPU clock divided by a programmable prescaler, while
Counter Mode allows a timer to be clocked in reference to external events (via TxIN).
Pulse width or duty cycle measurement is supported in Gated Timer Mode where the
operation of a timer is controlled by the ‘gate’ level on its external input pin TxIN.
The count direction (up/down) for each timer is programmable by software or may
additionally be altered dynamically by an external signal (TxEUD) to facilitate eg. position
tracking.
The core timers T3 and T6 have output toggle latches (TxOTL) which change their state
on each timer over-flow/underflow. The state of these latches may be output on port pins
(TxOUT) or may be used internally to concatenate the core timers with the respective
auxiliary timers resulting in 32/33-bit timers/counters for measuring long time periods
with high resolution.
Various reload or capture functions can be selected to reload timers or capture a timer’s
contents triggered by an external signal or a selectable transition of toggle latch TxOTL.
Watchdog Timer
The Watchdog Timer represents one of the fail-safe mechanisms which have been
implemented to prevent the controller from malfunctioning for longer periods of time.
The Watchdog Timer is always enabled after a reset of the chip, and can only be
disabled in the time interval until the EINIT (end of initialization) instruction has been
executed. Thus, the chip’s start-up procedure is always monitored. The software has to
be designed to service the Watchdog Timer before it overflows. If, due to hardware or
software related failures, the software fails to do so, the Watchdog Timer overflows and
generates an internal hardware reset and pulls the RSTOUT pin low in order to allow
external hardware components to reset.
The Watchdog Timer is a 16-bit timer, clocked with the CPU clock divided either by 2 or
by 128. The high byte of the Watchdog Timer register can be set to a prespecified reload
value (stored in WDTREL) in order to allow further variation of the monitored time
interval. Each time it is serviced by the application software, the high byte of the
Watchdog Timer is reloaded.
3.5 Protected Bits
The C165H provides a special mechanism to protect bits which can be modified by the
on-chip hardware from being changed unintentionally by software accesses to related
bits (see also chapter “The Central Processing Unit”).
C165H
Architectural Overview
Data Sheet 45 2001-04-19
PRELIMINARY
- EXCERPT -
The following bits are protected:
Σ = 33 protected bits in the C165H
Register Bit Name Notes
T2IC, T3IC, T4IC T2IR, T3IR, T4IR GPT1 timer interrupt request flags
T5IC, T6IC T5IR, T6IR GPT2 timer interrupt request flags
CRIC CRIR GPT2 CAPREL interrupt request flag
T3CON, T6CON T3OTL, T6OTL GPTx timer output toggle latches
S0TIC, S0TBIC S0TIR, S0TBIR ASC transmit(buffer) interrupt request flags
S0RIC, S0EIC S0RIR, S0EIR ASC receive/error interrupt request flags
S0CON S0REN ASC receiver enable flag
SSCTIC, SSCRIC SSCTIR, SSCRIR SSC transmit/receive interrupt request flags
SSCEIC SSCEIR SSC error interrupt request flag
SSCCON SSCBSY SSC busy flag
SSCCON SSCBE, SSCPE SSC error flags
SSCCON SSCRE, SSCTE SSC error flags
TFR TFR.15,14,13 Class A trap flags
TFR TFR.7,3,2,1,0 Class B trap flags
XPyIC (y=3...0) XPyIR (y=3...0) X-Peripheral y interrupt request flag
C165H
Memory Organization
Data Sheet 46 2001-04-19
PRELIMINARY
- EXCERPT -
4 Memory Organization
The memory space of the C165H is configured in a “Von Neumann” architecture. This
means that code and data are accessed within the same linear address space. All of the
physically separated memory areas, internal RAM, the internal Special Function
Register Areas (SFRs and ESFRs), the address areas for integrated XBUS peripherals
and external memory are mapped into one common address space.
The C165H provides a total addressable memory space of 8 MBytes. This address
space is arranged as 128 segments of 64 KBytes each, and each segment is again
subdivided into four data pages of 16 KBytes each (see Figure 8).
Figure 8 Memory Areas and Address Space
Internal
IRAM/SFR
00’0000H
00’FFFFH
XRAM
SFR Area 00’FFFFH
00’F000H
00’E000H
00’8000H
00’E000H
ESFR Area
00’F200H
Segment 0
00’E800H
Area
SEGMENT 1 SEGMENT 1
00’FE00H
01’0000H
up to 3 KByte
IRAM
XPER/XRAM
Reserved
for XPERs
8 KByte
2 KB
XRAM Extension
00’A000H
Reserved
for
XRAM
Reserved
for
XFLASH
Compatible
Program
Reserved for
Memory
C165H
Memory Organization
Data Sheet 47 2001-04-19
PRELIMINARY
- EXCERPT -
Bytes are stored at even or odd byte addresses. Words are stored in ascending memory
locations with the low byte at an even byte address being followed by the high byte at
the next odd byte address. Double words (code only) are stored in ascending memory
locations as two subsequent words. Single bits are always stored in the specified bit
position at a word address. bit position 0 is the least significant bit of the byte at an even
byte address, and bit position 15 is the most significant bit of the byte at the next odd
byte address. bit addressing is supported for a part of the Special Function Registers, a
part of the internal RAM and for the General Purpose Registers.
Figure 9 Storage of Words, Byte and Bits in a Byte Organized Memory
Note: Byte units forming a single word or a double word must always be stored within
the same physical (internal, external, RAM) and organizational (page, segment)
memory area.
MCD01996
15 14 8
0
6
7
H
xxxx6
Bits
Bits
Byte
Byte
Word (High Byte)
Word (Low Byte)
xxxx5H
xxxx4H
xxxx3H
xxxx2H
xxxx1 H
xxxx0H
xxxxF H
C165H
Memory Organization
Data Sheet 48 2001-04-19
PRELIMINARY
- EXCERPT -
4.1 Internal RAM and SFR Area
The RAM/SFR area is located within data page 3 and provides access to the internal
RAM (IRAM, organized as X*16) and to two 512 Byte blocks of Special Function
Registers (SFRs). The C165H provides 3 KByte of IRAM, see Figure 10.
The internal RAM serves for several purposes:
• System Stack (programmable size)
• General Purpose Register Banks (GPRs)
• Source and destination pointers for the Peripheral Event Controller (PEC)
• Variable and other data storage, or
• Code storage.
Figure 10 Internal RAM Area and SFR Areas
System Segment 0
64 KByte
Area
ROM
Internal
Data Page 1
Data Page 0
00 0000H
’
00 4000
’H
External
Memory
Data Page 3
Data Page 2
00 8000
’H
00
00
00
00
E000
C000
’
’
H
H
F000
FFFF
’
’
H
H
RAM/SFR Area
4 KByte
ESFR Area
F200
F000
MCD02233
00’
00’
H
H
RAM
Internal
SFR Area
FE00
FFFF
00
RAM/SFR Area
’
00’
H
H
C165H
Memory Organization
Data Sheet 49 2001-04-19
PRELIMINARY
- EXCERPT -
Note: The upper 256 Bytes of SFR area, ESFR area and internal RAM are bit-
addressable (see shaded blocks in Figure 10).
Code accesses are always made on even byte addresses. The highest possible code
storage location in the internal RAM is either 00’FDFEH for single word instructions or
00’FDFCH for double word instructions. The respective location must contain a branch
instruction (unconditional), because sequential boundary crossing from internal RAM to
the SFR area is not supported and causes erroneous results.
Any word and byte data in the internal RAM can be accessed via indirect or long 16-bit
addressing modes, if the selected DPP register points to data page 3. Any word data
access is made on an even byte address. The highest possible word data storage
location in the internal RAM is 00’FDFEH. For PEC data transfers, the internal RAM can
be accessed independent of the contents of the DPP registers via the PEC source and
destination pointers.
The upper 256 Byte of the internal RAM (00’FD00H through 00’FDFFH) and the GPRs of
the current bank are provided for single bit storage, and thus they are bit addressable.
System Stack
The system stack may be defined within the internal RAM. The size of the system stack
is controlled by bitfield STKSZ in register SYSCON (see table below).
For all system stack operations the on-chip RAM is accessed via the Stack Pointer (SP)
register. The stack grows downward from higher towards lower RAM address locations.
Only word accesses are supported to the system stack. A stack overflow (STKOV) and
a stack underflow (STKUN) register are provided to control the lower and upper limits of
the selected stack area. These two stack boundary registers can be used not only for
protection against data destruction, but also allow to implement a circular stack with
hardware supported system stack flushing and filling (except for option ’111’).
The technique of implementing this circular stack is described in chapter “System
Programming”.
<STKSZ> Stack Size (Words) Internal RAM Addresses (Words)
0 0 0 B256 00’FBFEH...00’FA00H (Default after Reset)
0 0 1 B128 00’FBFEH...00’FB00H
0 1 0 B64 00’FBFEH...00’FB80H
0 1 1 B32 00’FBFEH...00’FBC0H
1 0 0 B512 00’FBFEH...00’F800H
1 0 1 B--- Reserved. Do not use this combination.
1 1 0 B--- Reserved. Do not use this combination.
1 1 1 B1024 00’FDFEH...00’F600H (Note: No circular stack)
C165H
Memory Organization
Data Sheet 50 2001-04-19
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General Purpose Registers
The General Purpose Registers (GPRs) use a block of 16 consecutive words within the
internal RAM. The Context Pointer (CP) register determines the base address of the
currently active register bank. This register bank may consist of up to 16 word GPRs (R0,
R1, ..., R15) and/or of up to 16 byte GPRs (RL0, RH0, ..., RL7, RH7). The sixteen byte
GPRs are mapped onto the first eight word GPRs (see table below).
In contrast to the system stack, a register bank grows from lower towards higher address
locations and occupies a maximum space of 32 Byte. The GPRs are accessed via short
2-, 4- or 8-bit addressing modes using the Context Pointer (CP) register as base address
(independent of the current DPP register contents). Additionally, each bit in the currently
active register bank can be accessed individually.
Mapping of General Purpose Registers to RAM Addresses
C165H supports fast register bank (context) switching. Multiple register banks can
physically exist within the internal RAM at the same time. Only the register bank selected
by the Context Pointer register (CP) is active at a given time, however. Selecting a new
active register bank is simply done by updating the CP register. A particular Switch
Context (SCXT) instruction performs register bank switching and an automatic saving of
the previous context. The number of implemented register banks (arbitrary sizes) is only
limited by the size of the available internal RAM.
Internal RAM Address Byte Registers Word Register
<CP> + 1EH--- R15
<CP> + 1CH--- R14
<CP> + 1AH--- R13
<CP> + 18H--- R12
<CP> + 16H--- R11
<CP> + 14H--- R10
<CP> + 12H--- R9
<CP> + 10H--- R8
<CP> + 0EHRH7 RL7 R7
<CP> + 0CHRH6 RL6 R6
<CP> + 0AHRH5 RL5 R5
<CP> + 08HRH4 RL4 R4
<CP> + 06HRH3 RL3 R3
<CP> + 04HRH2 RL2 R2
<CP> + 02HRH1 RL1 R1
<CP> + 00HRH0 RL0 R0
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Details on using, switching and overlapping register banks are described in chapter
“System Programming”.
PEC Source and Destination Pointers
The 16 word locations in the internal RAM from 00’FCE0H to 00’FCFEH (just below the
bit-addressable section) are provided as source and destination address pointers for
data transfers on the eight PEC channels. Each channel uses a pair of pointers stored
in two subsequent word locations with the source pointer (SRCPx) on the lower and the
destination pointer (DSTPx) on the higher word address (x = 7...0).
Figure 11 Location of the PEC Pointers
Whenever a PEC data transfer is performed, the pair of source and destination pointers,
which is selected by the specified PEC channel number, is accessed independent of the
current DPP register contents and also the locations referred to by these pointers are
accessed independent of the current DPP register contents. If a PEC channel is not
used, the corresponding pointer locations area available and can be used for word or
byte data storage.
For more details about the use of the source and destination pointers for PEC data
transfers see section “Interrupt and Trap Functions”.
00’FCE2
00’FCE0
H
H
SRCP0
DSTP0
00’F5FE
00’F600
MCD03903
H
H
Destination
00’FCFC
Pointers
and
H
PEC
Source
SRCP7
00’FCFE
H
DSTP7
Internal
00’FCE0
00’FCDE
RAM
H
H
00’FCFE
00’FD00
H
H
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Special Function Registers
The functions of the CPU, the bus interface, the I/O ports and the on-chip peripherals of
the C165H are controlled via a number of so-called Special Function Registers (SFRs).
These SFRs are arranged within two areas of 512 Byte size each. The first register block,
the SFR area, is located in the 512 Bytes above the internal RAM
(00’FFFFH...00’FE00H), the second register block, the Extended SFR (ESFR) area, is
located in the 512 Bytes below the internal RAM (00’F1FFH...00’F000H).
Special function registers can be addressed via indirect and long 16-bit addressing
modes. Using an 8-bit offset together with an implicit base address allows to address
word SFRs and their respective low bytes. However, this does not work for the
respective high bytes!
Note: Writing to any byte of an SFR causes the non-addressed complementary byte to
be cleared!
The upper half of each register block is bit-addressable, so the respective control/status
bits can directly be modified or checked using bit addressing.
When accessing registers in the ESFR area using 8-bit addresses or direct bit
addressing, an Extend Register (EXTR) instruction is required before, to switch the short
addressing mechanism from the standard SFR area to the Extended SFR area. This is
not required for 16-bit and indirect addresses. The GPRs R15...R0 are duplicated, ie.
they are accessible within both register blocks via short 2-, 4- or 8-bit addresses without
switching.
ESFR_SWITCH_EXAMPLE:
EXTR #4 ;Switch to ESFR area for next 4 instr.
MOV ODP2, #data16 ;ODP2 uses 8-bit reg addressing
BFLDL DP6, #mask, #data8 ;Bit addressing for bit fields
BSET DP1H.7 ;Bit addressing for single bits
MOV T8REL, R1 ;T8REL uses 16-bit mem address,
;R1 is duplicated into the ESFR space
;(EXTR is not required for this access)
;---- ;------------------- ;The scope of the EXTR #4 instruction...
;...ends here!
MOV T8REL, R1 ;T8REL uses 16-bit mem address,
;R1 is accessed via the SFR space
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In order to minimize the use of the EXTR instructions the ESFR area mostly holds
registers which are mainly required for initialization and mode selection. Registers that
need to be accessed frequently are allocated to the standard SFR area, wherever
possible.
Note: The tools are equipped to monitor accesses to the ESFR area and will
automatically insert EXTR instructions, or issue a warning in case of missing or
excessive EXTR instructions.
4.2 External Memory Space
The C165H is capable of using an address space of up to 8 MByte. Only parts of this
address space are occupied by internal memory areas. All addresses which are not used
for on-chip memory (RAM) or for registers may reference external memory locations.
This external memory is accessed via the C165H’s external bus interface.
Four memory bank sizes are supported:
• Non-segmented mode: 64 KByte with A15...A0 on PORT0 or PORT1
• 2-bit segmented mode: 256 KByte with A17...A16 on Port 4 and
A15...A0 on PORT0 or PORT1
• 4-bit segmented mode: 1 MByte with A19...A16 on Port 4 and
A15...A0 on PORT0 or PORT1
• 8-bit segmented mode: 8 MByte with A22...A16 on Port 4 and A15...A0 on PORT0 or
PORT1
Each bank can be directly addressed via the address bus, while the programmable chip
select signals can be used to select various memory banks.
The C165H also supports four different bus types:
• Multiplexed 16-bit Buswith address and data on PORT0 (Default after Reset)
• Multiplexed 8-bit Buswith address and data on PORT0/P0L
• Demultiplexed 16-bit Buswith address on PORT1 and data on PORT0
• Demultiplexed 8-bit Buswith address on PORT1 and data on P0L
Memory model and bus mode are selected during reset by pin EA and PORT0 pins. For
further details about the external bus configuration and control please refer to chapter
"The External Bus Interface".
External word and byte data can only be accessed via indirect or long 16-bit addressing
modes using one of the four DPP registers. There is no short addressing mode for
external operands. Any word data access is made to an even byte address.
For PEC data transfers the external memory can be accessed independent of the
contents of the DPP registers via the PEC source and destination pointers.
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The external memory is not provided for single bit storage and therefore it is not bit
addressable.
4.3 Crossing Memory Boundaries
The address space of the C165H is implicitly divided into equally sized blocks of different
granularity and into logical memory areas. Crossing the boundaries between these
blocks (code or data) or areas requires special attention to ensure that the controller
executes the desired operations.
Memory Areas are partitions of the address space that represent different kinds of
memory (if provided at all). These memory areas are the internal RAM/SFR area, the on-
chip X-Peripherals and the external memory.
Accessing subsequent data locations that belong to different memory areas is no
problem. However, when executing code, the different memory areas must be switched
explicitly via branch instructions. Sequential boundary crossing is not supported and
leads to erroneous results.
Note: Changing from the external memory area to the internal RAM/SFR area takes
place within segment 0.
Segments are contiguous blocks of 64 KByte each. They are referenced via the code
segment pointer CSP for code fetches and via an explicit segment number for data
accesses overriding the standard DPP scheme.
During code fetching segments are not changed automatically, but rather must be
switched explicitly. The instructions JMPS, CALLS and RETS will do this.
In larger sequential programs make sure that the highest used code location of a
segment contains an unconditional branch instruction to the respective following
segment, to prevent the prefetcher from trying to leave the current segment.
Data Pages are contiguous blocks of 16 KByte each. They are referenced via the data
page pointers DPP3...0 and via an explicit data page number for data accesses
overriding the standard DPP scheme. Each DPP register can select one of the possible
1024 data pages. The DPP register that is used for the current access is selected via the
two upper bits of the 16-bit data address. Subsequent 16-bit data addresses that cross
the 16 KByte data page boundaries therefore will use different data page pointers, while
the physical locations need not be subsequent within memory.
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5 Central Processor Unit
Basic tasks of the CPU are to fetch and decode instructions, to supply operands for the
arithmetic and logic unit (ALU), to perform operations on these operands in the ALU, and
to store the previously calculated results. As the CPU is the main engine of the C165H
controller, it is also affected by certain actions of the peripheral subsystem.
Since a four stage pipeline is implemented in the C165H, up to four instructions can be
processed in parallel. Most instructions of the C165H are executed in one machine cycle
(2 CPU clock cycles) due to this parallelism. This chapter describes how the pipeline
works for sequential and branch instructions in general, and which hardware provisions
have been made to speed the execution of jump instructions in particular. The general
instruction timing is described including standard and exceptional timing.
While internal memory accesses are normally performed by the CPU itself, external
peripheral or memory accesses are performed by a particular on-chip External Bus
Controller (EBC), which is automatically invoked by the CPU whenever a code or data
address refers to the external address space. If possible, the CPU continues operating
while an external memory access is in progress. If external data are required but are not
yet available, or if a new external memory access is requested by the CPU, before a
previous access has been completed, the CPU will be held by the EBC until the request
can be satisfied. The EBC is described in a dedicated chapter.
Figure 12 CPU Block Diagram
MCB02147
CPU
SP
STKOV
STKUN
Instr. Reg.
Instr. Ptr.
Exec. Unit
4-Stage
Pipeline
MDH
MDL
PSW
SYSCON Context Ptr.
Mul/Div-HW
R15
R0
General
Purpose
Registers
Bit-Mask Gen
Barrel - Shifter
ALU
(16-bit)
Data Page Ptr. Code Seg. Ptr.
Internal
RAM
R15
R0
ROM
16
16
32
BUSCON 0
BUSCON 1
BUSCON 2
BUSCON 3
BUSCON 4 ADDRSEL 4
ADDRSEL 3
ADDRSEL 2
ADDRSEL 1
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The on-chip peripheral units of the C165H work nearly independent of the CPU with a
separate clock generator. Data and control information is interchanged between the
CPU and these peripherals via Special Function Registers (SFRs). Whenever
peripherals need a non-deterministic CPU action, an on-chip Interrupt Controller
compares all pending peripheral service requests against each other and prioritizes one
of them. If the priority of the current CPU operation is lower than the priority of the
selected peripheral request, an interrupt will occur.
Basically, there are two types of interrupt processing:
•Standard interrupt processing forces the CPU to save the current program status
and the return address on the stack before branching to the interrupt vector jump
table.
•PEC interrupt processing steals just one machine cycle from the current CPU
activity to perform a single data transfer via the on-chip Peripheral Event Controller
(PEC).
System errors detected during program execution (socalled hardware traps) or an
external non-maskable interrupt are also processed as standard interrupts with a very
high priority.
In contrast to other on-chip peripherals, there is a closer conjunction between the
watchdog timer and the CPU. If enabled, the watchdog timer expects to be serviced by
the CPU within a programmable period of time, otherwise it will reset the chip. Thus, the
watchdog timer is able to prevent the CPU from going totally astray when executing
erroneous code. After reset, the watchdog timer starts counting automatically, but it can
be disabled via software, if desired.
Beside its normal operation there are the following particular CPU states:
•Reset state: Any reset (hardware, software, watchdog) forces the CPU into a
predefined active state.
•IDLE state: The clock signal to the CPU itself is switched off, while the clocks for the
on-chip peripherals keep running.
•POWER DOWN state: All of the on-chip clocks are switched off.
A transition into an active CPU state is forced by an interrupt (if being IDLE) or by a reset
(if being in POWER DOWN mode).
The IDLE, POWER DOWN and RESET states can be entered by particular C165H
system control instructions.
A set of Special Function Registers is dedicated to the functions of the CPU core:
• General System Configuration: SYSCON (RP0H)
• CPU Status Indication and Control: PSW
• Code Access Control: IP, CSP
• Data Paging Control: DPP0, DPP1, DPP2, DPP3
• GPRs Access Control: CP
• System Stack Access Control: SP, STKUN, STKOV
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• Multiply and Divide Support: MDL, MDH, MDC
• ALU Constants Support: ZEROS, ONES
5.1 Instruction Pipelining
The instruction pipeline of the C165H partitiones instruction processing into four stages
of which each one has its individual task:
1st –>FETCH:
In this stage the instruction selected by the Instruction Pointer (IP) and the Code
Segment Pointer (CSP) is fetched from either the internal RAM, or external memory.
2nd –>DECODE:
In this stage the instructions are decoded and, if required, the operand addresses are
calculated and the respective operands are fetched. For all instructions, which implicitly
access the system stack, the SP register is either decremented or incremented, as
specified. For branch instructions the Instruction Pointer and the Code Segment Pointer
are updated with the desired branch target address (provided that the branch is taken).
3rd –>EXECUTE:
In this stage an operation is performed on the previously fetched operands in the ALU.
Additionally, the condition flags in the PSW register are updated as specified by the
instruction. All explicit writes to the SFR memory space and all auto-increment or auto-
decrement writes to GPRs used as indirect address pointers are performed during the
execute stage of an instruction, too.
4th –>WRITE BACK:
In this stage all external operands and the remaining operands within the internal RAM
space are written back.
A particularity of the C165H are the so-called injected instructions. These injected
instructions are generated internally by the machine to provide the time needed to
process instructions, which cannot be processed within one machine cycle. They are
automatically injected into the decode stage of the pipeline, and then they pass through
the remaining stages like every standard instruction. Program interrupts are performed
by means of injected instructions, too. Although these internally injected instructions will
not be noticed in reality, they are introduced here to ease the explanation of the pipeline
in the following.
Sequential Instruction Processing
Each single instruction has to pass through each of the four pipeline stages regardless
of whether all possible stage operations are really performed or not. Since passing
through one pipeline stage takes at least one machine cycle, any isolated instruction
takes at least four machine cycles to be completed. Pipelining, however, allows parallel
(ie. simultaneous) processing of up to four instructions. Thus, most of the instructions
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seem to be processed during one machine cycle as soon as the pipeline has been filled
once after reset (see figure below).
Instruction pipelining increases the average instruction throughput considered over a
certain period of time. In the following, any execution time specification of an instruction
always refers to the average execution time due to pipelined parallel instruction
processing.
Figure 13 Sequential Instruction Pipelining
Standard Branch Instruction Processing
Instruction pipelining helps to speed sequential program processing. In the case that a
branch is taken, the instruction which has already been fetched providently is mostly not
the instruction which must be decoded next. Thus, at least one additional machine cycle
is normally required to fetch the branch target instruction. This extra machine cycle is
provided by means of an injected instruction (see Figure 14).
Figure 14 Standard Branch Instruction Pipelining
1 Machine
Cycle
FETCH I2
I1
I3
I2
I1
I4
I3
I2
I1
I6
I5
I4
I3
I5
I4
I3
I2
I1
DECODE
EXECUTE
WRITEBACK
time
1 Machine
Cycle
FETCH In+2
BRANCH
In
. . .
ITARGET
(IINJECT)
BRANCH
In
ITARGET+1
ITARGET
(IINJECT)
BRANCH
ITARGET+3
ITARGET+2
ITARGET+1
ITARGET
ITARGET+2
ITARGET+1
ITARGET
(IINJECT)
BRANCH
In
. . .
. . .
DECODE
EXECUTE
WRITEBACK
time
Injection
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If a conditional branch is not taken, there is no deviation from the sequential program
flow, and thus no extra time is required. In this case the instruction after the branch
instruction will enter the decode stage of the pipeline at the beginning of the next
machine cycle after decode of the conditional branch instruction.
Cache Jump Instruction Processing
The C165H incorporates a jump cache to optimize conditional jumps, which are
processed repeatedly within a loop. Whenever a jump on cache is taken, the extra time
to fetch the branch target instruction can be saved and thus the corresponding cache
jump instruction in most cases takes only one machine cycle.
This performance is achieved by the following mechanism:
Whenever a cache jump instruction passes through the decode stage of the pipeline for
the first time (and provided that the jump condition is met), the jump target instruction is
fetched as usual, causing a time delay of one machine cycle. In contrast to standard
branch instructions, however, the target instruction of a cache jump instruction (JMPA,
JMPR, JB, JBC, JNB, JNBS) is additionally stored in the cache after having been
fetched.
After each repeatedly following execution of the same cache jump instruction, the jump
target instruction is not fetched from progam memory but taken from the cache and
immediatly injected into the decode stage of the pipeline (see Figure 15).
A time saving jump on cache is always taken after the second and any further occurrence
of the same cache jump instruction, unless an instruction which, has the fundamental
capability of changing the CSP register contents (JMPS, CALLS, RETS, TRAP, RETI),
or any standard interrupt has been processed during the period of time between two
following occurrences of the same cache jump instruction.
Figure 15 Cache Jump Instruction Pipelining
In+2
Cache Jmp
In
. . .
ITARGET+1
ITARGET
Cache Jmp
In
ITARGET+2
ITARGET+1
ITARGET
Cache Jmp
In+2
Cache Jmp
In
. . .
ITARGET
(IINJECT)
Cache Jmp
In
ITARGET+1
ITARGET
(IINJECT)
Cache Jmp
1 Machine
Cycle
FETCH
DECODE
EXECUTE
WRITEBACK
1st loop iteration
Injection Injection of cached
Target Instruction
Repeated loop iteration
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Particular Pipeline Effects
Since up to four different instructions are processed simultaneously, additional hardware
has been spent in the C165H to consider all causal dependencies which may exist on
instructions in different pipeline stages without a loss of performance. This extra
hardware (ie. for 'forwarding' operand read and write values) resolves most of the
possible conflicts (eg. multiple usage of buses) in a time optimized way and thus avoids
that the pipeline becomes noticeable for the user in most cases. However, there are
some very rare cases, where the circumstance that the C165H is a pipelined machine
requires attention by the programmer. In these cases the delays caused by pipeline
conflicts can be used for other instructions in order to optimize performance.
• Context Pointer Updating
An instruction, which calculates a physical GPR operand address via the CP register, is
mostly not capable of using a new CP value, which is to be updated by an immediately
preceding instruction. Thus, to make sure that the new CP value is used, at least one
instruction must be inserted between a CP-changing and a subsequent GPR-using
instruction, as shown in the following example:
In: SCXT CP, #0FC00h ; select a new context
In+1 : .... ; must not be an instruction using a GPR
In+2 : MOV R0, #dataX ; write to GPR 0 in the new context
• Data Page Pointer Updating
An instruction, which calculates a physical operand address via a particular DPPn (n=0
to 3) register, is mostly not capable of using a new DPPn register value, which is to be
updated by an immediately preceding instruction. Thus, to make sure that the new DPPn
register value is used, at least one instruction must be inserted between a DPPn-
changing instruction and a subsequent instruction which implicitly uses DPPn via a long
or indirect addressing mode, as shown in the following example:
In: MOV DPP0, #4 ; select data page 4 via DPP0
In+1 : .... ; must not be an instruction using DPP0
In+2 : MOV DPP0:0000H, R1 ; move contents of R1 to address location 01’0000H
; (in data page 4) supposed segmentation is enabled
• Explicit Stack Pointer Updating
None of the RET, RETI, RETS, RETP or POP instructions is capable of correctly using
a new SP register value, which is to be updated by an immediately preceding instruction.
Thus, in order to use the new SP register value without erroneously performed stack
accesses, at least one instruction must be inserted between an explicitly SP-writing and
any subsequent of the just mentioned implicitly SP-using instructions, as shown in the
following example:
In: MOV SP, #0FA40H ; select a new top of stack
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In+1 : .... ; must not be an instruction popping operands
; from the system stack
In+2 : POP R0 ; pop word value from new top of stack into R0
Note: Conflicts with instructions writing to the stack (PUSH, CALL, SCXT) are solved
internally by the CPU logic.
• External Memory Access Sequences
The effect described here will only become noticeable, when watching the external
memory access sequences on the external bus (eg. by means of a Logic Analyzer).
Different pipeline stages can simultaneously put a request on the External Bus Controller
(EBC). The sequence of instructions processed by the CPU may diverge from the
sequence of the corresponding external memory accesses performed by the EBC, due
to the predefined priority of external memory accesses:
1st Write Data
2nd Fetch Code
3rd Read Data.
• Controlling Interrupts
Software modifications (implicit or explicit) of the PSW are done in the execute phase of
the respective instructions. In order to maintain fast interrupt responses, however, the
current interrupt prioritization round does not consider these changes, ie. an interrupt
request may be acknowledged after the instruction that disables interrupts via IEN or
ILVL or after the following instructions. Timecritical instruction sequences therefore
should not begin directly after the instruction disabling interrupts, as shown in the
following example:
INT_OFF: BCLR IEN ; globally disable interrupts
IN-1 ; non-critical instruction
CRIT_1ST: IN; begin of uninterruptable critical sequence
. . .
CRIT_LAST: IN+x ; end of uninterruptable critical sequence
INT_ON: BSET IEN ; globally re-enable interrupts
Note: The described delay of 1 instruction also applies for enabling the interrupts system
ie. no interrupt requests are acknowledged until the instruction following the
enabling instruction.
• Initialization of Port Pins
Modifications of the direction of port pins (input or output) become effective only after the
instruction following the modifying instruction. As bit instructions (BSET, BCLR) use
internal read-modify-write sequences accessing the whole port, instructions modifying
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the port direction should be followed by an instruction that does not access the same port
(see example below).
WRONG: BSET DP3.13 ; change direction of P3.13 to output
BSET P3.5 ; P3.13 is still input, the rd-mod-wr reads pin P3.13
RIGHT: BSET DP3.13 ; change direction of P3.13 to output
NOP ; any instruction not accessing port 3
BSET P3.5 ; P3.13 is now output,
; the rd-mod-wr reads the P3.13 output latch
• Changing the System Configuration
The instruction following an instruction that changes the system configuration via register
SYSCON (eg. segmentation, stack size) cannot use the new resources (eg. stack). In
these cases an instruction that does not access these resources should be inserted.
• BUSCON/ADDRSEL
The instruction following an instruction that changes the properties of an external
address area cannot access operands within the new area. In these cases an instruction
that does not access this address area should be inserted. Code accesses to the new
address area should be made after an absolute branch to this area.
Note: As a rule, instructions that change external bus properties should not be executed
from the respective external memory area.
• Timing
Instruction pipelining reduces the average instruction processing time in a wide scale
(from four to one machine cycles, mostly). However, there are some rare cases, where
a particular pipeline situation causes the processing time for a single instruction to be
extended either by a half or by one machine cycle. Although this additional time
represents only a tiny part of the total program execution time, it might be of interest to
avoid these pipeline-caused time delays in time critical program modules.
Besides a general execution time description, the following section provides some hints
on how to optimize time-critical program parts with regard to such pipeline-caused timing
particularities.
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5.2 Bit-Handling and Bit-Protection
The C165H provides several mechanisms to manipulate bits. These mechanisms either
manipulate software flags within the internal RAM, control on-chip peripherals via control
bits in their respective SFRs or control I/O functions via port pins.
The instructions BSET, BCLR, BAND, BOR, BXOR, BMOV, BMOVN explicitly set or
clear specific bits. The instructions BFLDL and BFLDH allow to manipulate up to 8 bits
of a specific byte at one time. The instructions JBC and JNBS implicitly clear or set the
specified bit when the jump is taken. The instructions JB and JNB (also conditional jump
instructions that refer to flags) evaluate the specified bit to determine if the jump is to be
taken.
Note: Bit operations on undefined bit locations will always read a bit value of ‘0’, while
the write access will not effect the respective bit location.
All instructions that manipulate single bits or bit groups internally use a read-modify-write
sequence that accesses the whole word, which contains the specified bit(s).
This method has several consequences:
• Bits can only be modified within the internal address areas, ie. internal RAM and SFRs.
External locations cannot be used with bit instructions.
The upper 256 bytes of the SFR area, the ESFR area and the internal RAM are bit-
addressable (see chapter “Memory Organization”), ie. those register bits located within
the respective sections can be directly manipulated using bit instructions. The other
SFRs must be accessed byte/word wise.
Note: All GPRs are bit-addressable independent of the allocation of the register bank via
the context pointer CP. Even GPRs which are allocated to not bit-addressable
RAM locations provide this feature.
• The read-modify-write approach may be critical with hardware-effected bits. In these
cases the hardware may change specific bits while the read-modify-write operation is in
progress, where the writeback would overwrite the new bit value generated by the
hardware. The solution is either the implemented hardware protection (see below) or
realized through special programming (see “Particular Pipeline Effects”).
Protected bits are not changed during the read-modify-write sequence, ie. when
hardware sets eg. an interrupt request flag between the read and the write of the read-
modify-write sequence. The hardware protection logic guarantees that only the intended
bit(s) is/are effected by the write-back operation.
Note: If a conflict occurs between a bit manipulation generated by hardware and an
intended software access the software access has priority and determines the
final value of the respective bit.
A summary of the protected bits implemented in the C165H can be found at the end of
chapter “Architectural Overview”.
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5.3 Instruction State Times
Basically, the time to execute an instruction depends on where the instruction is fetched
from, and where possible operands are read from or written to. The fastest processing
mode of the C165H is to execute a program fetched from the internal code memory. In
that case most of the instructions can be processed within just one machine cycle, which
is also the general minimum execution time.
All external memory accesses are performed by the C165H’s on-chip External Bus
Controller (EBC), which works in parallel with the CPU.
This section summarizes the execution times in a very condensed way. A detailled
description of the execution times for the various instructions and the specific exceptions
can be found in the “C16x Family Instruction Set Manual”.
The table below shows the minimum execution times required to process a C165H
instruction fetched from the internal RAM or from external memory. These execution
times apply to most of the C165H instructions - except some of the branches, the
multiplication, the division and a special move instruction. The numbers in the table are
in units of [ns], refer to a CPU clock of 20 MHz and assume no waitstates.
Table 10 Minimum Execution Times
Execution from the internal RAM provides flexibility in terms of loadable and modifyable
code on the account of execution time.
Execution from external memory strongly depends on the selected bus mode and the
programming of the bus cycles (waitstates).
The operand and instruction accesses listed below can extend the execution time of an
instruction:
• Internal RAM operand reads via indirect addressing modes
• Internal SFR operand reads immediately after writing
• External operand reads
• External operand writes
Instruction Fetch Word Operand Access
Memory Area Word
Instruction
Doubleword
Instruction
Read from Write to
Internal RAM 6 8 0/1 0
16-bit Demux Bus 2 4 2 2
16-bit Mux Bus 3 6 3 3
8-bit Demux Bus 4 8 4 4
8-bit Mux Bus 6 12 6 6
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• Jumps to non-aligned double word instructions in the internal ROM space
• Testing Branch Conditions immediately after PSW writes
5.4 CPU Special Function Registers
The core CPU requires a set of Special Function Registers (SFRs) to maintain the
system state information, to supply the ALU with register-addressable constants and to
control system and bus configuration, multiply and divide ALU operations, code memory
segmentation, data memory paging, and accesses to the General Purpose Registers
and the System Stack.
The access mechanism for these SFRs in the CPU core is identical to the access
mechanism for any other SFR. Since all SFRs can simply be controlled by means of any
instruction, which is capable of addressing the SFR memory space, a lot of flexibility has
been gained, without the need to create a set of system-specific instructions.
Note, however, that there are user access restrictions for some of the CPU core SFRs
to ensure proper processor operations. The instruction pointer IP and code segment
pointer CSP cannot be accessed directly at all. They can only be changed indirectly via
branch instructions.
The PSW, SP, and MDC registers can be modified not only explicitly by the programmer,
but also implicitly by the CPU during normal instruction processing. Note that any explicit
write request (via software) to an SFR supersedes a simultaneous modification by
hardware of the same register.
Note: Any write operation to a single byte of an SFR clears the non-addressed
complementary byte within the specified SFR.
Non-implemented (reserved) SFR bits cannot be modified, and will always supply
a read value of '0'.
The System Configuration Register SYSCON
This bit-addressable register provides general system configuration and control
functions. The reset value for register SYSCON depends on the state of the PORT0 pins
during reset (see hardware effectable bits).
C165H
Central Processor Unit
Data Sheet 66 2001-04-19
PRELIMINARY
- EXCERPT -
SYSCON (FF12H / 89H) SFR Reset Value: 0XX0H
Bit Function
XPER-SHARE Reserved
The XPER-SHARE mode, known from other C16x Infineon derivatives, is not
supported in the C165H. This bit must be set to ’0’ signal.
VISIBLE Visible Mode Control
’0’: Accesses to XBUS peripherals are done internally
’1’: XBUS peripheral accesses are made visible on the external pins
XPEN XBUS Peripheral Enable Bit
’0’: Accesses to the on-chip X-Peripherals and their functions are disabled
’1’: The on-chip X-Peripherals are enabled and can be accessed
Note: This bit is valid only for derivatives that contain X-Peripherals.
OSCENBL Oscillator Watchdog Enable Bit
‘0’: The oscillator watchdog is disabled. Default configuration.
‘1’: The oscillator watchdog is enabled.
CSCFG Chip Select Configuration Control
‘0’: Latched CS mode. The CS signals are latched internally and driven to the
enabled port pins synchronously.
‘1’: Unlatched CS mode. The CS signals are directly derived from the address
and driven to the enabled port pins.
WRCFG Write Configuration Control (Set according to pin P0H.0 during reset)
’0’:Pins WR
and BHE retain their normal function
’1’:Pin WR
acts as WRL, pin BHE acts as WRH
CLKEN System Clock Output Enable (CLKOUT)
’0’: CLKOUT disabled: pin may be used for general purpose I/O
’1’: CLKOUT enabled: pin outputs the system clock signal
BYTDIS Disable/Enable Control for Pin BHE (Set according to data bus width)
’0’:Pin BHE
enabled
’1’:Pin BHE
disabled, pin may be used for general purpose I/O
ROMEN Internal Boot-ROM Enable
’0’: Internal Boot-ROM is disabled. Access of the lower 32k address space will
be linked to external memory. During normal operation, bit ROMEN must
always be set to ’0’ signal
’1’: Internal Boot-ROM is enabled. This bit is only set in BSL mode.
Note: During BSL mode, if the lowest 32k of external memory needs to be
programmed, bit ROMEN must be set to ’0’ signal.
After BSL mode, make sure that bit ROMEN is cleared.
XPEN XPER-
SHARE
VISI
BLE
- -
ROM
S1 WR
CFG
54321011 10 987615 14 13 12
- - rwrw rw rwrw rw
STKSZ SGT
DIS ROM
EN
rw
BYT
DIS CLK
EN
rw rw rw rwrw
OSC
ENBL
CS
CFG
C165H
Central Processor Unit
Data Sheet 67 2001-04-19
PRELIMINARY
- EXCERPT -
Note: Register SYSCON cannot be changed after execution of the EINIT instruction.
System Clock Output Enable (CLKEN)
The system clock output function is enabled by setting bit CLKEN in register SYSCON
to '1'. If enabled, port pin P3.15 takes on its alternate function as CLKOUT output pin.
The clock output is a 50 % duty cycle clock whose frequency equals the CPU operating
frequency (fOUT = fCPU).
Note: The output driver of port pin P3.15 is switched on automatically, when the
CLKOUT function is enabled. The port direction bit is disregarded.
After reset, the clock output function is disabled (CLKEN = ‘0’).
Segmentation Disable/Enable Control (SGTDIS)
Bit SGTDIS allows to select either the segmented or non-segmented memory mode.
In non-segmented memory mode (SGTDIS='1') it is assumed that the code address
space is restricted to 64 KBytes (segment 0) and thus 16 bits are sufficient to represent
all code addresses. For implicit stack operations (CALL or RET) the CSP register is
totally ignored and only the IP is saved to and restored from the stack.
In segmented memory mode (SGTDIS='0') it is assumed that the whole address space
is available for instructions. For implicit stack operations (CALL or RET) the CSP register
and the IP are saved to and restored from the stack. After reset the segmented memory
mode is selected.
Note: Bit SGTDIS controls if the CSP register is pushed onto the system stack in addition
to the IP register before an interrupt service routine is entered, and it is repopped
when the interrupt service routine is left again.
SGTDIS Segmentation Disable/Enable Control
’0’: Segmentation enabled
(CSP and IP are saved/restored during interrupt entry/exit)
’1’: Segmentation disabled (Only IP is saved/restored)
ROMS1 Reserved
The ROMS1, known from other C16x Infineon derivatives, is not supported in
the C165H. This bit must be set to ’0’ signal.
STKSZ System Stack Size
Selects the size of the system stack (in the internal RAM) from 32 to 1024 words
Bit Function
C165H
Central Processor Unit
Data Sheet 68 2001-04-19
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- EXCERPT -
System Stack Size (STKSZ)
This bitfield defines the size of the physical system stack, which is located in the internal
RAM of the C165H. An area of 32...512 words or all of the internal RAM may be
dedicated to the system stack. A so-called “circular stack” mechanism allows to use a
bigger virtual stack than this dedicated RAM area.
These techniques as well as the encoding of bitfield STKSZ are described in more detail
in chapter “System Programming”.
The Processor Status Word PSW
This bit-addressable register reflects the current state of the microcontroller. Two groups
of bits represent the current ALU status, and the current CPU interrupt status. A separate
bit (USR0) within register PSW is provided as a general purpose user flag.
PSW (FF10H / 88H) SFR Reset Value: 0000H
ALU Status (N, C, V, Z, E, MULIP)
The condition flags (N, C, V, Z, E) within the PSW indicate the ALU status due to the last
recently performed ALU operation. They are set by most of the instructions due to
specific rules, which depend on the ALU or data movement operation performed by an
instruction.
After execution of an instruction which explicitly updates the PSW register, the condition
flags cannot be interpreted as described in the following, because any explicit write to
the PSW register supersedes the condition flag values, which are implicitly generated by
the CPU. Explicitly reading the PSW register supplies a read value which represents the
state of the PSW register after execution of the immediately preceding instruction.
Note: After reset, all of the ALU status bits are cleared.
• N-Flag: For most of the ALU operations, the N-flag is set to '1', if the most significant
bit of the result contains a '1', otherwise it is cleared. In the case of integer operations the
N-flag can be interpreted as the sign bit of the result (negative: N=’1’, positive: N=’0’).
Negative numbers are always represented as the 2's complement of the corresponding
positive number. The range of signed numbers extends from '–8000H' to '+7FFFH' for the
word data type, or from '–80H' to '+7FH' for the byte data type.For Boolean bit operations
with only one operand the N-flag represents the previous state of the specified bit. For
Boolean bit operations with two operands the N-flag represents the logical XORing of the
two specified bits.
HLD
EN MUL
IP
USR0- NZCVE
54321011 10 987615 14 13 12
rw rw rw rw-rw rw rw-rw -rw
IEN --
ILVL
rw
C165H
Central Processor Unit
Data Sheet 69 2001-04-19
PRELIMINARY
- EXCERPT -
• C-Flag: After an addition the C-flag indicates that a carry from the most significant bit
of the specified word or byte data type has been generated. After a subtraction or a
comparison the C-flag indicates a borrow, which represents the logical negation of a
carry for the addition.
This means that the C-flag is set to '1', if no carry from the most significant bit of the
specified word or byte data type has been generated during a subtraction, which is
performed internally by the ALU as a 2's complement addition, and the C-flag is cleared
when this complement addition caused a carry.
The C-flag is always cleared for logical, multiply and divide ALU operations, because
these operations cannot cause a carry anyhow.
For shift and rotate operations the C-flag represents the value of the bit shifted out last.
If a shift count of zero is specified, the C-flag will be cleared. The C-flag is also cleared
for a prioritize ALU operation, because a '1' is never shifted out of the MSB during the
normalization of an operand.
For Boolean bit operations with only one operand the C-flag is always cleared. For
Boolean bit operations with two operands the C-flag represents the logical ANDing of the
two specified bits.
• V-Flag: For addition, subtraction and 2's complementation the V-flag is always set to
'1', if the result overflows the maximum range of signed numbers, which are
representable by either 16 bits for word operations ('–8000H' to '+7FFFH'), or by 8 bits for
byte operations ('–80H' to '+7FH'), otherwise the V-flag is cleared. Note that the result of
Bit Function
N Negative Result
Set, when the result of an ALU operation is negative.
C Carry Flag
Set, when the result of an ALU operation produces a carry bit.
V Overflow Result
Set, when the result of an ALU operation produces an overflow.
Z Zero Flag
Set, when the result of an ALU operation is zero.
E End of Table Flag
Set, when the source operand of an instruction is 8000H or 80H.
MULIP Multiplication/Division In Progress
‘0’: There is no multiplication/division in progress.
‘1’: A multiplication/division has been interrupted.
USR0 User General Purpose Flag
May be used by the application software.
HLDEN,
ILVL, IEN
Interrupt and EBC Control Fields
Define the response to interrupt requests and enable external bus arbitration.
(Described in section “Interrupt and Trap Functions”)
C165H
Central Processor Unit
Data Sheet 70 2001-04-19
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- EXCERPT -
an integer addition, integer subtraction, or 2's complement is not valid, if the V-flag
indicates an arithmetic overflow.
For multiplication and division the V-flag is set to '1', if the result cannot be represented
in a word data type, otherwise it is cleared. Note that a division by zero will always cause
an overflow. In contrast to the result of a division, the result of a multiplication is valid
regardless of whether the V-flag is set to '1' or not.
Since logical ALU operations cannot produce an invalid result, the V-flag is cleared by
these operations.
The V-flag is also used as 'Sticky Bit' for rotate right and shift right operations. With only
using the C-flag, a rounding error caused by a shift right operation can be estimated up
to a quantity of one half of the LSB of the result. In conjunction with the V-flag, the C-flag
allows evaluating the rounding error with a finer resolution (see table below).
For Boolean bit operations with only one operand the V-flag is always cleared. For
Boolean bit operations with two operands the V-flag represents the logical ORing of the
two specified bits.
Table 11 Shift Right Rounding Error Evaluation
• Z-Flag: The Z-flag is normally set to '1', if the result of an ALU operation equals zero,
otherwise it is cleared.
For the addition and subtraction with carry the Z-flag is only set to '1', if the Z-flag already
contains a '1' and the result of the current ALU operation additionally equals zero. This
mechanism is provided for the support of multiple precision calculations.
For Boolean bit operations with only one operand the Z-flag represents the logical
negation of the previous state of the specified bit. For Boolean bit operations with two
operands the Z-flag represents the logical NORing of the two specified bits. For the
prioritize ALU operation the Z-flag indicates, if the second operand was zero or not.
• E-Flag: The E-flag can be altered by instructions, which perform ALU or data
movement operations. The E-flag is cleared by those instructions which cannot be
reasonably used for table search operations. In all other cases the E-flag is set
depending on the value of the source operand to signify whether the end of a search
table is reached or not. If the value of the source operand of an instruction equals the
lowest negative number, which is representable by the data format of the corresponding
instruction ('8000H' for the word data type, or '80H' for the byte data type), the E-flag is
set to '1', otherwise it is cleared.
C-Flag V-Flag Rounding Error Quantity
0
0
1
1
0
1
0
1
- No rounding error -
0 < Rounding error < 1/2 LSB
Rounding error = 1/2 LSB
Rounding error > 1/2 LSB
C165H
Central Processor Unit
Data Sheet 71 2001-04-19
PRELIMINARY
- EXCERPT -
• MULIP-Flag: The MULIP-flag will be set to '1' by hardware upon the entrance into an
interrupt service routine, when a multiply or divide ALU operation was interrupted before
completion. Depending on the state of the MULIP bit, the hardware decides whether a
multiplication or division must be continued or not after the end of an interrupt service.
The MULIP bit is overwritten with the contents of the stacked MULIP-flag when the
return-from-interrupt-instruction (RETI) is executed. This normally means that the
MULIP-flag is cleared again after that.
Note: The MULIP flag is a part of the task environment! When the interrupting service
routine does not return to the interrupted multiply/divide instruction (ie. in case of
a task scheduler that switches between independent tasks), the MULIP flag must
be saved as part of the task environment and must be updated accordingly for the
new task before this task is entered.
CPU Interrupt Status (IEN, ILVL)
The Interrupt Enable bit allows to globally enable (IEN=’1’) or disable (IEN=’0’) interrupts.
The four-bit Interrupt Level field (ILVL) specifies the priority of the current CPU activity.
The interrupt level is updated by hardware upon entry into an interrupt service routine,
but it can also be modified via software to prevent other interrupts from being
acknowledged. In case an interrupt level '15' has been assigned to the CPU, it has the
highest possible priority, and thus the current CPU operation cannot be interrupted
except by hardware traps or external non-maskable interrupts. For details please refer
to chapter “Interrupt and Trap Functions”.
After reset all interrupts are globally disabled, and the lowest priority (ILVL=0) is
assigned to the initial CPU activity.
The Instruction Pointer IP
This register determines the 16-bit intra-segment address of the currently fetched
instruction within the code segment selected by the CSP register. The IP register is not
mapped into the C165H's address space, and thus it is not directly accessable by the
programmer. The IP can, however, be modified indirectly via the stack by means of a
return instruction.
The IP register is implicitly updated by the CPU for branch instructions and after
instruction fetch operations.
C165H
Central Processor Unit
Data Sheet 72 2001-04-19
PRELIMINARY
- EXCERPT -
IP (---- / --) --- Reset Value: 0000H
The Code Segment Pointer CSP
This non-bit addressable register selects the code segment being used at run-time to
access instructions. The lower 8 bits of register CSP select one of up to 256 segments
of 64 KBytes each, while the upper 8 bits are reserved for future use.
CSP (FE08H / 04H) SFR Reset Value: 0000H
Code memory addresses are generated by directly extending the 16-bit contents of the
IP register by the contents of the CSP register as shown in the figure below.
In case of the segmented memory mode the selected number of segment address bits
(via bitfield SALSEL) of register CSP is output on the respective segment address pins
of Port 4 for all external code accesses. For non-segmented memory mode or Single
Chip Mode the content of this register is not significant, because all code acccesses are
automatically restricted to segment 0.
Note: The CSP register can only be read but not written by data operations. It is,
however, modified either directly by means of the JMPS and CALLS instructions,
or indirectly via the stack by means of the RETS and RETI instructions.
Upon the acceptance of an interrupt or the execution of a software TRAP
instruction, the CSP register is automatically set to zero.
Bit Function
ip Specifies the intra segment offset, from where the current instruction is to be
fetched. IP refers to the current segment <SEGNR>.
Bit Function
SEGNR Segment Number
Specifies the code segment, from where the current instruction is to be fetched.
SEGNR is ignored, when segmentation is disabled.
54321011 10 987615 14 13 12
(r)(w)
ip
- ----
54321011 10 987615 14 13 12
- - - r-- --
---
-
SEGNR
C165H
Central Processor Unit
Data Sheet 73 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 16 Addressing via the Code Segment Pointer
Note: When segmentation is disabled, the IP value is used directly as the 16-bit address.
Data Page Pointers DPP0, DPP1, DPP2, DPP3
These four non-bit addressable registers select up to four different data pages being
active simultaneously at run-time. The lower 10 bits of each DPP register select one of
the 1024 possible 16-Kbyte data pages while the upper 6 bits are reserved for future use.
The DPP registers allow to access the entire memory space in pages of 16 Kbytes each.
The DPP registers are implicitly used, whenever data accesses to any memory location
are made via indirect or direct long 16-bit addressing modes (except for override
accesses via EXTended instructions and PEC data transfers). After reset, the Data Page
Pointers are initialized in a way that all indirect or direct long 16-bit addresses result in
identical 18-bit addresses. This allows to access data pages 3...0 within segment 0 as
shown in the figure below. If the user does not want to use any data paging, no further
action is required.
MCA02265
255
1
15 0
IP Register
254
0
Code Segment
FF’FFFFH
FE’0000H
01’0000H
00’0000H
CSP Register
15 0
24/20/18-Bit Physical Code Address
C165H
Central Processor Unit
Data Sheet 74 2001-04-19
PRELIMINARY
- EXCERPT -
DPP0 (FE00H / 00H) SFR Reset Value: 0000H
DPP1 (FE02H / 01H) SFR Reset Value: 0001H
DPP2 (FE04H / 02H) SFR Reset Value: 0002H
DPP3 (FE06H / 03H) SFR Reset Value: 0003H
Data paging is performed by concatenating the lower 14 bits of an indirect or direct long
16-bit address with the contents of the DPP register selected by the upper two bits of the
16-bit address. The content of the selected DPP register specifies one of the 1024
possible data pages. This data page base address together with the 14-bit page offset
forms the physical 24-bit address (selectable part is driven to the address pins).
In case of non-segmented memory mode, only the two least significant bits of the
implicitly selected DPP register are used to generate the physical address. Thus,
extreme care should be taken when changing the content of a DPP register, if a non-
segmented memory model is selected, because otherwise unexpected results could
occur.
Bit Function
DPPxPN Data Page Number of DPPx
Specifies the data page selected via DPPx. Only the least significant two bits of
DPPx are significant, when segmentation is disabled.
- --
54321011 10 987615 14 13 12
-rw-- --
---
-
DPP0PN
- --
54321011 10 987615 14 13 12
-rw-- --
---
-
DPP1PN
- --
54321011 10 987615 14 13 12
-rw-- --
---
-
DPP2PN
- --
54321011 10 987615 14 13 12
-rw-- --
---
-
DPP3PN
C165H
Central Processor Unit
Data Sheet 75 2001-04-19
PRELIMINARY
- EXCERPT -
In case of the segmented memory mode the selected number of segment address bits
(via bitfield SALSEL) of the respective DPP register is output on the respective segment
address pins of Port 4 for all external data accesses.
A DPP register can be updated via any instruction, which is capable of modifying an
SFR.
Note: Due to the internal instruction pipeline, a new DPP value is not yet usable for the
operand address calculation of the instruction immediately following the
instruction updating the DPP register.
Figure 17 Addressing via the Data Page Pointers
Context Pointer CP
This non-bit addressable register is used to select the current register context. This
means that the CP register value determines the address of the first General Purpose
Register (GPR) within the current register bank of up to 16 wordwide and/or bytewide
GPRs.
MCA02264
1023
Data Pages
1022
1021
3
2
1
0
DPP Registers
DPP3-11
DPP2-10
DPP1-01
DPP0-00
15 14 0
16-Bit Data Address
14-Bit
Intra-Page Address
(concatenated with
content of DPPx).
Affer reset or with segmentation disabled the DPP registers select data pages 3...0.
All of the internal memory is accessible in these cases.
C165H
Central Processor Unit
Data Sheet 76 2001-04-19
PRELIMINARY
- EXCERPT -
CP (FE10H / 08H) SFR Reset Value: FC00H
Note: It is the user's responsibility that the physical GPR address specified via CP
register plus short GPR address must always be an internal RAM location. If this
condition is not met, unexpected results may occur.
• Do not set CP below the IRAM start address, ie. 00’FA00H/00’F600H/00’F200H
(1/2/3 KB)
• Do not set CP above 00’FDFEH
• Be careful using the upper GPRs with CP above 00’FDE0H
The CP register can be updated via any instruction which is capable of modifying an
SFR.
Note: Due to the internal instruction pipeline, a new CP value is not yet usable for GPR
address calculations of the instruction immediately following the instruction
updating the CP register.
The Switch Context instruction (SCXT) allows to save the content of register CP on the
stack and updating it with a new value in just one machine cycle.
Bit Function
cp Modifiable portion of register CP
Specifies the (word) base address of the current register bank.
When writing a value to register CP with bits CP.11...CP.9 = ‘000’, bits
CP.11...CP.10 are set to ‘11’ by hardware, in all other cases all bits of bit field
“cp” receive the written value.
1 01
54321011 10 987615 14 13 12
rrwr rr
11
r
cp
C165H
Central Processor Unit
Data Sheet 77 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 18 Register Bank Selection via Register CP
Several addressing modes use register CP implicitly for address calculations. The
addressing modes mentioned below are described in chapter “Instruction Set
Summary”.
Short 4-Bit GPR Addresses (mnemonic: Rw or Rb) specify an address relative to the
memory location specified by the contents of the CP register, ie. the base of the current
register bank.
Depending on whether a relative word (Rw) or byte (Rb) GPR address is specified, the
short 4-bit GPR address is either multiplied by two or not before it is added to the content
of register CP (see figure below). Thus, both byte and word GPR accesses are possible
in this way.
GPRs used as indirect address pointers are always accessed wordwise. For some
instructions only the first four GPRs can be used as indirect address pointers. These
GPRs are specified via short 2-bit GPR addresses. The respective physical address
calculation is identical to that for the short 4-bit GPR addresses.
MCD02003
R0
R1
R2
R3
R4
R5
R6
R7
R8
R9
R10
R11
R12
R13
R14
R15
Context
Pointer
(CP) + 30
(CP) + 28
(CP) + 2
(CP)
Internal RAM
.
.
.
C165H
Central Processor Unit
Data Sheet 78 2001-04-19
PRELIMINARY
- EXCERPT -
Short 8-Bit Register Addresses (mnemonic: reg or bitoff) within a range from F0H to
FFH interpret the four least significant bits as short 4-bit GPR address, while the four
most significant bits are ignored. The respective physical GPR address calculation is
identical to that for the short 4-bit GPR addresses. For single bit accesses on a GPR, the
GPR's word address is calculated as just described, but the position of the bit within the
word is specified by a separate additional 4-bit value.
Figure 19 Implicit CP Use by Short GPR Addressing Modes
Stack Pointer SP
This non-bit addressable register is used to point to the top of the internal system stack
(TOS). The SP register is pre-decremented whenever data is to be pushed onto the
stack, and it is post-incremented whenever data is to be popped from the stack. Thus,
the system stack grows from higher toward lower memory locations.
Since the least significant bit of register SP is tied to '0' and bits 15 through 12 are tied
to '1' by hardware, the SP register can only contain values from F000H to FFFEH. This
allows to access a physical stack within the internal RAM of the C165H. A virtual stack
(usually bigger) can be realized via software. This mechanism is supported by registers
STKOV and STKUN (see respective descriptions below).
The SP register can be updated via any instruction, which is capable of modifying an
SFR.
Note: Due to the internal instruction pipeline, a POP or RETURN instruction must not
immediately follow an instruction updating the SP register.
For word GPR
accesses
accesses
For byte GPR
Control
1111
Specified by reg or bitoff
Context
Pointer
+
4-Bit GPR
Address
2
*
MCD02005
Internal
GPRs
RAM
Must be
within the
RAM area
internal
C165H
Central Processor Unit
Data Sheet 79 2001-04-19
PRELIMINARY
- EXCERPT -
SP (FE12H / 09H) SFR Reset Value: FC00H
Stack Overflow Pointer STKOV
This non-bit addressable register is compared against the SP register after each
operation, which pushes data onto the system stack (eg. PUSH and CALL instructions
or interrupts) and after each subtraction from the SP register. If the content of the SP
register is less than the content of the STKOV register, a stack overflow hardware trap
will occur.
Since the least significant bit of register STKOV is tied to '0' and bits 15 through 12 are
tied to '1' by hardware, the STKOV register can only contain values from F000H to
FFFEH.
STKOV (FE14H / 0AH) SFR Reset Value: FA00H
The Stack Overflow Trap (entered when (SP) < (STKOV)) may be used in two different
ways:
• Fatal error indication treats the stack overflow as a system error through the
associated trap service routine. Under these circumstances data in the bottom of the
stack may have been overwritten by the status information stacked upon servicing the
stack overflow trap.
Bit Function
sp Modifiable portion of register SP
Specifies the top of the internal system stack.
Bit Function
stkov Modifiable portion of register STKOV
Specifies the lower limit of the internal system stack.
1 01
54321011 10 987615 14 13 12
rrwr rr
11
r
sp
1 01
54321011 10 987615 14 13 12
rrwr rr
11
r
stkov
C165H
Central Processor Unit
Data Sheet 80 2001-04-19
PRELIMINARY
- EXCERPT -
• Automatic system stack flushing allows to use the system stack as a 'Stack Cache'
for a bigger external user stack. In this case register STKOV should be initialized to a
value, which represents the desired lowest Top of Stack address plus 12 according to
the selected maximum stack size. This considers the worst case that will occur, when a
stack overflow condition is detected just during entry into an interrupt service routine.
Then, six additional stack word locations are required to push IP, PSW, and CSP for both
the interrupt service routine and the hardware trap service routine.
More details about the stack overflow trap service routine and virtual stack management
are given in chapter “System Programming”.
Stack Underflow Pointer STKUN
This non-bit addressable register is compared against the SP register after each
operation, which pops data from the system stack (eg. POP and RET instructions) and
after each addition to the SP register. If the content of the SP register is greater than the
the content of the STKUN register, a stack underflow hardware trap will occur.
Since the least significant bit of register STKUN is tied to '0' and bits 15 through 12 are
tied to '1' by hardware, the STKUN register can only contain values from F000H to
FFFEH.
STKUN (FE16H / 0BH) SFR Reset Value: FC00H
The Stack Underflow Trap (entered when (SP) > (STKUN)) may be used in two different
ways:
• Fatal error indication treats the stack underflow as a system error through the
associated trap service routine.
• Automatic system stack refilling allows to use the system stack as a 'Stack Cache'
for a bigger external user stack. In this case register STKUN should be initialized to a
value, which represents the desired highest Bottom of Stack address.
More details about the stack underflow trap service routine and virtual stack
management are given in chapter “System Programming”.
Bit Function
stkun Modifiable portion of register STKUN
Specifies the upper limit of the internal system stack.
1 01
54321011 10 987615 14 13 12
rrwr rr
11
r
stkun
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Scope of Stack Limit Control
The stack limit control realized by the register pair STKOV and STKUN detects cases
where the stack pointer SP is moved outside the defined stack area either by ADD or
SUB instructions or by PUSH or POP operations (explicit or implicit, ie. CALL or RET
instructions).
This control mechanism is not triggered, ie. no stack trap is generated, when
• the stack pointer SP is directly updated via MOV instructions
• the limits of the stack area (STKOV, STKUN) are changed, so that SP is outside of the
new limits.
Multiply/Divide High Register MDH
This register is a part of the 32-bit multiply/divide register, which is implicitly used by the
CPU, when it performs a multiplication or a division. After a multiplication, this non-bit
addressable register represents the high order 16 bits of the 32-bit result. For long
divisions, the MDH register must be loaded with the high order 16 bits of the 32-bit
dividend before the division is started. After any division, register MDH represents the
16-bit remainder.
MDH (FE0CH / 06H) SFR Reset Value: 0000H
Whenever this register is updated via software, the Multiply/Divide Register In Use
(MDRIU) flag in the Multiply/Divide Control register (MDC) is set to '1'.
When a multiplication or division is interrupted before its completion and when a new
multiply or divide operation is to be performed within the interrupt service routine, register
MDH must be saved along with registers MDL and MDC to avoid erroneous results.
A detailed description of how to use the MDH register for programming multiply and
divide algorithms can be found in chapter “System Programming”.
Multiply/Divide Low Register MDL
This register is a part of the 32-bit multiply/divide register, which is implicitly used by the
CPU, when it performs a multiplication or a division. After a multiplication, this non-bit
addressable register represents the low order 16 bits of the 32-bit result. For long
divisions, the MDL register must be loaded with the low order 16 bits of the 32-bit
Bit Function
mdh Specifies the high order 16 bits of the 32-bit multiply and divide register MD.
54321011 10 987615 14 13 12
rw
mdh
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dividend before the division is started. After any division, register MDL represents the 16-
bit quotient.
MDL (FE0EH / 07H) SFR Reset Value: 0000H
Whenever this register is updated via software, the Multiply/Divide Register In Use
(MDRIU) flag in the Multiply/Divide Control register (MDC) is set to '1'. The MDRIU flag
is cleared, whenever the MDL register is read via software.
When a multiplication or division is interrupted before its completion and when a new
multiply or divide operation is to be performed within the interrupt service routine, register
MDL must be saved along with registers MDH and MDC to avoid erroneous results.
A detailed description of how to use the MDL register for programming multiply and
divide algorithms can be found in chapter “System Programming”.
Multiply/Divide Control Register MDC
This bit addressable 16-bit register is implicitly used by the CPU, when it performs a
multiplication or a division. It is used to store the required control information for the
corresponding multiply or divide operation. Register MDC is updated by hardware during
each single cycle of a multiply or divide instruction.
MDC (FF0EH / 87H) SFR Reset Value: 0000H
When a division or multiplication was interrupted before its completion and the multiply/
divide unit is required, the MDC register must first be saved along with registers MDH
and MDL (to be able to restart the interrupted operation later), and then it must be
cleared prepare it for the new calculation. After completion of the new division or
multiplication, the state of the interrupted multiply or divide operation must be restored.
The MDRIU flag is the only portion of the MDC register which might be of interest for the
user. The remaining portions of the MDC register are reserved for dedicated use by the
Bit Function
mdl Specifies the low order 16 bits of the 32-bit multiply and divide register MD.
54321011 10 987615 14 13 12
rw
mdl
-!!--
54321011 10 987615 14 13 12
-r(w)-- --
---
-
!!!!!!!!!!!!- -
- - r(w) r(w) r(w) r(w) r(w) r(w) r(w)
MDR
IU
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hardware, and should never be modified by the user in another way than described
above. Otherwise, a correct continuation of an interrupted multiply or divide operation
cannot be guaranteed.
A detailed description of how to use the MDC register for programming multiply and
divide algorithms can be found in chapter “System Programming”.
Constant Zeros Register ZEROS
All bits of this bit-addressable register are fixed to '0' by hardware. This register can be
read only. Register ZEROS can be used as a register-addressable constant of all zeros,
ie. for bit manipulation or mask generation. It can be accessed via any instruction, which
is capable of addressing an SFR.
ZEROS (FF1CH / 8EH) SFR Reset Value: 0000H
Constant Ones Register ONES
All bits of this bit-addressable register are fixed to '1' by hardware. This register can be
read only. Register ONES can be used as a register-addressable constant of all ones,
ie. for bit manipulation or mask generation. It can be accessed via any instruction, which
is capable of addressing an SFR.
Bit Function
MDRIU Multiply/Divide Register In Use
‘0’: Cleared, when register MDL is read via software.
‘1’: Set when register MDL or MDH is written via software, or when a multiply
or divide instruction is executed.
!! Internal Machine Status
The multiply/divide unit uses these bits to control internal operations.
Never modify these bits without saving and restoring register MDC.
0 0 000
54321011 10 987615 14 13 12
r rrr rr
000
r
0000000 0
rrrrr rrrr
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ONES (FF1EH / 8FH) SFR Reset Value: FFFFH
5.5 PEC - Extension of Functionality
Introduction
Compared to existing C16x architecture, the PEC transfer function is enhanced by
extended functionality. The extended PEC function is a further step into DMA control
functionality. It especially supports integrated system design with XBUS as system bus.
Note: The device address decoding structure is always based on 24-bit addresses. But
due to the limited number of port P4 pins, only the address bits A22:A16 can be
made visible on the external X-Bus interface.
The extended PEC functions are defined as follows:
–Source pointer and destination pointer are extended to 24-bit pointer, thus enabling
PEC controlled data transfer between any two locations within the total address
space. Both 8-bit segment numbers of every source/destination pointer pair are
defined in one 16-bit SFR register; thus, 8 PEC segment number registers are
available for the 8 PEC channels.
–Two of the PEC channels are expanded by additional 16-bit transfer count registers;
when enabled, the original 8-bit bytecount in the control register serves as package
length count, thus defining the amount of bytes or words to be transferred with one
request. In C165H the package size is always limited to one transfer.
–For always two channels a chaining feature is provided. When enabled in the PEC
control register, a termination interrupt of one channel will automatically switch
transfer control to the other channel of the channel pair.
24-bit Extension of Source and Destination Pointers
The source and destination pointers specify the locations between which the data is to
be moved. For each of the eight PEC channels the source and destination pointers are
specified by one SFR register and two IRAM memory locations. One SFR register stores
the 8-bit segment number of the source (PECSSN) and the 8-bit segment number of the
destination (PECDSN) location in a respective 16-bit PEC Segment Number register
(PECSNx). The respective segment offset of source and destination are stored in IRAM
memory location identical to the IRAM locations of SRCPx and DSTPx pointers of Full-
Custom C16x standard PEC channels - thus the extension is fully compatible. With the
segment number extension of source and destination, data can be transferred by a PEC
transfer between any two locations within the 8 MByte address space of the C165H.
1 1 111
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r rrr rr
111
r
1111111 1
rrrrr rrrr
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Note: The segment number extension of source and destination is provided for all 8 PEC
channels. After reset, all 8 segment number registers PECSNx are cleared,
providing full compatibility to FC-C16x PEC channels.
The PEC segment number registers PECSNx are defined as follows:
PECSNx (Addresses see table) SFR Reset Value: 0000H
Bit Function
PECSSN PEC Source Segment Number
8-bit Segment Number used for addressing the source of the respective PEC
transfer.
Note: Bits 6:0 can be used externally (address bits A22:A16). Due to the limited
number of pins, the upper bit 7 can not be used externally but can still be
used for chip select (CS) generation.
PECDSN PEC Destination Segment Number
8-bit Segment Number used for addressing the destination of the respective
PEC transfer.
Note: Bits 14:8 can be used externally (address bits A22:A16). Due to the limited
number of pins, the upper bit 15 can not be used externally but can still be
used for chip select (CS) generation.
Table 12 PEC Segment Number Register Addresses
Register Address Reg. Space Register Address Reg. Space
PECSN0 FED0H / 68HSFR PECSN4 FED8H / 6CHSFR
PECSN1 FED2H / 69HSFR PECSN5 FEDAH / 6DHSFR
PECSN2 FED4H / 6AHSFR PECSN6 FEDCH / 6EHSFR
PECSN3 FED6H / 6BHSFR PECSN7 FEDEH / 6FHSFR
54321011 10 987615 14 13 12
rw
PECSSN
rw
PECDSN
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Extended PEC Channel Control
The PEC control registers with the extended functionality and their application for new
PEC control are defined as follows:
PECCx (Addresses: see table) SFR Reset Value: 0000H
Bit Function
COUNT PEC Transfer Count
Counts PEC transfers (bytes or words) and influences the channel’s action
BWT Byte / Word Transfer Selection
0: Transfer a Word
1: Transfer a Byte
INC Increment Control (Modification of SRCPx or DSTPx)
0 0: Pointers are not modified
0 1: Increment DSTPx by 1 or 2 (BWT)
1 0: Increment SRCPx by 1 or 2 (BWT)
1 1: Reserved. Do not use this combination. (changed to 10 by hardware)
CL Channel Link Control
0: PEC channels work independent
1: Pairs of channels are linked together
CLT Channel Link Toggle State
0: Even numbered PEC channel of linked channels active
1: Odd numbered PEC channel of linked channels active
PT Package Transfer
0: Single Transfer; extended Count2 not enabled
1: Package Transfer; extended Count2 enabled (only for channels 0 and 2)
Note: Package Transfer is only supported in PECC0 and PECC2
BWT-PT
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rwrwrw
CL
rwrwrw-rw
CLT-INC COUNT
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PEC Control Register Addresses
Byte/Word Transfer bit BWT controls, if a byte or a word is moved during a PEC service
cycle. This selection controls the transferred data size and the increment step for the
modified pointer.
Increment Control Field INC controls, if one of the PEC pointers is incremented after
the PEC transfer. It is not possible to increment both pointers, however. If the pointers
are not modified (INC=’00’), the respective channel will always move data from the same
source to the same destination.
Note: The reserved combination ‘11’ is changed to ‘10’ by hardware. However, it is not
recommended to use this combination.
The PEC Transfer Count Field COUNT controls the action of a respective PEC channel,
where the content of bit field COUNT at the time the request is activated selects the
action. COUNT may allow a specified number of PEC transfers, unlimited transfers or no
PEC service at all.
The table below summarizes, how the COUNT field itself, the interrupt requests flag IR
and the PEC channel action depends on the previous content of COUNT.
The PEC transfer counter allows to service a specified number of requests by the
respective PEC channel, and then (when COUNT reaches 00H) activate the interrupt
service routine, which is associated with the priority level. After each PEC transfer the
COUNT field is decremented and the request flag is cleared to indicate that the request
has been serviced.
Register Address Reg. Space Register Address Reg. Space
PECC0 FEC0H / 60HSFR PECC4 FEC8H / 64HSFR
PECC1 FEC2H / 61HSFR PECC5 FECAH / 65HSFR
PECC2 FEC4H / 62HSFR PECC6 FECCH / 66HSFR
PECC3 FEC6H / 63HSFR PECC7 FECEH / 67HSFR
Previous
COUNT
Modified
COUNT
IR after PEC
service
Action of PEC Channel
and Comments
FFH FFH ‘0’Move a Byte / Word
Continuous transfer mode, ie. COUNT is not modified
FEH..02H FDH..01H ‘0’Move a Byte / Word and decrement COUNT
01H 00H ‘1’Move a Byte / Word
Leave request flag set, which triggers another request
00H 00H (‘1’)No action!
Activate interrupt service routine rather than PEC channel.
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Continuous transfers are selected by the value FFH in bit field COUNT. In this case
COUNT is not modified and the respective PEC channel services any request until it is
disabled again.
When COUNT is decremented from 01H to 00H after a transfer, the request flag is not
cleared, which generates another request from the same source. When COUNT already
contains the value 00H, the respective PEC channel remains idle and the associated
interrupt service routine is activated instead. This allows to choose, if a level 15 or 14
request is to be serviced by the PEC or by the interrupt service routine.
Note: PEC transfers are only executed, if their priority level is higher than the CPU level,
ie. only PEC channels 7...4 are processed, while the CPU executes on level 14.
All interrupt request sources that are enabled and programmed for PEC service
should use different channels. Otherwise only one transfer will be performed for
all simultaneous requests. When COUNT is decremented to 00H, and the CPU is
to be interrupted, an incorrect interrupt vector will be generated.
Channel Link control bit CL controls the channel link mode. In this mode PEC
channels work by pair (channels 0 and 1, 2 and 3, 4 and 5, 6 and 7). The channel link
mode is enabled for one pair when the CL bit is set in any of the 2 PECCx registers. In
this case, the 2 channels handle PEC requests alternative to each other. The whole data
transfer is divided into several block transfers where each block is controlled by a PEC
channel. When a block transfer is completed, a channel link interrupt is generated and
the request processing is switched to the other PEC channel of the pair. This mechanism
allows to set up shadow and multiple buffers for PEC transfers by changing pointers and
count values of one channel when the other channel is active.
The very first transfer is always initiated with the even channel (called channel A, that is
channel 0, 2, 4 or 6). When the associated count field reaches 0 (COUNT or COUNT2
depending on the selected mode), the request service is transfered to the odd channel
(channel B, that is channel 1, 3, 5 or 7). If the CL bit of the "linked" channel is set and the
count field is different from 0, the next PEC requests will be serviced by this channel.
The channel link interrupts share one common interrupt node (Trap number 4CH - vector
location 00’0130H). This node is controlled by the Channel Link Interrupt Sub-Node
Control (CLISNC) register. It raises an interrupt request in case of one or more channel
link request flag and the respective enable control bit is set in CLISNC register. These
flags signal a PEC condition of the PEC linked channels which requires an action from
the CPU. The following conditions are possible:
1. in single transfer mode, a COUNT value change from 01H to 00H in a linked PEC
channel and the CL flag is set in the respective PEC control register,
2. in packet transfer mode, a COUNT2 value change from 0001H to 0000H in a linked
PEC channel and the CL flag is set in the respective PEC control register.
In these cases the CPU is requested to update the PEC control and pointer registers
while the next block transfer is executed. The last block transfer is determined by the
missing link bit in the linked PEC control register. If a service request hits a linked
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channel with a COUNT field equal to 00H and the channel link flag disabled, a standard
interrupt is performed as known from standard PEC channels.
CLISNC (FFA8H / D4H) SFR Reset Value: 0000H
Packet Transfer control bit PT is implemented only in PECC0 and PECC2. When set
to ’1’, this bit enables the Packet Transfer mode. In this mode, each service request
initiates the transfer of an entire data packet of a fixed size. The COUNT field in the
PECCx register is used to define the size of the packet (in number of bytes or words
depending on the value of BWT). Therefore packets up to 256 bytes/words may be
transfered.
The register PECXC0/2 is then used to specify the number of requests to be serviced by
a PEC packet transfer before activating the interrupt service routine, which is associated
with the priority level. After each PEC packet transfer, the COUNT2 field is decremented
and the request flag is cleared, and then when COUNT2 reaches 0000H, an interrupt
request is generated to the corresponding interrupt vector.
Note: In the C165H, the packet size is limited to 1. Packet transfers are not supported,
but the extended transfer count COUNT2 is used when PT bit is set.
Bit Function
xxIE Channel Link Interrupt Enable Bit (individual for each pair of linked channels)
’0’: Interrupt request disabled
’1’: Interrupt request enabled
xxIR Channel Service Request Flag
’0’: No channel link service request pending
’1’: The channel pair has raised a request to service a PEC channel after
channel link
-- ---
54321011 10 987615 14 13 12
- - rw rw- - rw rwrw-rw--
C6
IR C2
IE C0
IR
- --
rw-
C6
IE
rw
C2
IR C0
IE
C4
IR C4
IE
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PECXCx (FEFyH / 7zH, see table) SFR Reset Value: 0000H
PEC Extended Control Register Addresses
Source and destination pointers specifiy the locations between which the data is to be
moved. For PEC transfer description refer to Chapter 6.3, page 103, where the PEC
operation is descriped more in detail.
Channel Link Mode for Data Chaining
Data chaining with linked PEC channels is enabled, if the Channel Link Control Bit in
PECCx register is set to ’1’, either in one or both PEC channel control registers of a
channel pair. In this case, two PEC channels are linked together and handle chained
block transfers alternatively to each other. The whole data transfer is divided into several
block transfers where each block is controlled by one PEC channel of a channel pair.
When a data block is completely transferred a channel link interrupt is generated and
the PEC service request processing is automatically switched to the ’other’ PEC channel
of the channel-pair. Thus, PEC service requests addressed to a linked PEC channel are
either handled by linked PEC channel A or by linked PEC channel B. This channel toggle
allows to set up shadow and multiple buffers for PEC transfers by changing pointer and
count values of one channel while the other channel is active. The following table list the
channels that can be linked together and the channel numbers to address the linked
channels.
Bit Function
COUNT2 Extended PEC Transfer Count
Counts PEC transfers and influences the channel’s action in Packet transfer
mode
Register Address Reg. Space Register Address Reg. Space
PECXC0 FEF0H / 78HSFR PECXC2 FEF2H / 79HSFR
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COUNT2
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For each pair of linked channels, an internal channel flag, the Channel Link Toggle flag
CLT identifies which of the two PEC channels will serve the next PEC request. The CLT
flag is indicated in both PECCx registers of two linked PEC channels, where the CLT bit
in channel B always is inverse to the CLT bit in channel A. The very first transfer is
always started with the channel A if the CLT bit was not programmed otherwise before.
The CLT bit is only valid in case of linked PEC channels, indicated by the CL bits of linked
channels. If linking is not enabled, the CLT bit of both channels is always zero
(compatibility!).
The internal channel link flag CLT toggles, and the other channel begins service with the
next request if the "old" channel stops the service (COUNT=0 or COUNT2=0, dependent
on the mode), and if the new channel has in its PEC control register the CL flag enabled
and its transfer count is more than zero. Note: With the last transfer of a block transfer
(COUNT=0 or COUNT2=0), the channel link control flag CL of that channel is cleared in
its PECCx register. If the channel link flag CL of the new (chained) PEC control register
is found to be zero the whole data transfer is finished and the channel link interrupt is
coincidently a termination interrupt. The channel link mode is finished and the internal
channel toggle flag is cleared after the last transfer of the block, if the CL flags of both
pair channels are cleared.
Table 13 PEC Channels which could be linked together
Linked PEC Channels Linked PEC Channel
PEC Channel
A
PEC Channel
B
channel 0 channel 1 channel 0
channel 2 channel 3 channel 2
channel 4 channel 5 channel 4
channel 6 channel 7 channel 6
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6 Interrupt and Trap Functions
The architecture of the C165H supports several mechanisms for fast and flexible
response to service requests that can be generated from various sources internal or
external to the microcontroller. These mechanisms include:
Normal Interrupt Processing
The CPU temporarily suspends the current program execution and branches to an
interrupt service routine in order to service an interrupt requesting device. The current
program status (IP, PSW, in segmentation mode also CSP) is saved on the internal
system stack. A prioritization scheme with 16 priority levels allows the user to specify the
order in which multiple interrupt requests are to be handled.
Interrupt Processing via the Peripheral Event Controller (PEC)
A faster alternative to normal software controlled interrupt processing is servicing an
interrupt requesting device with the C165H's integrated Peripheral Event Controller
(PEC). Triggered by an interrupt request, the PEC performs a single word or byte data
transfer between any two locations in segment 0 (data pages 0 through 3) through one
of eight programmable PEC Service Channels. During a PEC transfer the normal
program execution of the CPU is halted for just 1 instruction cycle. No internal program
status information needs to be saved. The same prioritization scheme is used for PEC
service as for normal interrupt processing. PEC transfers share the 2 highest priority
levels.
Trap Functions
Trap functions are activated in response to special conditions that occur during the
execution of instructions. A trap can also be caused externally by the Non-Maskable
Interrupt pin NMI. Several hardware trap functions are provided for handling erroneous
conditions and exceptions that arise during the execution of an instruction. Hardware
traps always have highest priority and cause immediate system reaction. The software
trap function is invoked by the TRAP instruction, which generates a software interrupt for
a specified interrupt vector. For all types of traps the current program status is saved on
the system stack.
External Interrupt Processing
Although the C165H does not provide dedicated interrupt pins, it allows to connect
external interrupt sources and provides several mechanisms to react on external events,
including standard inputs, non-maskable interrupts and fast external interrupts. These
interrupt functions are alternate port functions, except for the non-maskable interrupt and
the reset input.
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6.1 Interrupt System Structure
The C165H provides up to 64 separate interrupt nodes that may be assigned to 16
priority levels. The 4 lowest nodes are reserved for the CPU - thus, up to 60 nodes are
available for all interrupts. In order to support modular and consistent software design
techniques, each source of an interrupt or PEC request is supplied with a separate
interrupt control register and interrupt vector. The control register contains the interrupt
request flag, the interrupt enable bit, and the interrupt priority of the associated source.
Each source request is activated by one specific event, depending on the selected
operating mode of the respective device. The only exceptions are the two serial channels
of the table, where an error interrupt request can be generated by different kinds of error,
and the two subnode interrupts controlled by the ISNC and CLISNC registers (see
Interrupt and PEC descriptions). However, specific status flags which identify the type of
error are implemented in the serial channels’ control registers.
The C165H provides a vectored interrupt system. In this system specific vector locations
in the memory space are reserved for the reset, trap, and interrupt service functions.
Whenever a request occurs, the CPU branches to the location that is associated with the
respective interrupt source. This allows direct identification of the source that caused the
request. The only exceptions are the class B hardware traps, which all share the same
interrupt vector. The status flags in the Trap Flag Register (TFR) can then be used to
determine which exception caused the trap. For the special software TRAP instruction,
the vector address is specified by the operand field of the instruction, which is a seven
bit trap number.
The reserved vector locations build a jump table in the low end of the C165H’s address
space (segment 0). The jump table is made up of the appropriate jump instructions that
transfer control to the interrupt or trap service routines, which may be located anywhere
within the address space. The entries of the jump table are located at the lowest
addresses in code segment 0 of the address space. Each entry occupies 2 words,
except for the reset vector and the hardware trap vectors, which occupy 4 or 8 words.
The table below lists all sources that are capable of requesting interrupt or PEC service
in the C165H, the associated interrupt vectors, their locations, their trap numbers and the
SFR addresses of associated interrupt control registers. It also lists the mnemonics of
the corresponding Interrupt Enable flags. The mnemonics are composed of a part that
specifies the respective source, followed by a part that specifies their function
(IE=Interrupt Enable flag). The same composition is used for the mnemonics of
according interrupt request flags (IR=Interrupt Request flag; example: CC0IR belongs to
interrupt source CC0INT) and for the names of according interrupt control registers
(IC=Interrupt Control; example: CC0IC) which are not included in Table 14.
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Table 14 C165H Interrupts and PEC Service Requests
Nr. Source of
Interrupt or PEC
Service Request
Interrupt
Name
Enable
Flag
Vector
Location
Trap
Number
SFR
hex
Addr
irq(0) GPT Timer 2 T2INT T2IE 00’0088H22H / 34DFF60
irq(1) GPT Timer 3 T3INT T3IE 00’008CH23H / 35DFF62
irq(2) GPT Timer 4 T4INT T4IE 00’0090H24H / 36DFF64
irq(3) GPT Timer 5 T5INT T5IE 00’0094H25H / 37DFF66
irq(4) GPT Timer 6 T6INT T6IE 00’0098H26H / 38DFF68
irq(5) GPT CAPREL
Register
CRINT CRIE 00’009CH27H / 39DFF6A
irq(6) ASC Transmit S0TINT S0TIE 00’00A8H2AH / 42DFF6C
irq(7) ASC Receive S0RINT S0RIE 00’00ACH2BH / 43DFF6E
irq(8) ASC Error S0EINT S0EIE 00’00B0H2CH / 44DFF70
irq(9) ASC Transmit
Buffer
S0TBINT S0TBIE 00’011CH47H / 71DF19C
irq(10) SSC Transmit SSCTINT SSCTIE 00’00B4H2DH / 45DFF72
irq(11) SSC Receive SSCRINT SSCRIE 00’00B8H2EH / 46DFF74
irq(12) SSC Error SSCEINT SSCEIE 00’00BCH2FH / 47DFF76
irq(13) ASC Autobaud
Start
ABSTINT ABSTIE 00’0118H46H / 70DF194
irq(14) ASC Autobaud End ABENDINT ABENDIE 00’0114H45H / 69DF18C
irq(15) rRTC Interrupt RTC_INT RTCIE 00’0110H44H / 68DF184
irq(16) UDC SETUP USETINT USETIE 00’00F0H3CH / 60DF178
irq(17) UDC Load Config
Done
ULCDINT ULCDIE 00’00ECH3BH / 59DF176
irq(18) UDC Suspend USSINT USSIE 00’00E8H3AH / 58DF174
irq(19) UDC Suspend off USSOINT USSOIE 00’00E4H39H / 57DF172
irq(20) UDC Start of Frame USOFINT USOFIE 00’00E0H38H / 56DF170
irq(21) UDC Config Val UCFGVINT UCFGVIE 00’00DCH37H / 55DF16E
irq(22) UDC TXWR UTXRINT UTXRIE 00’00D8H36H / 54DF16C
irq(23) UDC RXRR URXRINT URXRIE 00’00D4H35H / 53DF16A
irq(24) UDC TX Done7 UTD7INT UTD7IE 00’00D0H34H / 52DF168
irq(25) UDC TX Done6 UTD6INT UTD6IE 00’00CCH33H / 51DF166
C165H
Interrupt and Trap Functions
Data Sheet 95 2001-04-19
PRELIMINARY
- EXCERPT -
irq(26) UDC TX Done5 UTD5INT UTD5IE 00’00C8H32H / 50DF164
irq(27) UDC TX Done4 UTD4INT UTD4IE 00’00C4H31H / 49DF162
irq(28) UDC TX Done3 UTD3INT UTD3IE 00’00C0H30H / 48DF160
irq(29) UDC TX Done2 UTD2INT UTD2IE 00’005CH17H / 23DFF86
irq(30) UDC TX Done1 UTD1INT UTD1IE 00’0058H16H / 22DFF84
irq(31) UDC TX Done0 UTD0INT UTD0IE 00’0054H15H / 21DFF82
irq(32) UDC RX Done7 URD7INT URD7IE 00’0050H14H / 20DFF80
irq(33) UDC RX Done6 URD6INT URD6IE 00’004CH13H / 19DFF7E
irq(34) UDC RX Done5 URD5INT URD5IE 00’0048H12H / 18DFF7C
irq(35) UDC RX Done4 URD4INT URD4IE 00’0044H11H / 17DFF7A
irq(36) UDC RX Done3 URD3INT URD3IE 00’0040H10H / 16DFF78
irq(37) UDC RX Done2 URD2INT URD2IE 00’0080H20H / 32DFF9C
irq(38) UDC RX Done1 URD1INT URD1IE 00’0084H21H / 33DFF9E
irq(39) UDC RX Done0 URD0INT URD0IE 00’00F4H3DH / 61DF17A
irq(40) reserved 00’00F8H3EH / 62DF17C
irq(41) reserved 00’00A0H28H / 40DFF98
irq(42) IOM-2 I/O IOMIOINT IOMIOIE 00’00A4H29H / 41DFF9A
irq(43) IOM-2 Channel0 TX IOMC0TINT IOMC0TIE 00’00FCH3FH / 63DF17E
irq(44) IOM-2 Channel0
RX
IOMC0RINT IOMC0RIE 00’0120H48H / 72DF182
irq(45) IOM-2 Channel1 TX IOMC1TINT IOMC1TIE 00’0124H49H / 73DF18A
irq(46) IOM-2 Channel1
RX
IOMC1RINT IOMC1RIE 00’0128H4AH / 74DF192
irq(47) reserved 00’012CH4BH / 75DF19A
firq(0) Fast ext. Interrupt EX0INT EX0IE 00’0060H18H / 24DFF88
firq(1) Fast ext. Interrupt EX1INT EX1IE 00’0064H19H / 25DFF8A
firq(2) Fast ext. Interrupt EX2INT EX2IE 00’0068H1AH / 26DFF8C
firq(3) Fast ext. Interrupt EX3INT EX3IE 00’006CH1BH / 27DFF8E
firq(4) Fast ext. Interrupt EX4INT EX4IE 00’0070H1CH / 28DFF90
firq(5) Fast ext. Interrupt EX5INT EX5IE 00’0074H1DH / 29DFF92
Nr. Source of
Interrupt or PEC
Service Request
Interrupt
Name
Enable
Flag
Vector
Location
Trap
Number
SFR
hex
Addr
C165H
Interrupt and Trap Functions
Data Sheet 96 2001-04-19
PRELIMINARY
- EXCERPT -
Note:
1. The X-Bus interrupt xb(2), known from C16x device’s, is connected to the main
interrupt node of the X-Bus peripheral: IOMIOINT (xb(2) and irq(42)).
2. Each entry of the interrupt vector table provides space for two word instructions or one
doubleword instruction. The respective vector location results from multiplying the trap
number by 4 (4 bytes per entry).
3. One interrupt control register is provided for each interrupt node. All IC registers of the
C165H can be found in the SFR list.
Table 15 lists the vector locations for hardware traps and the corresponding status flags
in register TFR. It also lists the priorities of trap service for cases, where more than one
trap condition might be detected within the same instruction. After any reset (hardware
reset, software reset instruction SRST, or reset by watchdog timer overflow) program
execution starts at the reset vector at location 00’0000H. Reset conditions have priority
over every other system activity and therefore have the highest priority (trap priority III).
Software traps may be initiated to any vector location between 00’0000H and 00’01FCH.
A service routine entered via a software TRAP instruction is always executed on the
current CPU priority level which is indicated in bit field ILVL in register PSW. This means
that routines entered via the software TRAP instruction can be interrupted by all
hardware traps or higher level interrupt requests.
firq(6) Fast ext. Interrupt EX6INT EX6IE 00’0078H1EH / 30DFF94
firq(7) Fast ext. Interrupt EX7INT EX7IE 00’007CH1FH / 31DFF96
xb(0) UDC TXWR UTXRINT UTXRIE 00’0100H40H / 64DF186
xb(1) reserved 00’0104H41H / 65DF18E
xb(2) IOM-2 IO IOMIOINT IOMIOIE 00’0108H42H / 66DF196
xb(3) Internal PLL Lock /
RTC
XP3INT XP3IE 00’010CH43H / 67DF19E
CLISN Interrupt CLISNINT CLISNIE 00’0130H4CH / 76DFFA8
Nr. Source of
Interrupt or PEC
Service Request
Interrupt
Name
Enable
Flag
Vector
Location
Trap
Number
SFR
hex
Addr
C165H
Interrupt and Trap Functions
Data Sheet 97 2001-04-19
PRELIMINARY
- EXCERPT -
Table 15 Hardware Traps and Vector Locations
Normal Interrupt Processing and PEC Service
During each instruction cycle one out of all sources which require PEC or interrupt
processing is selected according to its interrupt priority. This priority of interrupts and
PEC requests is programmable in two levels. Each requesting source can be assigned
to a specific priority. A second level (called “group priority”) allows to specify an internal
order for simultaneous requests from a group of different sources on the same priority
level. At the end of each instruction cycle the one source request with the highest current
priority will be determined by the interrupt system. This request will then be serviced, if
its priority is higher than the current CPU priority in register PSW.
Exception Condition Trap
Flag
Trap
Vector
Vector
Location
Trap
Number
Trap
Priority
Reset Functions:
Hardware Reset
Software Reset
Watchdog Timer
Overflow
RESET
RESET
RESET
00’0000H
00’0000H
00’0000H
00H
00H
00H
III
III
III
Class A Hardware Traps:
Non-Maskable Interrupt
Stack Overflow
Stack Underflow
Debug Trap
NMI
STKOF
STKUF
DEBUG
NMITRAP
STOTRAP
STUTRAP
DEBTRAP
00’0008H
00’0010H
00’0018H
00’0020H
02H
04H
06H
08H
II
II
II
II
Class B Hardware Traps:
Undefined Opcode
Protected Instruction
Fault
Illegal Word Operand
Access
Illegal Instruction Access
Illegal External Bus
Access
UNDOPC
PRTFLT
#
ILLOPA
ILLINA
ILLBUS
BTRAP
BTRAP
BTRAP
BTRAP
BTRAP
00’0028H
00’0028H
00’0028H
00’0028H
00’0028H
0AH
0AH
0AH
0AH
0AH
I
I
I
I
I
Reserved [2CH – 3CH][0B
H –
0FH]
Software Traps
TRAP Instruction
Any
[00’0000H –
00’01FCH]
in steps
of 4H
Any
[00H –
7FH]
Current
CPU
Priority
C165H
Interrupt and Trap Functions
Data Sheet 98 2001-04-19
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- EXCERPT -
Interrupt System Register Description
Interrupt processing is controlled globally by register PSW through a general interrupt
enable bit (IEN) and the CPU priority field (ILVL). Additionally the different interrupt
sources are controlled individually by their specific interrupt control registers (...IC).
Thus, the acceptance of requests by the CPU is determined by both the individual
interrupt control registers and the PSW. PEC services are controlled by the respective
PECCx register and the source and destination pointers, which specify the task of the
respective PEC service channel.
6.2 Interrupt Control Registers
All interrupt control registers are organized identically. The lower 8 bits of an interrupt
control register contain the complete interrupt status information of the associated
source, which is required during one round of prioritization, the upper 8 bits of the
respective register are reserved. All interrupt control registers are bit-addressable and all
bits can be read or written via software. This allows each interrupt source to be
programmed or modified with just one instruction. When accessing interrupt control
registers through instructions which operate on word data types, their upper 8 bits
(15...8) will return zeros, when read, and will discard written data.
The layout of the Interrupt Control registers shown below applies to each xxIC register,
where xx stands for the mnemonic for the respective source.
C165H
Interrupt and Trap Functions
Data Sheet 99 2001-04-19
PRELIMINARY
- EXCERPT -
xxIC (yyyyH / zzH) <SFR area> Reset Value: - - 00H
The Interrupt Request Flag is set by hardware whenever a service request from the
respective source occurs. It is cleared automatically upon entry into the interrupt service
routine or upon a PEC service. In the case of PEC service the Interrupt Request flag
remains set, if the COUNT field in register PECCx of the selected PEC channel
decrements to zero. This allows a normal CPU interrupt to respond to a completed PEC
block transfer.
Note: Modifying the Interrupt Request flag via software causes the same effects as if it
had been set or cleared by hardware.
Interrupt Priority Level and Group Level
The four bits of bit field ILVL specify the priority level of a service request for the
arbitration of simultaneous requests. The priority increases with the numerical value of
ILVL, so 0000B is the lowest and 1111B is the highest priority level.
When more than one interrupt request on a specific level gets active at the same time,
the values in the respective bit fields GLVL are used for second level arbitration to select
one request for being serviced. Again the group priority increases with the numerical
value of GLVL, so 00B is the lowest and 11B is the highest group priority.
Bit Function
GLVL Group Level
Defines the internal order for simultaneous requests of the same priority.
3: Highest group priority
0: Lowest group priority
ILVL Interrupt Priority Level
Defines the priority level for the arbitration of requests.
FH: Highest priority level
0H: Lowest priority level
xxIE Interrupt Enable Control Bit (individually enables/disables a specific
source)
‘0’: Interrupt request is disabled
‘1’: Interrupt Request is enabled
xxIR Interrupt Request Flag
‘0’: No request pending
‘1’: This source has raised an interrupt request
54321011 10 987615 14 13 12
rw rw----rw rw----
xxIExxIR GLVLILVL
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Interrupt and Trap Functions
Data Sheet 100 2001-04-19
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- EXCERPT -
Note: All interrupt request sources that are enabled and programmed to the same
priority level must always be programmed to different group priorities. Otherwise
an incorrect interrupt vector will be generated.
Upon entry into the interrupt service routine, the priority level of the source that won the
arbitration and who’s priority level is higher than the current CPU level, is copied into bit
field ILVL of register PSW after pushing the old PSW contents on the stack.
The interrupt system of the C165H allows nesting of up to 15 interrupt service routines
of different priority levels (level 0 cannot be arbitrated).
Interrupt requests that are programmed to priority levels 15 or 14 (ie, ILVL=111XB) will
be serviced by the PEC, unless the COUNT field of the associated PECC register
contains zero. In this case the request will instead be serviced by normal interrupt
processing. Interrupt requests that are programmed to priority levels 13 through 1 will
always be serviced by normal interrupt processing.
Note: Priority level 0000B is the default level of the CPU. Therefore a request on level 0
will never be serviced, because it can never interrupt the CPU. However, an
enabled interrupt request on level 0000B will terminate the C165H’s Idle mode and
reactivate the CPU.
For interrupt requests which are to be serviced by the PEC, the associated PEC channel
number is derived from the respective ILVL (LSB) and GLVL (see figure below). So
programming a source to priority level 15 (ILVL=1111B) selects the PEC channel group
7...4, programming a source to priority level 14 (ILVL=1110B) selects the PEC channel
group 3...0. The actual PEC channel number is then determined by the group priority
field GLVL.
Figure 20 Priority Levels and PEC Channels
Simultaneous requests for PEC channels are prioritized according to the PEC channel
number, where channel 0 has lowest and channel 7 has highest priority.
Note: All sources that request PEC service must be programmed to different PEC
channels. Otherwise an incorrect PEC channel may be activated.
MCD02006
ILVL GLVL
PEC Channel
Interrupt
Control Register
PEC Control
C165H
Interrupt and Trap Functions
Data Sheet 101 2001-04-19
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The table below shows in a few examples, which action is executed with a given
programming of an interrupt control register.
Table 16 Programming Example
Note: All requests on levels 13...1 cannot initiate PEC transfers. They are always
serviced by an interrupt service routine. No PECC register is associated and no
COUNT field is checked.
Interrupt Control Functions in the PSW
The Processor Status Word (PSW) is functionally divided into 2 parts: the lower byte of
the PSW basically represents the arithmetic status of the CPU, the upper byte of the
PSW controls the interrupt system of the C165H and the arbitration mechanism for the
external bus interface.
Note: Pipeline effects have to be considered when enabling/disabling interrupt requests
via modifications of register PSW (see chapter “The Central Processing Unit”).
Priority Level Type of Service
ILVL GLVL COUNT = 00H COUNT ≠ 00H
1 1 1 1 1 1 CPU interrupt,
level 15, group priority 3
PEC service,
channel 7
1 1 1 1 1 0 CPU interrupt,
level 15, group priority 2
PEC service,
channel 6
1 1 1 0 1 0 CPU interrupt,
level 14, group priority 2
PEC service,
channel 2
1 1 0 1 1 0 CPU interrupt,
level 13, group priority 2
CPU interrupt,
level 13, group priority 2
0 0 0 1 1 1 CPU interrupt,
level 1, group priority 3
CPU interrupt,
level 1, group priority 3
0 0 0 1 0 0 CPU interrupt,
level 1, group priority 0
CPU interrupt,
level 1, group priority 0
0 0 0 0 X X No service! No service!
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Interrupt and Trap Functions
Data Sheet 102 2001-04-19
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PSW (FF10H / 88H) SFR Reset Value: 0000H
CPU Priority ILVL defines the current level for the operation of the CPU. This bit field
reflects the priority level of the routine that is currently executed. Upon entry into an
interrupt service routine this bit field is updated with the priority level of the request that
is being serviced. The PSW is saved on the system stack before. The CPU level
determines the minimum interrupt priority level that will be serviced. Any request on the
same or a lower level will not be acknowledged.
The current CPU priority level may be adjusted via software to control which interrupt
request sources will be acknowledged.
PEC transfers do not really interrupt the CPU, but rather “steal” a single cycle, so PEC
services do not influence the ILVL field in the PSW.
Hardware traps switch the CPU level to maximum priority (ie. 15) so no interrupt or PEC
requests will be acknowledged while an exception trap service routine is executed.
Note: The TRAP instruction does not change the CPU level, so software invoked trap
service routines may be interrupted by higher requests.
Interrupt Enable bit IEN globally enables or disables PEC operation and the
acceptance of interrupts by the CPU. When IEN is cleared, no interrupt requests are
accepted by the CPU. When IEN is set to '1', all interrupt sources, which have been
individually enabled by the interrupt enable bits in their associated control registers, are
globally enabled.
Note: Traps are non-maskable and are therefore not affected by the IEN bit.
Bit Function
N, C, V, Z, E,
MULIP, USR0
CPU status flags (Described in section “The Central Processing Unit”)
Define the current status of the CPU (ALU, multiplication unit).
HLDEN HOLD Enable (Enables External Bus Arbitration)
0: Bus arbitration disabled, P6.7...P6.5 may be used for general purpose I/O
1: Bus arbitration enabled, P6.7...P6.5 serve as BREQ, HLDA, HOLD, resp.
ILVL CPU Priority Level
Defines the current priority level for the CPU
FH: Highest priority level
0H: Lowest priority level
IEN Interrupt Enable Control Bit (globally enables/disables interrupt requests)
‘0’: Interrupt requests are disabled
‘1’: Interrupt requests are enabled
HLD
EN -MUL
IP
USR0 NZCVE
54321011 10 987615 14 13 12
rw rw rw rw-rw rw rw-rw -rw
IEN --
ILVL
rw
C165H
Interrupt and Trap Functions
Data Sheet 103 2001-04-19
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- EXCERPT -
6.3 Operation of the PEC Channels
The C165H's Peripheral Event Controller (PEC) provides 8 PEC service channels, which
move a single byte or word. This is the fastest possible interrupt response and in many
cases is sufficient to service the respective peripheral request (eg. serial channels, etc.).
Each channel is controlled by a dedicated PEC Channel Counter/Control register
(PECCx) and a pair of pointers for source (SRCPx) and destination (DSTPx) of the data
transfer.
The PECC registers control the action that is performed by the respective PEC channel.
Note: For the PECCx register description, please also refer to page 86 of Sub-
Chapter "Extended PEC Channel Control".
Byte/Word Transfer bit BWT controls, if a byte or a word is moved during a PEC service
cycle. This selection controls the transferred data size and the increment step for the
modified pointer.
Increment Control Field INC controls, if one of the PEC pointers is incremented after
the PEC transfer. It is not possible to increment both pointers, however. If the pointers
are not modified (INC=’00’), the respective channel will always move data from the same
source to the same destination.
Note: The reserved combination ‘11’ is changed to ‘10’ by hardware. However, it is not
recommended to use this combination.
The PEC Transfer Count Field COUNT controls the action of a respective PEC channel,
where the content of bit field COUNT at the time the request is activated selects the
action. COUNT may allow a specified number of PEC transfers, unlimited transfers or no
PEC service at all.
The table below summarizes, how the COUNT field itself, the interrupt requests flag IR
and the PEC channel action depends on the previous content of COUNT.
Previous
COUNT
Modified
COUNT
IR after PEC
service
Action of PEC Channel
and Comments
FFH FFH ‘0’Move a Byte / Word
Continuous transfer mode, ie. COUNT is not modified
FEH..02H FDH..01H ‘0’Move a Byte / Word and decrement COUNT
01H 00H ‘1’Move a Byte / Word
Leave request flag set, which triggers another request
00H 00H (‘1’)No action!
Activate interrupt service routine rather than PEC channel.
C165H
Interrupt and Trap Functions
Data Sheet 104 2001-04-19
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- EXCERPT -
The PEC transfer counter allows to service a specified number of requests by the
respective PEC channel, and then (when COUNT reaches 00H) activate the interrupt
service routine, which is associated with the priority level. After each PEC transfer the
COUNT field is decremented and the request flag is cleared to indicate that the request
has been serviced.
Continuous transfers are selected by the value FFH in bit field COUNT. In this case
COUNT is not modified and the respective PEC channel services any request until it is
disabled again.
When COUNT is decremented from 01H to 00H after a transfer, the request flag is not
cleared, which generates another request from the same source. When COUNT already
contains the value 00H, the respective PEC channel remains idle and the associated
interrupt service routine is activated instead. This allows to choose, if a level 15 or 14
request is to be serviced by the PEC or by the interrupt service routine.
Note: PEC transfers are only executed, if their priority level is higher than the CPU level,
ie. only PEC channels 7...4 are processed, while the CPU executes on level 14.
All interrupt request sources that are enabled and programmed for PEC service
should use different channels. Otherwise only one transfer will be performed for
all simultaneous requests. When COUNT is decremented to 00H, and the CPU is
to be interrupted, an incorrect interrupt vector will be generated.
The source and destination pointers specifiy the locations between which the data is
to be moved. A pair of pointers (SRCPx and DSTPx) is associated with each of the 8
PEC channels. These pointers do not reside in specific SFRs, but are mapped into the
internal RAM of the C165H just below the bit-addressable area (see figure below).
Figure 21 Mapping of PEC Pointers into the Internal RAM
DSTP7 00’FCFEH
SRCP7 00’FCFCH
DSTP6 00’FCFAH
SRCP6 00’FCF8H
DSTP5 00’FCF6H
SRCP5 00’FCF4H
DSTP4 00’FCF2H
SRCP4 00’FCF0H
DSTP3 00’FCEEH
SRCP3 00’FCECH
DSTP2 00’FCEAH
SRCP2 00’FCE8H
DSTP1 00’FCE6H
SRCP1 00’FCE4H
DSTP0 00’FCE2H
SRCP0 00’FCE0H
C165H
Interrupt and Trap Functions
Data Sheet 105 2001-04-19
PRELIMINARY
- EXCERPT -
PEC data transfers do not use the data page pointers DPP3...DPP0, see also
Chapter 5.5, "PEC - Extension of Functionality". The PEC source and destination
pointers are used as 16-bit intra-segment addresses within segment 0, so data can be
transferred between any two locations within the first four data pages 3...0.
The pointer locations for inactive PEC channels may be used for general data storage.
Only the required pointers occupy RAM locations.
Note: If word data transfer is selected for a specific PEC channel (ie. BWT=’0’), the
respective source and destination pointers must both contain a valid word address
which points to an even byte boundary. Otherwise the Illegal Word Access trap will
be invoked, when this channel is used.
6.4 Prioritization of Interrupt and PEC Service Requests
Interrupt and PEC service requests from all sources can be enabled, so they are
arbitrated and serviced (if they win), or they may be disabled, so their requests are
disregarded and not serviced.
Enabling and disabling interrupt requests may be done via three mechanisms:
Control Bits allow to switch each individual source “ON” or “OFF”, so it may generate a
request or not. The control bits (xxIE) are located in the respective interrupt control
registers. All interrupt requests may be enabled or disabled generally via bit IEN in
register PSW. This control bit is the “main switch” that selects, if requests from any
source are accepted or not.
For a specific request to be arbitrated the respective source’s enable bit and the global
enable bit must both be set.
The Priority Level automatically selects a certain group of interrupt requests that will be
acknowledged, disclosing all other requests. The priority level of the source that won the
arbitration is compared against the CPU’s current level and the source is only serviced,
if its level is higher than the current CPU level. Changing the CPU level to a specific value
via software blocks all requests on the same or a lower level. An interrupt source that is
assigned to level 0 will be disabled and never be serviced.
The ATOMIC and EXTend instructions automatically disable all interrupt requests for
the duration of the following 1...4 instructions. This is useful eg. for semaphore handling
and does not require to re-enable the interrupt system after the unseparable instruction
sequence (see chapter “System Programming”).
Interrupt Class Management
An interrupt class covers a set of interrupt sources with the same importance, ie. the
same priority from the system’s viewpoint. Interrupts of the same class must not interrupt
each other. The C165H supports this function with two features:
C165H
Interrupt and Trap Functions
Data Sheet 106 2001-04-19
PRELIMINARY
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Classes with up to 4 members can be established by using the same interrupt priority
(ILVL) and assigning a dedicated group level (GLVL) to each member. This functionality
is built-in and handled automatically by the interrupt controller.
Classes with more than 4 members can be established by using a number of adjacent
interrupt priorities (ILVL) and the respective group levels (4 per ILVL). Each interrupt
service routine within this class sets the CPU level to the highest interrupt priority within
the class. All requests from the same or any lower level are blocked now, ie. no request
of this class will be accepted.
The example below establishes 3 interrupt classes which cover 2 or 3 interrupt priorities,
depending on the number of members in a class. A level 6 interrupt disables all other
sources in class 2 by changing the current CPU level to 8, which is the highest priority
(ILVL) in class 2. Class 1 requests or PEC requests are still serviced in this case.
The 19 interrupt sources (excluding PEC requests) are so assigned to 3 classes of
priority rather than to 7 different levels, as the hardware support would do.
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Interrupt and Trap Functions
Data Sheet 107 2001-04-19
PRELIMINARY
- EXCERPT -
Table 17 Software controlled Interrupt Classes (Example)
ILVL
(Priority)
GLVL Interpretation
3210
15 PEC service on up to 8 channels
14
13
12 X X X X Interrupt Class 1
5 sources on 2 levels
11 X
10
9
8 X X X X Interrupt Class 2
9 sources on 3 levels
7XXXX
6X
5 X X X X Interrupt Class 3
5 sources on 2 levels
4X
3
2
1
0 No service!
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Interrupt and Trap Functions
Data Sheet 108 2001-04-19
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6.5 Saving the Status during Interrupt Service
Before an interrupt request that has been arbitrated is actually serviced, the status of the
current task is automatically saved on the system stack. The CPU status (PSW) is saved
along with the location, where the execution of the interrupted task is to be resumed after
returning from the service routine. This return location is specified through the Instruction
Pointer (IP) and, in case of a segmented memory model, the Code Segment Pointer
(CSP). Bit SGTDIS in register SYSCON controls, how the return location is stored.
The system stack receives the PSW first, followed by the IP (unsegmented) or followed
by CSP and then IP (segmented mode). This optimizes the usage of the system stack,
if segmentation is disabled.
The CPU priority field (ILVL in PSW) is updated with the priority of the interrupt request
that is to be serviced, so the CPU now executes on the new level. If a multiplication or
division was in progress at the time the interrupt request was acknowledged, bit MULIP
in register PSW is set to ‘1’. In this case the return location that is saved on the stack is
not the next instruction in the instruction flow, but rather the multiply or divide instruction
itself, as this instruction has been interrupted and will be completed after returning from
the service routine.
Figure 22 Task Status saved on the System Stack
(Unsegmented)
PSW
System Stack after
Interrupt EntryInterrupt Entry
System Stack beforea) b)
SP
High
Addresses
Low
Addresses
--
--
--
SP IP
--
MCD02226
c) Interrupt Entry
System Stack after
(Segmented)
Task
Interrupted
Status of
CSP
PSW
IP SP
C165H
Interrupt and Trap Functions
Data Sheet 109 2001-04-19
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- EXCERPT -
The interrupt request flag of the source that is being serviced is cleared. The IP is loaded
with the vector associated with the requesting source (the CSP is cleared in case of
segmentation) and the first instruction of the service routine is fetched from the
respective vector location, which is expected to branch to the service routine itself. The
data page pointers and the context pointer are not affected.
When the interrupt service routine is left (RETI is executed), the status information is
popped from the system stack in the reverse order, taking into account the value of bit
SGTDIS.
Context Switching
An interrupt service routine usually saves all the registers it uses on the stack, and
restores them before returning. The more registers a routine uses, the more time is
wasted with saving and restoring. The C165H allows to switch the complete bank of CPU
registers (GPRs) with a single instruction, so the service routine executes within its own,
separate context.
The instruction “SCXT CP, #New_Bank” pushes the content of the context pointer (CP)
on the system stack and loads CP with the immediate value “New_Bank”, which selects
a new register bank. The service routine may now use its “own registers”. This register
bank is preserved, when the service routine terminates, ie. its contents are available on
the next call.
Before returning (RETI) the previous CP is simply POPped from the system stack, which
returns the registers to the original bank.
Note: The first instruction following the SCXT instruction must not use a GPR.
Resources that are used by the interrupting program must eventually be saved and
restored, eg. the DPPs and the registers of the MUL/DIV unit.
6.6 Interrupt Response Times
The interrupt response time defines the time from an interrupt request flag of an enabled
interrupt source being set until the first instruction (I1) being fetched from the interrupt
vector location. The basic interrupt response time for the C165H is 3 instruction cycles.
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Figure 23 Pipeline Diagram for Interrupt Response Time
All instructions in the pipeline including instruction N (during which the interrupt request
flag is set) are completed before entering the service routine. The actual execution time
for these instructions (eg. waitstates) therefore influences the interrupt response time.
In the figure above the respective interrupt request flag is set in cycle 1 (fetching of
instruction N). The indicated source wins the prioritization round (during cycle 2). In cycle
3 a TRAP instruction is injected into the decode stage of the pipeline, replacing
instruction N+1 and clearing the source's interrupt request flag to '0'. Cycle 4 completes
the injected TRAP instruction (save PSW, IP and CSP, if segmented mode) and fetches
the first instruction (I1) from the respective vector location.
All instructions that entered the pipeline after setting of the interrupt request flag (N+1,
N+2) will be executed after returning from the interrupt service routine.
The minimum interrupt response time is 5 states (10 TCL). This requires program
execution from the internal code memory, no external operand read requests and setting
the interrupt request flag during the last state of an instruction cycle. When the interrupt
request flag is set during the first state of an instruction cycle, the minimum interrupt
response time under these conditions is 6 state times (12 TCL).
The interrupt response time is increased by all delays of the instructions in the pipeline
that are executed before entering the service routine (including N).
• When internal hold conditions between instruction pairs N-2/N-1 or N-1/N occur, or
instruction N explicitly writes to the PSW or the SP, the minimum interrupt response
time may be extended by 1 state time for each of these conditions.
• When instruction N reads an operand from the internal code memory, or when N is a
call, return, trap, or MOV Rn, [Rm+ #data16] instruction, the minimum interrupt
Pipeline Stage Cycle 1 Cycle 2 Cycle 3 Cycle 4
FETCH N N + 1N + 2I1
DECODE N - 1 N TRAP (1) TRAP (2)
EXECUTE N - 2 N - 1 N TRAP
WRITEBACK N - 3 N - 2 N - 1 N
Interrupt Response Time
1
0
IR-Flag
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response time may additionally be extended by 2 state times during internal code
memory program execution.
• In case instruction N reads the PSW and instruction N-1 has an effect on the condition
flags, the interrupt response time may additionally be extended by 2 state times.
The worst case interrupt response time during internal code memory program execution
adds to 12 state times (24 TCL).
Any reference to external locations increases the interrupt response time due to pipeline
related access priorities. The following conditions have to be considered:
• Instruction fetch from an external location
• Operand read from an external location
• Result write-back to an external location
Depending on where the instructions, source and destination operands are located,
there are a number of combinations. Note, however, that only access conflicts contribute
to the delay.
A few examples illustrate these delays:
• The worst case interrupt response time including external accesses will occur, when
instructions N, N+1 and N+2 are executed out of external memory, instructions N-1
and N require external operand read accesses, instructions N-3 through N write back
external operands, and the interrupt vector also points to an external location. In this
case the interrupt response time is the time to perform 9 word bus accesses, because
instruction I1 cannot be fetched via the external bus until all write, fetch and read
requests of preceding instructions in the pipeline are terminated.
• When the above example has the interrupt vector pointing into the internal code
memory, the interrupt response time is 7 word bus accesses plus 2 states, because
fetching of instruction I1 from internal code memory can start earlier.
• When instructions N, N+1 and N+2 are executed out of external memory and the
interrupt vector also points to an external location, but all operands for instructions N-
3 through N are in internal memory, then the interrupt response time is the time to
perform 3 word bus accesses.
• When the above example has the interrupt vector pointing into the internal code
memory, the interrupt response time is 1 word bus access plus 4 states.
After an interrupt service routine has been terminated by executing the RETI instruction,
and if further interrupts are pending, the next interrupt service routine will not be entered
until at least two instruction cycles have been executed of the program that was
interrupted. In most cases two instructions will be executed during this time. Only one
instruction will typically be executed, if the first instruction following the RETI instruction
is a branch instruction (without cache hit), or if it reads an operand from internal code
memory, or if it is executed out of the internal RAM.
Note: A bus access in this context includes all delays which can occur during an external
bus cycle.
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6.7 PEC Response Times
The PEC response time defines the time from an interrupt request flag of an enabled
interrupt source being set until the PEC data transfer being started. The basic PEC
response time for the C165H is 2 instruction cycles.
Figure 24 Pipeline Diagram for PEC Response Time
In Figure 24 the respective interrupt request flag is set in cycle 1 (fetching of instruction
N). The indicated source wins the prioritization round (during cycle 2). In cycle 3 a PEC
transfer “instruction” is injected into the decode stage of the pipeline, suspending
instruction N+1 and clearing the source's interrupt request flag to '0'. Cycle 4 completes
the injected PEC transfer and resumes the execution of instruction N+1.
All instructions that entered the pipeline after setting of the interrupt request flag (N+1,
N+2) will be executed after the PEC data transfer.
Note: When instruction N reads any of the PEC control registers PECC7...PECC0, while
a PEC request wins the current round of prioritization, this round is repeated and
the PEC data transfer is started one cycle later.
The minimum PEC response time is 3 states (6 TCL). This requires program execution
from the internal code memory, no external operand read requests and setting the
interrupt request flag during the last state of an instruction cycle. When the interrupt
request flag is set during the first state of an instruction cycle, the minimum PEC
response time under these conditions is 4 state times (8 TCL).
The PEC response time is increased by all delays of the instructions in the pipeline that
are executed before starting the data transfer (including N).
Pipeline Stage Cycle 1 Cycle 2 Cycle 3 Cycle 4
FETCHN N + 1N + 2N + 2
DECODE N - 1 N PEC N + 1
EXECUTE N - 2 N - 1 N PEC
WRITEBACK N - 3 N - 2 N - 1 N
PEC Response Time
1
0
IR-Flag
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• When internal hold conditions between instruction pairs N-2/N-1 or N-1/N occur, the
minimum PEC response time may be extended by 1 state time for each of these
conditions.
• When instruction N reads an operand from the internal code memory, or when N is a
call, return, trap, or MOV Rn, [Rm+ #data16] instruction, the minimum PEC response
time may additionally be extended by 2 state times during internal code memory
program execution.
• In case instruction N reads the PSW and instruction N-1 has an effect on the condition
flags, the PEC response time may additionally be extended by 2 state times.
• The worst case PEC response time during internal code memory program execution
adds to 9 state times (18 TCL).
Any reference to external locations increases the PEC response time due to pipeline
related access priorities. The following conditions have to be considered:
• Instruction fetch from an external location
• Operand read from an external location
• Result write-back to an external location
Depending on where the instructions, source and destination operands are located,
there are a number of combinations. Note, however, that only access conflicts contribute
to the delay.
A few examples illustrate these delays:
• The worst case interrupt response time including external accesses will occur, when
instructions N and N+1 are executed out of external memory, instructions N-1 and N
require external operand read accesses and instructions N-3, N-2 and N-1 write back
external operands. In this case the PEC response time is the time to perform 7 word
bus accesses.
• When instructions N and N+1 are executed out of external memory, but all operands
for instructions N-3 through N-1 are in internal memory, then the PEC response time
is the time to perform 1 word bus access plus 2 state times.
Once a request for PEC service has been acknowledged by the CPU, the execution of
the next instruction is delayed by 2 state times plus the additional time it might take to
fetch the source operand from internal code memory or external memory and to write the
destination operand over the external bus in an external program environment.
Note: A bus access in this context includes all delays which can occur during an external
bus cycle.
6.8 External Interrupts
Although the C165H has no dedicated INTR input pins, it provides many possibilities to
react on external asynchronous events by using a number of I/O lines for interrupt input.
The interrupt function may either be combined with the pin’s main function or may be
used instead of it, ie. if the main pin function is not required.
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Interrupt signals may be connected to:
• EX7IN...EX0IN, the fast external interrupt input pins,
• T4IN, T2IN, the timer input pins,
For each of these pins either a positive, a negative, or both a positive and a negative
external transition can be selected to cause an interrupt or PEC service request. The
edge selection is performed in the control register of the peripheral device associated
with the respective port pin. The peripheral must be programmed to a specific operating
mode to allow generation of an interrupt by the external signal. The priority of the
interrupt request is determined by the interrupt control register of the respective
peripheral interrupt source, and the interrupt vector of this source will be used to service
the external interrupt request.
Note: In order to use any of the listed pins as external interrupt input, it must be switched
to input mode via its direction control bit DPx.y in the respective port direction
control register DPx.
Pins T2IN or T4IN can be used as external interrupt input pins when the associated
auxiliary timer T2 or T4 in block GPT1 is configured for capture mode. This mode is
selected by programming the mode control fields T2M or T4M in control registers
T2CON or T4CON to 101B. The active edge of the external input signal is determined by
bit fields T2I or T4I. When these fields are programmed to X01B, interrupt request flags
T2IR or T4IR in registers T2IC or T4IC will be set on a positive external transition at pins
T2IN or T4IN, respectively. When T2I or T4I are programmed to X10B, then a negative
external transition will set the corresponding request flag. When T2I or T4I are
programmed to X11B, both a positive and a negative transition will set the request flag.
In all three cases, the contents of the core timer T3 will be captured into the auxiliary
timer registers T2 or T4 based on the transition at pins T2IN or T4IN. When the interrupt
enable bits T2IE or T4IE are set, a PEC request or an interrupt request for vector T2INT
or T4INT will be generated.
Note: The non-maskable interrupt input pin NMI and the reset input RSTIN provide
another possibility for the CPU to react on an external input signal. NMI and RSTIN
are dedicated input pins, which cause hardware traps.
Table 18 Pins to be used as External Interrupt Inputs
Port Pin Original Function Control Register
P2.7-0/EX7-0IN Fast external interrupt input pin EXICON
P3.7/T2IN Auxiliary timer T2 input pin T2CON
P3.5/T4IN Auxiliary timer T4 input pin T4CON
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6.8.1 Fast External Interrupts
The input pins that may be used for external interrupts are sampled every 16 TCL, ie.
external events are scanned and detected in timeframes of 16 TCL. The C165H provides
8 external interrupt inputs that are sampled every 2 TCL, so external events are captured
faster than with standard interrupt inputs.
The pins of Port 2 (P2.7...P2.0) can individually be programmed to this fast interrupt
mode, where also the trigger transition (rising, falling or both) can be selected. The
External Interrupt Control register EXICON controls this feature for all 8 pins.
EXICON (F1C0H / E0H) ESFR Reset Value: 0000H
Note:
1. The fast external interrupt inputs are sampled every 2 TCL. The interrupt request
arbitration and processing, however, is executed every 8 TCL.
2. In Sleep mode, no clock is available. Therefore sampling is performed with
asynchronous structures.
3. In Sleep mode fast external interrupts as well as the NMI input are controlled for spike
suppression in the System Control Block. Input signals shorter than 10 ns are
suppressed, detection is guaranteed for minimum 150 ns input signals.
6.8.2 External Interrupt Source Control
Fast external interrupts may also have interrupt sources selected from other peripherals.
This function is very advantageous in Slow Down mode or in Sleep mode, if for example
the SSC interface shall be used to wake-up the system. The register EXISEL is used to
switch the receive inputs of the serial interfaces to the fast external interrupts, in order to
detect incomming messages in case of disabled serial interface modules.
The EXISEL register is defined as follows:
Bit Function
EXIxES External Interrupt x Edge Selection Field (x=7...0)
0 0: Fast external interrupts disabled: standard mode
0 1: Interrupt on positive edge (rising)
1 0: Interrupt on negative edge (falling)
1 1: Interrupt on any edge (rising or falling)
54321011 10 987615 14 13 12
rwrwrw
EXI2ES EXI0ESEXI1ES
rwrwrw
EXI7ES EXI5ESEXI6ES
rwrw
EXI3ESEXI4ES
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EXISEL (F1DAH / EDH) ESFR-bReset Value: 0000H
Bit Function
EXI0SS 0 0: Input from default pin. Must be set to ’00’.
0 1: Not allowed.
1 0: Not allowed.
1 1: Not allowed.
EXI1SS 0 0: Input from default pin.Must be set to ’00’.
0 1: Not allowed.
1 0: Not allowed.
1 1: Not allowed.
EXI2SS 0 0: Input from default pin.
0 1: Input from alternate source ASC_RxD @ P3.11.
1 0: Input from default pin ORed with alternate source ASC_RxD @ P3.11.
1 1: Input from default pin ANDed with alternate source ASC_RxD @ P3.11.
EXI3SS 0 0: Input from default pin.
0 1: Input from alternate source SSC_RxD @ P3.9.
1 0: Input from default pin ORed with alternate source SSC_RxD @ P3.9.
1 1: Input from default pin ANDed with alternate source SSC_RxD @ P3.9.
EXI4SS 0 0: Input from default pin.
0 1: Input from alternate source SSC_SCLK @ P3.13.
1 0: Input from default pin ORed with alternate source SSC_SCLK @ P3.13.
1 1: Input from default pin ANDed with alternate source SSC_SCLK @ P3.13.
EXI5SS 0 0: Input from default pin. Must be set to ’00’
0 1: Not allowed.
1 0: Not allowed.
1 1: Not allowed.
EXI6SS 0 0: Input from default pin.
0 1: Input from alternate source IOM-2 @ DCL.
1 0: Input from default pin ORed with alternate source IOM-2 @ DCL.
1 1: Input from default pin ANDed with alternate source IOM-2 @ DCL.
EXI7SS 0 0: Not allowed.
0 1: Input from source RTC_INT.
1 0: Not allowed.
1 1: Not allowed.
54321011 10 987615 14 13 12
rwrwrw
EXI2SS 0000
rwrwrw
01 EXI5SSEXI6SS
rwrw
EXI3SSEXI4SS
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6.8.3 Interrupt Subnode Control
The RTC (Real Time Clock) interrupt T14INT and the PLL/OWD interrupt share one
interrupt node, the XPER3 interrupt node. In order to enable the interrupt handler to
determine the source of that shared interrupt request, the subnode interrupt control
register ISNC is provided. The separate interrupt request and enable flags of register
ISNC (see below) for the PLL (PLLIR, PLLIE) as well as for the RTC (T14IR, T14IE) are
used as shown in Figure 25.
Figure 25 Interrupt Subnode Control for PLL / RTC Interrupts
Note: The Interrupt Service Routine must clear the IR flag in register ISNC manually.
Otherwise no further interrupts can be detected.
All request flags are bit protected.
Diff.
Circuit
ISNC
&
Pulse
Generation
T14
PLLINT
Diff.
Circuit
T14INT &
IE
T14
IR1)
PLL
IE
PLL
IR1)
1 INT
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The ISNC register is defined as follows:
6.8.4 The Interrupt Control Register
The interrupt control registers listed below (FEI7IC..FEI0IC) control the fast external
interrupts of the C165H.
ISNC (F1DEH / EFH) ESFR-bReset Value : 0000H
1514131211109876543210
PLL
IE
PLL
IR
RTC
T14
IE
RTC
T14
IR
Bit Function
T14IR T14 Overflow Interrupt Request Flag
‘0’: No request pending
‘1’: This source has raised an interrupt request
T14IE T14 Overflow Interrupt Enable Control Bit
‘0’: Interrupt request is disabled
‘1’: Interrupt request is enabled
PLLIR PLL Interrupt Request Flag
‘0’: No request pending
‘1’: This source has raised an interrupt request
PLLIE PLL Interrupt Enable Control Bit
‘0’: Interrupt request is disabled
‘1’: Interrupt request is enabled
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FEIxIC (See Table) SFR Reset Value: - - 00HH
Note: Please refer to the general Interrupt Control Register description for an
explanation of the control fields.
Table 19 Fast External Interrupt Control Register Addresses
6.9 Trap Functions
Traps interrupt the current execution similar to standard interrupts. However, trap
functions offer the possibility to bypass the interrupt system's prioritization process in
cases where immediate system reaction is required. Trap functions are not maskable
and always have priority over interrupt requests on any priority level.
The C165H provides two different kinds of trapping mechanisms. Hardware traps are
triggered by events that occur during program execution (eg. illegal access or undefined
opcode), software traps are initiated via an instruction within the current execution flow.
Software Traps
The TRAP instruction is used to cause a software call to an interrupt service routine. The
trap number that is specified in the operand field of the trap instruction determines which
vector location in the address range from 00’0000H through 00’01FCH will be branched
to.
Executing a TRAP instruction causes a similar effect as if an interrupt at the same vector
had occurred. PSW, CSP (in segmentation mode), and IP are pushed on the internal
system stack and a jump is taken to the specified vector location. When segmentation is
enabled and a trap is executed, the CSP for the trap service routine is set to code
segment 0. No Interrupt Request flags are affected by the TRAP instruction.
Register Address External Interrupt
FEI0IC FF88H / C4HEX0IN
FEI1IC FF8AH / C5HEX1IN
FEI2IC FF8CH / C6HEX2IN
FEI3IC FF8EH / C7HEX3IN
FEI4IC FF90H / C8HEX4IN
FEI5IC FF92H / C9HEX5IN
FEI6IC FF94H / CAHEX6IN
FEI7IC FF96H / CBHEX7IN
54321011 10 987615 14 13 12
rw rw----rw rw----
FEIx
IE
FEIx
IR ILVL GLVL
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The interrupt service routine called by a TRAP instruction must be terminated with a
RETI (return from interrupt) instruction to ensure correct operation.
Note: The CPU level in register PSW is not modified by the TRAP instruction, so the
service routine is executed on the same priority level from which it was invoked.
Therefore, the service routine entered by the TRAP instruction can be interrupted
by other traps or higher priority interrupts, other than when triggered by a
hardware trap.
Hardware Traps
Hardware traps are issued by faults or specific system states that occur during runtime
of a program (not identified at assembly time). A hardware trap may also be triggered
intentionally, eg. to emulate additional instructions by generating an Illegal Opcode trap.
The C165H distinguishes eight different hardware trap functions. When a hardware trap
condition has been detected, the CPU branches to the trap vector location for the
respective trap condition. Depending on the trap condition, the instruction which caused
the trap is either completed or cancelled (ie. it has no effect on the system state) before
the trap handling routine is entered.
Hardware traps are non-maskable and always have priority over every other CPU
activity. If several hardware trap conditions are detected within the same instruction
cycle, the highest priority trap is serviced (see table in section “Interrupt System
Structure”).
PSW, CSP (in segmentation mode), and IP are pushed on the internal system stack and
the CPU level in register PSW is set to the highest possible priority level (ie. level 15),
disabling all interrupts. The CSP is set to code segment zero, if segmentation is enabled.
A trap service routine must be terminated with the RETI instruction.
The eight hardware trap functions of the C165H are divided into two classes:
Class A traps are
• external Non-Maskable Interrupt (NMI)
• Stack Overflow
• Stack Underflow trap
These traps share the same trap priority, but have an individual vector address.
Class B traps are
• Undefined Opcode
• Protection Fault
• Illegal Word Operand Access
• Illegal Instruction Access
• Illegal External Bus Access Trap
These traps share the same trap priority, and the same vector address.
The bit-addressable Trap Flag Register (TFR) allows a trap service routine to identify the
kind of trap which caused the exception. Each trap function is indicated by a separate
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request flag. When a hardware trap occurs, the corresponding request flag in register
TFR is set to '1'.
TFR (FFACH / D6H) SFR Reset Value: 0000H
Note: The trap service routine must clear the respective trap flag, otherwise a new trap
will be requested after exiting the service routine. Setting a trap request flag by
software causes the same effects as if it had been set by hardware.
The reset functions (hardware, software, watchdog) may be regarded as a type of trap.
Reset functions have the highest system priority (trap priority III).
Class A traps have the second highest priority (trap priority II), on the 3rd rank are class
B traps, so a class A trap can interrupt a class B trap. If more than one class A trap occur
at a time, they are prioritized internally, with the NMI trap on the highest and the stack
underflow trap on the lowest priority.
All class B traps have the same trap priority (trap priority I). When several class B traps
get active at a time, the corresponding flags in the TFR register are set and the trap
service routine is entered. Since all class B traps have the same vector, the priority of
service of simultaneously occurring class B traps is determined by software in the trap
service routine.
Bit Function
ILLBUS Illegal External Bus Access Flag
An external access has been attempted with no external bus defined.
ILLINA Illegal Instruction Access Flag
A branch to an odd address has been attempted.
ILLOPA Illegal Word Operand Access Flag
A word operand access (read or write) to an odd address has been attempted.
PRTFLT Protection Fault Flag
A protected instruction with an illegal format has been detected.
UNDOPC Undefined Opcode Flag
The currently decoded instruction has no valid C165H opcode.
STKUF Stack Underflow Flag
The current stack pointer value exceeds the content of register STKUN.
STKOF Stack Overflow Flag
The current stack pointer value falls below the content of register STKOV.
NMI Non Maskable Interrupt Flag
A negative transition (falling edge) has been detected on pin NMI.
NMI
54321011 10 987615 14 13 12
rw rw rw rwrw - - --rw ---
STK
UF ILL
BUS
ILL
INA
ILL
OPA
PRT
FLT
UND
OPC
STK
OF - - - - - - --
-rwrw
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A class A trap occurring during the execution of a class B trap service routine will be
serviced immediately. During the execution of a class A trap service routine, however,
any class B trap occurring will not be serviced until the class A trap service routine is
exited with a RETI instruction. In this case, the occurrence of the class B trap condition
is stored in the TFR register, but the IP value of the instruction which caused this trap is
lost.
In the case where e.g. an Undefined Opcode trap (class B) occurs simultaneously with
an NMI trap (class A), both the NMI and the UNDOPC flag is set, the IP of the instruction
with the undefined opcode is pushed onto the system stack, but the NMI trap is executed.
After return from the NMI service routine, the IP is popped from the stack and
immediately pushed again because of the pending UNDOPC trap.
External NMI Trap
Whenever a high to low transition on the dedicated external NMI pin (Non-Maskable
Interrupt) is detected, the NMI flag in register TFR is set and the CPU will enter the NMI
trap routine. The IP value pushed on the system stack is the address of the instruction
following the one after which normal processing was interrupted by the NMI trap.
Stack Overflow Trap
Whenever the stack pointer is decremented to a value which is less than the value in the
stack overflow register STKOV, the STKOF flag in register TFR is set and the CPU will
enter the stack overflow trap routine. Which IP value will be pushed onto the system
stack depends on which operation caused the decrement of the SP. When an implicit
decrement of the SP is made through a PUSH or CALL instruction, or upon interrupt or
trap entry, the IP value pushed is the address of the following instruction. When the SP
is decremented by a subtract instruction, the IP value pushed represents the address of
the instruction after the instruction following the subtract instruction.
For recovery from stack overflow it must be ensured that there is enough excess space
on the stack for saving the current system state (PSW, IP, in segmented mode also CSP)
twice. Otherwise, a system reset should be generated.
Stack Underflow Trap
Whenever the stack pointer is incremented to a value which is greater than the value in
the stack underflow register STKUN, the STKUF flag is set in register TFR and the CPU
will enter the stack underflow trap routine. Again, which IP value will be pushed onto the
system stack depends on which operation caused the increment of the SP. When an
implicit increment of the SP is made through a POP or return instruction, the IP value
pushed is the address of the following instruction. When the SP is incremented by an
add instruction, the pushed IP value represents the address of the instruction after the
instruction following the add instruction.
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Undefined Opcode Trap
When the instruction currently decoded by the CPU does not contain a valid C165H
opcode, the UNDOPC flag is set in register TFR and the CPU enters the undefined
opcode trap routine. The IP value pushed onto the system stack is the address of the
instruction that caused the trap.
This can be used to emulate unimplemented instructions. The trap service routine can
examine the faulting instruction to decode operands for unimplemented opcodes based
on the stacked IP. In order to resume processing, the stacked IP value must be
incremented by the size of the undefined instruction, which is determined by the user,
before a RETI instruction is executed.
Protection Fault Trap
Whenever one of the special protected instructions is executed where the opcode of that
instruction is not repeated twice in the second word of the instruction and the byte
following the opcode is not the complement of the opcode, the PRTFLT flag in register
TFR is set and the CPU enters the protection fault trap routine. The protected
instructions include DISWDT, EINIT, IDLE, PWRDN, SRST, and SRVWDT. The IP value
pushed onto the system stack for the protection fault trap is the address of the instruction
that caused the trap.
Illegal Word Operand Access Trap
Whenever a word operand read or write access is attempted to an odd byte address, the
ILLOPA flag in register TFR is set and the CPU enters the illegal word operand access
trap routine. The IP value pushed onto the system stack is the address of the instruction
following the one which caused the trap.
Illegal Instruction Access Trap
Whenever a branch is made to an odd byte address, the ILLINA flag in register TFR is
set and the CPU enters the illegal instruction access trap routine. The IP value pushed
onto the system stack is the illegal odd target address of the branch instruction.
Illegal External Bus Access Trap
Whenever the CPU requests an external instruction fetch, data read or data write, and
no external bus configuration has been specified, the ILLBUS flag in register TFR is set
and the CPU enters the illegal bus access trap routine. The IP value pushed onto the
system stack is the address of the instruction following the one which caused the trap.
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Parallel Ports
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- EXCERPT -
7 Parallel Ports
In order to accept or generate single external control signals or parallel data, the C165H
provides up to 72 parallel I/O lines. The C165H features Port 0 (inculdes 8 bit P0H and
8 bit P0L), Port 1 (8 bit P1H and 8 bit P1L), Port 2 (8 bit), Port 3 (11 bit), Port 4 (7 bit),
Port 6 (8 bit) and Port 7 (6 bit).
These port lines may be used for general purpose Input/Output controlled via software
or may be used implicitly by C165H’s integrated peripherals or the External Bus
Controller.
All port lines are bit addressable, and all input/output lines are individually (bit-wise)
programmable as inputs or outputs via direction registers. The I/O ports are true
bidirectional ports which are switched to high impedance state when configured as
inputs. The output drivers of the I/O ports (P0H, P1, P2, P3, P4, P6, P7) can be
configured (pin by pin) for push/pull operation or open-drain operation via control
registers. The logic level of a pin is clocked into the input latch once per state time,
regardless whether the port is configured for input or output.
A write operation to a port pin configured as an input (DPx.y = ’0’) causes the value to
be written into the port output latch, while a read operation returns the latched state of
the pin itself. A read-modify-write operation reads the value of the pin, modifies it, and
writes it back to the output latch.
Writing to a pin configured as an output (DPx.y=‘1’) causes the output latch and the pin
to have the written value, since the output buffer is enabled. Reading this pin returns the
value of the output latch. A read-modify-write operation reads the value of the output
latch, modifies it, and writes it back to the output latch, thus also modifying the level at
the pin.
C165H
Parallel Ports
Data Sheet 125 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 26 SFRs and Pins associated with the Parallel Ports
In the C165H certain ports provide Open Drain Control, which allows to switch the output
driver of a port pin from a push/pull configuration to an open drain configuration. In push/
pull mode a port output driver has an upper and a lower transistor, thus it can actively
drive the line either to a high or a low level. In open drain mode the upper transistor is
always switched off, and the output driver can only actively drive the line to a low level.
When writing a ‘1’ to the port latch, the lower transistor is switched off and the output
enters a high-impedance state. The high level must then be provided by an external
pullup device. With this feature, it is possible to connect several port pins together to a
Wired-AND configuration, saving external glue logic and/or additional software overhead
for enabling/disabling output signals.
This feature is implemented for all ports except P0L, and is controlled through the
respective Open Drain Control Registers ODPx. These registers allow the individual bit-
wise selection of the open drain mode for each port line. If the respective control bit
ODPx.y is ‘0’ (default after reset), the output driver is in the push/pull mode. If ODPx.y is
‘1’, the open drain configuration is selected. Note that all ODPx registers are located in
the ESFR space.
ODP2
ODP7
ODP3
ODP1L
ODP1H
ODP4
ODP6
ODP0H
DP2
DP3
DP7
DP0L
DP0H
DP4
DP1H
DP1L
DP6
P2
P3
P7
P0L
P0H
P4
P1L
P1H
P6
Data Input / Output
Registers
Direction Control
Registers
Open Drain Control
Registers
PxPUDSEL:
P0L, P0H, P1L,
P1H, P2, P3,
P4, P6, P7
PxPUDEN:
P0L, P0H, P1L,
P1H, P2, P3,
P4, P6, P7
PxPHEN:
P0L, P0H, P1L,
P1H, P2, P3,
P4, P6, P7
Pull Up/Down Control
Registers
C165H
Parallel Ports
Data Sheet 126 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 27 Output Drivers in Push/Pull Mode and in Open Drain Mode
Alternate Port Functions
Each port line has one programmable alternate input or output function associated.
PORT0 and PORT1 may be used as the address and data lines when accessing
external memory.
Port 2 is used for fast external interrupt inputs.
Port 3 includes alternate input/output functions of timers, serial interfaces, the optional
bus control signal BHE/WRH and the system clock output (CLKOUT).
Port 4 outputs the additional segment address bits A22/A19/A17...A16 in systems where
more than 64 KBytes of memory are to be accessed directly.
Port 6 provides the optional chip select outputs and the bus arbitration lines.
Port 7 is used for general purpose I/Os.
If an alternate output function of a pin is to be used, the direction of this pin must be
programmed for output (DPx.y=‘1’), except for some signals that are used directly after
reset and are configured automatically. Otherwise the pin remains in the high-impedance
state and is not effected by the alternate output function. The respective port latch should
hold a ‘1’, because its output is ANDed with the alternate output data.
Note: DP0L and, if a 16 bit external XBus data bus is used, also DP0H must be ’0’ as
long as the XBUS is active.
If an alternate input function of a pin is used, the direction of the pin must be programmed
for input (DPx.y=‘0’) if an external device is driving the pin. The input direction is the
default after reset. If no external device is connected to the pin, however, one can also
set the direction for this pin to output. In this case, the pin reflects the state of the port
output latch. Thus, the alternate input function reads the value stored in the port output
latch. This can be used for testing purposes to allow a software trigger of an alternate
input function by writing to the port output latch.
MCS01975
Open Drain Output Driver
External
Pullup
Q
Push/Pull Output Driver
Q
Pin Pin
C165H
Parallel Ports
Data Sheet 127 2001-04-19
PRELIMINARY
- EXCERPT -
On most of the port lines, the user software is responsible for setting the proper direction
when using an alternate input or output function of a pin. This is done by setting or
clearing the direction control bit DPx.y of the pin before enabling the alternate function.
There are port lines, however, where the direction of the port line is switched
automatically. For instance, in the multiplexed external bus modes of PORT0, the
direction must be switched several times for an instruction fetch in order to output the
addresses and to input the data. Obviously, this cannot be done through instructions. In
these cases, the direction of the port line is switched automatically by hardware if the
alternate function of such a pin is enabled.
Note: In this case, make sure DP0 is set to ’0’ signal.
To determine the appropriate level of the port output latches, check how the alternate
data output is combined with the respective port latch output.
There is one basic structure for all port lines with only an alternate input function. Port
lines with only an alternate output function, however, have different structures due to the
way the direction of the pin is switched and depending on whether the pin is accessible
by the user software or not in the alternate function mode.
All port lines that are not used for these alternate functions may be used as general
purpose I/O lines. When using port pins for general purpose output, the initial output
value should be written to the port latch prior to enabling the output drivers, in order to
avoid undesired transitions on the output pins. This applies to single pins as well as to
pin groups (see examples below).
OUTPUT_ENABLE_SINGLE_PIN:
BSET P4.0 ;Initial output level is ’high’
BSET DP4.0 ;Switch on the output driver
OUTPUT_ENABLE_PIN_GROUP:
BFLDL P4, #05H, #05H ;Initial output level is ’high’
BFLDL DP4, #05H, #05H ;Switch on the output drivers
Each of these ports and the alternate input and output functions are described in detail
in the following subsections.
7.1 PORT0
The two 8-bit ports P0H and P0L represent the higher and lower part of PORT0,
respectively. Both halfs of PORT0 can be written (eg. via a PEC transfer) without
effecting the other half.
C165H
Parallel Ports
Data Sheet 128 2001-04-19
PRELIMINARY
- EXCERPT -
If this port is used for general purpose I/O, the direction of each line can be configured
via the corresponding direction registers DP0H and DP0L.
Each port line of PORT0H can be switched into push/pull or open drain mode via the
open drain control register ODP0H.
For port pins configured as input (via DP0x or alternate function), an internal pull
transistor is connected to the pad if register P0xPUDEN = ’1’, no matter whether the
C165H is in normal operation mode or in power down mode. Either pulldown transistor
or pullup transistor will be selected via P0xPUDSEL.
For port pins configured as output, the internal pull transistors are always disabled. The
output driver is disabled in power down mode unless P0xPHEN = ’1’.
After reset, P0xPUDEN and P0xPUDSEL are set to HIGH signal, thereby providing the
default reset configuration 1111H to the C165H during reset.
Note: While this feature allows the user to start the C165H after reset in default
configuration without external pull devices, the default configuration may be
overwritten by stronger external pulldown devices. In this case, Software should
disable the internal pull’s after reset (see also next chapter ’Alternate Function’).
C165H
Parallel Ports
Data Sheet 129 2001-04-19
PRELIMINARY
- EXCERPT -
P0L (FF00H / 80H) SFR Reset Value: - - 00H
P0H (FF02H / 81H) SFR Reset Value: - - 00H
DP0L (F100H / 80H) ESFR Reset Value: - - 00H
DP0H (F102H / 81H) ESFR Reset Value: - - 00H
Bit Function
P0X.y Port data register P0H or P0L bit y
Bit Function
DP0X.y Port direction register DP0H or DP0L bit y
DP0X.y = 0: Port line P0X.y is an input (high-impedance)
DP0X.y = 1: Port line P0X.y is an output
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
P0L.0P0L.1P0L.2P0L.3P0L.4P0L.5P0L.6P0L.7
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
P0H.0P0H.1P0H.2P0H.3P0H.4P0H.5P0H.6P0H.7
DP0L
.0
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
DP0L
.7 DP0L
.6 DP0L
.5 DP0L
.4 DP0L
.3 DP0L
.2 DP0L
.1
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
DP0H
.7 DP0H
.6 DP0H
.5 DP0H
.4 DP0H
.3 DP0H
.2 DP0H
.1 DP0H
.0
C165H
Parallel Ports
Data Sheet 130 2001-04-19
PRELIMINARY
- EXCERPT -
ODP0H (FE22H / 11H) SFR Reset Value: - - 00H
P0LPUDSEL (FE60H / 30H) SFR Reset Value: - - FFH
P0HPUDSEL (FE62H / 31H) SFR Reset Value: - - FFH
Bit Function
ODP0H.y Port0H Open Drain control register bit y
ODP0H.y = 0: Port line P0H.y output driver in push/pull mode
ODP0H.y = 1: Port line P0H.y output driver in open drain mode
Bit Function
P0xPUDSEL.y Pulldown/Pullup Selection
P0xPUDSEL.y = 0: internal programmable pulldown transistor is selected
P0xPUDSEL.y = 1: internal programmable pullup transistor is selected
54321011 10 987615 14 13 12
rw rw rw rw rw rw- - - - rw rw----
ODP0
H.7 ODP0
H.6 ODP0
H.5 ODP0
H.4 ODP0
H.3 ODP0
H.2 ODP0
H.1 ODP0
H.0
54321011 10 987615 14 13 12
rw rw rw rw rw rw- - - - rw rw----
P0L
PUD
SEL.7
P0L
PUD
SEL.6
P0L
PUD
SEL.5
P0L
PUD
SEL.4
P0L
PUD
SEL.3
P0L
PUD
SEL.2
P0L
PUD
SEL.1
P0L
PUD
SEL.0
54321011 10 987615 14 13 12
rw rw rw rw rw rw- - - - rw rw----
P0H
PUD
SEL.7
P0H
PUD
SEL.6
P0H
PUD
SEL.5
P0H
PUD
SEL.4
P0H
PUD
SEL.3
P0H
PUD
SEL.2
P0H
PUD
SEL.1
P0H
PUD
SEL.0
C165H
Parallel Ports
Data Sheet 131 2001-04-19
PRELIMINARY
- EXCERPT -
P0LPUDEN (FE64H / 32H) SFR Reset Value: - - FFH
P0HPUDEN (FE66H / 33H) SFR Reset Value: - - FFH
P0LPHEN (FE68H / 34H) SFR Reset Value: - - 00H
P0HPHEN (FE6AH / 35H) SFR Reset Value: - - 00H
Bit Function
P0xPUDEN.y Pulldown/Pullup Enable
P0xPUDEN.y = 0: internal programmable pull transistor is disabled
P0xPUDEN.y = 1: internal programmable pull transistor is enabled
Bit Function
P0xPHEN.y Output Driver Enable in Power Down Mode
P0xPHEN.y = 0: output driver is disabled in power down mode
P0xPHEN.y = 1: output driver is enabled in power down mode
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
P0L
PUD
EN.7
P0L
PUD
EN.6
P0L
PUD
EN.5
P0L
PUD
EN.4
P0L
PUD
EN.3
P0L
PUD
EN.2
P0L
PUD
EN.1
P0L
PUD
EN.0
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
P0H
PUD
EN.7
P0H
PUD
EN.6
P0H
PUD
EN.5
P0H
PUD
EN.4
P0H
PUD
EN.3
P0H
PUD
EN.2
P0H
PUD
EN.1
P0H
PUD
EN.0
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
P0L
PHEN
.7
P0L
PHEN
.6
P0L
PHEN
.5
P0L
PHEN
.4
P0L
PHEN
.3
P0L
PHEN
.2
P0L
PHEN
.1
P0L
PHEN
.0
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
P0H
PHEN
.7
P0H
PHEN
.6
P0H
PHEN
.5
P0H
PHEN
.4
P0H
PHEN
.3
P0H
PHEN
.2
P0H
PHEN
.1
P0H
PHEN
.0
C165H
Parallel Ports
Data Sheet 132 2001-04-19
PRELIMINARY
- EXCERPT -
7.1.1 Alternate Functions of PORT0
When an external bus is enabled, PORT0 is used as data bus or address/data bus.
Note that an external 8-bit demultiplexed bus only uses P0L, while P0H is free for I/O
(provided that no other bus mode is enabled).
PORT0 is also used to select the system startup configuration. During reset, PORT0 is
configured to input, and each line is held high through an internal pullup device. Each
line can now be individually pulled to a low level (see DC-level specifications in the
respective Data Sheets) through an external pulldown device. A default configuration is
selected when the respective PORT0 lines are at a high level. Through pulling individual
lines to a low level, this default can be changed according to the needs of the
applications.
The internal pullup devices are designed such that an external pulldown resistors (see
specification) can be used to apply a correct low level. These external pulldown resistors
can remain connected to the PORT0 pins also during normal operation, however, care
has to be taken such that they do not disturb the normal function of PORT0 (this might
be the case, for example, if the external resistor is too strong).
With the end of reset, the selected bus configuration will be written to the BUSCON0
register. The configuration of the high byte of PORT0, will be copied into the special
register RP0H. This read-only register holds the selection for the number of chip selects
and segment addresses. Software can read this register in order to react according to
the selected configuration, if required.
Note: When the reset is terminated, the internal pullup devices must be switched off by
Software and PORT0 will be switched to the appropriate operating mode.
During external accesses in multiplexed bus modes PORT0 first outputs the 16-bit intra-
segment address as an alternate output function. PORT0 is then switched to high-
impedance input mode to read the incoming instruction or data. In 8-bit data bus mode,
two memory cycles are required for word accesses, the first for the low byte and the
second for the high byte of the word. During write cycles PORT0 outputs the data byte
or word after outputting the address.
During external accesses in demultiplexed bus modes PORT0 reads the incoming
instruction or data word or outputs the data byte or word.
C165H
Parallel Ports
Data Sheet 133 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 28 PORT0 I/O and Alternate Functions
When an external bus mode is enabled, the direction of the port pin and the loading of
data into the port output latch are controlled by the bus controller hardware. The input of
the port output latch is disconnected from the internal bus and is switched to the line
labeled “Alternate Data Output” via a multiplexer. The alternate data can be the 16-bit
intrasegment address or the 8/16-bit data information. The incoming data on PORT0 is
read on the line “Alternate Data Input”. While an external bus mode is enabled, the user
software should not write to the port output latch, otherwise unpredictable results may
occur. When the external bus modes are disabled, the contents of the direction register
last written by the user becomes active.
Figure 29 shows the structure of a PORT0 pin.
P0H.7
P0H.6
P0H.5
P0H.4
P0H.3
P0H.2
P0H.1
P0H.0
P0L.7
P0L.6
P0L.5
P0L.4
P0L.3
P0L.2
P0L.1
P0L.0
PORT0 D7
D6
D5
D4
D3
D2
D1
D0
P0H
P0L
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
AD15
AD14
AD13
AD12
AD11
AD10
AD9
AD8
AD7
AD6
AD5
AD4
AD3
AD2
AD1
AD0
AD15
AD14
AD13
AD12
AD11
AD10
AD9
AD8
AD7
AD6
AD5
AD4
AD3
AD2
AD1
AD0
Alternate Function a) b) c) d)
General Purpose
Input/Output 8-bit
Demux Bus 16-bit
Demux Bus 8-bit
MUX Bus 16-bit
MUX Bus
C165H
Parallel Ports
Data Sheet 134 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 29 Block Diagram of a PORT0 Pin
7.2 PORT1
The two 8-bit ports P1H and P1L represent the higher and lower part of PORT1,
respectively. Both halfs of PORT1 can be written (eg. via a PEC transfer) without
effecting the other half.
If this port is used for general purpose I/O, the direction of each line can be configured
via the corresponding direction registers DP1H and DP1L.
Each port line can be switched into push/pull or open drain mode via the open drain
control register ODP1L and ODP1H.
For port pins configured as input (via DP1x or alternate function), an internal pull
transistor is connected to the pad if register P1xPUDEN = ’1’, no matter wheter the
C165H is in normal operation mode or in power down mode. Either pulldown transistor
or pullup transistor will be selected via P1xPUDSEL.
MCB02231
Output
Buffer
MUX
1
0
Alternate
Data
Output
Latch
Port Output
0
1
MUX
Write P0H.y/P0L.y
Read P0H.y/P0L.y
Enable
Function
Alternate
0
1
MUX
Read DP0H.y/DP0L.y
Write DP0H.y/DP0L.y
Direction
Input
Latch
Clock
Latch
s
u
B
l
a
n
r
e
t
n
Ι
P0H.y
P0L.y
Direction
Alternate
y = 7...0
C165H
Parallel Ports
Data Sheet 135 2001-04-19
PRELIMINARY
- EXCERPT -
For port pins configured as output, the internal pull transistors are always disabled. The
output driver is disabled in power down mode unless P1xPHEN = ’1’.
After reset, P1xPUDEN and P1xPUDSEL are set to LOW signal.
P1L (FF04H / 82H) SFR Reset Value: - - 00H
P1H (FF06H / 83H) SFR Reset Value: - - 00H
DP1L (F104H / 82H) ESFR Reset Value: - - 00H
DP1H (F106H / 83H) ESFR Reset Value: - - 00H
ODP1L (FE24H / 12H) SFR Reset Value: - - 00H
Bit Function
P1X.y Port data register P1H or P1L bit y
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
P1L.0P1L.1P1L.2P1L.3P1L.4P1L.5P1L.6P1L.7
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
P1H.0P1H.1P1H.2P1H.3P1H.4P1H.5P1H.6P1H.7
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
DP1L
.7 DP1L
.6 DP1L
.5 DP1L
.4 DP1L
.3 DP1L
.2 DP1L
.1 DP1L
.0
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
DP1H
.7 DP1H
.6 DP1H
.5 DP1H
.4 DP1H
.3 DP1H
.2 DP1H
.1 DP1H
.0
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
ODP1
L.7 ODP1
L.6 ODP1
L.5 ODP1
L.4 ODP1
L.3 ODP1
L.2 ODP1
L.1 ODP1
L.0
C165H
Parallel Ports
Data Sheet 136 2001-04-19
PRELIMINARY
- EXCERPT -
ODP1H (FE26H / 13H) SFR Reset Value: - - 00H
P1LPUDSEL (FE6CH / 36H) SFR Reset Value: - - 00H
P1HPUDSEL (FE6EH / 37H) SFR Reset Value: - - 00H
Bit Function
DP1X.y Port direction register DP1H or DP1L bit y
DP1X.y = 0: Port line P1X.y is an input (high-impedance)
DP1X.y = 1: Port line P1X.y is an output
Bit Function
ODP1x.y Port1x Open Drain control register bit y
ODP1x.y = 0: Port line P1x.y output driver in push/pull mode
ODP1x.y = 1: Port line P1x.y output driver in open drain mode
Bit Function
P1xPUDSEL.y Pulldown/Pullup Selection
P1xPUDSEL.y = 0: internal programmable pulldown transistor is selected
P1xPUDSEL.y = 1: internal programmable pullup transistor is selected
54321011 10 987615 14 13 12
rw rw rw rw rw rw- - - - rw rw----
ODP1
H.7 ODP1
H.6 ODP1
H.5 ODP1
H.4 ODP1
H.3 ODP1
H.2 ODP1
H.1 ODP1
H.0
54321011 10 987615 14 13 12
rw rw rw rw rw rw- - - - rw rw----
P1L
PUD
SEL.7
P1L
PUD
SEL.6
P1L
PUD
SEL.5
P1L
PUD
SEL.4
P1L
PUD
SEL.3
P1L
PUD
SEL.2
P1L
PUD
SEL.1
P1L
PUD
SEL.0
54321011 10 987615 14 13 12
rw rw rw rw rw rw- - - - rw rw----
P1H
PUD
SEL.7
P1H
PUD
SEL.6
P1H
PUD
SEL.5
P1H
PUD
SEL.4
P1H
PUD
SEL.3
P1H
PUD
SEL.2
P1H
PUD
SEL.1
P1H
PUD
SEL.0
C165H
Parallel Ports
Data Sheet 137 2001-04-19
PRELIMINARY
- EXCERPT -
P1LPUDEN (FE70H / 38H) SFR Reset Value: - - 00H
P1HPUDEN (FE72H / 39H) SFR Reset Value: - - 00H
P1LPHEN (FE74H / 3AH) SFR Reset Value: - - 00H
P1HPHEN (FE76H / 3BH) SFR Reset Value: - - 00H
Bit Function
P1xPUDEN.y Pulldown/Pullup Enable
P1xPUDEN.y = 0: internal programmable pull transistor is disabled
P1xPUDEN.y = 1: internal programmable pull transistor is enabled
Bit Function
P1xPHEN.y Output Driver Enable in Power Down Mode
P1xPHEN.y = 0: output driver is disabled in power down mode
P1xPHEN.y = 1: output driver is enabled in power down mode
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
P1L
PUD
EN.7
P1L
PUD
EN.6
P1L
PUD
EN.5
P1L
PUD
EN.4
P1L
PUD
EN.3
P1L
PUD
EN.2
P1L
PUD
EN.1
P1L
PUD
EN.0
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
P1H
PUD
EN.7
P1H
PUD
EN.6
P1H
PUD
EN.5
P1H
PUD
EN.4
P1H
PUD
EN.3
P1H
PUD
EN.2
P1H
PUD
EN.1
P1H
PUD
EN.0
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
P1L
PHEN
.7
P1L
PHEN
.6
P1L
PHEN
.5
P1L
PHEN
.4
P1L
PHEN
.3
P1L
PHEN
.2
P1L
PHEN
.1
P1L
PHEN
.0
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
P1H
PHEN
.7
P1H
PHEN
.6
P1H
PHEN
.5
P1H
PHEN
.4
P1H
PHEN
.3
P1H
PHEN
.2
P1H
PHEN
.1
P1H
PHEN
.0
C165H
Parallel Ports
Data Sheet 138 2001-04-19
PRELIMINARY
- EXCERPT -
7.2.1 Alternate Functions of PORT1
When a demultiplexed external bus is enabled, PORT1 is used as address bus.
Note that demultiplexed bus modes use PORT1 as a 16-bit port. Otherwise all 16 port
lines can be used for general purpose I/O.
During external accesses in demultiplexed bus modes PORT1 outputs the 16-bit intra-
segment address as an alternate output function.
During external accesses in multiplexed bus modes, when no BUSCON register selects
a demultiplexed bus mode, PORT1 is not used and is available for general purpose I/O.
Figure 30 PORT1 I/O and Alternate Functions
When an external bus mode is enabled, the direction of the port pin and the loading of
data into the port output latch are controlled by the bus controller hardware. The input of
the port output latch is disconnected from the internal bus and is switched to the line
labeled “Alternate Data Output” via a multiplexer. The alternate data is the 16-bit
intrasegment address. While an external bus mode is enabled, the user software should
not write to the port output latch, otherwise unpredictable results may occur. When the
external bus modes are disabled, the contents of the direction register last written by the
user becomes active.
P1H.7
P1H.6
P1H.5
P1H.4
P1H.3
P1H.2
P1H.1
P1H.0
P1L.7
P1L.6
P1L.5
P1L.4
P1L.3
P1L.2
P1L.1
P1L.0
PORT1
P1H
P1L
A15
A14
A13
A12
A11
A10
A9
A8
A7
A6
A5
A4
A3
A2
A1
A0
Alternate Function a)
General Purpose
Input/Output 8/16-bit
Demux Bus
C165H
Parallel Ports
Data Sheet 139 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 31 shows the structure of a PORT1 pin.
Figure 31 Block Diagram of a PORT1 Pin
7.3 PORT2
In the C165H Port 2 is an 8 -bit port. If Port 2 is used for general purpose I/O, the direction
of each line can be configured via the corresponding direction register DP2. Each port
line can be switched into push/pull or open drain mode via the open drain control register
ODP2.
For port pins configured as input (via DP2 or alternate function), an internal pull transistor
is connected to the pad if register P2PUDEN = ’1’, no matter wheter the C165H is in
normal operation mode or in power down mode. Either pulldown transistor or pullup
transistor will be selected via P2PUDSEL.
For port pins configured as output, the internal pull transistors are always disabled. The
output driver is disabled in power down mode unless P2PHEN = ’1’.
MCB02232
Output
Buffer
MUX
1
0
Alternate
Data
Output
Latch
Port Output
0
1
MUX
Write P1H.y/P1L.y
Read P1H.y/P1L.y
Enable
Function
Alternate
0
1
MUX
Read DP1H.y/DP1L.y
Write DP1H.y/DP1L.y
Direction
Input
Latch
Clock
Latch
s
u
B
l
a
n
r
e
t
n
Ι
P1H.y
P1L.y
’1’
y = 7...0
C165H
Parallel Ports
Data Sheet 140 2001-04-19
PRELIMINARY
- EXCERPT -
After reset, P2PUDEN and P2PUDSEL are set to LOW signal.
P2 (FFC0H / E0H) SFR Reset Value: - - 00H
DP2 (FFC2H / E1H) SFR Reset Value: - - 00H
ODP2 (F1C2H / E1H) ESFR Reset Value: - - 00H
Bit Function
P2.y Port data register P2 bit y
Bit Function
DP2.y Port direction register DP2 bit y
DP2.y = 0: Port line P2.y is an input (high-impedance)
DP2.y = 1: Port line P2.y is an output
Bit Function
ODP2.y Port 2 Open Drain control register bit y
ODP2.y = 0: Port line P2.y output driver in push/pull mode
ODP2.y = 1: Port line P2.y output driver in open drain mode
P2.0P2.1P2.2P2.4P2.5P2.6
54321011 10 987615 14 13 12
rw rw rw rw rw rw- - - - rw rw----
P2.7 P2.3
DP2.0DP2.1DP2.2DP2.4DP2.5DP2.6
54321011 10 987615 14 13 12
rw rw rw rw rw rw- - - - rw rw----
DP2.7 DP2.3
54321011 10 987615 14 13 12
rw rw rw rw rw rw- - - - rw rw----
ODP2
.7 ODP2
.6 ODP2
.5 ODP2
.4 ODP2
.3 ODP2
.2 ODP2
.1 ODP2
.0
C165H
Parallel Ports
Data Sheet 141 2001-04-19
PRELIMINARY
- EXCERPT -
P2PUDSEL (FE78H / 3CH) SFR Reset Value: - - 00H
P2PUDEN (FE7AH / 3DH) SFR Reset Value: - - 00H
P2PHEN (FE7CH / 3EH) SFR Reset Value: - - 00H
Bit Function
P2PUDSEL.y Pulldown/Pullup Selection
P2PUDSEL.y = 0: internal programmable pulldown transistor is selected
P2PUDSEL.y = 1: internal programmable pullup transistor is selected
Bit Function
P2PUDEN.y Pulldown/Pullup Enable
P2PUDEN.y = 0: internal programmable pull transistor is disabled
P2PUDEN.y = 1: internal programmable pull transistor is enabled
Bit Function
P2PHEN.y Output Driver Enable in Power Down Mode
P2PHEN.y = 0: output driver is disabled in power down mode
P2PHEN.y = 1: output driver is enabled in power down mode
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
P2
PUD
SEL.7
P2
PUD
SEL.6
P2
PUD
SEL.5
P2
PUD
SEL.4
P2
PUD
SEL.3
P2
PUD
SEL.2
P2
PUD
SEL.1
P2
PUD
SEL.0
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
P2
PUD
EN.7
P2
PUD
EN.6
P2
PUD
EN.5
P2
PUD
EN.4
P2
PUD
EN.3
P2
PUD
EN.2
P2
PUD
EN.1
P2
PUD
EN.0
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
P2
PHEN
.7
P2
PHEN
.6
P2
PHEN
.5
P2
PHEN
.4
P2
PHEN
.3
P2
PHEN
.2
P2
PHEN
.1
P2
PHEN
.0
C165H
Parallel Ports
Data Sheet 142 2001-04-19
PRELIMINARY
- EXCERPT -
7.3.1 Alternate Functions of PORT2
All Port 2 lines (P2.7..P2.0) can serve as Fast External Interrupt inputs (EX7IN...EX0IN).
Table 20 summarizes the alternate functions of Port 2.
Table 20 Port 2 Alternate Functions: Fast External Interrupts
Figure 32 Port 2 I/O and Alternate Functions
The pins of Port 2 combine internal bus data and alternate data output before the port
latch input.
Note: As opposed to the C165H, in other existing Infineon C16x devices EX0IN is
assigned to P2.8, EX1IN is assigned to P2.9 ... and EX7IN is assigned to P2.15
using the higher byte of Port 2 instead of using the lower byte of Port 2.
Port 2 Pin Alternate Function
P2.0
P2.1
P2.2
P2.3
P2.4
P2.5
P2.6
P2.7
EX0IN Fast External Interrupt 0 Input
EX1IN Fast External Interrupt 1 Input
EX2IN Fast External Interrupt 2 Input
EX3IN Fast External Interrupt 3 Input
EX4IN Fast External Interrupt 4 Input
EX5IN Fast External Interrupt 5 Input
EX6IN Fast External Interrupt 6 Input
EX7IN Fast External Interrupt 7 Input
-
-
-
-
-
-
-
-
P2.7
P2.6
P2.5
P2.4
P2.3
P2.2
P2.1
P2.0
Port 2
-
-
-
-
-
-
-
-
EX7IN
EX6IN
EX5IN
EX4IN
EX3IN
EX2IN
EX1IN
EX0IN
Alternate Function a)
General Purpose
Input/Output Fast External
Interrupt Input
C165H
Parallel Ports
Data Sheet 143 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 33 Block Diagram of a Port 2 Pin (y = 7...0)
MCB02230
Output
Buffer
Alternate
Data Input
Latch
Port Output
0
1
MUX
Write P2.y
Read P2.y
Read DP2.y
Write DP2.y
Direction
Write ODP2.y
Read ODP2.y
Open Drain
Latch
Input
Latch
Clock
Latch
s
u
B
l
a
n
r
e
t
n
Ι
P2.y
XzIn
C165H
Parallel Ports
Data Sheet 144 2001-04-19
PRELIMINARY
- EXCERPT -
7.4 PORT3
If this 11-bit port is used for general purpose I/O, the direction of each line can be
configured via the corresponding direction register DP3. Each port lines can be switched
into push/pull or open drain mode via the open drain control register ODP3.
Note: Due to pin limitations register bit P3.0..P3.2, P3.4 and P3.14 is not connected to
an output pin. The Port 3 bit-assignment is not consecutive to for compatibility with
other C16x devices.
For port pins configured as input (via DP3 or alternate function), an internal pull transistor
is connected to the pad if register P3PUDEN = ’1’, no matter wheter the C165H is in
normal operation mode or in power down mode. Either pulldown transistor or pullup
transistor will be selected via P3PUDSEL.
For port pins configured as output, the internal pull transistors are always disabled. The
output driver is disabled in power down mode unless P3PHEN = ’1’.
After reset, P3PUDEN and P3PUDSEL are set to LOW signal.
P3 (FFC4H / E2H) SFRReset Value: 0000H
Bit Function
P3.y Port data register P3 bit y
54321011 10 987615 14 13 12
rw -rw - - -rw rw rw rw rw rwrw -rw rw
---P3.3-P3.5P3.6P3.7P3.8P3.9P3.10P3.11P3.12P3.13-P3.15
C165H
Parallel Ports
Data Sheet 145 2001-04-19
PRELIMINARY
- EXCERPT -
DP3 (FFC6H / E3H) SFR Reset Value: 0000H
ODP3 (F1C6H / E3H) ESFR Reset Value: 0000H
P3PUDSEL (FE7EH / 3FH) SFR Reset Value: - - 00H
Bit Function
DP3.y Port direction register DP3 bit y
DP3.y = 0: Port line P3.y is an input (high-impedance)
DP3.y = 1: Port line P3.y is an output
Bit Function
ODP3.y Port 3 Open Drain control register bit y
ODP3.y = 0: Port line P3.y output driver in push/pull mode
ODP3.y = 1: Port line P3.y output driver in open drain mode
Bit Function
P3PUDSEL.y Pulldown/Pullup Selection
P3PUDSEL.y = 0: internal programmable pulldown transistor is selected
P3PUDSEL.y = 1: internal programmable pullup transistor is selected
-- -
54321011 10 987615 14 13 12
rw -rw ---rw rw rw rw rw rwrw -rw rw
DP3
.13 DP3
.11 DP3
.10 DP3
.9 DP3
.8 DP3
.7 DP3
.6 DP3
.5 - DP3
.3 - - -
-DP3
.12
DP3
.15
-- -
54321011 10 987615 14 13 12
rw -rw ---rw rw rw rw rw rwrw -rw rw
ODP3
.13 ODP3
.11 ODP3
.10 ODP3
.9 ODP3
.8 ODP3
.7 ODP3
.6 ODP3
.5 - ODP3
.3 - - -
-
ODP3
.15 ODP3
.12
54321011 10 987615 14 13 12
P3PU
DSEL.
15
P3PU
DSEL.
13
P3PU
DSEL.
5
P3PU
DSEL.
6
P3PU
DSEL.
7
P3PU
DSEL.
8
P3PU
DSEL.
3
P3PU
DSEL.
9
P3PU
DSEL.
10
P3PU
DSEL.
11
-----
rw -rw ---rw rw rw rw rw rwrw -rw rw
P3PU
DSEL.
12
C165H
Parallel Ports
Data Sheet 146 2001-04-19
PRELIMINARY
- EXCERPT -
P3PUDEN (FE80H / 40H) SFR Reset Value: - - 00H
P3PHEN (FE82H / 41H) SFR Reset Value: - - 00H
Bit Function
P3PUDEN.y Pulldown/Pullup Enable
P3PUDEN.y = 0: internal programmable pull transistor is disabled
P3PUDEN.y = 1: internal programmable pull transistor is enabled
Bit Function
P3PHEN.y Output Driver Enable in Power Down Mode
P3PHEN.y = 0: output driver is disabled in power down mode
P3PHEN.y = 1: output driver is enabled in power down mode
54321011 10 987615 14 13 12
P3PU
DEN.
15
P3PU
DEN.
13
P3PU
DEN.
5
P3PU
DEN.
6
P3PU
DEN.
7
P3PU
DEN.
8
P3PU
DEN.
3
P3PU
DEN.
9
P3PU
DEN.
10
P3PU
DEN.
11
-----
rw -rw - - -rw rw rw rw rw rwrw -rw rw
P3PU
DEN.
12
54321011 10 987615 14 13 12
P3
PHEN
.15
P3
PHEN
.13
P3
PHEN
.5
P3
PHEN
.6
P3
PHEN
.7
P3
PHEN
.8
P3
PHEN
.3
P3
PHEN
.9
P3
PHEN
.10
P3
PHEN
.11
-----
rw -rw - - -rw rw rw rw rw rwrw -rw rw
P3
PHEN
.12
C165H
Parallel Ports
Data Sheet 147 2001-04-19
PRELIMINARY
- EXCERPT -
7.4.1 Alternate Functions of PORT3
The pins of Port 3 serve for various functions which include external timer control lines,
the two serial interfaces and the control lines BHE and CLKOUT.
Table 21 summarizes the alternate functions of Port 3.
Table 21 Alternate Functions of Port 3
Figure 34 Port 3 I/O and Alternate Functions
Port 3 Pin Alternate Function
P3.0
P3.1
P3.2
P3.3
P3.4
P3.5
P3.6
P3.7
P3.8
P3.9
P3.10
P3.11
P3.12
P3.13
P3.14
P3.15
--- No pin assigned
--- No pin assigned
--- No pin assigned
T3OUT Timer 3 Toggle Output
--- No pin assigned!
T4IN Timer 4 Count Input (T3EUD Input, T2EUD Input)
T3IN Timer 3 Count Input
T2IN Timer 2 Count Input
MRST SSC Master Receive / Slave Transmit
MTSR SSC Master Transmit / Slave Receive
TxD0 ASC Transmit Data Output
RxD0 ASC Receive Data Input
BHE/WRH Byte High Enable / Write High Output
SCLK SSC Shift Clock Input/Output
--- No pin assigned
CLKOUT System Clock Output
P3.15
P3.13
P3.12
P3.11
P3.10
P3.9
P3.8
P3.7
P3.6
P3.5
P3.3
Port 3
No Pin CLKOUT
SCLK
BHE
RxD0Tx
D0
MTSR
MRST
T2IN
T3IN
T4IN
T3OUT
WRH
Alternate Function a) b)
General Purpose
Input/Output
No Pin
No Pin
No Pin
No Pin
C165H
Parallel Ports
Data Sheet 148 2001-04-19
PRELIMINARY
- EXCERPT -
The port structure of the Port 3 pins depends on their alternate function (see figures
below).
When the on-chip peripheral associated with a Port 3 pin is configured to use the
alternate input function, it reads the input latch, which represents the state of the pin, via
the line labeled “Alternate Data Input”. Port 3 pins with alternate input functions are:
T2IN, T3IN and T4IN/T3EUD/T2EUD.
When the on-chip peripheral associated with a Port 3 pin is configured to use the
alternate output function, its “Alternate Data Output” line is ANDed with the port output
latch line. When using these alternate functions, the user must set the direction of the
port line to output (DP3.y=1) and must set the port output latch (P3.y=1). Otherwise the
pin is in its high-impedance state (when configured as input) or the pin is stuck at '0'
(when the port output latch is cleared). When the alternate output functions are not used,
the “Alternate Data Output” line is in its inactive state, which is a high level ('1'). Port 3
pins with alternate output functions are:
T6OUT, T3OUT, TxD0 and CLKOUT.
When the on-chip peripheral associated with a Port 3 pin is configured to use both the
alternate input and output function, the descriptions above apply to the respective
current operating mode. The direction must be set accordingly. Port 3 pins with alternate
input/output functions are:
MTSR, MRST, RxD0 and SCLK.
Note: Enabling the CLKOUT function automatically enables the P3.15 output driver.
Setting bit DP3.15=’1’ is not required.
C165H
Parallel Ports
Data Sheet 149 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 35 Block Diagram of a Port 3 Pin with Alternate Input or Alternate
Output Function (y = 13, 11...5, 3)
Pin P3.12 (BHE/WRH) is one more pin with an alternate output function. However, its
structure is slightly different (see figure below), because after reset the BHE or WRH
function must be used depending on the system startup configuration. In these cases
there is no possibility to program any port latches before. Thus the appropriate alternate
function is selected automatically. If BHE/WRH is not used in the system, this pin can be
used for general purpose I/O by disabling the alternate function (BYTDIS = ‘1’ /
WRCFG=’0’).
MCB02229
Output
Buffer
Alternate
Data
Latch
Port Output
0
1
MUX
Write P3.y
Read P3.y
Read DP3.y
Write DP3.y
Direction
Write ODP3.y
Read ODP3.y
Open Drain
Latch
Input
Latch
Clock
Latch
s
u
B
l
a
n
r
e
t
n
Ι
Input
&
Output
Data
Alternate
P3.y
y = 13, 11...5, 3
C165H
Parallel Ports
Data Sheet 150 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 36 Block Diagram of Pins P3.15 (CLKOUT) and P3.12 (BHE/WRH)
Note: Enabling the BHE or WRH function automatically enables the P3.12 output driver.
Setting bit DP3.12=’1’ is not required.
During bus hold pin P3.12 is switched back to its standard function and is then
controlled by DP3.12 and P3.12. Keep DP3.12 = ’0’ in this case to ensure floating
in hold mode.
7.5 PORT4
If this 7-bit port is used for general purpose I/O, the direction of each line can be
configured via the corresponding direction register DP4.
Each port line can be switched into push/pull or open drain mode via the open drain
control register ODP4.
For port pins configured as input (via DP4 or alternate function), an internal pull transistor
is connected to the pad if register P4PUDEN = ’1’, no matter wheter the C165H is in
normal operation mode or in power down mode. Either pulldown transistor or pullup
transistor will be selected via P4PUDSEL.
For port pins configured as output, the internal pull transistors are always disabled. The
output driver is disabled in power down mode unless P4PHEN = ’1’.
MCB02073
Output
Buffer
MUX
1
0
Alternate
Data
Output
Latch
Port Output
0
1
MUX
Write P3.x
Read P3.x
Enable
Function
Alternate
0
1
MUX
Read DP3.x
Write DP3.x
Direction
’1’
Input
Latch
Clock
Latch
Ι
n
t
e
r
n
a
l
B
u
s
P3.12/BHE
P3.15/CLKOUT
x = 15, 12
C165H
Parallel Ports
Data Sheet 151 2001-04-19
PRELIMINARY
- EXCERPT -
After reset, P4PUDEN and P4PUDSEL are set to LOW signal.
P4 (FFC8H / E4H) SFR Reset Value: - - 00H
DP4 (FFCAH / E5H) SFR Reset Value: - - 00H
ODP4 (F1CAH / E5H) ESFR Reset Value: - - 00H
Bit Function
P4.y Port data register P4 bit y
Bit Function
DP4.y Port direction register DP4 bit y
DP4.y = 0: Port line P4.y is an input (high-impedance)
DP4.y = 1: Port line P4.y is an output
Bit Function
ODP4.y Port 4 Open Drain control register bit y
ODP4.y = 0: Port line P4.y output driver in push/pull mode
ODP4.y = 1: Port line P4.y output driver in open drain mode
54321011 10 987615 14 13 12
rw rw rw rw rw rw-----rw----
P4.0P4.1P4.2P4.3P4.4P4.5P4.6
54321011 10 987615 14 13 12
rw rw rw rw rw rw-----rw----
DP4.0DP4.1DP4.2DP4.3DP4.4DP4.5DP4.6
54321011 10 987615 14 13 12
rw rw rw rw rw rw-----rw----
ODP2
.6 ODP2
.5 ODP2
.4 ODP2
.3 ODP2
.2 ODP2
.1 ODP2
.0
C165H
Parallel Ports
Data Sheet 152 2001-04-19
PRELIMINARY
- EXCERPT -
P4PUDSEL (FE84H / 42H) SFR Reset Value: - - 00H
P4PUDEN (FE86H / 43H) SFR Reset Value: - - 00H
P4PHEN (FE88H / 44H) SFR Reset Value: - - 00H
Bit Function
P4PUDSEL.y Pulldown/Pullup Selection
P4PUDSEL.y = 0: internal programmable pulldown transistor is selected
P4PUDSEL.y = 1: internal programmable pullup transistor is selected
Bit Function
P4PUDEN.y Pulldown/Pullup Enable
P4PUDEN.y = 0: internal programmable pull transistor is disabled
P4PUDEN.y = 1: internal programmable pull transistor is enabled
Bit Function
P4PHEN.y Output Driver Enable in Power Down Mode
P4PHEN.y = 0: output driver is disabled in power down mode
P4PHEN.y = 1: output driver is enabled in power down mode
54321011 10 987615 14 13 12
rw rw rw rw rw rw-----rw----
P4
PUD
SEL.6
P4
PUD
SEL.5
P4
PUD
SEL.4
P4
PUD
SEL.3
P4
PUD
SEL.2
P4
PUD
SEL.1
P4
PUD
SEL.0
54321011 10 987615 14 13 12
rw rw rw rw rw rw-----rw----
P4
PUD
EN.6
P4
PUD
EN.5
P4
PUD
EN.4
P4
PUD
EN.3
P4
PUD
EN.2
P4
PUD
EN.1
P4
PUD
EN.0
54321011 10 987615 14 13 12
rw rw rw rw rw rw-----rw----
P4
PHEN
.6
P4
PHEN
.5
P4
PHEN
.4
P4
PHEN
.3
P4
PHEN
.2
P4
PHEN
.1
P4
PHEN
.0
C165H
Parallel Ports
Data Sheet 153 2001-04-19
PRELIMINARY
- EXCERPT -
7.5.1 Alternate Functions of PORT4
During external bus cycles that use segmentation (ie. an address space above
64 KByte) a number of Port 4 pins may output the segment address lines. The number
of pins that is used for segment address output determines the external address space
which is directly accessible. The other pins of Port 4 (if any) may be used for general
purpose I/O. If segment address lines are selected, the alternate function of Port 4 may
be necessary to access eg. external memory directly after reset. For this reason Port 4
will be switched to its alternate function automatically.
The number of segment address lines is selected via PORT0 during reset. The selected
value can be read from bitfield SALSEL in register RP0H (read only) eg. in order to check
the configuration during run time.
Table 22 summarizes the alternate functions of Port 4 depending on the number of
selected segment address lines (coded via bitfield SALSEL).
Table 22 Alternate Functions of Port 4
Figure 37 Port 4 I/O and Alternate Functions
Port 4 Pin Std. Function
SALSEL=01 64 KB
Altern. Function
SALSEL=11256 KB
Altern. Function
SALSEL=00 1 MB
Altern. Function
SALSEL=10 8 MB
P4.0
P4.1
P4.2
P4.3
P4.4
P4.5
P4.6
Gen. purpose I/O
Gen. purpose I/O
Gen. purpose I/O
Gen. purpose I/O
Gen. purpose I/O
Gen. purpose I/O
Gen. purpose I/O
Seg. Address A16
Seg. Address A17
Gen. purpose I/O
Gen. purpose I/O
Gen. purpose I/O
Gen. purpose I/O
Gen. purpose I/O
Seg. Address A16
Seg. Address A17
Seg. Address A18
Seg. Address A19
Gen. purpose I/O
Gen. purpose I/O
Gen. purpose I/O
Seg. Address A16
Seg. Address A17
Seg. Address A18
Seg. Address A19
Seg. Address A20
Seg. Address A21
Seg. Address A22
-
-
-
-
-
-
-
-
-
P4.6
P4.5
P4.4
P4.3
P4.2
P4.1
P4.0
Port 4
-
-
-
-
-
-
-
-
-
A22
A21
A20
A19
A18
A17
A16
Alternate Function
General Purpose
Input/Output
C165H
Parallel Ports
Data Sheet 154 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 38 Block Diagram of a Port 4 Pin (y = 6...0)
7.6 PORT6
If this 8-bit port is used for general purpose I/O, the direction of each line can be
configured via the corresponding direction register DP6. Each port line can be switched
into push/pull or open drain mode via the open drain control register ODP6.
For port pins configured as input (via DP6 or alternate function), an internal pull transistor
is connected to the pad if register P6PUDEN = ’1’, no matter wheter the C165H is in
normal operation mode or in power down mode. Either pulldown transistor or pullup
transistor will be selected via P6PUDSEL.
For port pins configured as output, the internal pull transistors are always disabled. The
output driver is disabled in power down mode unless P6PHEN = ’1’.
After reset, P6PUDEN and P6PUDSEL are set to LOW signal.
MCB02075
Output
Buffer
MUX
1
0
Alternate
Data
Output
Latch
Port Output
0
1
MUX
Write P4.y
Read P4.y
Enable
Function
Alternate
0
1
MUX
Read DP4.y
Write DP4.y
Direction
’1’
Input
Latch
Clock
Latch
s
u
B
l
a
n
r
e
t
n
Ι
P4.y
C165H
Parallel Ports
Data Sheet 155 2001-04-19
PRELIMINARY
- EXCERPT -
P6 (FFCCH / E6H) SFR Reset Value: - - 00H
DP6 (FFCEH / E7H) SFR Reset Value: - - 00H
Bit Function
P6.y Port data register P6 bit y
Bit Function
DP6.y Port direction register DP6 bit y
DP6.y = 0: Port line P6.y is an input (high-impedance)
DP6.y = 1: Port line P6.y is an output
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
P6.0P6.1P6.2P6.3P6.4P6.5P6.6P6.7
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
DP6.0DP6.1DP6.2DP6.3DP6.4DP6.5DP6.6DP6.7
C165H
Parallel Ports
Data Sheet 156 2001-04-19
PRELIMINARY
- EXCERPT -
ODP6 (F1CEH / E7H) ESFR Reset Value: - - 00H
P6PUDSEL (FE90H / 48H) SFR Reset Value: - - 00H
P6PUDEN (FE92H / 49H) SFR Reset Value: - - 00H
Bit Function
ODP6.y Port 6 Open Drain control register bit y
ODP6.y = 0: Port line P6.y output driver in push/pull mode
ODP6.y = 1: Port line P6.y output driver in open drain mode
Bit Function
P6PUDSEL.y Pulldown/Pullup Selection
P6PUDSEL.y = 0: internal programmable pulldown transistor is selected
P6PUDSEL.y = 1: internal programmable pullup transistor is selected
Bit Function
P6PUDEN.y Pulldown/Pullup Enable
P6PUDEN.y = 0: internal programmable pull transistor is disabled
P6PUDEN.y = 1: internal programmable pull transistor is enabled
54321011 10 987615 14 13 12
rw rw rw rw rw rw- - - - rw rw----
ODP6
.7 ODP6
.6 ODP6
.5 ODP6
.4 ODP6
.3 ODP6
.2 ODP6
.1 ODP6
.0
54321011 10 987615 14 13 12
rw rw rw rw rw rw- - - - rw rw----
P6
PUD
SEL.7
P6
PUD
SEL.6
P6
PUD
SEL.5
P6
PUD
SEL.4
P6
PUD
SEL.3
P6
PUD
SEL.2
P6
PUD
SEL.1
P6
PUD
SEL.0
54321011 10 987615 14 13 12
rw rw rw rw rw rw- - - - rw rw----
P6
PUD
EN.7
P6
PUD
EN.6
P6
PUD
EN.5
P6
PUD
EN.4
P6
PUD
EN.3
P6
PUD
EN.2
P6
PUD
EN.1
P6
PUD
EN.0
C165H
Parallel Ports
Data Sheet 157 2001-04-19
PRELIMINARY
- EXCERPT -
P6PHEN (FE94H / 4AH) SFR Reset Value: - - 00H
7.6.1 Alternate Functions of PORT6
A programmable number of chip select signals (CS4...CS0) derived from the bus control
registers (BUSCON4...BUSCON0) can be output on 5 pins of Port 6. The other 3 pins
may be used for bus arbitration to accomodate additional masters in a C165H system.
The number of chip select signals is selected via PORT0 during reset. The selected
value can be read from bitfield CSSEL in register RP0H (read only) eg. in order to check
the configuration during run time.
Table 23 summarizes the alternate functions of Port 6 depending on the number of
selected chip select lines (coded via bitfield CSSEL).
Table 23 Alternate Functions of Port 6
Bit Function
P6PHEN.y Output Driver Enable in Power Down Mode
P6PHEN.y = 0: output driver is disabled in power down mode
P6PHEN.y = 1: output driver is enabled in power down mode
Port 6 Pin Altern. Function
CSSEL = 10
Altern. Function
CSSEL = 01
Altern. Function
CSSEL = 00
Altern. Function
CSSEL = 11
P6.0
P6.1
P6.2
P6.3
P6.4
Gen. purpose I/O
Gen. purpose I/O
Gen. purpose I/O
Gen. purpose I/O
Gen. purpose I/O
Chip select CS0
Chip select CS1
Gen. purpose I/O
Gen. purpose I/O
Gen. purpose I/O
Chip select CS0
Chip select CS1
Chip select CS2
Gen. purpose I/O
Gen. purpose I/O
Chip select CS0
Chip select CS1
Chip select CS2
Chip select CS3
Chip select CS4
P6.5
P6.6
P6.7
HOLD External hold request input
HLDA Hold acknowledge output
BREQ Bus request output
54321011 10 987615 14 13 12
rw rw rw rw rw rw----rw rw----
P6
PHEN
.7
P6
PHEN
.6
P6
PHEN
.5
P6
PHEN
.4
P6
PHEN
.3
P6
PHEN
.2
P6
PHEN
.1
P6
PHEN
.0
C165H
Parallel Ports
Data Sheet 158 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 39 Port 6 I/O and Alternate Functions
The chip select lines of Port 6 additionally have an internal weak pullup device. This
device is switched on under the following conditions:
• always during reset
• if the Port 6 line is used as a chip select output, and the C165H is in Hold mode
(invoked through HOLD), and the respective pin driver is in push/pull mode (ODP6.x
= ‘0’).
This feature is implemented to drive the chip select lines high during reset in order to
avoid multiple chip selection, and to allow another master to access the external memory
via the same chip select lines (Wired-AND), while the C165H is in Hold mode.
With ODP6.x = ‘1’ (open drain output selected), the internal pullup device will not be
active during Hold mode; external pullup devices must be used in this case.
When entering Hold mode the CS lines are actively driven high for one clock phase, then
the output level is controlled by the pullup devices (if activated).
After reset the CS function must be used, if selected so. In this case there is no possibility
to program any port latches before. Thus the alternate function (CS) is selected
automatically in this case.
Note: The open drain output option can only be selected via software earliest during the
initialization routine; at least signal CS0 will be in push/pull output driver mode
directly after reset.
-
-
-
-
-
-
-
-
P6.7
P6.6
P6.5
P6.4
P6.3
P6.2
P6.1
P6.0
Port 6
-
-
-
-
-
-
-
-
BREQ
HLDA
HOLD
CS4
CS3
CS2
CS1
CS0
Alternate Function a)
General Purpose
Input/Output
C165H
Parallel Ports
Data Sheet 159 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 40 Block Diagram of Port 6 Pins with an alternate output function
The bus arbitration signals HOLD, HLDA and BREQ are selected with bit HLDEN in
register PSW. When the bus arbitration signals are enabled via HLDEN, also these pins
are switched automatically to the appropriate direction. Note that the pin drivers for
HLDA and BREQ are automatically enabled, while the pin driver for HOLD is
automatically disabled.
MCB01982
Output
Buffer
MUX
1
0
Alternate
Data
Output
Latch
Port Output
0
1
MUX
Write P6.y
Read P6.y
Enable
Function
Alternate
0
1
MUX
Read DP6.y
Write DP6.y
Direction
Write ODP6.y
Read ODP6.y
Open Drain
Latch
’1’
Input
Latch
Clock
Latch
Ι
n
t
e
r
n
a
l
B
u
sP6.y
C165H
Parallel Ports
Data Sheet 160 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 41 Block Diagram of Pin P6.5 (HOLD)
7.7 PORT7
In the C165H Port 7 is an 6-bit general purpose I/O port. The direction of each line can
be configured via the corresponding direction register DP7. Each port line can be
switched into push/pull or open drain mode via the open drain control register ODP7.
Note: There are no alternate functions for Port 7.
For port pins configured as input via DP7, an internal pull transistor is connected to the
pad if register P7PUDEN = ’1’, no matter wheter the C165H is in normal operation mode
or in power down mode. Either pulldown transistor or pullup transistor will be selected
via P7PUDSEL.
MCB01983
Output
Buffer
Alternate
Data Input
Latch
Port Output
0
1
MUX
Write P6.y
Read P6.y
Read DP6.y
Write DP6.y
Direction
Write ODP6.y
Read ODP6.y
Open Drain
Latch
Input
Latch
Clock
Latch
s
u
B
l
a
n
r
e
t
n
Ι
P6.5/HOLD
C165H
Parallel Ports
Data Sheet 161 2001-04-19
PRELIMINARY
- EXCERPT -
For port pins configured as output, the internal pull transistors are always disabled. The
output driver is disabled in power down mode unless P7PHEN = ’1’.
After reset, P7PUDEN and P7PUDSEL are set to LOW signal.
P7 (FFD0H / E8H) SFR Reset Value: - - 00H
DP7 (FFD2H / E9H) SFR Reset Value: - - 00H
ODP7 (F1D2H / E9H) ESFR Reset Value: - - 00
Bit Function
P7.y Port data register P7 bit y
Bit Function
DP7.y Port direction register DP7 bit y
DP7.y = 0: Port line P7.y is an input (high-impedance)
DP7.y = 1: Port line P7.y is an output
Bit Function
ODP7.y Port 7 Open Drain control register bit y
ODP7.y = 0: Port line P7.y output driver in push/pull mode
ODP7.y = 1: Port line P7.y output driver in open drain mode
P7.0P7.1P7.2P7.4P7.5
54321011 10 987615 14 13 12
rw rw rw rw rw rw----------
P7.3
DP7.0DP7.1DP7.2DP7.4DP7.5
54321011 10 987615 14 13 12
rw rw rw rw rw rw----------
DP7.3
ODP7
.0
ODP7
.1
ODP7
.2
ODP7
.4
ODP7
.5
54321011 10 987615 14 13 12
rw rw rw rw rw rw----------
ODP7
.3
C165H
Parallel Ports
Data Sheet 162 2001-04-19
PRELIMINARY
- EXCERPT -
P7PUDSEL (FE96H / 4BH) SFR Reset Value: - - 00H
P7PUDEN (FE98H / 4CH) SFR Reset Value: - - 00H
P7PHEN (FE9AH / 4DH) SFR Reset Value: - - 00H
Bit Function
P7PUDSEL.y Pulldown/Pullup Selection
P7PUDSEL.y = 0: internal programmable pulldown transistor is selected
P7PUDSEL.y = 1: internal programmable pullup transistor is selected
Bit Function
P7PUDEN.y Pulldown/Pullup Enable
P7PUDEN.y = 0: internal programmable pull transistor is disabled
P7PUDEN.y = 1: internal programmable pull transistor is enabled
Bit Function
P7PHEN.y Output Driver Enable in Power Down Mode
P7PHEN.y = 0: output driver is disabled in power down mode
P7PHEN.y = 1: output driver is enabled in power down mode
54321011 10 987615 14 13 12
rw rw rw rw rw rw----------
P7
PUD
SEL.5
P7
PUD
SEL.4
P7
PUD
SEL.3
P7
PUD
SEL.2
P7
PUD
SEL.1
P7
PUD
SEL.0
54321011 10 987615 14 13 12
rw rw rw rw rw rw----------
P7
PUD
EN.5
P7
PUD
EN.4
P7
PUD
EN.3
P7
PUD
EN.2
P7
PUD
EN.1
P7
PUD
EN.0
54321011 10 987615 14 13 12
rw rw rw rw rw rw- - - - rw rw----
P6
PHEN
.5
P6
PHEN
.4
P6
PHEN
.3
P6
PHEN
.2
P6
PHEN
.1
P6
PHEN
.0
C165H
Dedicated Pins
Data Sheet 163 2001-04-19
PRELIMINARY
- EXCERPT -
8 Dedicated Pins
Most of the input/output or control signals of the functional the C165H are realized as
alternate functions of pins of the parallel ports. There is, however, a number of signals
that use separate pins, including the IOM-2 interface, the oscillator, special control
signals and the power supply. Table 24 summarizes all dedicated pins of the C165H.
Table 24 Dedicated Pins
The Address Latch Enable signal ALE controls external address latches that provide
a stable address in multiplexed bus modes.
ALE is activated for every external bus cycle independent of the selected bus mode, ie.
it is also activated for bus cycles with a demultiplexed address bus. When an external
bus is enabled (one or more of the BUSACT bits set) also X-Peripheral accesses will
generate an active ALE signal.
ALE is not activated for internal accesses, ie. the internal RAM and the special function
registers. In single chip mode, ie. when no external bus is enabled (no BUSACT bit set),
ALE will also remain inactive for X-Peripheral accesses.
External Read Strobe RD controls the output drivers of external memory or peripherals
when the C165H reads data from these external devices. During reset and during Hold
mode an internal pullup ensures an inactive (high) level on the RD output.
Pin(s) Function
ALE Address Latch Enable
RD External Read Strobe
WR/WRL External Write/Write Low Strobe
READY Ready Input
EA External Access Enable
NMI Non-Maskable Interrupt Input
RSTIN Reset Input
RSTOUT Reset Output
XTAL1, XTAL2 Oscillator Input/Output
CLKMODE Oscillator Clock Input Mode Select
DU, DD, DCL, FSC IOM-2
BRKIN, BRKOUT OCDS
TDI, TDO, TCK, TMS, TRST JTAG Interface
TEST Test Mode Enable
VDD, GND Power Supply and Ground (19 pins VDD, 19 pins GND)
C165H
Dedicated Pins
Data Sheet 164 2001-04-19
PRELIMINARY
- EXCERPT -
External Write Strobe WR/WRL controls the data transfer from the C165H to an
external memory or peripheral device. This pin may either provide an general WR signal
activated for both byte and word write accesses, or specifically control the low byte of an
external 16-bit device (WRL) together with the signal WRH (alternate function of P3.12/
BHE). During reset and during Hold mode an internal pullup ensures an inactive (high)
level on the WR/WRL output.
Note: Whether RD and WR/WRL remain idle during X-peripheral accesses depends on
the value of bit VISIBLE of register SYSCON.
Ready Input READY receives a control signal from an external memory or peripheral
device that is used to terminate an external bus cycle, provided that this function is
enabled for the current bus cycle. READY may be used as synchronous READY or may
be evaluated asynchronously. When waitstates are defined for a READY controlled
address window the READY input is not evaluated during these waitstates.
External Access Enable Pin EA is dedicated for on-chip ROM derivates. In this case it
determines, if the chip after reset starts fetching code from the internal ROM area
(EA=’1’) or via the external bus interface (EA=’0’). For the ROM-less C165H be sure to
hold this input low.
Non-Maskable Interrupt Input NMI allows to trigger a high priority trap via an external
signal (eg. a power-fail signal). It also serves to validate the PWRDN instruction that
switches the C165H into Power-Down mode. The NMI pin is sampled with every CPU
clock cycle to detect transitions.
Oscillator Input XTAL1 and Output XTAL2 connect the internal Pierce oscillator to the
external crystal. The oscillator provides an inverter and a feedback element. The
standard external oscillator circuitry (see figure below) comprises the crystal, two low
end capacitors and series resistor to limit the current through the crystal. The additional
LC combination is only required for 3rd overtone crystals to suppress oscillation in the
fundamental mode. A test resistor (RQ) may be temporarily inserted to measure the
oscillation allowance of the oscillator circuitry.
An external clock signal may be fed to the input XTAL1, leaving XTAL2 open.
Note: It is strongly recommended to measure the oscillation allowance (or margin) in the
final target system (layout) to determine the optimum parameters for the oscillator
operation.
The following starting configuration is recommended to be used for the C165H:
Quarz: CL = 30 pF (max.), RS = 70 Ohm (max.), Accuracy: 96 ppm or better
External: Circuitry: CA = CB = 47 pF (max.), no serial resistor (Rx2 = 0)
C165H
Dedicated Pins
Data Sheet 165 2001-04-19
PRELIMINARY
- EXCERPT -
Note: Please check the Infineon Application Notes in addition to this recommendation.
Figure 42 External Oscillator Circuitry
The Clock Mode Select CLKMODE CLKMODE must be LOW if an external crystal is
used. HIGH signal enables the direct clock input path and switches the internal oscillator
in power down mode..
The Reset Input RSTIN allows to put the C165H into the well defined reset condition
either at power-up or external events like a hardware failure or manual reset. The input
voltage threshold of the RSTIN pin is raised compared to the standard pins in order to
minimize the noise sensitivity of the reset input.
The Reset Output RSTOUT provides a special reset signal for external circuitry.
RSTOUT is activated at the beginning of the reset sequence, triggered via RSTIN, a
watchdog timer overflow or by the SRST instruction. RSTOUT remains active (low) until
the EINIT instruction is executed. This allows to initialize the controller before the
external circuitry is activated.
The Power Supply pins VDD and GND provide the power supply for the digital logic of
the C165H. The respective VCC/VSS pairs should be decoupled as close to the pins as
possible. For best results it is recommended to implement two-level decoupling, eg. (the
widely used) 100 nF in parallel with 30...40 pF capacitors which deliver the peak
currents.
Note: All VDD pins and all GND pins must be connected to the power supply and ground,
respectively.
XTAL1 XTAL2
Rx2RQ
CACB
C165H
External Bus Interface
Data Sheet 166 2001-04-19
PRELIMINARY
- EXCERPT -
9 External Bus Interface
Although the C165H provides a powerful set of on-chip peripherals and on-chip RAM
areas, these internal units only cover a small fraction of its address space of up to 8
MByte. The external bus interface allows to access external peripherals and additional
volatile and non-volatile memory. The external bus interface provides a number of
configurations, so it can be taylored to fit perfectly into a given application system.
Figure 43 SFRs and Port Pins Associated with the External Bus Interface
Accesses to external memory or peripherals are executed by the integrated External Bus
Controller (EBC). The function of the EBC is controlled via the SYSCON register and the
BUSCONx and ADDRSELx registers. The BUSCONx registers specify the external bus
cycles in terms of address (mux/demux), data (16-bit/8-bit), chip selects and length
(waitstates / READY control / ALE / RW delay). These parameters are used for accesses
within a specific address area which is defined via the corresponding register
ADDRSELx.
The four pairs BUSCON1/ADDRSEL1...BUSCON4/ADDRSEL4 allow to define four
independent “address windows”, while all external accesses outside these windows are
controlled via register BUSCON0.
P4
BUSCON0
BUSCON1
BUSCON2
ADDRSEL4
P0L / P0H
P6
ADDRSEL1
ODP6
P0L/P0H PORT0 Data Registers
P1L/P1H PORT1 Data Registers
DP3 Port 3 Direction Control Register
P3 Port 3 Data Register
P4 Port 4 Data Register
ODP6 Port 6 Open Drain Control Register
DP6 Port 6 Direction Control Register
P6 Port 6 Data Register
PORT0 EA
PORT1 RSTIN
ALE READY
RD
WR/WRL
BHE/WRH
SYSCON
Control Registers
ADDRSELx Address Range Select Register 1...4
BUSCONx Bus Mode Control Register 0...4
SYSCON System Control Register
RP0H Port P0H Reset Configuration Register
Ports & Direction Control
Alternate Functions
Address Registers Mode Registers Control Registers
BUSCON3
P1L / P1H
BUSCON4
ADDRSEL2
RP0H
DP6
DP3
P3 ADDRSEL3
C165H
External Bus Interface
Data Sheet 167 2001-04-19
PRELIMINARY
- EXCERPT -
Single Chip Mode
Single chip mode is entered, when pin EA is high during reset. In this case register
BUSCON0 is initialized with 0000H, which also resets bit BUSACT0, so no external bus
is enabled.
In single chip mode the C165H operates only with and out of internal resources. No
external bus is configured and no external peripherals and/or memory can be accessed.
Also no port lines are occupied for the bus interface. When running in single chip mode,
however, external access may be enabled by configuring an external bus under software
control.
Note: Any attempt to access a location in the external memory space in single chip mode
results in the hardware trap ILLBUS.
9.1 External Bus Modes
When the external bus interface is enabled (bit BUSACTx=’1’) and configured (bitfield
BTYP), the C165H uses a subset of its port lines together with some control lines to build
the external bus.
The bus configuration (BTYP) for the address windows (BUSCON4...BUSCON1) is
selected via software typically during the initialization of the system.
The bus configuration (BTYP) for the default address range (BUSCON0) is selected via
PORT0 during reset, provided that pin EA is low during reset. Otherwise BUSCON0 may
be programmed via software just like the other BUSCON registers.
The 16 MByte address space of the C165H is divided into 256 segments of 64 KByte
each. The 16-bit intra-segment address is output on PORT0 for multiplexed bus modes
or on PORT1 for demultiplexed bus modes. When segmentation is disabled, only one 64
KByte segment can be used and accessed. Otherwise additional address lines may be
output on Port 4, and/or several chip select lines may be used to select different memory
banks or peripherals. These functions are selected during reset via bitfields SALSEL and
CSSEL of register RP0H, respectively.
Note: Bit SGTDIS of register SYSCON defines, if the CSP register is saved during
interrupt entry (segmentation active) or not (segmentation disabled).
BTYP Encoding External Data Bus Width External Address Bus Mode
0 0 8-bit Data Demultiplexed Addresses
0 1 8-bit Data Multiplexed Addresses
1 0 16-bit Data Demultiplexed Addresses
1 1 16-bit Data Multiplexed Addresses
C165H
External Bus Interface
Data Sheet 168 2001-04-19
PRELIMINARY
- EXCERPT -
Multiplexed Bus Modes
In the multiplexed bus modes the 16-bit intra-segment address as well as the data use
PORT0. The address is time-multiplexed with the data and has to be latched externally.
The width of the required latch depends on the selected data bus width, ie. an 8-bit data
bus requires a byte latch (the address bits A15...A8 on P0H do not change, while P0L
multiplexes address and data), a 16-bit data bus requires a word latch (the least
significant address line A0 is not relevant for word accesses).
The upper address lines (An...A16) are permanently output on Port 4 (if segmentation is
enabled) and do not require latches.
The EBC initiates an external access by generating the Address Latch Enable signal
(ALE) and then placing an address on the bus. The falling edge of ALE triggers an
external latch to capture the address. After a period of time during which the address
must have been latched externally, the address is removed from the bus. The EBC now
activates the respective command signal (RD, WR, WRL, WRH). Data is driven onto the
bus either by the EBC (for write cycles) or by the external memory/peripheral (for read
cycles). After a period of time, which is determined by the access time of the memory/
peripheral, data become valid.
Read cycles: Input data is latched and the command signal is now deactivated. This
causes the accessed device to remove its data from the bus which is then tri-stated
again.
Write cycles: The command signal is now deactivated. The data remain valid on the bus
until the next external bus cycle is started.
C165H
External Bus Interface
Data Sheet 169 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 44 Multiplexed Bus Cycle
Demultiplexed Bus Modes
In the demultiplexed bus modes the 16-bit intra-segment address is permanently output
on PORT1, while the data uses PORT0 (16-bit data) or P0L (8-bit data).
The upper address lines are permanently output on Port 4 (if selected via SALSEL during
reset). No address latches are required.
The EBC initiates an external access by placing an address on the address bus. After a
programmable period of time the EBC activates the respective command signal (RD,
WR, WRL, WRH). Data is driven onto the data bus either by the EBC (for write cycles)
or by the external memory/peripheral (for read cycles). After a period of time, which is
determined by the access time of the memory/peripheral, data become valid.
Read cycles: Input data is latched and the command signal is now deactivated. This
causes the accessed device to remove its data from the data bus which is then tri-stated
again.
Write cycles: The command signal is now deactivated. If a subsequent external bus
cycle is required, the EBC places the respective address on the address bus. The data
remain valid on the bus until the next external bus cycle is started.
MCT02060
Address
Segment (P4)
ALE
BUS (P0) Data/Instr.
Address
RD
Address Data
BUS (P0)
WR
Bus Cycle
C165H
External Bus Interface
Data Sheet 170 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 45 Demultiplexed Bus Cycle
Switching between the Bus Modes
The EBC allows to switch between different bus modes dynamically, ie. subsequent
external bus cycles may be executed in different ways. Certain address areas may use
multiplexed or demultiplexed buses or use READY control or predefined waitstates.
A change of the external bus characteristics can be initiated in two different ways:
Reprogramming the BUSCON and/or ADDRSEL registers allows to either change
the bus mode for a given address window, or change the size of an address window that
uses a certain bus mode. Reprogramming allows to use a great number of different
address windows (more than BUSCONs are available) on the expense of the overhead
for changing the registers and keeping appropriate tables.
Switching between predefined address windows automatically selects the bus mode
that is associated with the respective window. Predefined address windows allow to use
different bus modes without any overhead, but restrict their number to the number of
BUSCONs. However, as BUSCON0 controls all address areas, which are not covered
by the other BUSCONs, this allows to have gaps between these windows, which use the
bus mode of BUSCON0.
PORT1 will output the intra-segment address, when any of the BUSCON registers
selects a demultiplexed bus mode, even if the current bus cycle uses a multiplexed bus
mode. This allows to have an external address decoder connected to PORT1 only, while
using it for all kinds of bus cycles.
MCD02061
Address
Address (P1)
ALE
BUS (P0)
RD
Data
BUS (P0)
WR
Segment (P4)
Bus Cycle
Data/Instr.
C165H
External Bus Interface
Data Sheet 171 2001-04-19
PRELIMINARY
- EXCERPT -
Note: Never change the configuration for an address area that currently supplies the
instruction stream. Due to the internal pipelining it is very difficult to determine the
first instruction fetch that will use the new configuration. Only change the
configuration for address areas that are not currently accessed. This applies to
BUSCON registers as well as to ADDRSEL registers.
The usage of the BUSCON/ADDRSEL registers is controlled via the issued addresses.
When an access (code fetch or data) is initiated, the respective generated physical
address defines, if the access is made internally, uses one of the address windows
defined by ADDRSEL4...1, or uses the default configuration in BUSCON0. After
initializing the active registers, they are selected and evaluated automatically by
interpreting the physical address. No additional switching or selecting is necessary
during run time, except when more than the four address windows plus the default is to
be used.
Switching from demultiplexed to multiplexed bus mode represents a special case.
The bus cycle is started by activating ALE and driving the address to Port 4 and PORT1
as usual, if another BUSCON register selects a demultiplexed bus. However, in the
multiplexed bus modes the address is also required on PORT0. In this special case the
address on PORT0 is delayed by one CPU clock cycle, which delays the complete
(multiplexed) bus cycle and extends the corresponding ALE signal (see figure below).
This extra time is required to allow the previously selected device (via demultiplexed bus)
to release the data bus, which would be available in a demultiplexed bus cycle.
C165H
External Bus Interface
Data Sheet 172 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 46 Switching from Demultiplexed to Multiplexed Bus Mode
External Data Bus Width
The EBC can operate on 8-bit or 16-bit wide external memory/peripherals. A 16-bit data
bus uses PORT0, while an 8-bit data bus only uses P0L, the lower byte of PORT0. This
saves on address latches, bus transceivers, bus routing and memory cost on the
expense of transfer time. The EBC can control word accesses on an 8-bit data bus as
well as byte accesses on a 16-bit data bus.
Word accesses on an 8-bit data bus are automatically split into two subsequent byte
accesses, where the low byte is accessed first, then the high byte. The assembly of bytes
to words and the disassembly of words into bytes is handled by the EBC and is
transparent to the CPU and the programmer.
Byte accesses on a 16-bit data bus require that the upper and lower half of the memory
can be accessed individually. In this case the upper byte is selected with the BHE signal,
while the lower byte is selected with the A0 signal. So the two bytes of the memory can
be enabled independent from each other, or together when accessing words.
When writing bytes to an external 16-bit device, which has a single CS input, but two WR
enable inputs (for the two bytes), the EBC can directly generate these two write control
signals. This saves the external combination of the WR signal with A0 or BHE. In this
case pin WR serves as WRL (write low byte) and pin BHE serves as WRH (write high
MCD02234
Address
Data/Instr.
Address
Address Data
Bus Cycle
Address
Address (P1)
ALE
RD
Data
WR
Segment (P4)
Bus Cycle
BUS (P0)
BUS (P0)
Demultiplexed Multiplexed
Idle State
Data/Instr.
C165H
External Bus Interface
Data Sheet 173 2001-04-19
PRELIMINARY
- EXCERPT -
byte). Bit WRCFG in register SYSCON selects the operating mode for pins WR and
BHE. The respective byte will be written on both data bus halfs.
When reading bytes from an external 16-bit device, whole words may be read and the
C165H automatically selects the byte to be input and discards the other. However, care
must be taken when reading devices that change state when being read, like FIFOs,
interrupt status registers, etc. In this case individual bytes should be selected using BHE
and A0.
Note: PORT1 gets available for general purpose I/O, when none of the BUSCON
registers selects a demultiplexed bus mode.
Disable/Enable Control for Pin BHE (BYTDIS)
Bit BYTDIS is provided for controlling the active low Byte High Enable (BHE) pin. The
function of the BHE pin is enabled, if the BYTDIS bit contains a '0'. Otherwise, it is
disabled and the pin can be used as standard I/O pin. The BHE pin is implicitly used by
the External Bus Controller to select one of two byte-organized memory chips, which are
connected to the C165H via a word-wide external data bus. After reset the BHE function
is automatically enabled (BYTDIS = '0'), if a 16-bit data bus is selected during reset,
otherwise it is disabled (BYTDIS=’1’). It may be disabled, if byte access to 16-bit memory
is not required, and the BHE signal is not used.
Segment Address Generation
During external accesses the EBC generates a (programmable) number of address lines
on Port 4, which extend the 16-bit address output on PORT0 or PORT1, and so increase
the accessible address space. The number of segment address lines is selected during
reset and coded in bit field SALSEL in register RP0H (see table below).
Bus Mode Transfer Rate (Speed factor
for byte/word/dword access)
System Requirements Free I/O
Lines
8-bit Multiplexed Very low ( 1.5 / 3 / 6 ) Low (8-bit latch, byte bus) P1H, P1L
8-bit Demultipl. Low ( 1 / 2 / 4 ) Very low (no latch, byte bus) P0H
16-bit Multiplexed High ( 1.5 / 1.5 / 3 ) High (16-bit latch, word bus) P1H, P1L
16-bit Demultipl. Very high ( 1 / 1 / 2 ) Low (no latch, word bus) ---
SALSEL Segment Address Lines Directly accessible Address Space
1 1 Two: A17...A16 256 KByte (Default without pull-downs)
1 0 Seven: A22...A16 8 MByte (Maximum)
0 1 None 64 KByte (Minimum)
0 0 Four: A19...A16 1 MByte
C165H
External Bus Interface
Data Sheet 174 2001-04-19
PRELIMINARY
- EXCERPT -
Note: The total accessible address space may be increased by accessing several banks
which are distinguished by individual chip select signals.
CS Signal Generation
During external accesses the EBC can generate a (programmable) number of CS lines
on Port 6, which allow to directly select external peripherals or memory banks without
requiring an external decoder. The number of CS lines is selected during reset and
coded in bit field CSSEL in register RP0H (see table below).
The CSx outputs are associated with the BUSCONx registers and are driven active (low)
for any access within the address area defined for the respective BUSCON register. For
any access outside this defined address area the respective CSx signal will go inactive
(high). At the beginning of each external bus cycle the corresponding valid CS signal is
determined and activated. All other CS lines are deactivated (driven high) at the same
time.
Note: The CSx signals will not be updated for an access to any internal address area (ie.
when no external bus cycle is started), even if this area is covered by the
respective ADDRSELx register. An access to an on-chip X-Peripheral deactivates
all external CS signals.
Upon accesses to address windows without a selected CS line all selected CS
lines are deactivated.
The chip select signals allow to be operated in four different modes, which are selected
via bits CSWENx and CSRENx in the respective BUSCONx register.
Address Chip Select signals remain active until an access to another address window.
An address chip select becomes active with the falling edge of ALE and becomes
inactive with the falling edge of ALE of an external bus cycle that accesses a different
address area. No spikes will be generated on the chip select lines.
CSSEL Chip Select Lines Note
1 1 Five: CS4...CS0 Default without pull-downs
1 0 None Port 6 pins free for I/O
0 1 Two: CS1...CS0
0 0 Three: CS2...CS0
CSWENx CSRENx Chip Select Mode
0 0 Address Chip Select (Default after Reset, mode for CS0)
0 1 Read Chip Select
1 0 Write Chip Select
1 1 Read/Write Chip Select
C165H
External Bus Interface
Data Sheet 175 2001-04-19
PRELIMINARY
- EXCERPT -
Read or Write Chip Select signals remain active only as long as the associated control
signal (RD or WR) is active. This also includes the programmable read/write delay. Read
chip select is only activated for read cycles, write chip select is only activated for write
cycles, read/write chip select is activated for both read and write cycles (write cycles are
assumed, if any of the signals WRH or WRL gets active). These modes save external
glue logic, when accessing external devices like latches or drivers that only provide a
single enable input.
Note: CS0 provides an address chip select directly after reset (except for single chip
mode) when the first instruction is fetched.
Internal pullup devices hold all CS lines high during reset. After the end of a reset
sequence the pullup devices are switched off and the pin drivers control the pin levels
on the selected CS lines. Not selected CS lines will enter the high-impedance state and
are available for general purpose I/O.
The pullup devices are also active during bus hold on the selected CS lines, while HLDA
is active and the respective pin is switched to push/pull mode. Open drain outputs will
float during bus hold. In this case external pullup devices are required or the new bus
master is responsible for driving appropriate levels on the CS lines.
Segment Address versus Chip Select
The external bus interface of the C165H supports many configurations for the external
memory. By increasing the number of segment address lines the C165H can address a
linear address space of 256 KByte, 1 MByte or 8 MByte. This allows to implement a large
sequential memory area, and also allows to access a great number of external devices,
using an external decoder. By increasing the number of CS lines the C165H can access
memory banks or peripherals without external glue logic. These two features may be
combined to optimize the overall system performance. Enabling 4 segment address lines
and 5 chip select lines eg. allows to access five memory banks of 8 MByte each. So the
available address space is 40 MByte (without glue logic).
Note: Bit SGTDIS of register SYSCON defines, if the CSP register is saved during
interrupt entry (segmentation active) or not (segmentation disabled).
9.2 Programmable Bus Characteristics
Important timing characteristics of the external bus interface have been made user
programmable to allow to adapt it to a wide range of different external bus and memory
configurations with different types of memories and/or peripherals.
The following parameters of an external bus cycle are programmable:
• ALE Control defines the ALE signal length and the address hold time after its falling edge
• Memory Cycle Time (extendable with 1...15 waitstates) defines the allowable access time
• Memory Tri-State Time (extendable with 1 waitstate) defines the time for a data driver to float
C165H
External Bus Interface
Data Sheet 176 2001-04-19
PRELIMINARY
- EXCERPT -
• Read/Write Delay Time defines when a command is activated after the falling edge of ALE
• READY Control defines, if a bus cycle is terminated internally or externally
Note: Internal accesses are executed with maximum speed and therefore are not
programmable.
External acceses use the slowest possible bus cycle after reset. The bus cycle
timing may then be optimized by the initialization software.
Figure 47 Programmable External Bus Cycle
ALE Length Control
The length of the ALE signal and the address hold time after its falling edge are
controlled by the ALECTLx bits in the BUSCON registers. When bit ALECTL is set to ‘1’,
external bus cycles accessing the respective address window will have their ALE signal
prolonged by half a CPU clock. Also the address hold time after the falling edge of ALE
(on a multiplexed bus) will be prolonged by half a CPU clock, so the data transfer within
RD/WR
DATA
ADDR
ALE
ALECTL
DATA
RD/WR
ADDR
ALE
MTTCMCTC
MCD02225
C165H
External Bus Interface
Data Sheet 177 2001-04-19
PRELIMINARY
- EXCERPT -
a bus cycle refers to the same CLKOUT edges as usual (ie. the data transfer is delayed
by one CPU clock). This allows more time for the address to be latched.
Note: ALECTL0 is ‘1’ after reset to select the slowest possible bus cycle, the other
ALECTLx are ‘0’ after reset.
Figure 48 ALE Length Control
Programmable Memory Cycle Time
The C165H allows the user to adjust the controller's external bus cycles to the access
time of the respective memory or peripheral. This access time is the total time required
to move the data to the destination. It represents the period of time during which the
controller’s signals do not change.
Setup
(P0)
WR
BUS Address Data
(P0)BUS
RD
(P4)
ALE
Segment
Normal Multiplexed
Bus Cycle
Address
Address
Data/Instr.
Address Data
MCD02235
Lengthened Multiplexed
Bus Cycle
Address
Address
Hold
Data/Instr.
C165H
External Bus Interface
Data Sheet 178 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 49 Memory Cycle Time
The external bus cycles of the C165H can be extended for a memory or peripheral, which
cannot keep pace with the controller’s maximum speed, by introducing wait states during
the access (see figure above). During these memory cycle time wait states, the CPU is
idle, if this access is required for the execution of the current instruction.
The memory cycle time wait states can be programmed in increments of one CPU clock
within a range from 0 to 15 (default after reset) via the MCTC fields of the BUSCON
registers. 15-<MCTC> waitstates will be inserted.
Programmable Memory Tri-State Time
The C165H allows the user to adjust the time between two subsequent external
accesses to account for the tri-state time of the external device. The tri-state time defines,
when the external device has released the bus after deactivation of the read command
(RD).
MCT02063
Address
Segment
ALE
BUS (P0) Address
RD
Address Data
BUS (P0)
WR
MCTC Wait States (1...15)
Bus Cycle
Data/Instr.
C165H
External Bus Interface
Data Sheet 179 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 50 Memory Tri-State Time
The output of the next address on the external bus can be delayed for a memory or
peripheral, which needs more time to switch off its bus drivers, by introducing a wait state
after the previous bus cycle (see figure above). During this memory tri-state time wait
state, the CPU is not idle, so CPU operations will only be slowed down if a subsequent
external instruction or data fetch operation is required during the next instruction cycle.
The memory tri-state time waitstate requires one CPU clock (28 ns at fCPU = 36 MHz)
and is controlled via the MTTCx bits of the BUSCON registers. A waitstate will be
inserted, if bit MTTCx is ‘0’ (default after reset).
Note: External bus cycles in multiplexed bus modes implicitly add one tri-state time
waitstate in addition to the programmable MTTC waitstate.
Read/Write Signal Delay
The C165H allows the user to adjust the timing of the read and write commands to
account for timing requirements of external peripherals. The read/write delay controls the
time between the falling edge of ALE and the falling edge of the command. Without read/
write delay the falling edges of ALE and command(s) are coincident (except for
propagation delays). With the delay enabled, the command(s) become active half a CPU
clock after the falling edge of ALE.
The read/write delay does not extend the memory cycle time, and does not slow down
the controller in general. In multiplexed bus modes, however, the data drivers of an
external device may conflict with the C165H’s address, when the early RD signal is used.
Therefore multiplexed bus cycles should always be programmed with read/write delay.
MCT02065
Segment
ALE
BUS (P0) Address
RD
MTTC Wait State
Address
Bus Cycle
Data/Instr.
C165H
External Bus Interface
Data Sheet 180 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 51 Read/Write Delay
The read/write delay is controlled via the RWDCx bits in the BUSCON registers. The
command(s) will be delayed, if bit RWDCx is ‘0’ (default after reset).
Early WR Signal Deactivation
The duration of an external write access can be shortened by one TCL. The WR signal
is activated (driven low) in the standard way, but can be deactivated (driven high) one
TCL earlier than defined in the standard timing. In this case, also the data output drivers
will be deactivated one TCL earlier.
This is especially useful in systems which operate on higher CPU clock frequencies and
employ external modules (memories, peripherals, etc.) which switch on their own data
drivers very fast in response to e.g. a chip select signal.
Conflicts between the C165H and the external peripheral’s output drivers can be avoided
then by selecting early WR for the C165H.
Note: Make sure that the reduced WR low time then still matches the requirements of
the external peripheral/memory.
MCT02066
Address
Segment
ALE
BUS (P0)
1)
RD
Address Data
BUS (P0)
WR
Read/Write
Delay
Bus Cycle
Data/Instr.
The Data drivers from the previous bus cycle should be disabled when the RD signal becomes active.
1)
C165H
External Bus Interface
Data Sheet 181 2001-04-19
PRELIMINARY
- EXCERPT -
Early WR deactivation is controlled via the EWENx bits in the BUSCON registers (see
page 184). The WR signal will be shortened if bit EWENx is set to ’1’ signal. Default after
reset is a standard WR signal (EWENx = ’0’).
9.3 READY Controlled Bus Cycles
For situations, where the programmable waitstates are not enough, or where the
response (access) time of a peripheral is not constant, the C165H provides external bus
cycles that are terminated via a READY input signal (synchronous or asynchronous). In
this case the C165H first inserts a programmable number of waitstates (0...7) and then
monitors the READY line to determine the actual end of the current bus cycle. The
external device drives READY low in order to indicate that data have been latched (write
cycle) or are available (read cycle).
Figure 52 READY Controlled Bus Cycles
The READY function is enabled via the RDYENx bits in the BUSCON registers. When
this function is selected (RDYENx = ‘1’), only the lower 3 bits of the respective MCTC bit
field define the number of inserted waitstates (0...7), while the MSB of bit field MCTC
selects the READY operation:
MCTC.3 = ‘0’: Synchronous READY, ie. the READY signal must meet setup and hold times.
MCTC.3 = ‘1’: Asynchronous READY, ie. the READY signal is synchronized internally.
Evaluation (sampling) of the READY input
AREADY
SREADY
:
RD/WR
ALE
2. WS
with active READY
1. WS
Bus Cycle
MCD02237
extended via READY
1. WS 2. WS
Bus Cycle
C165H
External Bus Interface
Data Sheet 182 2001-04-19
PRELIMINARY
- EXCERPT -
Synchronous READY provides the fastest bus cycles, but requires setup and hold
times to be met. The CLKOUT signal should be enabled and may be used by the
peripheral logic to control the READY timing in this case.
Asynchronous READY is less restrictive, but requires additional waitstates caused by
the internal synchronization. As the asynchronous READY is sampled earlier (see figure
above) programmed waitstates may be necessary to provide proper bus cycles (see also
notes on “normally-ready” peripherals below).
A READY signal (especially asynchronous READY) that has been activated by an
external device may be deactivated in response to the trailing (rising) edge of the
respective command (RD or WR).
Note: When the READY function is enabled for a specific address window, each bus
cycle within this window must be terminated with an active READY signal.
Otherwise the controller hangs until the next reset. A timeout function is only
provided by the watchdog timer.
Combining the READY function with predefined waitstates is advantageous in two
cases:
Memory components with a fixed access time and peripherals operating with READY
may be grouped into the same address window. The (external) waitstate control logic in
this case would activate READY either upon the memory’s chip select or with the
peripheral’s READY output. After the predefined number of waitstates the C165H will
check its READY line to determine the end of the bus cycle. For a memory access it will
be low already (see example a) in the figure above), for a peripheral access it may be
delayed (see example b) in the figure above). As memories tend to be faster than
peripherals, there should be no impact on system performance.
When using the READY function with so-called “normally-ready” peripherals, it may lead
to erroneous bus cycles, if the READY line is sampled too early. These peripherals pull
their READY output low, while they are idle. When they are accessed, they deactivate
READY until the bus cycle is complete, then drive it low again. If, however, the peripheral
deactivates READY after the first sample point of the C165H, the controller samples an
active READY and terminates the current bus cycle, which, of course, is too early. By
inserting predefined waitstates the first READY sample point can be shifted to a time,
where the peripheral has safely controlled the READY line (eg. after 2 waitstates in the
figure above).
C165H
External Bus Interface
Data Sheet 183 2001-04-19
PRELIMINARY
- EXCERPT -
9.4 Controlling the External Bus Controller
A set of registers controls the functions of the EBC. General features like the usage of
interface pins (WR, BHE), segmentation are controlled via register SYSCON.
Note: For SYSCON register description, refer to page 66.
The properties of a bus cycle like chip select mode, usage of READY, length of ALE,
external bus mode, read/write delay and waitstates are controlled via registers
BUSCON4...BUSCON0. Four of these registers (BUSCON4...BUSCON1) have an
address select register (ADDRSEL4...ADDRSEL1) associated with them, which allows
to specify up to four address areas and the individual bus characteristics within these
areas. All accesses that are not covered by these four areas are then controlled via
BUSCON0. This allows to use memory components or peripherals with different
interfaces within the same system, while optimizing accesses to each of them.
The layout of the five BUSCON registers is identical. Registers BUSCON4...BUSCON1,
which control the selected address windows, are completely under software control,
while register BUSCON0, which eg. is also used for the very first code access after reset,
is partly controlled by hardware, ie. it is initialized via PORT0 during the reset sequence.
This hardware control allows to define an appropriate external bus for systems, where
no internal program memory is provided.
C165H
External Bus Interface
Data Sheet 184 2001-04-19
PRELIMINARY
- EXCERPT -
BUSCON0 (FF0CH / 86H) SFR Reset Value: 0000H
BUSCON1 (FF14H / 8AH) SFR Reset Value: 0000H
BUSCON2 (FF16H / 8BH) SFR Reset Value: 0000H
BUSCON3 (FF18H / 8CH) SFR Reset Value: 0000H
BUSCON4 (FF1AH / 8DH) SFR Reset Value: 0000H
Note: BUSCON0 is initialized with 0000H, if pin EA is high during reset. If pin EA is low
Bit Function
MCTCx Memory Cycle Time Control (Number of memory cycle time wait states)
’0000’ : 15 waitstates (Number = 15 - <MCTC>)
. . .
’1111’ : No waitstates
RWDCx Read/Write Delay Control for BUSCONx
‘0’: With read/write delay: activate command 1 TCL after falling edge of ALE
‘1’: No read/write delay: activate command with falling edge of ALE
-
CSW
EN0 CSR
EN0 MTT
C0 RWD
C0
RDY
EN0
54321011 10 987615 14 13 12
rw rwrw rw rwrw rwrw - -
-BUS
ACT0
rw
ALE
CTL0
rw rw
BTYP MCTC
EW
EN0
-- MTT
C1 RWD
C1
RDY
EN1
54321011 10 987615 14 13 12
rw rwrw rw rwrw rw
BTYP MCTC
rw - -
BUS
ACT1
rw
ALE
CTL1
rw rw
CSW
EN1 CSR
EN1 EW
EN1
-- MTT
C2 RWD
C2
RDY
EN2
54321011 10 987615 14 13 12
rw rwrw rw rwrw rw
BTYP MCTC
rw - -
BUS
ACT2
rw
ALE
CTL2
rw rw
CSW
EN2 CSR
EN2 EW
EN2
-- MTT
C3 RWD
C3
RDY
EN3
54321011 10 987615 14 13 12
rw rwrw rw rwrw rw
BTYP MCTC
rw - -
BUS
ACT3
rw
ALE
CTL3
rw rw
CSW
EN3 CSR
EN3 EW
EN3
-- MTT
C4 RWD
C4
RDY
EN4
54321011 10 987615 14 13 12
rw rwrw rw rwrw rw
BTYP MCTC
rw - -
BUS
ACT4
rw
ALE
CTL4
rw rw
CSW
EN4 CSR
EN4 EW
EN4
C165H
External Bus Interface
Data Sheet 185 2001-04-19
PRELIMINARY
- EXCERPT -
during reset, bits BUSACT0 and ALECTL0 are set (‘1’) and bit field BTYP is loaded
with the bus configuration selected via PORT0.
MTTCx Memory Tristate Time Control
‘0’: 1 waitstate
‘1’: No waitstate
EWENx Early Write Enable Bit
‘0’: Normal write
‘1’: Early write is enabled. The write signal turns off one TCL earlier.
Note: In order to have no overlapping with the following ALE signal, the write
control signal is shortened by one TCL by setting bit EWEN.
BTYPx External Bus Configuration
0 0 : 8-bit Demultiplexed Bus
0 1 : 8-bit Multiplexed Bus
1 0 : 16-bit Demultiplexed Bus
1 1 : 16-bit Multiplexed Bus
Note: For BUSCON0 BTYP is defined via PORT0 during reset.
ALECTLx ALE Lengthening Control
‘0’: Normal ALE signal
‘1’: Lengthened ALE signal
BUSACTx Bus Active Control
‘0’: External bus disabled
‘1’: External bus enabled (within the respective address window, see ADDRSEL)
RDYENx READY Input Enable
‘0’: External bus cycle is controlled by bit field MCTC only
‘1’: External bus cycle is controlled by the READY input signal
CSRENx Read Chip Select Enable
‘0’: The CS signal is independent of the read command (RD)
‘1’: The CS signal is generated for the duration of the read command
CSWENx Write Chip Select Enable
‘0’: The CS signal is independent of the write command (WR,WRL,WRH)
‘1’: The CS signal is generated for the duration of the write command
Bit Function
C165H
External Bus Interface
Data Sheet 186 2001-04-19
PRELIMINARY
- EXCERPT -
Bus Access Control
CPU accesses to internal and external busses, e.g. to internal or external memories or
peripherals, are controlled with the respective address ranges. These address ranges
are supported by ’chip select’ functions for XBUS resources or for external off-chip
resources. In the C165H six address ranges with according bus definitions can be
programmed for XBUS peripherals (including memories) and additionally five ranges for
external bus peripherals.
Note: In contrast to previous Infineon devices the XADRS/XBCON registers are not
hardwired but fully programmable.
Address ranges and address mapping of memories or peripherals on XBUS or external
bus are controlled with the address selection registers XADRSx for XBUS and
ADDRSELx for external bus. The respective bus type definitions are controlled with
registers XBCONx and BUSCONx.
In comparison to previous devices, C165H has 3 more address selection registers for
XBUS:
• The new register pair XADRS4 / XBCON4 use the same standard scheme of address
selection and XCS control as the XADRS1-3 registers; smallest possible address
range is 256 bytes.
• The new register pairs XADRS5 / XBCON5 and XADRS6 / XBCON6 control address
selections as defined for external peripherals (as contolled by ADDRSEL); thus,
mapping of XPER addresses to the total address space is provided, with smallest
possible address range of 4 K Bytes. XBCON5/6 and XCS5/6 control are identical to
the standard XBUS address ranges.
After reset, no address selection register is selected; thus the default address range is
enabled and controlled with BUSCON0 and additionally the chip select output CS0 is
activated (as in standard C16x architecture).
C165H
External Bus Interface
Data Sheet 187 2001-04-19
PRELIMINARY
- EXCERPT -
ADDRSEL1 (FE18H / 0CH) SFR Reset Value: 0000H
ADDRSEL2 (FE1AH / 0DH) SFR Reset Value: 0000H
ADDRSEL3(FE1CH / 0EH) SFR Reset Value: 0000H
ADDRSEL4 (FE1EH / 0FH) SFR Reset Value: 0000H
Note: There is no register ADDRSEL0, as register BUSCON0 controls all external
accesses outside the four address windows of BUSCON4...BUSCON1 within the
complete address space.
Definition of Address Areas
The four register pairs BUSCON4/ADDRSEL4...BUSCON1/ADDRSEL1 allow to define
4 separate address areas within the address space of the C165H. Within each of these
address areas external accesses can be controlled by one of the four different bus
modes, independent of each other and of the bus mode specified in register BUSCON0.
Each ADDRSELx register in a way cuts out an address window, within which the
Bit Function
RGSZ Range Size Selection
RGSAD Range Start Address
54321011 10 987615 14 13 12
rw
RGSAD RGSZ
rw
54321011 10 987615 14 13 12
rw
RGSAD RGSZ
rw
54321011 10 987615 14 13 12
rw
RGSAD RGSZ
rw
54321011 10 987615 14 13 12
rw
RGSAD RGSZ
rw
C165H
External Bus Interface
Data Sheet 188 2001-04-19
PRELIMINARY
- EXCERPT -
parameters in register BUSCONx are used to control external accesses. The range start
address of such a window defines the upper address bits, which are not used within the
address window of the specified size (see table below). For a given window size only
those upper address bits of the start address are used (marked “R”), which are not
implicitly used for addresses inside the window. The lower bits of the start address
(marked “x”) are disregarded.
XADRS1(2/3/4/5/6) (F014H / 0AH) ESFRx Reset Value: 0000H
The respective SFR addresses of XADRS registers can be found in list of SFRs.
Due to the different range size options, address mapping of XPERs is possible only
within the first MByte of the total address range if XADRS1 to XADRS4 is used. The
upper four address lines (A23:A20) are set to zero. Note that the range start address can
be only on boundaries specified by the selected range size.
Bit field
RGSZ
Resulting Window
Size
Relevant Bits (R) of Start Address
(A22...A12)
0 0 0 0
0 0 0 1
0 0 1 0
0 0 1 1
0 1 0 0
0 1 0 1
0 1 1 0
0 1 1 1
1 0 0 0
1 0 0 1
1 0 1 0
1 0 1 1
1 1 x x
4 KByte
8 KByte
16 KByte
32 KByte
64 KByte
128 KByte
256 KByte
512 KByte
1MByte
2 MByte
4 MByte
Reserved
Reserved.
RRRRRRRRRRR
RRRRRRRRRRx
RRRRRRRRRx x
RRRRRRRRx x x
RRRRRRRxxxx
RRRRRRxxxxx
RRRRRxxxxxx
RRRRxxxxxxx
RRRxxxxxxxx
RRxxxxxxxxx
Rxxxxxxxxxx
Bit Function
RGSAD Address Range Start Address Selection
RGSZ Address Range Size Selection
54321011 10 987615 14 13 12
rw- - - -
RGSZ
-
RGSAD
C165H
External Bus Interface
Data Sheet 189 2001-04-19
PRELIMINARY
- EXCERPT -
The following tables show the different definitions of range size selections and range
start addresses for the two types of address selections:
Range
Size
RGSZ
Selected
Address
Range
Relvant(R) bits of
RGSAD
Selected Range Start Address
(Relevant(R) bits of RGSAD)
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
11xx
256 Byte
512 Bytes
1 KB
2 KB
4 KB
8 KB
16 KB
32 KB
64 KBy
128 KB
256 KB
512 KB
- reserved
RRRR RRRR RRRR
RRRR RRRR RRR0
RRRR RRRR RR00
RRRR RRRR R000
RRRR RRRR 0000
RRRR RRR0 0000
RRRR RR00 0000
RRRR R000 0000
RRRR 0000 0000
RRR0 0000 0000
RR00 0000 0000
R000 0000 0000
0000 RRRR RRRR RRRR 0000 0000
0000 RRRR RRRR RRR0 0000 0000
0000 RRRR RRRR RR00 0000 0000
0000 RRRR RRRR R000 0000 0000
0000 RRRR RRRR 0000 0000 0000
0000 RRRR RRR0 0000 0000 0000
0000 RRRR RR00 0000 0000 0000
0000 RRRR R000 0000 0000 0000
0000 RRRR 0000 0000 0000 0000
0000 RRR0 0000 0000 0000 0000
0000 RR00 0000 0000 0000 0000
0000 R000 0000 0000 0000 0000
Table 25 Address Range and Address Range Start Definition of XADRS1/2/3/
4 register
C165H
External Bus Interface
Data Sheet 190 2001-04-19
PRELIMINARY
- EXCERPT -
The XBCONx registers are defined as follows:
Range
Size
RGSZ
Selected
Address
Range
Relvant(R) bits of
RGSAD
Selected Range Start Address
(Relevant(R) bits of RGSAD)
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
11xx
4 KB
8 KB
16 KB
32 KB
64 KB
128 KB
256 KB
512 KB
1 MB
2 MB
4 MB
8 MB
- reserved
RRRR RRRR RRRR
RRRR RRRR RRR0
RRRR RRRR RR00
RRRR RRRR R000
RRRR RRRR 0000
RRRR RRR0 0000
RRRR RR00 0000
RRRR R000 0000
RRRR 0000 0000
RRR0 0000 0000
RR00 0000 0000
R000 0000 0000
RRRR RRRR RRRR 0000 0000 0000
RRRR RRRR RRR0 0000 0000 0000
RRRR RRRR RR00 0000 0000 0000
RRRR RRRR R000 0000 0000 0000
RRRR RRRR 0000 0000 0000 0000
RRRR RRR0 0000 0000 0000 0000
RRRR RR00 0000 0000 0000 0000
RRRR R000 0000 0000 0000 0000
RRRR 0000 0000 0000 0000 0000
RRR0 0000 0000 0000 0000 0000
RR00 0000 0000 0000 0000 0000
R000 0000 0000 0000 0000 0000
Table 26 Address Range and Address Range Start Definition of XADRS5/6
Register
C165H
External Bus Interface
Data Sheet 191 2001-04-19
PRELIMINARY
- EXCERPT -
XBCON1/2/3 (F114H / 8AH) ESFR-b Reset Value: 0000H
Note: The ’BUSCON switch control’ BSWC is a new function, which is necessary due to
the execution with higher frequencies, to avoid bus collisions on data bus in case
of peripheral change (see BUSCON).
Note: All XADRSx/ADDRSELx registers as well as XBCONx/BUSCONx registers are
user programmable SFR registers. All BUSCONx registers are mapped into the
bitaddressable SFR memory space, all XBCONx registers are located in the
bitaddressable ESFR memory space. Although they are free programmable,
Bit Function
MCTCx Memory Cycle Time Control (see BUSCON)
RWDCx READ/WRITE Delay Control (see BUSCON)
MTTCx Memory Tri-state Time Control (see BUSCON)
BTYPx Bus Type Selection; only demultiplexed busses are supported on XBUS;
’00’: 8 bit bus
’10’: 16 bit bus; ’x1’: reserved.
EWENx Early Write Enable
’0’: Standard write enable signal control
’1’: Write active state is disabled one TCL earlier
ALECTLx ALE Lengthening Control Bit (see BUSCON)
BUSACTx* Bus Active Control
‘0’: XBUS (peripheral) disabled
‘1’: XBUS (peripheral) enabled
Enables the XBUS and the according chip select XCSx for the respective
address window (respective XBUS peripheral), selected with according XADRSx
window; after reset, all address windows on XBUS are disabled.
*not used in FC-Cores, where XBCON is hardwired.
BSWCx BUSCON Switch Control
’0’: Standard switch of bustype (switch of XBCON)
’1’: A bus wait state (Tri-state cycle) is included after execution of last old-
bustype cycle and before the first new-bustype cycle after switch of XBCON or
BUSCON; the BSWC bit is indicated in the old-bustype XBCON/BUSCON.
RDYENx READY Enable
’0’: The bus cycle length is controlled by the bus controller using MCTC
’1’: The bus cycle length is controlled by the peripheral using READY
BS
WCx
---RDY
ENx BUS
ACTx ALE
CTLx EW
ENx MT
TCx RW
DCx
54321011 10 987615 14 13 12
rwrw rw rw---rw
MCTCx
rw rw rw
BTYPx
rw
C165H
External Bus Interface
Data Sheet 192 2001-04-19
PRELIMINARY
- EXCERPT -
programming should be performed during the initialisation phase before the first
accesses are controlled with XBCONx or BUSCONx.
Note: The respective SFR addresses of XBCON registers can be found in list of SFRs.
Note: Within the C165H, register XBCON1 is related to the IOM-2 module. For
configuration, please also refer to Chapter 9.8, "Initialization of the C165H’s X-
peripherals" on page 199.
Address Window Arbitration
For each access the EBC compares the current address with all address select registers
(programmable ADDRSELx and hardwired XADRSx). This comparison is done in four
levels.
Priority 1: The XADRSx registers are evaluated first. A match with one of these registers directs the
access to the respective X-Peripheral using the corresponding XBCONx register and ignoring
all other ADDRSELx registers.
Priority 2: Registers ADDRSEL2 and ADDRSEL4 are evaluated before ADDRSEL1 and
ADDRSEL3, respectively. A match with one of these registers directs the access to
the respective external area using the corresponding BUSCONx register and ignoring
registers ADDRSEL1/3 (see figure below).
Priority 3: A match with registers ADDRSEL1 or ADDRSEL3 directs the access to the respective
external area using the corresponding BUSCONx register.
Priority 4: If there is no match with any XADRSx or ADDRSELx register the access to the external bus
uses register BUSCON0.
Figure 53 Address Window Arbitration
Note: Only the indicated overlaps are defined. All other overlaps lead to erroneous bus
cycles. Eg. ADDRSEL4 may not overlap ADDRSEL2 or ADDRSEL1. The
hardwired XADRSx registers are defined non-overlapping.
Active
Window
Inactive
Window
BUSCON0
BUSCON1
BUSCON2
XBCON0
BUSCON3
BUSCON4
C165H
External Bus Interface
Data Sheet 193 2001-04-19
PRELIMINARY
- EXCERPT -
RP0H (F108H / 84H) SFR Reset Value: - - XXH
Note: RP0H cannot be changed via software, but rather allows to check the current
configuration.
Precautions and Hints
• The external bus interface is enabled as long as at least one of the BUSCON registers
has its BUSACT bit set.
• PORT1 will output the intra-segment address as long as at least one of the BUSCON
registers selects a demultiplexed external bus, even for multiplexed bus cycles.
• Not all address areas defined via registers ADDRSELx may overlap each other. The
operation of the EBC will be unpredictable in such a case. See chapter „Address Window
Arbitration“.
• The address areas defined via registers ADDRSELx may overlap internal address
areas. Internal accesses will be executed in this case.
• For any access to an internal address area the EBC will remain inactive (see EBC Idle
State).
Bit Function
WRC Write Configuration
0: Pins WR and BHE operate as WRL and WRH signals
1: Pins WR and BHE operate as WR and BHE signals
CSSEL Chip Select Line Selection (Number of active CS outputs)
0 0: 3 CS lines: CS2...CS0
0 1: 2 CS lines: CS1...CS0
1 0: No CS lines at all
1 1: 5 CS lines: CS4...CS0 (Default without pulldowns)
SALSEL Segment Address Line Selection (Number of active segment address outputs)
0 0: 4-bit segment address: A19...A16
0 1: No segment address lines at all
1 0: 7-bit segment address: A22...A16
1 1: 2-bit segment address: A17...A16 (Default without pulldowns)
CLKCFG Clock Generation Mode Configuration
These pins define the clock generation mode, ie. the mechanism how the the
internal CPU clock is generated from the externally applied (XTAL1) input clock.
WRC
54321011 10 987615 14 13 12
r r---- r----
CSSELSALSEL
r
CLKCFG
C165H
External Bus Interface
Data Sheet 194 2001-04-19
PRELIMINARY
- EXCERPT -
9.5 EBC Idle State
When the external bus interface is enabled, but no external access is currently executed,
the EBC is idle. As long as only internal resources (from an architecture point of view)
like IRAM, GPRs or SFRs, etc. are used the external bus interface does not change (see
table below).
Accesses to on-chip X-Peripherals are also controlled by the EBC. However, even
though an X-Peripheral appears like an external peripheral to the controller, the
respective accesses do not generate valid external bus cycles.
Due to timing constraints address and write data of an XBUS cycle are reflected on the
external bus interface (see table below). The „address“ mentioned above includes
PORT1, Port 4, BHE and ALE which also pulses for an XBUS cycle. The external CS
signals on Port 6 are driven inactive (high) because the EBC switches to an internal XCS
signal.
The external control signals (RD and WR or WRL/WRH if enabled) remain inactive
(high).
Table 27 Status of the external bus interface during EBC idle state:
9.6 External Bus Arbitration
In high performance systems it may be efficient to share external resources like memory
banks or peripheral devices among more than one controller. The C165H supports this
approach with the possibility to arbitrate the access to its external bus, ie. to the external
devices.
Pins Internal accesses only XBUS accesses
PORT0 Tristated (floating) Tristated (floating) for read accesses
XBUS write data for write accesses
PORT1 Last used external address
(if used for the bus interface)
Last used XBUS address
(if used for the bus interface)
Port 4 Last used external segment address
(on selected pins)
Last used XBUS segment address
(on selected pins)
Port 6 Active external CS signal corresponding
to last used address
Inactive (high) for selected CS signals
BHE Level corresponding to last external
access
Level corresponding to last XBUS
access
ALE Inactive (low) Pulses as defined for X-Peripheral
RD Inactive (high) Inactive (high)
WR/WRL Inactive (high) Inactive (high)
WRH Inactive (high) Inactive (high)
C165H
External Bus Interface
Data Sheet 195 2001-04-19
PRELIMINARY
- EXCERPT -
This bus arbitration allows an external master to request the C165H’s bus via the HOLD
input. The C165H acknowledges this request via the HLDA output and will float its bus
lines in this case. The CS outputs provide internal pullup devices. The new master may
now access the peripheral devices or memory banks via the same interface lines as the
C165H. During this time the C165H can keep on executing, as long as it does not need
access to the external bus. All actions that just require internal resources like instruction
or data memory and on-chip peripherals, may be executed in parallel.
When the C165H needs access to its external bus while it is occupied by another bus
master, it demands it via the BREQ output.
The external bus arbitration is enabled by setting bit HLDEN in register PSW to ‘1’. In
this case the three bus arbitration pins HOLD, HLDA and BREQ are automatically
controlled by the EBC independent of their I/O configuration. Bit HLDEN may be cleared
during the execution of program sequences, where the external resources are required
but cannot be shared with other bus masters. In this case the C165H will not answer to
HOLD requests from other external masters. If HLDEN is cleared while the C165H is in
Hold State (code execution from internal RAM) this Hold State is left only after HOLD has
been deactivated again. Ie. in this case the current Hold State continues and only the
next HOLD request is not answered.
Connecting eg. two C165Hs in this way would require additional logic to combine the
respective output signals HLDA and BREQ. This can be avoided by switching one of the
controllers into Slave Mode where pin HLDA is switched to input. This allows to directly
connect the slave controller to another master controller without glue logic. The Slave
Mode is selected by setting bit DP6.7 to ’1’. DP6.7=’0’ (default after reset) selects the
Master Mode.
Note: The pins HOLD, HLDA and BREQ keep their alternate function (bus arbitration)
even after the arbitration mechanism has been switched off by clearing HLDEN.
All three pins are used for bus arbitration after bit HLDEN was set once.
Connecting Bus Masters
When multiple C165Hs or a C165H and another bus master shall share external
resources some glue logic is required that defines the currently active bus master and
also enables a C165H which has surrendered its bus interface to regain control of it in
case it must access the shared external resources. This glue logic is required if the
„other“ bus master does not automatically remove its hold request after having used the
shared resources.
When two C165Hs are to be connected in this way the external glue logic can be left out.
In this case one of the controllers must be operated in its Master Mode (default after
reset, DP6.7=’0’) while the other one must be operated in its Slave Mode (selected with
DP6.7=’1’).
C165H
External Bus Interface
Data Sheet 196 2001-04-19
PRELIMINARY
- EXCERPT -
In Slave Mode the C165H inverts the direction of its HLDA pin and uses it as an input,
while the master’s HLDA pin remains an output. This approach does not require any
additional glue logic for the bus arbitration (see figure below).
Figure 54 Sharing External Resources using Slave Mode
When the bus arbitration is enabled (HLDEN=’1’) the three corresponding pins are
automatically controlled by the EBC. Normally the respective port direction register bits
retain their reset value which is ’0’. This selects Master Mode where the device operates
compatible with earlier versions. Slave Mode is enabled by intentionally switching pin
BREQ to output (DP6.7=’1’) which is neither required for Master Mode nor for earlier
devices.
Entering the Hold State
Access to the C165H’s external bus is requested by driving its HOLD input low. After
synchronizing this signal the C165H will complete a current external bus cycle (if any is
active), release the external bus and grant access to it by driving the HLDA output low.
During hold state the C165H treats the external bus interface as follows:
• Address and data bus(es) float to tri-state
• ALE is pulled low by an internal pulldown device
• Command lines are pulled high by internal pullup devices (RD, WR/WRL, BHE/WRH)
• CSx outputs are pulled high (push/pull mode) or float to tri-state (open drain mode)
Should the C165H require access to its external bus during hold mode, it activates its
bus request output BREQ to notify the arbitration circuitry. BREQ is activated only during
hold mode. It will be inactive during normal operation.
C165H in
Master Mode
BREQ
HLDA
HOLD
C165H in
Slave Mode
BREQ
HLDA
HOLD
C165H
External Bus Interface
Data Sheet 197 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 55 External Bus Arbitration, Releasing the Bus
Note: The C165H will complete the currently running bus cycle before granting bus
access as indicated by the broken lines. This may delay hold acknowledge
compared to this figure.
The figure above shows the first possibility for BREQ to get active.
During bus hold pin P3.12 is switched back to its standard function and is then
controlled by DP3.12 and P3.12. Keep DP3.12 = ’0’ in this case to ensure floating
in hold mode.
Exiting the Hold State
The external bus master returns the access rights to the C165H by driving the HOLD
input high. After synchronizing this signal the C165H will drive the HLDA output high,
actively drive the control signals and resume executing external bus cycles if required.
Depending on the arbitration logic, the external bus can be returned to the C165H under
two circumstances:
• The external master does no more require access to the shared resources and gives
up its own access rights, or
• The C165H needs access to the shared resources and demands this by activating its
BREQ output. The arbitration logic may then deactivate the other master’s HLDA and so
free the external bus for the C165H, depending on the priority of the different masters.
Note: The Hold State is not terminated by clearing bit HLDEN.
MCD02238
HOLD
HLDA
BREQ
CSx
~
~~
~~
~~
~~
~
Signals
~
~~
~
Other
C165H
External Bus Interface
Data Sheet 198 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 56 External Bus Arbitration, (Regaining the Bus)
Note: The falling BREQ edge shows the last chance for BREQ to trigger the indicated
regain-sequence. Even if BREQ is activated earlier the regain-sequence is
initiated by HOLD going high. BREQ and HOLD are connected via an external
arbitration circuitry. Please note that HOLD may also be deactivated without the
C165H requesting the bus.
9.7 XBUS Interface
The C165H provides an on-chip interface (the XBUS interface), which allows to connect
integrated customer/application specific peripherals to the standard controller core. The
XBUS is an internal representation of the external bus interface, ie. it is operated in the
same way.
The current XBUS interface is prepared to support up to 3 X-Peripherals.
For each peripheral on the XBUS (X-Peripheral) there is a separate address window
controlled by an XBCON and an XADRS register. As an interface to a peripheral in many
cases is represented by just a few registers, the XADRS registers select smaller address
windows than the standard ADDRSEL registers. As the register pairs control integrated
peripherals rather than externally connected ones, they are fixed by mask programming
rather than being user programmable.
MCD02236
Other
Signals
CSx
BREQ
HLDA
HOLD
C165H
External Bus Interface
Data Sheet 199 2001-04-19
PRELIMINARY
- EXCERPT -
X-Peripheral accesses provide the same choices as external accesses, so these
peripherals may be bytewide or wordwide, with or without a separate address bus.
Interrupt nodes and configuration pins (on PORT0) are provided for X-Peripherals to be
integrated.
9.8 Initialization of the C165H’s X-peripherals
The following registers must be set for initialization of the C165H X-peripherals:
XPERCON-Register (Addr. F024, default: 0000):
Bit 5: '1': IOM-2 active '0': IOM-2 switched-off
SYSCON-Register (Addr. FF12, default: 0xx0):
Bit 2: '1': X-Peripherals enable '0': X-Peripherals disable
Bit 1: '1': X-Per accesses visible at externalXBUS'0': X-Per accesses not visible
SYSCON3-Register (Addr. F1D4, default: 0000):
Bit 15: '1': All peripheral clocks disabled '0': Individual disable control by
bits 14 thru 0
Bit 6: '1': Disable IOM-2 clock '0': Enable IOM-2 clock
Bit 3: '1': Disable GPT12 clock '0': Enable GPT12 clock
Bit 2: '1': Disable SSC clock '0': Enable SSC clock
Bit 1: '1': Disable ASC clock '0': Enable ASC clock
Bit 0: '1': Disable RTC clock '0': Enable RTC clock
XBCON1-Register (Addr.F114, default: 0000H):
Definition of the IOM-2 bus protocol.
Must be set to ’048xH’. Recommended using 0 waitstates: ’048FH’.
XBCON2-Register (Addr.F116, default: 0000H):
This register is not used. Must be set to ’0000H’.
XBCON3-Register (Addr.F118, default: 0000H):
This register is not used. Must be set to ’0000H’.
XADRS1-Register (Addr.F014, default: UUUU):
Definition of the IOM-2 address space. Should be initialized with ’0EF0H’ before writing
to XBCON1.
C165H
General Purpose Timer Unit
Data Sheet 200 2001-04-19
PRELIMINARY
- EXCERPT -
10 General Purpose Timer Unit
The General Purpose Timer Unit (GPT) represents very flexible multifunctional timer
structures which may be used for timing, event counting, pulse width measurement,
pulse generation, frequency multiplication, and other purposes.
In the C165H, there are following alternate function pins available: P3.3/T3OUT, P3.5/
T4IN/T3EUD/T2EUD, P3.6/T3IN and P3.7/T2IN, as shown in Figure 57.
Figure 57 GPT module external pins
GPT1 Core
Timer 3
GPT1 Core
Timer 4
GPT2 Core
Timer 5
GPT1 Core
Timer 2
GPT2 Core
Timer 6
P3.6
P3.7
P3.5
T2IN
T2EUD
T3IN
T3EUD
T4IN
P3.3
T3OUT
gpt12utahimpl
T3OTL
interrupt request
T2IC.T2IR
interrupt request
T4IC.T4IR
interrupt request
T5IC.T5IR
interrupt request
T6IC.T6IR
interrupt request
T3IC.T3IR
T6OTL
GPT2 CAPREL
interrupt request
CRIC.CRIR
Note: In the C165H, there are no external pins connected to Timer 5 and Timer 6.
Additional, there is no second external connection to Timer 4 (T4EUD) and no
external connection to the register GPT2 CAPREL.
C165H
General Purpose Timer Unit
Data Sheet 201 2001-04-19
PRELIMINARY
- EXCERPT -
The GPT incorporate five 16-bit timers that are grouped into the two timer blocks GPT1
and GPT2. Each timer in each block may operate independently in a number of different
modes such as gated timer or counter mode, or may be concatenated with another timer
of the same block.
Block 1 contains 3 timers/counters with a maximum resolution of fTimer/4. The auxiliary
timers of GPT1 may optionally be configured as reload or capture registers for the core
timer.
Block 2 contains 2 internal timers/counters with a maximum resolution of fTimer/2. An
additional CAPREL register supports capture and reload operation with extended
functionality.
The following enumeration summarizes all features to be supported:
• Timer Block 1:
–f
Timer/4 maximum resolution.
– 3 independent timers/counters.
– Timers/counters can be concatenated.
– 4 operating modes (timer, gated timer, counter, incremental).
– Separate interrupt nodes.
• Timer Block 2:
–f
Timer/2 maximum resolution.
– 2 independent timers/counters.
– Timers/counters can be concatenated.
– 2 operating modes (timer, counter).
– Capture/reload functions via 16-bit Capture/Reload register CAPREL.
– Separate interrupt nodes.
10.1 Kernel Description
10.1.1 Functional Description of Timer Block 1
All three timers of block 1 (T2, T3, T4) can run in 4 basic modes, which are timer, gated
timer, counter and incremental interface mode, and all timers can either count up or
down.
The input line (TxIN) associated with it which serves as the gate control in gated timer
mode, or as the count input in counter mode. The count direction (Up / Down) may be
programmed via software or may be dynamically altered by a signal at an external
control input line. An overflow/underflow of core timer T3 is indicated by the output toggle
latch T3OTL whose state may be output on related line T3OUT.
C165H
General Purpose Timer Unit
Data Sheet 202 2001-04-19
PRELIMINARY
- EXCERPT -
The auxiliary timers T2 and T4 may additionally be concatenated with the core timer, or
used as capture or reload registers for the core timer.
The current contents of each timer can be read or modified by the CPU by accessing the
corresponding timer registers T2, T3, or T4, which are located in the non-bitaddressable
SFR space. When any of the timer registers is written to by the CPU in the state
immediately before a timer increment, decrement, reload, or capture is to be performed,
the CPU write operation has priority in order to guarantee correct results.
Figure 58 Structure of Timer Block 1
10.1.1.1 Core Timer T3
The operation of the core timer T3 is controlled by its bitaddressable control register
T3CON.
T3
Mode
Control
2
n
: 1
2
n
: 1
f
hw_clk
T2
Mode
Control
GPT1 Timer T2
Reload
Capture
2
n
: 1
T4
Mode
Control GPT1 Timer T4
Reload
Capture
GPT1 Timer T3 T3OTL
U/D
T2EUD
T2IN
T3IN
T3EUD
T4IN
T3OUT
Toggle FF
U/D
U/D
Interrupt
Request
Interrupt
Request
Interrupt
Request
MCT02141
f
hw_clk
f
hw_clk
T3OTL
T3OTL
C165H
General Purpose Timer Unit
Data Sheet 203 2001-04-19
PRELIMINARY
- EXCERPT -
Run Control
The timer can be started or stopped by software through bit T3R (Timer T3 Run Bit).
Setting bit T3R to ‘1’ will start the timer, clearing T3R stops the timer.
In gated timer mode, the timer will only run if T3R = ‘1’ and the gate is active (high or low,
as programmed).
Note: When bit T2RC/T4RC in timer control register T2CON/T4CON is set to ’1’, T3R
will also control (start and stop) auxiliary timer T2/T4.
Count Direction Control
The count direction of the core timer can be controlled either by software or by the
external input line T3EUD (Timer T3 External Up/Down Control Input). These options are
selected by bits T3UD and T3UDE in control register T3CON. When the up/down control
is done by software (bit T3UDE = ‘0’), the count direction can be altered by setting or
clearing bit T3UD. When T3UDE = ‘1’, line T3EUD is selected to be the controlling
source of the count direction. However, bit T3UD can still be used to reverse the actual
count direction, as shown in the table below. If T3UD = ‘0’ and line T3EUD shows a low
level, the timer is counting up. With a high level at T3EUD the timer is counting down. If
T3UD = ‘1’, a high level at line T3EUD specifies counting up, and a low level specifies
counting down. The count direction can be changed regardless of whether the timer is
running or not.
When line T3EUD is used as external count direction control input, its associated port
pin must be configured as input.
Note: The direction control works the same for core timer T3 and for auxiliary timer T2.
For timer T4, no T4EUD input exist, therefore the count direction can be controlled
by software only.
Table 28 GPT1 Core Timer T3 Count Direction Control
Line TxEUD Bit TxUDE Bit TxUD Count Direction
X 0 0 Count Up
X 0 1 Count Down
0 1 0 Count Up
1 1 0 Count Down
0 1 1 Count Down
1 1 1 Count Up
C165H
General Purpose Timer Unit
Data Sheet 204 2001-04-19
PRELIMINARY
- EXCERPT -
Timer 3 Overflow/Underflow Monitoring
An overflow or underflow of timer T3 will clock the overflow toggle latch T3OTL in control
register T3CON. T3OTL can also be set or reset by software. Bit T3OE (Overflow/
Underflow Output Enable) in register T3CON enables the state of T3OTL to be
monitored via an external line T3OUT. If this line is linked to an external port pin, which
has to be configured as output, T3OTL can be used to control external HW.
In addition, T3OTL can be used in conjunction with the timer over/underflows as an input
for the counter function or as a trigger source for the reload function of the auxiliary
timers T2 and T4. For this purpose, the state of T3OTL does not have to be available at
any port pin, because an internal connection is provided for this option.
Timer 3 in Timer Mode
Timer mode for the core timer T3 is selected by setting bit field T3M in register T3CON
to ‘000B’.
In this mode, T3 is clocked with the module clock fTimer divided by a programmable
prescaler, which is controlled by bit field T3I and bit FM1. The input frequency fT3 for timer
T3 and its resolution rT3 are scaled linearly with lower module clock frequencies, as can
be seen from the following formula:
This formula also applies to the Gated Timer Mode of T3 and to the auxiliary timers T2
and T4 in timer and gated timer mode, where applicable.
Table 29 Example for Timer 3 Frequencies and Resolutions
fTimer [MHz] T3I FM1 fT3 [KHz] rT3 [µs]
24 ’111’ 0 23.44 42.67
24 ’000’ 1 6000.0 0.17
36 ’000’ 0 4500.0 0.22
36 ’100’ 0 281.25 3.55
36 ’111’ 1 70.31 14.22
fT3 = fTimer
8 * 2<T3I - FM1> rT3 [µs] = fTimer [MHz]
8 * 2<T3I - FM1>
C165H
General Purpose Timer Unit
Data Sheet 205 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 59 Block Diagram of Core Timer T3 in Timer Mode
Timer 3 in Gated Timer Mode
Gated timer mode for the core timer T3 is selected by setting bit field T3M in register
T3CON to ‘010B’ or ‘011B’.
Bit T3M.0 (T3CON.3) selects the active level of the gate input. In gated timer mode the
same options for the input frequency as for the timer mode are available. However, the
input clock to the timer in this mode is gated by the external input line T3IN (Timer T3
External Input), which is an alternate function of P3.6.
To enable this operation pin P3.6/T3IN must be configured as input, ie. direction control
bit DP3.6 must contain ’0’.
Core Timer Tx
TxOTL
Interrupt
Request
TxR
2
n
: 1
Txl
Up/
Down
TxUDE
MCB02028
f
hw_clk
TxUD
x=3
C165H
General Purpose Timer Unit
Data Sheet 206 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 60 Block Diagram of Core Timer T3 in Gated Timer Mode
If T3M = ‘010B’, the timer is enabled when T3IN shows a low level. A high level at this
line stops the timer. If T3M = ‘011B’, line T3IN must have a high level in order to enable
the timer. In addition, the timer can be turned on or off by software using bit T3R. The
timer will only run, if T3R = ‘1’ and the gate is active. It will stop, if either T3R = ‘0’ or the
gate is inactive.
Note: A transition of the gate signal at line T3IN does not cause an interrupt request.
Timer 3 in Counter Mode
Counter mode for the core timer T3 is selected by setting bit field T3M in register T3CON
to ‘001B’. In counter mode timer T3 is clocked by a transition at the external input pin
T3IN, which is an alternate function of P3.6. The event causing an increment or
decrement of the timer can be a positive, a negative, or both a positive and a negative
transition at this line. Bit field T3I in control register T3CON selects the triggering
transition (see Table 30 below).
Core Tim er Tx TxOTL
Interrupt
Request
TxOE
TxOUT
TxR
MUX
XOR
0
MUX
1
Up/
Down
TxEUD
TxUDE
MCB02029
TxUD
2
n
: 1
TxI
f
hw_clk
TxM
TxIN
x=3
C165H
General Purpose Timer Unit
Data Sheet 207 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 61 Block Diagram of Core Timer T3 in Counter Mode
Table 30 Core Timer T3 (Counter Mode) Input Edge Selection
For counter operation, a port pin P3.6/T3IN must be configured as input. The maximum
input frequency which is allowed in counter mode is fTimer/8 (FM1 = ’1’). To ensure that a
transition of the count input signal which is applied to T3IN is correctly recognized, its
level should be held high or low for at least 4 fTimer cycles (FM1 = ’1’) before it changes.
Timer 3 in Incremental Interface Mode
Incremental Interface mode for the core timer T3 is selected by setting bit field T3M in
register T3CON to ‘110B’ or ‘111B’. In incremental interface mode pin P3.6/T3IN
(configured as timer input T3IN) and pin P3.5/T3EUD (configured as timer input) are
used to interface to an incremental encoder.
Note: In the C165H, the T3EUD timer input is connected to P3.5. In this case, Timer 4
input T4IN can be used by Software only.
T3I Triggering Edge for Counter Increment / Decrement
0 0 0 None. Counter T3 is disabled
0 0 1 Positive transition (rising edge) on T3IN
0 1 0 Negative transition (falling edge) on T3IN
0 1 1 Any transition (rising or falling edge) on T3IN
1 X X Reserved. Do not use this combination
Core Timer Tx
TxR
XOR
0
MUX
1
Up/
Down
TxEUD
TxUDE
MCB02030
Txl
TxIN
Edge
Select
TxOTL
Interrupt
Request
TxOE
TxOUT
TxUD
x=3
C165H
General Purpose Timer Unit
Data Sheet 208 2001-04-19
PRELIMINARY
- EXCERPT -
T3 is clocked by each transition on one or both of the external input lines which gives 2-
fold or 4-fold resolution of the encoder input.
Figure 62 Block Diagram of Core Timer T3 in Incremental Interface Mode
Bit field T3I in control register T3CON selects the triggering transitions (see table below).
In this mode the sequence of the transitions of the two input signals is evaluated and
generates count pulses as well as the direction signal. Depending on the chosen
Incremental Intrerface Mode, Rotation detection ‘110B’ or Edge Detection ‘111B’, an
interrupt can be generated. This interrupt is only generated if it’s enabled by setting bit
T3IREN in register T3CON. For the Rotation detection an interrupt will be generated
each time the count direction of timer 3 changes. For the Edge detection an interrupt will
be generated each time a count action for timer 3 occurs. Count direction, changes in
the count direction and count requests are monitored through the status bits T3RDIR,
T3CHDIR and T3EDGE in register T3CON. T3 is modified automatically according to the
speed and the direction of the incremental encoder. Therefore, the contents of timer T3
always represents the encoder’s current position.
Table 31 Core Timer T3 (Incremental Interface Mode) Input Edge Selection
T3I Triggering Edge for Counter Increment / Decrement
0 0 0 None. Counter T3 stops.
0 0 1 Any transition (rising or falling edge) on T3IN.
0 1 0 Any transition (rising or falling edge) on T3EUD.
Edge
Select Timer T3
XOR MUX
T3EUD
T3UDE
MCB03998
T3l
T3IN T3OTL
Interrupt
Request
T3OUT
Phase
Detect
T3OE
T3R
Edge
Interrupt
T3
Edge
T3UD
T3
CHDIR
0
1
Change
Detection
T3
RDIR
Rotation
Interrupt
T3M
Up/
Down
T3M
C165H
General Purpose Timer Unit
Data Sheet 209 2001-04-19
PRELIMINARY
- EXCERPT -
The incremental encoder can be connected directly to the microcontroller without
external interface logic. In a standard system, however, comparators will be employed
to convert the encoder’s differential outputs (e.g. A, A) to digital signals (e.g. A). This
greatly increases noise immunity.
Note: The third encoder output T0, which indicates the mechanical zero position, may
be connected to an external interrupt input and trigger a reset of timer T3.
Figure 63 Interfacing the Encoder to the Microcontroller
For incremental interface operation the following conditions must be met:
l Bitfield T3M must be ’110B’ or ‘111B’.
l Pins associated to lines T3IN and T3EUD must be configured as input.
l Bit T3UDE must be ’1’ to enable automatic direction control.
The maximum input frequency which is allowed in incremental interface mode is fTimer/8
(FM = 1). To ensure that a transition of any input signal is correctly recognized, its level
should be held high or low for at least 4 fTimer cycles (FM = 1) before it changes.
In Incremental Interface Mode the count direction is automatically derived from the
sequence in which the input signals change, which corresponds to the rotation direction
of the connected sensor. The table below summarizes the possible combinations.
The figures below give examples of T3’s operation, visualizing count signal generation
and direction control. It also shows how input jitter is compensated which might occur if
the sensor rests near to one of its switching points.
0 1 1 Any transition (rising or falling edge) on any T3 input (T3IN or T3EUD).
1 X X Reserved. Do not use this combination
Table 31 Core Timer T3 (Incremental Interface Mode) Input Edge Selection
T3I Triggering Edge for Counter Increment / Decrement
A
A
B
B
T0
T0
A
B
T0
External
T3input
T3input
Interrupt
Encoder
Signal Conditioning
+
-
+
-
+
-
Micro-
controller
C165H
General Purpose Timer Unit
Data Sheet 210 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 64 Evaluation of the Incremental Encoder Signals
Table 32 Core Timer T3 (Incremental Interface Mode) Count Direction
Level on respective
other input
T3IN Input T3EUD Input
Rising Falling Rising Falling
High Down Up Up Down
Low Up Down Down Up
T3IN
T3EUD
Contents
of T3
Forward ForwardBackward JitterJitter
Up
Down
Up
Note: This example shows the timer behavior assuming that T3 counts upon any
transition on any input, i.e. T3I = ’011B’.
C165H
General Purpose Timer Unit
Data Sheet 211 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 65 Evaluation of the Incremental Encoder Signals
Note: Timer T3 operating in incremental interface mode automatically provides
information on the sensor’s current position. Dynamic information (speed,
acceleration, deceleration) may be obtained by measuring the incoming signal
periods.
10.1.1.2 Auxiliary Timers T2 and T4
Note: For the external pin connection of the timer T2 and timer T4, please refer to
Figure 57, page 200.
Both auxiliary timers T2 and T4 have exactly the same functionality with the only
restriction of the availibility of external pins connected to each timer. Timer T2 can be
configured for timer, gated timer, counter, or incremental interface mode. Timer T4 can
be configured for timer, gated timer and counter mode. In addition, the auxiliary timers
can be concatenated with the core timer, or they may be used as reload or capture
registers in conjunction with the core timer.
Note: Timer 2 input T2EUD is connected to P3.5. When the external input for T2EUD is
used (P3.5 configured as input), T4IN and T3EUD can be used by Software
(internal) only.
The individual configuration for timers T2 and T4 is determined by their bitaddressable
control registers T2CON and T4CON, which are both organized identically. Note that
functions which are present in all 3 timers of timer block 1 are controlled in the same bit
positions and in the same manner in each of the specific control registers.
T3IN
T3EUD
Contents
of T3
Forward ForwardBackward JitterJitter
Up
Down
Up
Note: This example shows the timer behavior assuming that T3 counts upon any
transition on input T3IN, i.e. T3I = ’001B’.
C165H
General Purpose Timer Unit
Data Sheet 212 2001-04-19
PRELIMINARY
- EXCERPT -
Run control for auxiliary timers T2 and T4 can be handled by the associated Run Control
Bit T2R, T4R in register T2CON/T4CON. Alternatively, a remote control option (T2RC,
T4RC = ’1’) may be enabled to start and stop T2/T4 via the run bit T3R of core timer T3.
Timers T2 and T4 in Timer Mode or Gated Timer Mode
When the auxiliary timers T2 and T4 are programmed to timer mode or gated timer
mode, their operation is the same as described for the core timer T3. The descriptions,
figures and tables apply accordingly with two exceptions:
• There is no TxOUT output line for T2 and T4.
• There is no T4EUD input. Therefore Software must be programmed accordingly.
• Overflow/Underflow Monitoring is not supported (no output toggle latch).
Timer T2 in Counter Mode
In counter mode timer T2 can be clocked either by a transition at the respective external
input line T2IN, or by a transition of timer T3’s output toggle latch T3OTL.
Figure 66 Block Diagram of the Auxiliary Timer T2 in Counter Mode
The event causing an increment or decrement of the timer T2 can be a positive, a
negative, or both a positive and a negative transition at either the input line, or at the
output toggle latch T3OTL.
Bit field T2I in the respective control register T2CON selects the triggering transition (see
table below).
Auxiliary Timer T2 Interrupt
Request
T2R
Up/
Down
T2UD
T2UDE
MCB02221UTAH
T2l
T2IN/
T3OTL
Edge
Select
C165H
General Purpose Timer Unit
Data Sheet 213 2001-04-19
PRELIMINARY
- EXCERPT -
Note: Only state transitions of T3OTL which are caused by the overflows/underflows of
T3 will trigger the counter function of T2. Modifications of T3OTL via software will
NOT trigger the counter function of T2.
For counter operation, an external pin associated to line T2IN must be configured as
input. The maximum input frequency which is allowed in counter mode is fTimer/8 (FM1 =
’1’). To ensure that a transition of the count input signal which is applied to T2IN is
correctly recognized, its level should be held for at least 4 fTimer cycles (FM1 = ’1’) before
it changes.
Timer T4 in Counter Mode
The operation of Timer T4 in counter mode is exactly the same as described for Timer T2
in Chapter "Timer T2 in Counter Mode" above.
10.1.1.3 Timer Concatenation
Using the output toggle latch T3OTL as a clock source for an auxiliary timer in counter
mode concatenates the core timer T3 with the respective auxiliary timer. Depending on
which transition of T3OTL is selected to clock the auxiliary timer, this concatenation
forms a 32-bit or a 33-bit timer/counter.
•32-bit Timer/Counter: If both a positive and a negative transition of T3OTL is used to
clock the auxiliary timer, this timer is clocked on every overflow/underflow of the core
timer T3. Thus, the two timers form a 32-bit timer.
•33-bit Timer/Counter: If either a positive or a negative transition of T3OTL is selected
to clock the auxiliary timer, this timer is clocked on every second overflow/underflow
of the core timer T3. This configuration forms a 33-bit timer (16-bit core
timer+T3OTL+16-bit auxiliary timer).
Table 33 Auxiliary Timer T2 (Counter Mode) Input Edge Selection
T2I Triggering Edge for Counter Increment / Decrement
X 0 0 None. Counter T2 is disabled
0 0 1 Positive transition (rising edge) on T2IN
0 1 0 Negative transition (falling edge) on T2IN
0 1 1 Any transition (rising or falling edge) on T2IN
1 0 1 Positive transition (rising edge) of output toggle latch T3OTL
1 1 0 Negative transition (falling edge) of output toggle latch T3OTL
1 1 1 Any transition (rising or falling edge) of output toggle latch T3OTL
C165H
General Purpose Timer Unit
Data Sheet 214 2001-04-19
PRELIMINARY
- EXCERPT -
The count directions of the two concatenated timers are not required to be the same.
This offers a wide variety of different configurations.
T3 can operate in timer, gated timer or counter mode in this case.
Figure 67 Concatenation of Core Timer T3 and an Auxiliary Timer
Auxiliary Timer in Reload Mode
Reload mode for the auxiliary timers T2 and T4 is selected by setting bit field TxM in the
respective register TxCON to ‘100B’. In reload mode the core timer T3 is reloaded with
the contents of an auxiliary timer register, triggered by one of two different signals. The
trigger signal is selected the same way as the clock source for counter mode (see table
above), i.e. a transition of the auxiliary timer’s input or the output toggle latch T3OTL may
trigger the reload.
Note: When programmed for reload mode, the respective auxiliary timer (T2 or T4) stops
independent of its run flag T2R or T4R.
Core Timer T3 T3OTL
Interrupt
Request
T3R
2
n
: 1
T3l
MCB02034gpt1
f
hw_clk
Up/Down
Auxiliary Timer Tx
TxR
Txl
Edge
Select
TxIR Interrupt
Request
*)
T3OE
T3OUT
Note: Line ’*’ only affected by over/underflows of T3, but NOT by software
modifications of T3OTL.
x = 2,4
C165H
General Purpose Timer Unit
Data Sheet 215 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 68 GPT1 Auxiliary Timer in Reload Mode
Upon a trigger signal T3 is loaded with the contents of the respective timer register (T2
or T4) and the interrupt request flag (T2IR or T4IR) is set.
Note: When a T3OTL transition is selected for the trigger signal, also the interrupt
request flag T3IR will be set upon a trigger, indicating T3’s overflow or underflow.
Modifications of T3OTL via software will NOT trigger the counter function of T2/T4.
The reload mode triggered by T3OTL can be used in a number of different
configurations. Depending on the selected active transition the following functions can
be performed:
• If both a positive and a negative transition of T3OTL is selected to trigger a reload, the
core timer will be reloaded with the contents of the auxiliary timer each time it
overflows or underflows. This is the standard reload mode (reload on overflow/
underflow).
• If either a positive or a negative transition of T3OTL is selected to trigger a reload, the
core timer will be reloaded with the contents of the auxiliary timer on every second
overflow or underflow.
• Using this “single-transition” mode for both auxiliary timers allows to perform very
flexible pulse width modulation (PWM). One of the auxiliary timers is programmed to
reload the core timer on a positive transition of T3OTL, the other is programmed for a
Reload Register Tx
Core Timer T3
Up/Down
Source/Edge
Select
T3OTL
Interrupt
Request
T3OE
T3OUT
TxIN
Input
Clock
TxI
*)
Interrupt
Request
MCB02035UTAH
Note: Line ’*’
only
x = (2, 4)
C165H
General Purpose Timer Unit
Data Sheet 216 2001-04-19
PRELIMINARY
- EXCERPT -
reload on a negative transition of T3OTL. With this combination the core timer is
alternately reloaded from the two auxiliary timers.
The figure below shows an example for the generation of a PWM signal using the
alternate reload mechanism. T2 defines the high time of the PWM signal (reloaded on
positive transitions) and T4 defines the low time of the PWM signal (reloaded on negative
transitions). The PWM signal can be output on line T3OUT if the control bit T3OE is set
to ‘1’. With this method the high and low time of the PWM signal can be varied in a wide
range.
Note: The output toggle latch T3OTL is accessible via software and may be changed, if
required, to modify the PWM signal. However, this will NOT trigger the reloading
of T3.
Note: An associated port pin linked to line T3OUT should be configured as output.
Figure 69 GPT1 Timer Reload Configuration for PWM Generation
Core Timer T3
Up/Down
T3OTL
Interrupt
Request
T3OE
T3OUT
Interrupt
Request
Reload Register T2
Interrupt
Request
Reload Register T4
T2I
*)
*)
T4I
Input
Clock
MCB02037
Note: Lines ’*’ only affected by over/underflows of T3, but NOT by software
modifications of T3OTL.
C165H
General Purpose Timer Unit
Data Sheet 217 2001-04-19
PRELIMINARY
- EXCERPT -
Note: Although it is possible, it should be avoided to select the same reload trigger event
for both auxiliary timers. In this case both reload registers would try to load the
core timer at the same time. If this combination is selected, T2 is disregarded and
the contents of T4 is reloaded.
Auxiliary Timer in Capture Mode
Capture mode for the auxiliary timers T2 and T4 is selected by setting bit field TxM in the
respective register TxCON to ‘101B’. In capture mode the contents of the core timer are
latched into an auxiliary timer register in response to a signal transition at the respective
auxiliary timer's external input line TxIN. The capture trigger signal can be a positive, a
negative, or both a positive and a negative transition.
The two least significant bits of bit field TxI are used to select the active transition (see
table in the counter mode section), while the most significant bit TxI.2 is irrelevant for
capture mode. It is recommended to keep this bit cleared (TxI.2 = ‘0’).
Note: When programmed for capture mode, the respective auxiliary timer (T2 or T4)
stops independent of its run flag T2R or T4R.
Figure 70 Auxiliary Timer of Timer Block 1 in Capture Mode
Upon a trigger (selected transition) at the corresponding input line TxIN the contents of
the core timer are loaded into the auxiliary timer register and the associated interrupt
request flag TxIR will be set.
Capture Register Tx
Core Timer T3
Up/Down
Edge
Select
T3OTL
Interrupt
Request
T3OE
T3OUT
TxIN
Input
Clock
Interrupt
Request
MCB02038
TxI
x = (2, 4)
C165H
General Purpose Timer Unit
Data Sheet 218 2001-04-19
PRELIMINARY
- EXCERPT -
Note: The direction control for T2IN and for T4IN must be set to 'Input', and the level of
the capture trigger signal should be held high or low for at least 4 fTimer (FM1 = ’1’)
cycles before it changes to ensure correct edge detection.
10.1.2 Functional Description of Timer Block 2
Timer block 2 includes the two timers T5 (referred to as the auxiliary timer) and T6
(referred to as the core timer), and the 16-bit capture/reload register CAPREL.
Note: The block 2 Timer T5 and Timer T6 can be used by Software only. There exist no
external pin for timer T5 and T6. Additional, there is no external pin connected to
register CAPREL, see also Figure 57, page 200.
The count direction (Up / Down) must be programmed via software. An overflow/
underflow of core timer T6 is indicated by the output toggle latch T6OTL whose state may
be output on line T6OFL. The auxiliary timer T6 may be reloaded with the contents of
CAPREL.
The toggle bit also supports the concatenation of T6 with auxiliary timer T5, while
concatenation of T6 with other timers is provided through line T6OFL. Triggered by an
external signal, T3IN or T3EUD, the contents of timer T5 can be captured into register
CAPREL, and T5 may optionally be cleared. Both timer T6 and T5 can count up or down,
and the current timer value can be read or modified by the CPU in the non-
bitaddressable SFRs T5 and T6.
C165H
General Purpose Timer Unit
Data Sheet 219 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 71 Structure of Timer Block 2
10.1.2.1 Core Timer T6
The operation of the core timer T6 is controlled by its bitaddressable control register
T6CON.
Timer 6 Run Bit
The timer can be started or stopped by software through bit T6R (Timer T6 Run Bit).
Setting bit T6R to ‘1’ will start the timer, clearing T6R stops the timer.
Count Direction Control
The count direction of the core timer can be controlled by software only. The count
direction can be altered by setting or clearing bit T6UD.
Note: Bit T6UDE of register T6CON must be always set to ’0’.
The count direction can be changed regardless of whether the timer is running or not.
2
n
: 1
f
hw_clk
T5
Mode
Control
GPT2 Timer T5
2
n
: 1
f
hw_clk
T6
Mode
Control
GPT2 Timer T6
GPT2 CAPREL
T6OTL
T3IN/
T3EUD
U/D
U/D
Interrupt
Request
Interrupt
Request
Interrupt
Request
T6OFL
Clear
Capture
CT3
MCB03999
Clear
C165H
General Purpose Timer Unit
Data Sheet 220 2001-04-19
PRELIMINARY
- EXCERPT -
Note: The direction control works the same for core timer T6 and for auxiliary timer T5.
Therefore the lines and bits are named Tx...
Timer 6 Overflow/Underflow Monitoring
An overflow or underflow of timer T6 will clock the toggle latch T6OTL in control register
T6CON. T6OTL can also be set or reset by software.
In addition, T6OTL can be used in conjunction with the timer over/underflows as an input
for the counter function of the auxiliary timer T5. For this purpose, an internal connection
is provided for this option.
An overflow or underflow of timer T6 can also be used to clock other timers. For this
purpose, there is the special output line T6OFL.
Timer 6 in Timer Mode
Timer mode for the core timer T6 is selected by setting bit field T6M in register T6CON
to ‘000B’. In this mode, T6 is clocked with the module clock divided by a programmable
prescaler, which is selected by bit field T6I. The input frequency fT6 for timer T6 and its
resolution rT6 are scaled linearly with lower clock frequencies fTimer, as can be seen from
the following formula:
Table 34 Core Timer T6 Count Direction Control
Bit TxUDE Bit TxUD Count Direction
0 0 Count Up
0 1 Count Down
fT6 = fTimer
4 * 2<T6I - FM2> rT6 [µs] = fTimer [MHz]
4 * 2<T6I - FM2>
C165H
General Purpose Timer Unit
Data Sheet 221 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 72 Block Diagram of Core Timer T6 in Timer Mode
10.1.2.2 Auxiliary Timer T5
The auxiliary timer T5 can be configured for timer mode with the same options for the
timer frequencies and the count signal as the core timer T6. In addition, the auxiliary
timer can be concatenated with the core timer.
The individual configuration for timer T5 is determined by its bitaddressable control
register T5CON. Note that functions which are present in both timers of timer block 2 are
controlled in the same bit positions and in the same manner in each of the specific control
registers.
Run control for auxiliary timer T5 can be handled by the associated Run Control Bit T5R
in register T5CON. Alternatively, a remote control option (T5RC = ’1’) may be enabled
to start and stop T5 via the run bit T6R of core timer T6.
Note: The auxiliary timer has no overflow/underflow toggle latch. Therefore, an output
line for Overflow/Underflow Monitoring is not provided.
Count Direction Control for Auxiliary Timer
The count direction of the auxiliary timer can be controlled in the same way as for the
core timer T6. The description and the table apply accordingly.
Timer T5 in Counter Mode
Counter mode for the auxiliary timer T5 is selected by setting bit field T5M in register
T5CON to ‘001B’. In counter mode, timer T5 can be clocked by a transition of timer T6’s
output signal T6OFL only.
Core Timer Tx
TxOTL
Interrupt
Request
TxR
2
n
: 1
Txl
Up/
Down
TxUDE
MCB02028
f
hw_clk
TxUD
x = 6
C165H
General Purpose Timer Unit
Data Sheet 222 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 73 Block Diagram of Auxiliary Timer T5 in Counter Mode
The event causing an increment or decrement of the timer can be a positive, a negative,
or both a positive and a negative transition at signal T6OFL (toggle latch T6OTL).
Bit field T5P in control register T5CON selects the triggering transition (see table below).
Note: Only state transitions of T6OTL which are caused by the overflows/underflows of
T6 will trigger the counter function of T5. Modifications of T6OTL via software will
NOT trigger the counter function of T5.
Table 35 Auxiliary Timer (Counter Mode) Input Edge Selection
T5P Triggering Edge for Counter Increment / Decrement
X 0 0 None. Counter T5 is disabled
0 0 1 reserved, do not use this combination
0 1 0 reserved, do not use this combination
0 1 1 reserved, do not use this combination
1 0 1 Positive transition (rising edge) of output toggle latch T6OTL
1 1 0 Negative transition (falling edge) of output toggle latch T6OTL
1 1 1 Any transition (rising or falling edge) of output toggle latch T6OTL
Auxiliary Timer Tx Interrupt
Request
TxR
Up/
Down
TxUD
TxUDE
MCB02221
Txl
T6OFL
Edge
Select
x = 5
C165H
General Purpose Timer Unit
Data Sheet 223 2001-04-19
PRELIMINARY
- EXCERPT -
10.1.2.3 Timer Concatenation
Using the toggle bit T6OTL as a clock source for the auxiliary timer in counter mode
concatenates the core timer T6 with the auxiliary timer. Depending on which transition of
T6OTL is selected to clock the auxiliary timer, this concatenation forms a 32-bit or a 33-
bit timer / counter.
l 32-bit Timer/Counter: If both a positive and a negative transition of T6OTL is used to clock the
auxiliary timer, this timer is clocked on every overflow/underflow of the core timer T6. Thus, the
two timers form a 32-bit timer.
l 33-bit Timer/Counter: If either a positive or a negative transition of T6OTL is selected to clock the
auxiliary timer, this timer is clocked on every second overflow/underflow of the core timer T6.
This configuration forms a 33-bit timer (16-bit core timer+T6OTL+16-bit auxiliary timer).
The count directions of the two concatenated timers are not required to be the same.
This offers a wide variety of different configurations.
Figure 74 Concatenation of Core Timer T6 and Auxiliary Timer T5
Core Timer T6 T6OTL
Interrupt
Request
T6R
2
n
: 1
T6l
MCB02034gpt2
f
hw_clk
Up/Down
Auxiliary Timer T5
T5R
T5l
Edge
Select
T5IR Interrupt
Request
*)
Note: Line ’*’ only affected by over/underflows of T6, but NOT by software
modifications of T6OTL.
C165H
General Purpose Timer Unit
Data Sheet 224 2001-04-19
PRELIMINARY
- EXCERPT -
Timer Block 2 Capture/Reload Register CAPREL in Reload Mode
The 16-bit capture/reload register CAPREL can be used as a reload register for the core
timer T6. This mode is selected by setting bit T6SR = ‘1’ in register T6CON. The event
causing a reload in this mode is an overflow or underflow of the core timer T6.
When timer T6 overflows from FFFFH to 0000H (when counting up) or when it underflows
from 0000H to FFFFH (when counting down), the value stored in register CAPREL is
loaded into timer T6. This will not set the interrupt request flag CRIR associated with the
CAPREL register. However, interrupt request flag T6IR will be set indicating the
overflow/underflow of T6.
Figure 75 Timer Block 2 Register CAPREL in Reload Mode
10.1.3 GPT Register Set
All GPT12 related registers are summarized in the overview table below.
Table 36 GPT Register Overview
Name Description Address Reset Value
GPTCLC GPT Clock Control Register FE4CH0000H
T2CON Timer 2 Function Control Register FF40H0000H
T3CON Timer 3 Function Control Register FF42H0000H
T4CON Timer 4 Function Control Register FF44H0000H
T5CON Timer 5 Function Control Register FF46H0000H
T6CON Timer 6 Function Control Register FF48H0000H
T2 GPT1 Timer 2 Register FE40H0000H
Core Timer T6
Up/Down
Interrupt
Request
Input
Clock
MCB02045
T6OTL
T6SR
CAPREL Register
T6OFL
C165H
General Purpose Timer Unit
Data Sheet 225 2001-04-19
PRELIMINARY
- EXCERPT -
GPT Clock Control Register
GPTCLC (FE4CH) Reset Value: 0000H
T3 GPT1 Timer 3 Register FE42H0000H
T4 GPT1 Timer 4 Register FE44H0000H
T5 GPT2 Timer 5 Register FE46H0000H
T6 GPT2 Timer 6 Register FE48H0000H
CAPREL Capture Reload Register FE4AH0000H
T2IC1) GPT1 Timer 2 Interrupt Control Register FF60H0000H
T3IC1) GPT1 Timer 3 Interrupt Control Register FF62H0000H
T4IC1) GPT1 Timer 4 Interrupt Control Register FF64H0000H
T5IC1) GPT2 Timer 5 Interrupt Control Register FF66H0000H
T6IC1) GPT2 Timer 6 Interrupt Control Register FF68H0000H
CRIC1) GPT2 CAPREL Interrupt Control Register FF6AH0000H
1)For the Interrupt Control Register description, please refer to Chapter 6.2, page 98.
Bit Function
GPTDISR GPT Disable Request Bit
GPTDISR = ‘0’: GPT clock disable not requested
GPTDISR = ‘1’: GPT clock disable requested
GPTDISS GPT Disable Status Bit
GPTDISS = ‘0’: GPT clock enabled
GPTDISS = ‘1’: GPT clock disabled
SUSPEN Peripheral Suspend Enable Bit for OCDS
SUSPEN = ‘0’: Peripheral suspend disabled
SUSPEN = ‘1’: Peripheral suspend enabled
EXDISR External Disable Request
EXRDIS = ‘0’: External clock disable Request is enabled
EXRDIS = ‘1’: External clock disable Request is disabled
Table 36 GPT Register Overview (cont’d)
Name Description Address Reset Value
54321011 10 987615 14 13 12
GPT
DISR
GPT
DISS
000000
rw rrw rw
0000 00 SUS
PEN
EX
DISR
C165H
General Purpose Timer Unit
Data Sheet 226 2001-04-19
PRELIMINARY
- EXCERPT -
Function Control Registers
The operating mode of the core timer T3 is configured and controlled via its
bitaddressable control register T3CON.
T3CON
Timer 3 Control Register Reset Value: 0000H
1514131211109876543210
T3
IREN
T3
RDIR
T3CH
DIR
T3
EDG
E
FM1 T3
OTL T3OE T3
UDE T3UD T3R T3M T3I
Field Bits Type Value Description
T3I [2:0] rw Timer 3 Input Parameter Selection
Timer mode see Table 37 for encoding
Gated Timer see Table 37 for encoding
Counter mode see Table 38 for encoding
Incremental Interface mode see Table 39 for
encoding
T3M [5:3] rw
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 0 1
1 1 0
1 1 1
Timer 3 Mode Control
Timer Mode
Counter Mode
Gated Timer with Gate active low
Gated Timer with Gate active high
Reserved. Do not use this combination!
Reserved. Do not use this combination!
Incremental Interface Mode ( Rotation detection )
Incremental Interface Mode ( Edge detection )
T3R 6rw
0
1
Timer 3 Run Bit
Timer / Counter 3 stops
Timer / Counter 3 runs
T3UD 7rw
0
1
Timer 3 Up / Down Control
(when T3UDE = ’0)
Counting ’Up’
Counting ’Down’
T3UDE 8rw
0
1
Timer 3 External Up/Down Enable
Counting direction is internally controlled by SW
Counting direction is externally controlled by line
T3EUD
C165H
General Purpose Timer Unit
Data Sheet 227 2001-04-19
PRELIMINARY
- EXCERPT -
T3OE 9rw
0
1
Overflow/Underflow Output Enable
T3 overflow/underflow can not be externally
monitored
T3 overflow/underflow may be externally
monitored via T3OUT
T3OTL 10 rw
0 / 1
Timer 3 Output Toggle Latch
Toggles on each overflow / underflow of T3. Can
be set or reset by software.
FM1 11 rw
0
1
Fast Mode for Timer Block 1
The maximum input frequency
for Timer 2/3/4 is fTimer / 8.
The maximum input frequency
for Timer 2/3/4 is fTimer / 4.
T3EDGE 12 rw
0
1
Timer 3 Edge Detection
The bit is set on each successful edge detection.
The bit has to be reset by SW.
No count edge was detected
A count edge was detected
T3CHDIR 13 rw
0
1
Timer 3 Count Direction Change
The bit is set on a change of the countdirection of
timer 3. The bit has to be reset by SW.
No change in count direction was detected
A change in count direction was detected
T3RDIR 14 r
0
1
Timer 3 Rotation Direction
Timer 3 counts up.
Timer 3 counts down.
T3IREN 15 rw
0
1
Timer 3 Interrupt Enable
Interrupt generation for T3CHDIR and T3EDGE
is disabled.
Interrupt generation for T3CHDIR and T3EDGE
is enabled.
Table 37 Timer 3 Input Parameter Selection for Timer mode and Gated mode
T3I Prescaler for fTimer ( FM1 = 0 ) Prescaler for fTimer ( FM1 = 1 )
000 8 4
001 16 8
010 32 16
011 64 32
Field Bits Type Value Description
C165H
General Purpose Timer Unit
Data Sheet 228 2001-04-19
PRELIMINARY
- EXCERPT -
100 128 64
101 256 128
110 512 256
111 1014 512
Table 38 Timer 3 Input Parameter Selection for Counter mode
T3I Triggering Edge for Counter Update
000 None. Counter T3 is disabled
001 Positive transition ( raising edge ) on T3IN
010 Negative transition ( falling edge ) on T3IN
011 Any transition ( raising or falling edge ) on T3IN
1XX Reserved. Do not use this combination!
Table 39 Timer 3 Input Parameter Selection for Incremental Interface mode
T3I Triggering Edge for Counter Update
000 None. Counter T3 stops
001 Any transition ( raising or falling edge ) on T3IN
010 Any transition ( raising or falling edge ) on T3EUD
011 Any transition ( raising or falling edge ) on T3IN or T3EUD
1XX Reserved. Do not use this combination!
T2CON
Timer 2 Control Register Reset Value: 0000H
1514131211109876543210
T2
IREN
T2
RDIR
T2CH
DIR
T2
EDG
E
0T2RC
T2
UDE T2UD T2R T2M T2I
Table 37 Timer 3 Input Parameter Selection for Timer mode and Gated mode
T3I Prescaler for fTimer ( FM1 = 0 ) Prescaler for fTimer ( FM1 = 1 )
C165H
General Purpose Timer Unit
Data Sheet 229 2001-04-19
PRELIMINARY
- EXCERPT -
Field Bits Type Value Description
T2I [2:0] rw Timer 2 Input Parameter Selection
Timer mode see Table 40 for encoding
Gated Timer see Table 40 for encoding
Counter mode see Table 41 for encoding
Incremental Interface mode see Table 42 for
encoding
T2M [5:3] rw
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 0 1
1 1 0
1 1 1
Timer 2 Mode Control (Basic Operating Mode)
Timer Mode
Counter Mode
Gated Timer with Gate active low
Gated Timer with Gate active high
Reload Mode
Capture Mode
Incremental Interface Mode ( Rotation detection)
Incermental Interface Mode ( Edge detection )
T2R 6rw
0
1
Timer 2 Run Bit
Timer / Counter 2 stops
Timer / Counter 2 runs
T2UD 7rw
0
1
Timer 2 Up / Down Control
(when T2UDE = ’0)
Counting ’Up’
Counting ’Down’
T2UDE 8rw
0
1
Timer 2 External Up/Down Enable
Counting direction is internally controlled by SW
Counting direction is externally controlled by line
T2EUD.
Note: Pin P3.5 connected to T2EUD is also
connected to T4IN and to T3EUD.
T2RC 9rw
0
1
Timer 2 Remote Control
Timer / Counter 2 is controlled by
its own run bit T2R
Timer / Counter 2 is controlled by
the run bit of core timer 3
0[11:10] r reserved for future use; reading returns 0;
writing to these bit positions has no effect.
T2EDGE 12 rw
0
1
Timer 2 Edge Detection
The bit is set on each successful edge detection.
The bit has to be reset by SW.
No count edge was detected
A count edge was detected
C165H
General Purpose Timer Unit
Data Sheet 230 2001-04-19
PRELIMINARY
- EXCERPT -
T2CHDIR 13 rw
0
1
Timer 2 Count Direction Change
The bit is set on a change of the countdirection of
timer 2. The bit has to be reset by SW.
No change in count direction was detected
A change in count direction was detected
T2RDIR 14 r
0
1
Timer 2 Rotation Direction
Timer 2 counts up.
Timer 2 counts down.
T2IREN 15 rw
0
1
Timer 2 Interrupt Enable
Interrupt generation for T2CHDIR and T2EDGE
is disabled.
Interrupt generation for T2CHDIR and T2EDGE
is enabled.
Table 40 Timer 2 Input Parameter Selection for Timer mode and Gated mode
T2I Prescaler for fTimer ( FM1 = 0 ) Prescaler for fTimer ( FM1 = 1 )
000 8 4
001 16 8
010 32 16
011 64 32
100 128 64
101 256 128
110 512 256
111 1014 512
Table 41 Timer 2 Input Parameter Selection for Counter mode
T2I Triggering Edge for Counter Update
X 0 0 None. Counter T2 is disabled
0 0 1 Positive transition (rising edge) on T2IN
0 1 0 Negative transition (falling edge) on T2IN
0 1 1 Any transition (rising or falling edge) on T2IN
1 0 1 Positive transition (rising edge) of output toggle latch T3OTL
1 1 0 Negative transition (falling edge) of output toggle latch T3OTL
1 1 1 Any transition (rising or falling edge) of output toggle latch T3OTL
Field Bits Type Value Description
C165H
General Purpose Timer Unit
Data Sheet 231 2001-04-19
PRELIMINARY
- EXCERPT -
Table 42 Timer 2 Input Parameter Selection for Incremental Interface mode
T2I Triggering Edge for Counter Update
000 None. Counter T2 stops
001 Any transition ( raising or falling edge ) on T2IN
010 Any transition ( raising or falling edge ) on T2EUD
011 Any transition ( raising or falling edge ) on T2IN or T2EUD
1XX Reserved. Do not use this combination!
T4CON
Timer 4 Control Register Reset Value: 0000H
1514131211109876543210
T4
IREN
T4
RDIR
T4CH
DIR
T4
EDG
E
’0’ T4RC
’0’
(T4
UDE)
T4UD T4R T4M T4I
Field Bits Type Value Description
T4I [2:0] rw Timer 4 Input Parameter Selection
Timer mode see Table 40 for encoding
Gated Timer see Table 40 for encoding
Counter mode see Table 41 for encoding
T4M [5:3] rw
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 0 1
1 1 0
1 1 1
Timer 4 Mode Control (Basic Operating Mode)
Timer Mode
Counter Mode
Gated Timer with Gate active low
Gated Timer with Gate active high
Reload Mode
Capture Mode
Reserved. Do not use this combination.
Reserved. Do not use this combination.
T4R 6rw
0
1
Timer 4 Run Bit
Timer / Counter 4 stops
Timer / Counter 4 runs
T4UD 7rw
0
1
Timer 4 Up / Down Control
Counting ’Up’
Counting ’Down’
’0’ (T4UDE-bit) 8rw
0
Timer 4 External Up/Down Enable
This bit must be set to ’0’ signal.
C165H
General Purpose Timer Unit
Data Sheet 232 2001-04-19
PRELIMINARY
- EXCERPT -
T4RC 9rw
0
1
Timer 4 Remote Control
Timer / Counter 4 is controlled by
its own run bit T4R
Timer / Counter 4 is controlled by
the run bit of core timer 3
’0’ [11:10] r reserved for future use; reading returns 0;
writing to these bit positions has no effect.
T4EDGE 12 rw
0
1
Timer 4 Edge Detection
The bit is set on each successful edge detection.
The bit has to be reset by SW.
No count edge was detected
A count edge was detected
T4CHDIR 13 rw
0
1
Timer 4 Count Direction Change
The bit is set on a change of the countdirection of
timer 4. The bit has to be reset by SW.
No change in count direction was detected
A change in count direction was detected
T4RDIR 14 r
0
1
Timer 4 Rotation Direction
Timer 4 counts up.
Timer 4 counts down.
T4IREN 15 rw
0
1
Timer 4 Interrupt Enable
Interrupt generation for T4CHDIR and T4EDGE
is disabled.
Interrupt generation for T4CHDIR and T4EDGE
is enabled.
Table 43 Timer 4 Input Parameter Selection for Timer mode and Gated mode
T4I Prescaler for fTimer ( FM1 = 0 ) Prescaler for fTimer ( FM1 = 1 )
000 8 4
001 16 8
010 32 16
011 64 32
100 128 64
101 256 128
110 512 256
111 1014 512
Field Bits Type Value Description
C165H
General Purpose Timer Unit
Data Sheet 233 2001-04-19
PRELIMINARY
- EXCERPT -
Table 44 Timer 4 Input Parameter Selection for Counter mode
T4I Triggering Edge for Counter Update
X 0 0 None. Counter T4 is disabled
0 0 1 Positive transition (rising edge) on T4IN
0 1 0 Negative transition (falling edge) on T4IN
0 1 1 Any transition (rising or falling edge) on T4IN
1 0 1 Positive transition (rising edge) of output toggle latch T3OTL
1 1 0 Negative transition (falling edge) of output toggle latch T3OTL
1 1 1 Any transition (rising or falling edge) of output toggle latch T3OTL
T6CON
Timer 6 Control Register Reset Value: 0000H
1514131211109876543210
T6SR T6
CLR ’0’ FM2 T6
OTL
’0’
(T6
OE)
’0’
(T6
UDE)
T6UD T6R T6M T6I
Field Bits Type Value Description
T6I [2:0] rw Timer 6 Input Parameter Selection
Timer mode see Table 45 for encoding
T6M [5:3] rw
0 0 0
0 0 1
0 1 0
0 1 1
1 x x
Timer 6 Mode Control (Basic Operating
Mode)
Timer Mode
Reserved. Do not use this combination!
Reserved. Do not use this combination!
Reserved. Do not use this combination!
Reserved. Do not use this combination!
T6R 6rw
0
1
Timer 6 Run Bit
Timer / Counter 6 stops
Timer / Counter 6 runs
T6UD 7rw
0
1
Timer 6 Up / Down Control
Counting ’Up’
Counting ’Down’
’0’ (T6UDE) 8rw
0
Timer 6 External Up/Down Enable
This bit must be set to ’0’ signal
’0’ (T6OE) 9rw
0
Overflow/Underflow Output Enable
This bit must be set to ’0’ signal
C165H
General Purpose Timer Unit
Data Sheet 234 2001-04-19
PRELIMINARY
- EXCERPT -
T6OTL 10 rw
0 / 1
Timer 6 Output Toggle Latch
Toggles on each overflow / underflow of T6.
Can be set or reset by software.
FM2 11 rw
0
1
Fast Mode for Timer Block 2
The maximum input frequency
for Timer 5/6 is fTimer / 4.
The maximum input frequency
for Timer 5/6 is fTimer / 2.
’0’ [13:12] r reserved for future use; reading returns 0;
writing to these bit positions has no effect.
T6CLR 14 rw
0
1
Timer 6 Clear Bit
Timer 6 is not cleared on a capture event
Timer 6 is cleared on a capture event
T6SR 15 rw
0
1
Timer 6 Reload Mode Enable
Reload from register CAPREL Disabled
Reload from register CAPREL Enabled
Table 45 Timer 6 Input Parameter Selection for Timer mode and Gated mode
T6I Prescaler for fTimer ( FM2 = 0 ) Prescaler for fTimer ( FM2 = 1 )
000 4 2
001 8 4
010 16 8
011 32 16
100 64 32
101 128 64
110 256 128
111 512 256
T5CON
Timer 5 Control Register Reset Value: 0000H
1514131211109876543210
T5SC T5
CLR CI CC ’1’
(CT3) T5RC
’0’
(T5
UDE)
T5UD T5R ’0’ T5M T5I
Field Bits Type Value Description
C165H
General Purpose Timer Unit
Data Sheet 235 2001-04-19
PRELIMINARY
- EXCERPT -
Field Bits Type Value Description
T5I [2:0] rw Timer 5 Input Parameter Selection
Timer mode see Table 46 for encoding
Counter mode see Table 47 for encoding
T5M [4:3] rw
0 0
0 1
1 0
1 1
Timer 5 Mode Control (Basic Operating Mode)
Timer Mode
Counter Mode
Reserved. Do not use this configuration
Reserved. Do not use this configuration
’0’ 5r reserved for future use; reading returns 0;
writing to these bit positions has no effect.
T5R 6rw
0
1
Timer 5 Run Bit
Timer / Counter 5 stops
Timer / Counter 5 runs
T5UD 7rw
0
1
Timer 5 Up / Down Control
Counting ’Up’
Counting ’Down’
’0’ (T5UDE) 8rw
0
Timer 5 External Up/Down Enable
This bit must be set to ’0’ signal
T5RC 9rw
0
1
Timer 5 Remote Control
Timer / Counter x is controlled by
its own run bit T5R
Timer / Counter 5 is controlled by
the run bit of core timer 6 (T6R)
’1’ (CT3) 10 rw
0
Timer 3 Capture Trigger Enable
This bit must be set to ’1’ signal
CC 11 rw
0
1
Capture Correction
T5 is just captured
T5 is decremented by 1 before being captured
CI [13:12] rw
0 0
0 1
1 0
1 1
Register CAPREL Capture Trigger Selection
Capture disabled
Any transition on T3IN
Any transition on T3EUD
Any transition on T3IN or T3EUD
T5CLR 14 rw
0
1
Timer 5 Clear Bit
Timer 5 not cleared on a capture
Timer 5 is cleared on a capture
T5SC 15 rw
0
1
Timer 5 Capture Mode Enable
Capture into register CAPREL Disabled
Capture into register CAPREL Enabled
C165H
General Purpose Timer Unit
Data Sheet 236 2001-04-19
PRELIMINARY
- EXCERPT -
Table 46 Timer 5 Input Parameter Selection for Timer mode
T5I Prescaler for fTimer ( FM2 = 0 ) Prescaler for fTimer ( FM2 = 1 )
000 4 2
001 8 4
010 16 8
011 32 16
100 64 32
101 128 64
110 256 128
111 512 256
Table 47 Timer 5 Input Parameter Selection for Counter mode
T5I Triggering Edge for Counter Update
X 0 0 None. Counter T5 is disabled
0 0 1 Reserved, do not use this combination
0 1 0 Reserved, do not use this combination
0 1 1 Reserved, do not use this combination
1 0 1 Positive transition (rising edge) of output toggle latch T6OTL
1 1 0 Negative transition (falling edge) of output toggle latch T6OTL
1 1 1 Any transition (rising or falling edge) of output toggle latch T6OTL
T2/T3/T4/T5/T6
Timer Tx Register Reset Value: 0000H
1514131211109876543210
value
Field Bits Type Value Description
value [15:0] rw Timer Tx Register
16 bit register contains the actual timer value of
the respective Timer Tx.
C165H
General Purpose Timer Unit
Data Sheet 237 2001-04-19
PRELIMINARY
- EXCERPT -
CAPREL
GPT2 CAPREL Register Reset Value: 0000H
1514131211109876543210
value
Field Bits Type Value Description
value [15:0] rw GPT2 CAPREL Register
16 bit register contains the actual value of the
CAPREL register.
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 238 2001-04-19
PRELIMINARY
- EXCERPT -
11 Asynchronous/Synchr. Serial Interface
The Asynchronous/Synchronous Serial Interface (ASC) provides serial communication
between the C165H and other microcontrollers, microprocessors or external peripherals.
The ASC supports a certain protocol to transfer data via a serial interconnection.
11.1 Functional Description
The ASC supports full-duplex asynchronous communication up to 2.25 MBaud and half-
duplex synchronous communication up to 4.5 MBaud (@ 36 MHz CPU clock which is
equal to the ASC module clock). In synchronous mode, data are transmitted or received
synchronous to a shift clock which is generated by the microcontroller. In asynchronous
mode, 8- or 9-bit data transfer, parity generation, and the number of stop bits can be
selected.
11.1.1 Features
• Full duplex asynchronous operating modes
– 8- or 9-bit data frames, LSB first
– Parity bit generation/checking
– One or two stop bits
– Baudrate from 2.25 MBaud to 0.5364 Baud (@ 36 MHz module clock = CPU clock)
– Multiprocessor mode for automatic address/data byte detection
– Loop-back capability
– Support for IrDA data transmission/reception up to max. 115.2 kBaud
• Autobaud detection unit for asynchronous operating modes
– Detection of standard baudrates
1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200, 230400 Baud
– Detection of non-standard baudrates
– Detection of asynchronous modes
7 bit, even parity; 7 bit, odd parity;
8 bit, even parity; 8 bit, odd parity; 8 bit, no parity
– Automatic initialization of control bits and baudrate generator after detection
– Detection of a serial two-byte ASCII character frame
• Recently introduced fractional divider
– The fractional divider drastically improves the accuracy of the adjustment for
baudrates
– Standard Baud Rates generation with very small deviation (230.4 kBaud < 0.01%,
460.8 kBaud < 0.15 %, 691.2 kBaud < 0.04 %, 921.6 kBaud < 0.15 % ) @ 36 MHz
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 239 2001-04-19
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- EXCERPT -
• Half-duplex 8-bit synchronous operating mode
– Baudrate from 4.5 MBaud to 366.21 Baud (@ 36 MHz module clock = CPU clock)
• Double buffered transmitter/receiver
• Interrupt generation
– on a transmitter buffer empty condition
– on a transmit last bit of a frame condition
– on a receiver buffer full condition
– on an error condition (frame, parity, overrun error)
– on the start and the end of a autobaud detection
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 240 2001-04-19
PRELIMINARY
- EXCERPT -
11.1.2 Overview
Figure 76 shows a block diagram of the ASC with its operating modes
(asynchronous and synchronous modes.).
Figure 76 Block Diagram of the ASC
fMOD Baudrate
Timer
Serial Port
Control
Receive / Transmit
Buffers and
Shift Registers
RXDO
TXD
Synchronous
Mode
Shift Clock
fMOD Baudrate
Timer
Serial Port
Control
Receive / Transmit
Buffers and
Shift Registers
IrDA
Coding
Mux
IrDA
Decoding
Mux
RXD TXD
Prescaler /
Fractional
Divider
Asynchronous
Mode
fDIV
Autobaud
Detection
÷ 2
or
÷ 3
RXDI
Note: RXDI and RXDO are concatenated
in the port logic to pin RXD.
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 241 2001-04-19
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- EXCERPT -
11.1.3 Register Description
The ASC registers can be basically divided into four types of registers as shown in
Figure 77.
Figure 77 SFRs associated with ASC
Table 48 ASC Register Summary
Name Address Reset Value Type 1) Description
S0CLC FFBAH0000Hrw / r ASC Clock Control Register
S0CON FFB0H0000Hrwh Control Register
ABS0CON FEF8H0000Hrwh Autobaud Control Register
ABSTAT FEFEH0000Hrwh Autobaud Status Register
S0BG FEB4H0000Hrw Baudrate Timer Reload Register
S0FDV FEB6H0000Hrw Fractional Divider Register
S0PMW FEAAH0000Hrw IrDA Pulse Mode and Width Register
S0TBUF FEB0H0000Hrw Transmit Buffer Register
S0RBUF FEB2H0000Hr Receive Buffer Register
S0CLC Clock Control Register
S0ID Identification Register
S0CON Control Register
ABS0CONAutobaud Control Register
ABSTAT Autobaud Status Register
S0TIC ASC Transmit Interrupt Control Register
S0RIC ASC Receive Interrupt Control Register
S0BG Baudrate Timer Reload Register
S0FDV Fractional Divider Register
S0PMW IrDA Pulse Mode and Width Register
S0TBUF Transmit Buffer Register
S0RBUF Receive Buffer Register (read only)
S0EIC ASC Error Interrupt Control Register
S0TBIC ASC Transmit Buffer Interrupt Control Register
Data RegistersControl Register
S0CON S0TBUF
S0RBUF
S0BG
S0FDV
S0PMW
S0CLC
System Registers
ABS0CON
ABSTAT
Interrupt Control
S0TIC
S0RIC
S0EIC
S0TBIC
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 242 2001-04-19
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ASC Clock Control Register
S0CLC (FFBAH) Reset Value: 0000H
The serial operating modes of the ASC module are controlled by its control register
S0CON. This register contains control bits for mode and error check selection, and
status flags for error identification.
S0TIC FF6CH0000Hrw Serial Channel 0 Transmit Interrupt
Control Register
S0RIC FF6EH0000Hrw Serial Channel 0 Receive Interrupt
Control Register
S0EIC FF70H0000Hrw Serial Channel 0 Error Interrupt
Control Register
S0TBIC F19CH0000Hrw Serial Channel 0 Transmit Buffer IC
Register
1) r: read only; w: write only; rw: read- and writeable; rwh: like rw, but SFR/bit is also affected by hardware.
Bit Function
S0DISR ASC Disable Request Bit
S0DISR = ‘0’: ASC clock disable not requested
S0DISR = ‘1’: ASC clock disable requested
S0DISS ASC Disable Status Bit
S0DISS = ‘0’: ASC clock enabled
S0DISS = ‘1’: ASC clock disabled
SUSPEN Peripheral Suspend Enable Bit for OCDS
SUSPEN = ‘0’: Peripheral suspend disabled
SUSPEN = ‘1’: Peripheral suspend enabled
EXDISR External Disable Request
EXRDIS = ‘0’: External clock disable Request is enabled
EXRDIS = ‘1’: External clock disable Request is disabled
Table 48 ASC Register Summary (cont’d)
Name Address Reset Value Type 1) Description
54321011 10 987615 14 13 12
S0
DISR
S0
DISS
000000
rw rrw rw
0000 00 SUS
PEN
EX
DISR
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 243 2001-04-19
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S0CON
Control Register
1514131211109876543210
R LB BRS ODD FDE OE FE PE OEN FEN PEN/
RXDI REN STP M
Field Bits Type Value Description
M2-0 rwh
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 0 1
1 1 0
1 1 1
Mode Selection
8-bit data synchronous operation
8-bit data async. operation
IrDA mode, 8-bit data async. operation
7-bit data + parity async. operation
9-bit data async. operation
8-bit data + wake up bit async. operation
Reserved. Do not use this combination!
8-bit data + parity async. operation
Bits are set/cleared by hardware after a
successfull autobaud detection operation.
Note: In synchronous operation (M=’000’), the
Fractional Divider is always disabled.
STP 3rw
0
1
Number of Stop Bit Selection
One stop bit
Two stop bits
REN 4rwh
0
1
Receiver Enable Control
Receiver diabled
Receiver enabled
Bit can be affected during autobaud detection
operation when bit ABEN_AUREN is set.
Bit is reset by hardware after reception of byte in
synchronous mode.
PEN
RXDI
5rw
0
1
0
1
Parity Check Enable /
IrDA Input Inverter Enable
All asynchronous modes without IrDA mode:
Ignore parity
Check parity
Only in IrDA mode (M=010):
RXD input is not inverted
RXD input is inverted
FEN 6rw
0
1
Framing Check Enable (async. modes only)
Ignore framing errors
Check framing errors
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 244 2001-04-19
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Note: Serial data transmission or reception is only possible when the run bit S0CON.R
is set to ‘1’. Otherwise the serial interface is idle.
Do not program the mode control field S0CON.M to one of the reserved
combinations to avoid unpredictable behaviour of the serial interface.
OEN 7rw
0
1
Overrun Check Enable
Ignore overrun errors
Check overrun errors
PE 8rwh Parity Error Flag
Set by hardware on a parity error (PEN=’1’).
Must be reset by software.
FE 9rwh Framing Error Flag
Set by hardware on a framing error (FEN=’1’).
Must be reset by software.
OE 10 rwh Overrun Error Flag
Set by hardware on an overrun error (OEN=’1’).
Must be reset by software.
FDE 11 rw
0
1
Fractional Divider Enable
Fractional divider disabled
Fractional divider is enabled and used as
prescaler for baudrate timer (bit BRS is don’t
care)
ODD 12 rwh
0
1
Parity Selection
Even parity selected (parity bit set on odd
number of ‘1’s in data)
Odd parity selected (parity bit set on even
number of ‘1’s in data)
Bit is be set/cleared by hardware after a
successfull autobaud detection operation.
BRS 13 rw
0
1
Baudrate Selection
Baudrate timer prescaler divide-by-2 selected
Baudrate timer prescaler divide-by-3 selected
BRS is don’t care if FDE=1 (fractional divider
enabled)
LB 14 rw
0
1
Loopback Mode Enable
Loopback mode disabled
Loopback mode enabled
R15 rw
0
1
Baudrate Generator Run Control
Baudrate generator disabled (ASC_P inactive)
Baudrate generator enabled
BG should only be written if R=’0’.
Field Bits Type Value Description
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 245 2001-04-19
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- EXCERPT -
The autobaud control register ABS0CON of the ASC module is used to control the
autobaud detection operation. It contains its general enable bit, the interrupt enable
control bits, and data path control bits.
ABS0CON
Autobaud Control Register
1514131211109876543210
0000
RX
INV
TX
INV ABEM 000
FC
DET
EN
AB
DET
EN
ABST
EN
AUR
EN
AB
EN
Field Bits Type Value Description
ABEN 0rwh
0
1
Autobaud Detection Enable
Autobaud detection is disabled
Autobaud detection is enabled
ABEN is reset by hardware after a successful
autobaud detection; (with the stop bit detection of
the second character). Resetting ABEN by
software if it was set aborts the autobaud
detection.
AUREN 1rw
0
1
Automatic Autobaud Control of CON_REN
CON_REN is not affected during autobaud
detection
CON_REN is cleared (receiver disabled) when
ABEN and AUREN are set together. CON_REN
is set (receiver enabled) after a successful
autobaud detection (with the stop bit detection of
the second character).
ABSTEN 2rw
0
1
Start of Autobaud Detection Interrupt Enable
Start of autobaud detection interrupt disabled
Start of autobaud detection interrupt enabled
ABDETEN 3rw
0
1
Autobaud Detection Interrupt Enable
Autobaud detection interrupt disabled
Autobaud detection interrupt enabled
FCDETEN 4rw
0
1
First Character of Two-Byte Frame Detected
Enable
Autobaud detection interrupt ABDETIR becomes
active after the two-byte frame recognition
Autobaud detection interrupt ABDETIR becomes
active after detection of the first and second byte
of the two-byte frame.
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 246 2001-04-19
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The autobaud status register ABSTAT of the ASC module indicates the status of the
autobaud detection operation.
ABEM 8-9 rw
0 0
0 1
1 0
1 1
Autobaud Echo Mode Enable
In echo mode the serial data at RXD is switched
to TXD output.
Echo mode disabled
Echo mode is enabled during autobaud detection
Echo mode is always enabled
reserved;
TXINV 10 rw
0
1
Transmit Inverter Enable
Transmit inverter disabled
Transmit inverter enabled
RXINV 11 rw
0
1
Receive Inverter Enable
Receive inverter disabled
Receive inverter enabled
–7-5,
15-12
0allreserved
ABSTAT
Autobaud Status Register
1514131211109876543210
00000000000
DET
WAIT
SCC
DET
SCS
DET
FCC
DET
FCS
DET
Field Bits Type Value Description
FCSDET 0rwh
0
1
First Character with Small Letter Detected
no small ’a’ character detected
small ’a’ character detected
Bit is cleared by hardware when ABCON_ABEN
is set or if FCCDET or SCSDET or SCCDET is
set. Bit can be also cleared by software.
FCCDET 1rwh
0
1
First Character with Capital Letter Detected
no capital ’A’ character detected
capital ’A’ character detected
Bit is cleared by hardware when ABCON_ABEN
is set or if FCSDET or SCSDET or SCCDET is
set. Bit can be also cleared by software.
Field Bits Type Value Description
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 247 2001-04-19
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- EXCERPT -
Note: SCSDET or SCCDET are set when the second character has been recognized.
CON_ABEN is reset and ABDETIR set after SCSDET or SCCDET have seen set.
SCSDET 2rwh
0
1
Second Character with Small Letter Detected
no small ’t’ character detected
small ’t’ character detected
Bit is cleared by hardware when ABCON_ABEN
is set or if FCSDET or FCCDET or SCCDET is
set. Bit can be also cleared by software.
SCCDET 3rwh
0
1
Second Character with Capital Letter
Detected
no capital ’T’ character detected
capital ’T’ character detected
Bit is cleared by hardware when ABCON_ABEN
is set or if FCSDET or FCCDET or SCSDET is
set. Bit can be also cleared by software.
DETWAIT 4rwh
0
1
Autobaud Detection is Waiting
Either character ’a’, ’A’, ’t’, or ’T’ has been
detected.
The autobaud detection unit waits for the first ’a’
or ’A’
Bit is cleared when either FCSDET or FCCDET
is set (’a’ or ’A’ detected). Bit can be also cleared
by software. DETWAIT is set by hardware when
ABCON_ABEN is set.
–15-5 0 all reserved
Field Bits Type Value Description
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 248 2001-04-19
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- EXCERPT -
The baudrate timer reload register S0BG of the ASC module contains the 13-bit reload
value for the baudrate timer in asynchronous and sychronous mode.
The fractional divider register S0FDV of the ASC module contains the 9-bit divider value
for the fractional divider (asynchronous mode only). It is also used for reference clock
generation of the autobaud detection unit.
S0BG
Baudrate Timer/Reload Register
1514131211109876543210
0 0 0 BR_VALUE
Field Bits Type Value Description
BR_VALUE 12-0 rw all Baudrate Timer/Reload Register Value
Reading BG returns the 13-bit content of the
baudrate timer (bits 15....13 return 0); writing BG
loads the baudrate timer reload register (bits
15....13 are don’t care). BG should only be
written if CON_R=’0’.
–15-13 0 all reserved
S0FDV
Fractional Divider Register
1514131211109876543210
0000000 FD_VALUE
Field Bits Type Value Description
FD_VALUE 8-0 rw all Fractional Divider Register Value
FDV contains the 9-bit value n of the fractional
divider which defines the fractional divider ratio:
n/512 n=0-511). With n=0, the fractional divider
is switched off (input=output frequency,
fDIV = fMOD, see Figure 86).
–15-9 0 all reserved
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 249 2001-04-19
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- EXCERPT -
The IrDA pulse mode and width register S0PMW of the ASC module contains the 8-bit
IrDA pulse width value and the IrDA pulse width mode select bit. This register is only
required in the IrDA operating mode.
S0PMW
IrDA Pulse Mode/Width Register
1514131211109876543210
0000000IRPW PW_VALUE
Field Bits Type Value Description
PW_VALUE 7-0 rw all IrDA Pulse Width Value
PW_VALUE is the 8-bit value n, which defines
the variable pulse width of an IrDA pulse.
Depending on the ASC_P input frequency fMOD,
this value can be used to adjust the IrDA pulse
width to value which is not equal 3/16 bit time
(e.g. 1.6 µs).
IRPW 8rw
0
1
IrDA Pulse Width Mode Control
IrDA pulse width is 3/16 of the bit time
IrDA pulse width is defined by PW_VALUE
–15-9 0 all reserved
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 250 2001-04-19
PRELIMINARY
- EXCERPT -
The transmitter buffer register S0TBUF of the ASC module contains the transmit data
value in asynchronous and synchronous modes.
S0TBUF
Transmitter Buffer Register
1514131211109876543210
0000000 TD_VALUE
Field Bits Type Value Description
TD_VALUE 8-0 rw all Transmit Data Register Value
TBUF contains the data to be transmitted in
asynchronous and synchronous operating mode
of the ASC. Data transmission is double
buffered, Therefore, a new value can be written
to TBUF before the transmission of the previous
value is complete.
–15-9 0 all reserved
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 251 2001-04-19
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- EXCERPT -
The receiver buffer register S0RBUF of the ASC module contains the receive data value
in asynchronous and synchronous modes.
S0TIC SFR Reset Value: - - 00H
S0RIC SFR Reset Value: - - 00H
S0EIC SFR Reset Value: - - 00H
S0RBUF
Receive Buffer Register
1514131211109876543210
0000000 RD_VALUE
Field Bits Type Value Description
RD_VALUE 8-0 rw all Receive Data Register Value
S0RBUF contains the reveived data bits and,
depending on the selected mode, the parity bit in
asynchronous and synchronous operating mode
of the ASC.
In asynchronous operating mode with M=011 (7-
bit data + parity) the received parity bit is written
into RD7.
In asynchronous operating mode with M=111 (8-
bit data + parity) the received parity bit is written
into RD8.
–15-9 0 all reserved
S0
TIE
S0
TIR
54321011 10 987615 14 13 12
rw rw----rw rw----
GLVLILVL
S0
RIE
S0
RIR
54321011 10 987615 14 13 12
rw rw----rw rw----
GLVLILVL
S0
EIR S0
EIE
54321011 10 987615 14 13 12
rw rw----rw rw----
GLVLILVL
C165H
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Data Sheet 252 2001-04-19
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S0TBIC SFR Reset Value: - - 00H
Note: Please refer to the general Interrupt Control Register description on page 99 for
an explanation of the control fields.
11.1.4 General Operation
The ASC supports full-duplex asynchronous communication up to 2.25 MBaud and half-
duplex synchronous communication up to 4.5 MBaud (@ 36 MHz CPU clock which is
equal to the ASC module clock). In synchronous mode, data are transmitted or received
synchronous to a shift clock which is generated by the microcontroller. In asynchronous
mode, 8- or 9-bit data transfer, parity generation, and the number of stop bits can be
selected. Parity, framing, and overrun error detection is provided to increase the
reliability of data transfers. Transmission and reception of data is double-buffered. For
multiprocessor communication, a mechanism to distinguish address from data bytes is
included. Testing is supported by a loop-back option. A 13-bit baudrate timer with a
versatile input clock divider circuitry provides the ASC with the serial clock signal. In a
special asynchronous mode, the ASC supports IrDA data transmission up to 115.2
kBaud with fixed or programmable IrDA pulse width. A autobaud detection unit allows to
detect asynchronous data frames with its baudrate and mode with automatic initialization
of the baudrate generator and the mode controll bits.
A transmission is started by writing to the Transmit Buffer register S0TBUF. Only the
number of data bits which is determined by the selected operating mode will actually be
transmitted, ie. bits written to positions 9 through 15 of register S0TBUF are always
insignificant.
Data transmission is double-buffered, so a new character may be written to the transmit
buffer register, before the transmission of the previous character is complete. This allows
the transmission of characters back-to-back without gaps.
Data reception is enabled by the Receiver Enable Bit CON_REN. After reception of a
character has been completed, the received data and, if provided by the selected
operating mode, the received parity bit can be read from the (read-only) Receive Buffer
register S0RBUF. Bits in the upper half of S0RBUF which are not valid in the selected
operating mode will be read as zeros.
Data reception is double-buffered, so that reception of a second character may already
begin before the previously received character has been read out of the receive buffer
register. In all modes, receive buffer overrun error detection can be selected through bit
CON_OEN. When enabled, the overrun error status flag CON_OE and the error interrupt
request line EIR will be acitvated when the receive buffer register has not been read by
S0
EIR S0
EIE
54321011 10 987615 14 13 12
rw rw- - - - rw rw----
GLVLILVL
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 253 2001-04-19
PRELIMINARY
- EXCERPT -
the time reception of a second character is complete. The previously received character
in the receive buffer is overwritten.
The Loop-Back option (selected by bit CON_LB) allows the data currently being
transmitted to be received simultaneously in the receive buffer. This may be used to test
serial communication routines at an early stage without having to provide an external
network. In loop-back mode the alternate input/output function of port pins is not
required.
Note: Serial data transmission or reception is only possible when the Baudrate
Generator Run Bit CON_R is set to ‘1’. Otherwise the serial interface is idle.
Do not program the mode control field COM_M to one of the reserved
combinations to avoid unpredictable behaviour of the serial interface
11.1.5 Asynchronous Operation
Asynchronous mode supports full-duplex communication, where both transmitter and
receiver use the same data frame format and the same baudrate. Data is transmitted on
pin P3.10/TXD and received on pin P3.11/RXD. IrDA data transmission/reception is
supported up to 115.2 KBit/s. Figure 78 shows the block diagram of the ASC when
operating in asynchronous mode.
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 254 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 78 Asynchronous Mode of Serial Channel ASC
÷16
÷2
fMOD
R
13-Bit Reload Register
13-Bit Baudrate Timer
Fractional
Divider
MUX
FDE BRS
Serial Port Control
Shift Clock
MSTP
FE OE
PE
REN
FEN
PEN
OEN
LB
Receive Int.
Request
Transmit Int.
Request
Transmit Buffer
Int. Request
Error Int.
Request
Transmit Buffer Reg.
TBUF
Receive Shift
Register
Transmit Shift
Register
IrDA
Coding
TXD
Internal Bus
Samp-
ling
Mux
RXD
IrDA
Decoding
fDIV
fBRT
Shift Clock
fBR
Receive Buffer Reg.
RBUF
Mux
RIR
TIR
TBIR
EIR
Autobaud
Detection
ODD
÷3
ABSTIRI
ABDETIR
Autobaud
Start Int.
Autobaud
Detect Int.
1
1Mux
Mux
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 255 2001-04-19
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- EXCERPT -
11.1.5.1 Asynchronous Data Frames
8-Bit Data Frames
8-bit data frames either consist of 8 data bits D7...D0 (CON_M=’001B’), or of 7 data bits
D6...D0 plus an automatically generated parity bit (CON_M=’011B’). Parity may be odd
or even, depending on bit CON_ODD. An even parity bit will be set, if the modulo-2-sum
of the 7 data bits is ‘1’. An odd parity bit will be cleared in this case. Parity checking is
enabled via bit CON_PEN (always OFF in 8-bit data mode). The parity error flag
CON_PE will be set along with the error interrupt request flag, if a wrong parity bit is
received. The parity bit itself will be stored in bit RBUF.7.
Figure 79 Asynchronous 8-Bit Frames
9-Bit Data Frames
9-bit data frames either consist of 9 data bits D8...D0 (CON_M=’100B’), of 8 data bits
D7...D0 plus an automatically generated parity bit (CON_M=’111B’) or of 8 data bits
D7...D0 plus wake-up bit (CON_M=’101B’). Parity may be odd or even, depending on bit
CON_ODD. An even parity bit will be set, if the modulo-2-sum of the 8 data bits is ‘1’. An
odd parity bit will be cleared in this case. Parity checking is enabled via bit CON_PEN
(always OFF in 9-bit data and wake-up mode). The parity error flag CON_PE will be set
along with the error interrupt request flag, if a wrong parity bit is received. The parity bit
itself will be stored in bit RBUF.8.
D7
Parit
D0
LSB D1 D2 D3 D4 D5 D6
D6
Start
Bit
8 Data Bits
10-/11-Bit UART Frame
(1st)
Stop
Bit
0
1 1
(2nd)
Stop
Bit
CON_M=001B
D0
LSB D1 D2 D3 D4 D5
Start
Bit
7 Data Bits
10-/11-Bit UART Frame
(1st)
Stop
Bit
0
1 1
(2nd)
Stop
Bit
CON_M=011B
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 256 2001-04-19
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Figure 80 Asynchronous 9-Bit Frames
In wake-up mode received frames are only transferred to the receive buffer register, if
the 9th bit (the wake-up bit) is ‘1’. If this bit is ‘0’, no receive interrupt request will be
activated and no data will be transferred.
This feature may be used to control communication in multi-processor system:
When the master processor wants to transmit a block of data to one of several slaves, it
first sends out an address byte which identifies the target slave. An address byte differs
from a data byte in that the additional 9th bit is a '1' for an address byte and a '0' for a
data byte, so no slave will be interrupted by a data 'byte'. An address 'byte' will interrupt
all slaves (operating in 8-bit data + wake-up bit mode), so each slave can examine the 8
LSBs of the received character (the address). The addressed slave will switch to 9-bit
data mode (eg. by clearing bit CON_M.0), which enables it to also receive the data bytes
that will be coming (having the wake-up bit cleared). The slaves that were not being
addressed remain in 8-bit data + wake-up bit mode, ignoring the following data bytes
IrDA Frames
The modulation schemes of IrDA is based on standard asynchronous data transmission
frames. The asynchronous data format in IrDA mode (CON_M=010B) is defined as
follows :
1 start bit / 8 data bits / 1 stop bit
The coding/decoding of/to the asynchronous data frames is shown in Figure 81. In
general, during the IrDA transmissions UART frames are encoded into IR frames and
vice cersa. A low level on the IR frame indicates a “LED off“ state. A high level on the IR
frame indicates a “LED on“ state.
For a “0“ bit in the UART frame a high pulse is generated. For a “1“ bit in the UART frame
no pulse is generated. The high pulse starts in the middle of a bit cell and has a fixed
width of 3/16 of the bit time. The ASC also allows to program the length of the IrDA high
Bit 9D7
D0
LSB D1 D2 D3 D4 D5 D6
Start
Bit
9 Data Bits
11-/12-Bit UART Frame
(1st)
Stop
Bit
0
1 1
(2nd)
Stop
Bit
CON_M=100B : Bit 9 = Data Bit D8
CON_M=101B : Bit 9 = Wake-up Bit
CON_M=111B : Bit 9 = Parity Bit
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 257 2001-04-19
PRELIMINARY
- EXCERPT -
pulse. Further, the polarity of the received IrDA pulse cane be inverted in IrAD mode.
Figure 81 shows the non-inverted IrDA pulse scheme.
Figure 81 IrDA Frame Encoding/Decoding
11.1.5.2 Asynchronous Transmission
Asynchronous transmission begins at the next overflow of the divide-by-16 baudrate
timer (transition of the baudrate clock fBR), if bit S0CON.R is set and data has been
loaded into S0TBUF. The transmitted data frame consists of three basic elements:
– the start bit
– the data field (8 or 9 bits, LSB first, including a parity bit, if selected)
– the delimiter (1 or 2 stop bits)
Data transmission is double buffered. When the transmitter is idle, the transmit data
loaded into register S0TBUF is immediately moved to the transmit shift register thus
freeing S0TBUF for the next data to be sent. This is indicated by the transmit buffer
interrupt request line TBIR being activated. S0TBUF may now be loaded with the next
data, while transmission of the previous one is still going on.
The transmit interrupt request line TIR will be activated before the last bit of a frame is
transmitted, ie. before the first or the second stop bit is shifted out of the transmit shift
register.
The transmitter output pin P3.10/TXD must be configured for alternate data output’.
11.1.5.3 Asynchronous Reception
Asynchronous reception is initiated by a falling edge (1-to-0 transition) on pin P3.11/
RXD, provided that bits CON_R and CON_REN are set. The receive data input pin
Start
Bit
Start
Bit 8 Data Bits
UART Frame
Stop
Bit
Bit
Time
8 Data Bits
IR Frame
Stop
Bit
010 00 01111
010 00 01111
Pulse Width =
3/16 Bit Time
(or variable length)
1/2 Bit Time
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 258 2001-04-19
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P3.11/RXD is sampled at 16 times the rate of the selected baudrate. A majority decision
of the 7th, 8th and 9th sample determines the effective bit value. This avoids erroneous
results that may be caused by noise.
If the detected value is not a '0' when the start bit is sampled, the receive circuit is reset
and waits for the next 1-to-0 transition at pin P3.11/RXD. If the start bit proves valid, the
receive circuit continues sampling and shifts the incoming data frame into the receive
shift register.
When the last stop bit has been received, the content of the receive shift register is
transferred to the receive data buffer register S0RBUF. Simultaneously, the receive
interrupt request line RIR is activated after the 9th sample in the last stop bit time slot (as
programmed), regardless whether valid stop bits have been received or not. The receive
circuit then waits for the next start bit (1-to-0 transition) at the receive data input pin.
The receiver input pin P3.11/RXD must be configured for input.
Asynchronous reception is stopped by clearing bit CON_REN. A currently received
frame is completed including the generation of the receive interrupt request and an error
interrupt request, if appropriate. Start bits that follow this frame will not be recognized.
Note: In wake-up mode received frames are only transferred to the receive buffer
register, if the 9th bit (the wake-up bit) is ‘1’. If this bit is ‘0’, no receive interrupt
request will be activated and no data will be transferred.
11.1.5.4 IrDA Mode
The duration of the IrDA pulse is normally 3/16 of a bit period. The IrDA standard also
allows the pulse duration being independent of the baudrate or bit period. In this case
the transmitted pulse has always the width corresponding to the 3/16 pulse width at
115.2 kBaud which is 1.627 µs. Both, bit period dependend or fixed IrDA pulse width
generation can be selected. The IrDA pulse width mode is selected by bit PMW_IRPW.
In case of fixed IrDA pulse width generation, the lower 8 bits in register PMW are used
to adapt the IrDA pulse width to a fixed value of e.g. 1.627 µs. The fixed IrDA pulse width
is generated by a programmable timer as shown in Figure 82.
Figure 82 Fixed IrDA Pulse Generation
PMW
8-Bit Timer
fMOD
Start Timer
IrDA Pulse
tIPW
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 259 2001-04-19
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- EXCERPT -
The IrDA pulse width can be calculated according the formulas given in Table 49.
The name PMW in the formulas of Table 49 represents the content of the reload register
PMW (PW_VALUE), taken as unsigned 8-bit integer.
The content of PMW further defines the minimum IrDA pulse width (tIPW min) which is still
recognized during a receive operation as a valid IrDA pulse. This function is independent
of the selected IrDA pulse width mode (fixed or variable) which is defined by bit
PMW_IRPW. The minimum IrDA pulse width is calculated by a shift right operation of
PMW bit 7-0 by one bit divided by the module clock fMOD.
Note: If PMW_IRPW=0 (fixed IrDA pulse width), PW_VALUE must be a value which
assures that t IPW > t IPW min.
Table 50 gives two examples for typical frequencies of the C165H: 36 MHz and 24 MHz..
11.1.5.5 RXD/TXD Data Path Selection in Asynchronous Modes
The data paths for the serial input and output data of the ASC in asynchronous modes
are affected by several control bits in the registers CON and ABCON as shown in
Figure 83. The synchronous mode operation is not affected by these data path selection
capabilities.
The input signal from RXD passes an inverter which is controlled by bit ABCON_RXINV.
The output signal of this inverter is used for the autobaud detection and may bypass the
ASC logic in the echo mode (controlled by bit ABCON_ABEM). Further, two multiplexers
are in the RXD input signal path for providing the loopback mode capability (controlled
by bit CON_LB) and the IrDA receive pulse inversion capability (controlled by bit
CON_RXDI).
Table 49 Formulas for the IrDA Pulse Width Calculation
PMW PMW_IRPW Formulas
1 ... 255 0
1
Table 50 IrDA Pulse Width Adaption to 1.627 µs
fMOD PMW tIPW Error tIPW min
24 MHz 39 1.625 µs - 0.12 % 0.79 µs
36 MHz 59 1.639 µs + 0.74 % 0.81 µs
t IPW = 16 x Baudrate
3
t IPW min = fMOD
(PMW >> 1)
t IPW = fMOD
PMW
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 260 2001-04-19
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Depending on the asynchronous operating mode (controlled by bitfield CON_M), the
ASC output signal or the RXD input signal in echo mode (controlled by bit
ABCON_ABEM) is switched to the TXD output via an inverter (controlled by bit
ABCON_TXINV).
Figure 83 RXD/TXD Data Path in Asynchronous Modes (ASC)
Note: In echo mode the transmit output signal of the ASC logic is blocked by the echo
mode output multiplexer. Figure 83 also shows that it is not possible to use an
IrDA coded receiver input signal for autobaud detection.
11.1.6 Synchronous Operation
Synchronous mode supports half-duplex communication, basically for simple I/O
expansion via shift registers. Data is transmitted and received via pin RXD while pin TXD
outputs the shift clock. These signals are alternate functions of port pins P3.11 and
P3.10. Synchronous mode is selected with CON_M=’000B’.
Eight data bits are transmitted or received synchronous to a shift clock generated by the
internal baudrate generator. The shift clock is only active as long as data bits are
transmitted or received.
Note: The lines RXDI and RXDO are concatenated in the port logic to pin RXD.
RXINV
Detection
Autobaud
Asynch. Mode Logic
ASC
TXD
RXD
ABCON
CON
TXINV
ABEM
IrDA
Coding
IrDA
Decode
Mux
M
Mux
RXDI
Mux
Mux
Mux
LB
Mux
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 261 2001-04-19
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- EXCERPT -
Figure 84 Synchronous Mode of Serial Channel ASC_P
11.1.6.1 Synchronous Transmission
Synchronous transmission begins within 4 state times after data has been loaded into
S0TBUF provided that CON_R is set and CON_REN=’0’ (half-duplex, no reception).
Exception : in loopback mode (bit CON_LB set), CON_REN must be set for reception of
the transmitted byte. Data transmission is double buffered. When the transmitter is idle,
the transmit data loaded into S0TBUF is immediately moved to the transmit shift register
thus freeing S0TBUF for the next data to be sent. This is indicated by the transmit buffer
interrupt request line TBIR being activated. S0TBUF may now be loaded with the next
data, while transmission of the previous one is still going on. The data bits are
transmitted synchronous with the shift clock. After the bit time for the 8th data bit, both
TXD
÷4
fMOD
R
13-Bit Reload Register
13-Bit Baudrate Timer
Serial Port Control
Shift Clock
M=000B
OE
REN
OEN
LB
Transmit Buffer Reg.
TBUF
Transmit Shift
Register
Internal Bus
MUX
RXDI
fDIV
fBRT
Shift Clock
fBR
0
1
÷2
÷3
Mux
BRS
Receive Buffer Reg.
RBUF
Receive Shift
Register
Receive Int.
Request
Transmit Int.
Request
Transmit Buffer
Int. Request
Error Int.
Request
RIR
TIR
TBIR
EIR
Note: RXDI and RXDO are
port logic to pin RXD.
RXDO
concatenated in the
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 262 2001-04-19
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TXD and RXD will go high, the transmit interrupt request line TIR is activated, and serial
data transmission stops.
Pin P3.10/TXD must be configured for alternate data output in order to provide the shift
clock. Pin P3.11/RXD must also be configured for output during transmission.
11.1.6.2 Synchronous Reception
Synchronous reception is initiated by setting bit CON_REN=’1’. If bit CON_R=1, the data
applied at RXD is clocked into the receive shift register synchronous to the clock which
is output at pin TXD. After the 8th bit has been shifted in, the content of the receive shift
register is transferred to the receive data buffer RBUF, the receive interrupt request line
RIR is activated, the receiver enable bit CON_REN is reset, and serial data reception
stops.
Pin P3.10/TXD must be configured for alternate data output in order to provide the shift
clock. Pin P3.11/RXD must be configured as alternate data input.
Synchronous reception is stopped by clearing bit CON_REN. A currently received byte
is completed including the generation of the receive interrupt request and an error
interrupt request, if appropriate. Writing to the transmit buffer register while a reception
is in progress has no effect on reception and will not start a transmission.
If a previously received byte has not been read out of the receive buffer register at the
time the reception of the next byte is complete, both the error interrupt request line EIR
and the overrun error status flag CON_OE will be activated/set, provided the overrun
check has been enabled by bit CON_OEN.
11.1.6.3 Synchronous Timing
Figure 85 shows timing diagrams of the ASC synchronous mode data reception and
data transmission. In idle state the shift clock is at high level. With the beginning of a
synchronous transmission of a data byte the data is shifted out at RXD with the falling
edge of the shift clock. If a data byte is received through RXD data is latched with the
rising edge of the shift clock.
Between two consecutive receive or transmit data bytes one shift clock cycle (fBR) delay
is inserted.
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 263 2001-04-19
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Figure 85 ASC_P3 Synchronous Mode Waveforms
11.1.7 Baudrate Generation
The serial channel ASC has its own dedicated 13-bit baudrate generator with 13-bit
reload capability, allowing baudrate generation independent of the GPT timers.
The baudrate generator is clocked with a clock (fDIV) which is derived via a prescaler from
the ASC input clock fMOD, e.g. 36 MHz. The baudrate timer is counting downwards and
can be started or stopped through the baudrate generator run bit CON_R. Each
underflow of the timer provides one clock pulse to the serial channel. The timer is
reloaded with the value stored in its 13-bit reload register each time it underflows. The
resulting clock fBRT is again divided by a factor for the baudrate clock (± 16 in
asynchronous modes and ± 4 in synchronous mode). The prescaler is selected by the
bits CON_BRS and CON_FDE. In the asynchronous operating modes, additionally to
the two fixed dividers a fractional divider prescaler unit is available which allows to select
prescaler divider ratios of n/512 with n=0-511. Therefore, the baudrate of ASC is
Shift
Latch
Shift
Latch
Valid
Shift
Valid
Data n+2
Shift Clock
Transmit Data
Shift Clock
Transmit Data
Receive Data Valid
Data n
Receive/Transmit Timing
Continuous Transmit Timing
Data
Bit n
Data
Bit n+1
Data
Bit n+2
D0 D1 D2 D3 D4 D5 D6 D7 D0 D1 D2 D3
1. Byte 2. Byte
Receive Data
D0 D0 D1 D2 D3D6 D7D1 D2 D3 D4 D5
Data n+1
1. Byte 2. Byte
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 264 2001-04-19
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- EXCERPT -
determined by the module clock, the content of S0FDV, the reload value of S0BG and
the operating mode (asynchronous or synchronous).
Register S0BG is the dual-function Baudrate Generator/Reload register. Reading BG
returns the content of the timer BR_VALUE (bits 15...13 return zero), while writing to
S0BG always updates the reload register (bits 15...13 are insiginificant).
An auto-reload of the timer with the content of the reload register is performed each time
CON_BG is written to. However, if CON_R=’0’ at the time the write operation to BG is
performed, the timer will not be reloaded until the first instruction cycle after CON_R=’1’.
For a clean baudrate initialization S0BG should only be written if CON_R=’0’. If S0BG is
written with CON_R=’1’, an unpredicted behaviour of the ASC may occur during running
transmit or receive operations.
11.1.7.1 Baudrates in Asynchronous Mode
For asynchronous operation, the baudrate generator provides a clock fBRT with 16 times
the rate of the established baudrate. Every received bit is sampled at the 7th, 8th and 9th
cycle of this clock. The clock divider circuitry, which generates the input clock for the 13-
bit baudrate timer, is extended by a fracxtional divider circuitry, which allows the
adjustment of more accurate baudrates and the extension of the baudrate range.
The baudrate of the baudrate generator depends on the following input clock, bits and
register values :
– Input clock fMOD
– Selection of the baudrate timer input clock fDIV by bits CON_FDE and CON_BRS
– If bit CON_FDE=1 (fractional divider) : value of register CON_FDV
– value of the 13-bit reload register S0BG
The output clock of the baudrate timer with the reload register is the sample clock in the
asynchronous modes of the ASC. For baudrate calculations, this baudrate clock fBR is
derived from the sample clock fDIV by a division by 16.
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 265 2001-04-19
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Figure 86 ASC Baudrate Generator Circuitry in Asynchronous Modes
Using the fixed Input Clock Divider
The baudrate for asynchronous operation of serial channel ASC when using the fixed
input clock divider ratios (CON_FDE=0) and the required reload value for a given
baudrate can be determined by the following formulas :
Table 51 Asynchronous Baudrate Formulas using the Fixed Input Clock
Dividers
FDE BRS BG Formula
0 0 0 ... 8191
1
÷16
÷2
fMOD
Baud
Rate
Clock
Sample
Clock
R
13-Bit Reload Register
13-Bit Baudrate Timer
÷3
Fractional
Divider
Mux
FDE
BRS
FDE BRS Selected Divider
00 ÷ 2
01 ÷ 3
1 X Fractional Divider
fDIV
fBRT
fBR
32 x (BG+1)
Baudrate = fMOD
32 x Baudrate
fMOD
BG = - 1
48 x (BG+1)
Baudrate = fMOD
48 x Baudrate
fMOD
BG = - 1
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 266 2001-04-19
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BG represents the contents of the reload register S0BG (BR_VALUE), taken as
unsigned 13-bit integer.
The maximum baudrate that can be achieved for the asynchronous modes when using
the two fixed clock dividers and a module clock of 36 MHz is 1.125 MBaud. Table 52
below lists various commonly used baudrates together with the required reload values
and the deviation errors compared to the intended baudrate.
Note: CON_FDE must be 0 to achieve the baudrates in the table above. The deviation
errors given in the table above are rounded. Using a baudrate crystal will provide
correct baudrates without deviation errors.
Using the Fractional Divider
When the fractional divider is selected, the input clock fDIV for the baudrate timer is
derived from the module clock fMOD by a programmable divider. If CON_FDE=1, the
fractional divider is activated, It divides fMOD by a fraction of n/512 for any value of n from
0 to 511. If n=0, the divider ratio is 1 which means that fDIV=fMOD. In general, the fractional
divider allows to program the baudrrate with a much better accuracy than with the two
fixed prescaler divider stages.
Table 52 Typical Asynchronous Baudrates using the Fixed Input Clock
Dividers
Baudrate BRS = ‘0’, fMOD = 36 MHz BRS = ‘1’, fMOD = 36 MHz
Deviation Error Reload Value Deviation Error Reload Value
1.125 MBaud --- 0000H--- ---
750.0 kBaud --- --- --- 0000H
19.2 kBaud - 0.69 % 003AH+ 0.16 % 0026H
9600 Baud + 0.16 % 0074H+ 0.16 % 004DH
4800 Baud + 0.16 % 00E9H+ 0.16 % 009BH
2400 Baud + 0.16 % 01D3H+ 0.16 % 0137H
1200 Baud + 0.05 % 03A8H +/- 0.0 % 0270H
Table 53 Asynchronous Baudrate Formulas using the Fractional Input Clock
Divider
FDE BRS BG FDV Formula
1 X 1 ... 8191 1 ... 511
0
FDV
16 x (BG+1)
Baudrate = fMOD
512 x
16 x (BG+1)
Baudrate = fMOD
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 267 2001-04-19
PRELIMINARY
- EXCERPT -
BG represents the content of the reload register S0BG (BR_VALUE), taken as unsigned
13-bit integer. FDV represents the content of the fractional divider register S0FDV
(FD_VALUE) taken as unsigned 9-bit integer. For example, typical asynchronous
baudrates are shown in Table 54.
Using the fractional divider and a module clock of 36 MHz (equal to the C165H CPU
clock) the available baudrate range is 2.25 MBaud down to 0.5364 Baud.
.
Note: The ApNote AP2423 provides a program ’ASC.EXE’ which allows to calculate
values for the S0FDV and S0BG registers depending on fMOD, the requested
baudrate, and the maximum deviation. Please contact your Infineon Technologies
representative.
11.1.7.2 Baudrates in Synchronous Mode
For synchronous operation, the baudrate generator provides a clock with 4 times the rate
of the established baudrate.(see Figure 87).
Table 54 Typical Asynchronous Baudrates using the Fractional Input Clock
Divider
fMOD Desired
Baudrate
BG FDV Resulting
Baudrate
Deviation
36 MHz max. Baudrate 0 0 2.25 MBaud 0 %
230.4 kBaud 6 367 230.399 kBaud < 0.01 %
115.2 kBaud 13 367 115.199 kBaud < 0.01 %
57.6 kBaud 27 367 57.5997 kBaud < 0.01 %
38.4 kBaud 41 367 38.3998 kBaud < 0.01 %
19.2 kBaud 83 367 19.1999 kBaud < 0.01 %
min. Baudrate 8191 1 0.53644 Baud 0 %
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 268 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 87 ASC Baudrate Generator Circuitry in Synchronous Mode
The baudrate for synchronous operation of serial channel ASC can be determined by the
formulas as shown in Table 55.
BG represents the content of the reload register S0BR (BR_VALUE), taken as unsigned
13-bit integers.
The maximum baudrate that can be achieved in synchronous mode when using a
module clock of 36 MHz is 4.5 MBaud.
Table 55 Synchronous Baudrate Formulas
BRS BG Formula
0 0 ... 8191
1
÷4
÷2
fMOD Shift /
Sample
Clock
R
13-Bit Reload Register
13-Bit Baudrate Timer
Mux
BRS
fDIV
fBRT
BRS Selected Divider
0÷ 2
1÷ 3
÷3
8 x (BG+1)
Baudrate = fMOD
8 x Baudrate
fMOD
BG = - 1
12 x (BG+1)
Baudrate = fMOD
12 x Baudrate
fMOD
BG = - 1
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 269 2001-04-19
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11.1.8 Autobaud Detection
11.1.8.1 General Operation
The autobaud detection unit in the ASC provides a capability to recognize the mode and
the baudrate of an asynchronous input signal at RXD. Generally, the baudrates to be
recognized must be known by the application. With this knowledge always a set of nine
baudrates can be detected. The autobaud detection unit is not designed to calculate a
baudrate of an unknown asynchronous frame.
Figure 88 shows how the autobaud detection unit of the ASC is integrated into its
asynchronous mode configuration. The RXD data line is an input to the autobaud
detection unit. The clock fDIV which is generated by the fractional divider is used by the
autobaud detection unit as time base. After successful recognition of baudrate and
asynchronous operating mode of the RXD data input signal, bits in the S0CON register
and the value of the S0BG register in the baudrate timer are set to the appropriate
values, and the ASC can start immediately with the reception of serial input data.
Figure 88 ASC Asynchronous Mode Block Diagram
The following sequence must be generally executed to start the autobaud detection unit
for operation :
– Definition of the baudrates to be detected : standard or non-standard baudrates
– Programming of the Prescaler/Fractional Divider to select a specific value of fDIV
– Starting the Prescaler/Fractional Divider (setting CON_R)
– Preparing the interrupt system of the CPU
– Enabling the autobaud detection (setting ABCON_ EN and the interrupt enable bits in ABCON
for interrupt generation, if required)
– Polling interrupt request flag or waiting for the autobaud detection interrupt
fMOD Baudrate
Timer
Serial Port
Control
Receive / Transmit
Buffers and
Shift Registers
IrDA
Coding
Mux
IrDA
Decoding
Mux
RXD TXD
Prescaler /
Fractional
Divider
Asynchronous
Mode
fDIV
Autobaud
Detection
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 270 2001-04-19
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11.1.8.2 Serial Frames for Autobaud Detection
The autobaud detection of the ASC is based on the serial reception of a specific two-byte
serial frame. This serial frame is build up by the two ASCII bytes "at" or "AT" ("aT" or "At"
are not allowed). Both byte combinations can be detected in five types of asynchronous
frames. Figure 89 and Figure 90 show the serial frames which are detected at least.
Figure 89 Two-Byte Serial Frames with ASCII ’at’
1000011001 0010111011
stopparitystartstopparitystart
’a’ = 61H’t’ = 74H
1000011011
stopparitystart
’a’ = 61H
0010111001
stopparitystart
’t’ = 74H
8 bit, even parity
8 bit, odd parity
100001101
stopstart
’a’ = 61H
001011111
start
’t’ = 74H
100001101
stopstart
’a’ = 61H
001011101
stopstart
’t’ = 74H
8 bit, no parity
parity stopparity
7 bit, odd parity
100001111
stopstart
’a’ = 61H
001011101
start
’t’ = 74H
parity stopparity
7 bit, even parity
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 271 2001-04-19
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Figure 90 Two-Byte Serial Frames with ASCII ’AT’
1000001011 0010101001
stopparitystartstopparitystart
’A’ = 41H’T’ = 54H
1000001001
stopparitystart
’A’ = 41H
0010101011
stopparitystart
’T’ = 54H
8 bit, even parity
8 bit, odd parity
100000111
stopstart
’A’ = 41H
001010101
start
’T’ = 54H
100000101
stopstart
’A’ = 41H
001010101
stopstart
’T’ = 54H
8 bit, no parity
parity stopparity
7 bit, odd parity
100000101
stopstart
’A’ = 41H
001010111
start
’T’ = 54H
parity stopparity
7 bit, even parity
C165H
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Data Sheet 272 2001-04-19
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11.1.8.3 Baudrate Selection and Calculation
The autobaud detection requires some calculations concerning the programming of the
baudrate generator and the baudrates to be detected. Two steps must be considered :
– Defining the baudrate(s) to be detected
– Programming of the baudrate timer prescaler - setup of the clock rate of fDIV
In general, the baudrate generator of the ASC in asynchronous mode is build up by two
parts (see also Figure 86) :
– the clock prescaler part which derives fDIV from fMOD
– the baudrate timer part which generates the sample clock fBRT and the baudrate clock fBR
Prior to an autobaud detection the prescaler part has to be setup by the CPU while the
baudrate timer (register BG) is initialized with a 13-bit value (BR_VALUE) automatically
after a successfull autobaud detection. For the following calculations, the fractional
divider is used (CON_FDE = 1).
Note: It is also possible to use the fixed divide-by-2 or divide-by-3 prescaler. But the
fractional divider allows to adapt fDIV much more precise to the required value.
Standard Baudrates
For standard baudrate detection the baudrates as shown in Table 56 can be e.g.
detected. Therefore, the output frequency fDIV of the ASC baudrate generator must be
set to a frequency derived from the module clock fMOD in a way that it is equal to 11.0592
MHz. The value to be written into register FDV is the nearest integer value which is
calculated according the following formula :
Table 56 defines the nine standard baudrates (Br0 - Br8) which can be detected for
fDIV=11.0592 MHz.
Table 56 Autobaud Detection using Standard Baudrates (fDIV = 11.0592 MHz)
Baudrate
Numbering
Detectable Standard
Baudrate
Divide Factor d f BG is loaded after
detection with value
Br0 230.400 kBaud 48 2 = 002H
Br1 115.200 kBaud 96 5 = 005H
Br2 57.600 kBaud 192 11 = 00BH
Br3 38.400 kBaud 288 17 = 011H
Br4 19.200 kBaud 576 35 = 023H
FDV = 512 x 11.0592 MHz
fMOD
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Data Sheet 273 2001-04-19
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- EXCERPT -
According Table 56 a baudrate of 9600 Baud is achieved when register BG is loaded
with a value of 047H, assuming that fDIV has been set to 11.0592 MHz.
Table 56 also lists a divide factor d f which is defined with the following formula :
This divide factor df defines a fixed relationship between the prescaler output frequency
fDIV and the baudrate to be detected during the autobaud detection operation. This
means, changing fDIV results in a totally different baudrate table in means of baudrate
values. For the baudrates to be detected, the following relations are always valid :
–Br0 = f
DIV / 48D, Br1 = fDIV / 96D, ....... up to Br8 = fDIV / 9216D,
A requirement for detecting standard baudrates up to 230.400 kBaud is the fDIV minimum
value of 11.0592 MHz. With the value FD_VALUE in register FDV the fractional divider
fDIV is adapted to the module clock frequency fMOD. Table 57 defines the deviation of the
standard baudrates when using autobaud detection depending on the module clock
fMOD.
Br5 9600 Baud 1152 71 = 047H
Br6 4800 Baud 2304 143 = 08FH
Br7 2400 Baud 4608 287 = 11FH
Br8 1200 Baud 9216 575 = 23FH
Table 57 Standard Baudrates - Deviations and Errors for Autobaud Detection
fMOD FDV Error in fDIV
10 MHz not possible
12 MHz 472 + 0.03 %
13 MHz 436 + 0.1 %
16 MHz 354 + 0.03 %
18 MHz 315 + 0.14 %
18.432 MHz 307 - 0.07 %
20 MHz 283 - 0.04 %
24 MHz 236 + 0.03 %
25 MHz 226 - 0.22 %
30 MHz 189 + 0.14 %
33 MHz 172 + 0.24 %
36 MHz 157 + 0.18 %
Table 56 Autobaud Detection using Standard Baudrates (fDIV = 11.0592 MHz)
Baudrate
Numbering
Detectable Standard
Baudrate
Divide Factor d f BG is loaded after
detection with value
Baudrate = f DIV
d f
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 274 2001-04-19
PRELIMINARY
- EXCERPT -
Note: If the deviation of the baudrate after autobaud detection is to high, the baudrate
generator (fractional divider FDV and reload register BG) can be reprogrammed if
required to get a more precise baudrate with less error.
Non-Standard Baudrates
Due to the relationship between Br0 to Br8 in Table 56 concerning the divide factor df
other baudrates than the standard baudrates can be also selected. E.g. if a baudrate of
50 kBaud has to be detected, Br2 is e.g. defined as baudrate for the 50 kBaud setection.
This further results in :
–f
DIV = 50 kBaud x df@Br2 = 50 kBaud x 192 = 9.6 MHz
Therefore, depending on the module clock frequency fMOD, the value of the fractional
divider (register S0FDV must be set in this example according the formula :
Using this selection (fDIV = 9.6 MHz), the detectable baudrates start at 200 kBaud (Br0)
down to 1042 Baud (Br8). Table 58 shows the baudrate table for this example.
11.1.8.4 Overwriting Registers on Successful Autobaud Detection
With a successfull autobaud detection some bits in register S0CON and S0BG are
automatically set to a value which corresponds to the mode and baudrate of the detected
serial frame conditions (see Table 59). In control register S0CON the mode control bits
Table 58 Autobaud Detection using Non-Standard Baudrates (fDIV = 9.6 MHz)
Baudrate
Numbering
Detectable Non-Standard
Baudrates
Divide Factor d f BG is loaded after
detection with value
Br0 200.000 kBaud 48 2 = 002H
Br1 100.000 kBaud 96 5 = 005H
Br2 50 kBaud 192 11 = 00BH
Br3 33.333 kBaud 288 17 = 011H
Br4 16.667 kBaud 576 35 = 023H
Br5 8333 Baud 1152 71 = 047H
Br6 4167 Baud 2304 143 = 08FH
Br7 2083 Baud 4608 287 = 11FH
Br8 1047 Baud 9216 575 = 23FH
FDV = 512 x fDIV
fMOD with fDIV = 9.6 MHz
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 275 2001-04-19
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CON_M and the parity select bit CON_ODD are overwritten. Register S0BG is loaded
with the 13-bit reload value for the baudrate timer.
Note: The autobaud detection interrupts are described in Chapter 11.1.10.
11.1.9 Hardware Error Detection Capabilities
To improve the safety of serial data exchange, the serial channel ASC provides an error
interrupt request flag, which indicates the presence of an error, and three (selectable)
error status flags in register S0CON, which indicate which error has been detected
during reception. Upon completion of a reception, the error interrupt request line EIR will
be activated simultaneously with the receive interrupt request line RIR, if one or more of
the following conditions are met :
– the framing error detection enable bit CON_FEN is set and any of the expected stop bits is
not high, the framing error flag CON_FE is set, indicating that the error interrupt request is due
to a framing error (Asynchronous mode only).
– If the parity error detection enable bit CON_PEN is set in the modes where a parity bit is
received, and the parity check on the received data bits proves false, the parity error flag
CON_PE is set, indicating that the error interrupt request is due to a parity error
(Asynchronous mode only).
– If the overrun error detection enable bit CON_OEN is set and the last character received was
not read out of the receive buffer by software or PEC (DMA) transfer at the time the reception
of a new frame is complete, the overrun error flag CON_OE is set indicating that the error
interrupt request is due to an overrun error (Asynchronous and synchronous mode).
Table 59 Autobaud Detection Overwrite Values for the S0CON Register
Detected Parameters CON_M CON_ODD BG_BR_VALUE
Operating Mode 7 bit, even parity
7 bit, odd parity
8 bit, even parity
8 bit, odd parity
8 bit, no parity
0 1 1
0 1 1
1 1 1
1 1 1
0 0 1
0
1
0
1
0
-
Baudrate Br0
Br1
Br2
Br3
Br4
Br5
Br6
Br7
Br8
- - 2 = 002H
5 = 005H
11 = 00BH
17 = 011H
35 = 023H
71 = 047H
143 = 08FH
287 = 11FH
575 = 23FH
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 276 2001-04-19
PRELIMINARY
- EXCERPT -
11.1.10 Interrupts
Six interrupt sources are provided for serial channel ASC. Line TIR indicates a transmit
interrupt, TBIR indicates a transmit buffer interrupt, RIR indicates a receive interrupt and
EIR indicates an error interrupt of the serial channel. The autobaud detection unit
provides two additional interrupts, the ABSTIR start of autobaud operation interrupt and
the ABDETIR autobaud detected interrupt. The interrupt output lines TBIR, TIR, RIR,
EIR, ABSTIR, and ABDETIR are activated (active state) for two periods of the module
clock fMODfive.
The cause of an error interrupt request (framing, parity, overrun error) can be identified
by the error status flags FE, PE, and OE which are located in control register CON. For
the two autobaud detection interrupts register ABSTAT provides status information.
Note: In contrary to the error interrupt request line EIR, the error status flags FE/PE/OE
are not reset automatically but must be cleared by software.
For normal operation (ie. besides the error interrupt) the ASC provides three interrupt
requests to control data exchange via this serial channel:
– TBIR is activated when data is moved from TBUF to the transmit shift register.
– TIR is activated before the last bit of an asynchronous frame is transmitted, or after the last
bit of a synchronous frame has been transmitted.
– RIR is activated when the received frame is moved to RBUF.
The transmitter is serviced by two interrupt handlers. This provides advantages for the
servicing software.
For single transfers, it is sufficient to use the transmitter interrupt (TIR), which indicates
that the previously loaded data has been transmitted, except for the last bit of an
asynchronous frame.
For multiple back-to-back transfers it is necessary to load the following piece of data at
last until the time the last bit of the previous frame has been transmitted. In asynchronous
mode this leaves just one bit-time for the handler to respond to the transmitter interrupt
request, in synchronous mode it is impossible at all.
Using the transmit buffer interrupt (TBIR) to reload transmit data gives the time to
transmit a complete frame for the service routine, as TBUF may be reloaded while the
previous data is still being transmitted.
The ABSTIR start of autobaud operation interrupt is generated whenever the autobaud
detection unit is enabled (ABEN and ABDETEN and ABSTEN set), and a start bit has
been detected at RXD. In this case ABSTIR is generated during autobaud detection
whenever a start bit is detected.
The ABDETIR autobaud detected interrupt is always generated after recognition of the
second character of the two-byte frame, this means after a successful autobaud
detection. If ABCON_FCDETEN is set the ABDETIR autobaud detected interrupt is also
generated after the recognition of the first character of the two-byte frame.
C165H
Asynchronous/Synchr. Serial Interface
Data Sheet 277 2001-04-19
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- EXCERPT -
Figure 91 ASC Interrupt Generation
As shown in Figure 91, TBIR is an early trigger for the reload routine, while TIR indicates
the completed transmission. Software using handshake therefore should rely on TIR at
the end of a data block to make sure that all data has really been transmitted.
Idle Idle
Start
Start
Start
Stop
Stop
Stop
Idle Idle
Asynchronous Mode
TBIR TBIR
TIR
TBIR
TIR
RIR RIR
Synchronous Mode
TBIR
RIR
TBIR
TIR
RIR
TBIR
TIR
RIR
TIR
RIR
TIR
Idle
Start
Stop
Asynchronous Modes
ABDETIR 1)
Autobaud Detection
ABSTIR
1) only if FCDETEN=1
1. character
Start
Stop
2. character
ABDETIR
C165H
Real Time Clock (RTC)
Data Sheet 278 2001-04-19
PRELIMINARY
- EXCERPT -
12 Real Time Clock (RTC)
12.1 Introduction
The Real Time Clock (RTC) module of the C165H basically is an independent timer
chain and counts time ticks. The base frequency of the RTC can be programmed via a
reload counter. The RTC can work fully asynchronous to the system frequency and is
optimized on low power consumption.
12.1.1 Features
The RTC serves for different purposes:
– System clock to determine the current time and date
– Cyclic time based interrupt
– Alarm interrupt for wake up on a defined time
– 48-bit timer for long term measurements
12.1.2 Overview
The real time clock module provides three different types of registers: two control
registers for controlling the RTC´s functionality, three data registers for setting the clock
divider for RTC base frequency programming and for flexible interrupt generation, and
three counter registers they contain the actual time and date. The interrupts are
programmed via one interrupt sub node register.
12.2 Function Description
The RTC module consists of a chain of 2 divider blocks, the reloadable 16-bit timer T14
and the 32-bit RTC timer (accessible via registers RTCH and RTCL). Both timers count
up. Timer T14 is reloaded with the value of register T14REL on every timer T14
overflow.
The count input of the RTC module (RTC_REF_CLK) can be optional divided by a
prescaler with factor 8, see Figure 93.
The RTC module operates in two different modes, an asynchronous and a synchronous
mode. In synchronous mode the RTC module is clocked with a synchronous clock
referring to the CPU clock (RTC clock). In asynchronous mode the RTC module is
clocked with the asynchronous counting input clock (RTC_REF_CLK). The
asynchronous mode is necessary in case of a very low or disabled CPU clock (eg. sleep
mode).
The mode control (asynchronous / synchronous) of the RTC is described as follows:
• The RTC is switched to asynchronous mode if SYSCON2.RCS = '1'
• The RTC is switched to asynchronous mode if device is in sleep mode.
C165H
Real Time Clock (RTC)
Data Sheet 279 2001-04-19
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• RTC is switched to asynchronous mode if the system is not in slowdown mode and
the system clock is not locked (observe selected CLK_CFG as set during Reset).
This means that the mode is controlled by bit RCS of register SYSCON2 (see page 428)
unless the system's clock setting indicates that no or an unreliable CPU clock is
available. In the latter case, synchronous mode is not working and thus the RTC is forced
into asynchronous mode.
As long as the CPU clock is four times faster than the RTC_REF_CLK, the RTC module
can be operated in synchronous mode. Otherwise the asynchronous mode has to be
selected by software.
In asynchronous mode no writing but only asynchronous reading to the registers via the
internal bus is possible.
12.2.1 RTC Block Diagram
Figure 92 shows the RTC block diagram:
Figure 92 RTC Block Diagram
T14REL (16 bit)
T14 (16 bit)
RTC_REF_CLK
6 bit
RTCL
RTCRELL
10 bit
10 bit 6 bit
10 bit
RTCH
RTCRELH
6 bit
6 bit 10 bit
RTC_T14INT xb(3)
Interrupt Sub Node RTCISNC
RTC_INT irq(15) and
RTC3INTRTC2INTRTC1INTRTC0INT
MUX
8:1
RTCPRE
RTCR
T14_IN
altern. source fast ext. interrupt 7
C165H
Real Time Clock (RTC)
Data Sheet 280 2001-04-19
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12.2.2 RTC Control
The operating behaviour of the RTC module is controlled by the RTCCON register. The
RTC starts counting by setting the run bit RTCR. After reset the run bit is set and the RTC
automatically starts operation. The bit RTCPRE selects a prescaler which divides the
counting clock by factor 8. Activating the prescaler reduces the resolution of the reload
counter T14. If the prescaler is not activated, the RTC may be lose counting clocks on
switching from asynchronous to synchronous mode and back. This effect can be avoided
by activating the prescaler.
Setting the bits T14DEC or T14INC decrements or increments the T14 timer with the
next count event. If at the next count event a reload has to be executed, then an
increment operation is delayed until the next count event occurs. The in/decrement
function can only be used if register T14REL is not equal to FFFFH. These bits are
cleared by hardware after the decrement/increment operation.
12.2.3 System Clock Operation
A real time system clock can be maintained that represents the current time and date. If
the RTC module is not effected by a system reset, it keeps running also during idle mode
and power down mode.
The maximum resolution (minimum stepwidth) for this clock information is determined by
timer T14’s input clock. The maximum usable timespan is achieved when T14REL is
loaded with 0000H and so T14 divides by 216.
12.2.4 Cyclic Interrupt Generation
The RTC module can generate an interrupt request RTC_T14INT whenever timer T14
overflows and is reloaded. This interrupt request may eg. be used to provide a system
time tick independent of the CPU clock frequency without loading the general purpose
timers, or to wake up regularly from idle mode. The T14 overflow interrupt
(RTC_T14INT) cycle time can be adjusted via the timer T14 reload register T14REL.
This interrupt request is also ored with all other interrupts of the RTC via the RTC
interrupt sub node RTCISN.
12.2.5 Alarm Interrupt Generation
The RTC module can also provide an alarm interrupt. For an easier programming of this
interrupt, the RTCL and RTCH timer can be divided into smaller reloadable timers. Each
sub-timer can be programmed for an overflow on different time bases (e.g. second, hour,
minute, day). With each timer overflow a RTC interrupt is generated. All these RTC
interrupts are ored via the interrupt sub node RTCISNC to one interrupt request
RTC_INT. Additionally the RTC_T14INT is connected to this interrupt sub node.
C165H
Real Time Clock (RTC)
Data Sheet 281 2001-04-19
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12.2.6 48-bit Timer Operation
The concatenation of the 16-bit reload timer T14 and the 32-bit RTC timer can be
regarded as a 48-bit timer which counts with the RTC count input frequency
(RTC_REF_CLK) divided by the fixed prescaler, if the prescaler is selected. The reload
registers T14REL, RTCRELL and RTCRELH should be cleared to get a 48-bit binary
timer. However, any other reload values may be used.
The maximum usable timespan is 248 (≈1014) T14 input clocks, which equals more than
100 years (referring to a RTC count input frequency RTC_REF_CLK of 625 KHz, which
is equal to a 20 MHz Oscillator divided by 32, and an activated prescaler).
12.2.7 Defining the RTC Time Base
The count input of the RTC module (RTC_REF_CLK) is connected as shown in
Figure 93. The RTC timer base is equal to timer T14 overflow and depends on the
selectable prescaler and on the reload counter T14.
Figure 93 RTC module clocking scheme
The table below lists the RTC_T14INT interrupt period range for several RTC count input
frequencies:
Table 60 RTC Interrupt Periods
Oscillator
Frequency
Divider
Factor
RTC Input
Frequency
Prescaler
Factor
RTC_T14INT Period
Minimum Maximum
32 KHz 1 32 KHz 31.25 µs 2.048 s
1 MHz 32 312.5 KHz 8 256.0 µs 16.77 s
4 MHz 32 125 KHz 8 64.0 µs 4.194 s
RTCmoduleclk001
RTC Timer
32 bit
T14
16 bit
M
U
X
8:1
M
U
X
32:1
OSC
RTC_CLK_SEL
XTAL2
CPU_CLOCK
RTC_REF_CLK
XTAL1 RTC_T14INT
RTC_INT
RTC module (simple drawing)
C165H
Real Time Clock (RTC)
Data Sheet 282 2001-04-19
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Table 61 lists the T14 reload values for a time base of 1 s (A), 100 ms (B) and 1 ms (C)
and several RTC input frequencies:
5 MHz 32 19.531 KHz 8 51.2 µs 3.355 s
8 MHz 32 156.25 KHz 8 32.0 µs 2.097 s
10 MHz 32 312.5 KHz 8 25.6 µs 1.678 s
12 MHz 32 375 KHz 8 21.3 µs 1.398 s
16 MHz 32 500 KHz 8 16.0 µs 1.049 s
20 MHz 32 625 KHz 8 12.8 µs 0.839 s
24 MHz 32 750 KHz 8 10.67 µs 0.699 s
25 MHz 32 781.25 KHz 8 10.24 µs 0.671 s
32 MHz 32 1 MHz 8 8.0 µs 0.524 s
50 MHz 32 1.56 MHz 8 5.12 µs 0.336 s
Table 61 RTC Reload Values
RTC Input
Frequency
Reload Value A Reload Value B Reload Value C
T14REL Base T14REL Base T14REL Base
32 KHz 8300H1.000 s F380H100.0 ms FFE0H1.000 ms
312.5 KHz F0BEH0.999 s FE79H100.1 ms FFFCH1.024 ms
125 KHz C2F7H1.000 s F9E5H100.0 ms FFF0H1.024 ms
19.531 KHz B3B5H0.999 s F85FH99.9 ms FFECH1.024 ms
156.25 KHz 85EEH1.000 s F3CBH100.0 ms FFE1H0.992 ms
312.5 KHz 6769H1.000 s F0BEH99.9 ms FFD9H0.998 ms
375 KHz 48E5H1.000 s EDB0H100.0 ms FFD1H1.003 ms
500 KHz 0BDCH1.000 s E796H100.0 ms FFC1H1.008 ms
625 KHz E17BH100.0 ms FFB2H0.998 ms
750 KHz DB61H100.0 ms FFA2H1.003 ms
781.25 KHz D9DAH100.0 ms FF9EH1.004 ms
1 MHz CF2CH100.0 ms FF83H1.000 ms
1.56 MHz B3B5H99.9 ms FF3DH0.998 ms
Table 60 RTC Interrupt Periods (cont’d)
Oscillator
Frequency
Divider
Factor
RTC Input
Frequency
Prescaler
Factor
RTC_T14INT Period
Minimum Maximum
C165H
Real Time Clock (RTC)
Data Sheet 283 2001-04-19
PRELIMINARY
- EXCERPT -
12.2.8 Increased RTC Accuracy through Software Correction
The accuracy of the C165H’s RTC is determined by the oscillator frequency and by the
respective prescaling factor (excluding or including T14 and the selectable Prescaler).
The accuracy limit generated by the prescaler is due to the quantization of a binary
counter (where the average is zero), while the accuracy limit generated by the oscillator
frequency is due to the difference between ideal and real frequency (and therefore
accumulates over time). The total accuracy of the RTC can be further increased via
software for specific applications that demand a high time accuracy.
The key to the improved accuracy is the knowledge of the exact oscillator frequency. The
relation of this frequency to the expected ideal frequency is a measure for the RTC’s
deviation. The number N of cycles after which this deviation causes an error of ±1 cycle
can be easily computed. So the only action is to correct the count by ±1 after each series
of N cycles.
This correction may be applied to the RTC register as well as to T14. Also the correction
may be done cyclic, eg. within T14’s interrupt service routine, or by evaluating a formula
when the RTC registers are read (for this the respective „last“ RTC value must be
available somewhere). T14 can be adjusted by a write access or better by using the in/
decrement function provided by the RTCCON register.
Note: For the majority of applications, however, the standard accuracy provided by the
RTC’s structure will be more than sufficient.
12.2.9 Hardware dependend RTC Accuracy
The RTC has different counting accuracies, depending on the operating mode (with or
without prescaler). There is only an impact on the counting accuracy when switching the
RTC from synchronous mode to asynchronous mode and back.
.
12.2.10 Interrupt Sub Node RTCISNC
All RTC interrupts are connected to one interrupt node via an interrupt sub node. For this
interrupt sharing each interrupt source has additionally to the node enable and request
flag its own enable and request flag located in register RTCISNC. After a RTC interrupt
(RTC_INT) is arbitrated, the interrupt service routine has to check the request flags of all
enabled sources and run the respective software routine. The request flags have to be
deleted by software before leaving the interrupt service routine.
Table 62 Impact on counting accuracy
Operating mode Inaccuracy in T14 counting ticks
without prescaler +0 / -0.5
with prescaler +0 / -0
C165H
Real Time Clock (RTC)
Data Sheet 284 2001-04-19
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- EXCERPT -
The following figure shows the additional necessary differentiating circuits for the
interrupt logic:
Figure 94 Differentiating Circuits for RTC interrupt
12.2.11 RTC Disable Functionality
The Peripheral Kernel of the RTC can be disabled, if the RTC functionality is not used.
In this case only the bus interface is enabled. Disabling the RTC module reduces the
power consumption and the generated noise of the complete system. The disable
request can be set in two different ways. The bit RTCDIS (if implemented in C165H) of
the central peripheral control register SYSCON3 controls the disable request of the RTC
module. Additional the request can be set with bit RTCDISR inside the RTC Clock
Control register (RTCCLC). The central and the local disable requests are ored. Clearing
the respective disable request flag enables the RTC module again. Note that both
request flags have to be cleared for enabling the RTC module. An activated request flag
sets directly the disabling status flag RTCDISS inside the RTCCLC register and disables
the clock within the Clock Gating Module. Since the RTCCLC register is clocked with the
Diff.
Circuit
RTCISNC
&
Pulse
Generation
&
1
Note: 1)The ISR (Interrupt Service Routine) must delete the IR flag in register
RTCISNC manually. Otherwise no further interrupts can be detected.
T14
RTC0INT
Diff.
Circuit
RTC_T14INT &
Diff.
Circuit
RTC3INT
Diff.
Circuit
&
RTC1INT
Diff.
Circuit
&
RTC2INT
IE
T14
IR1)
RTC0
IE
RTC0
IR1)
RTC1
IE
RTC1
IR1)
RTC2
IE
RTC2
IR1)
RTC3
IE
RTC3
IR1)
C165H
Real Time Clock (RTC)
Data Sheet 285 2001-04-19
PRELIMINARY
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bus clock, the disabling status of the RTC can be read and the RTC can be enabled
again.
The following figure shows the disabling mechanism of the RTC module:
Figure 95 Disabling Mechanism of the RTC
In disable state no write access to RTC registers is possible. The only exeption is the
RTCCLC register.
12.2.12 Register Definition of RTC module
The following table shows the register addresses map:
Table 63 Address Map Overview
SFR Address b/p Register Name
F0C8HRTCCLC
F1CCHb RTCCON
F0D0HT14REL
F0D2HT14
F0D4HRTCL
F0D6HRTCH
F0CCHRTCRELL
F0CEHRTCRELH
F1C8Hb/p RTCISNC
RTC
DISR
RTC
DISS
01315
RTCCLC
RTC module
RTC_EX_DISR
OCDS_P_SUSPEND
SUSP
EN
2
EXR
DIS
Clock
Gating
RTC_DIS_N
C165H
Real Time Clock (RTC)
Data Sheet 286 2001-04-19
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b: bitaddressable p: bit protected
RTC Clock Control Register
RTCCLC (F0C8H) Reset Value: 0000H
Bit Function
RTCDISR RTC Disable Request Bit
RTCDISR = ‘0’: RTC clock disable not requested
RTCDISR = ‘1’: RTC clock disable requested
RTCDISS RTC Disable Status Bit
RTCDISS = ‘0’: RTC clock enabled
RTCDISS = ‘1’: RTC clock disabled
SUSPEN Peripheral Suspend Enable Bit for OCDS
SUSPEN = ‘0’: Peripheral suspend disabled
SUSPEN = ‘1’: Peripheral suspend enabled
EXDISR External Disable Request
EXRDIS = ‘0’: External clock disable Request is enabled
EXRDIS = ‘1’: External clock disable Request is disabled
54321011 10 987615 14 13 12
RTC
DISR
RTC
DISS
000000
rw rrw rw
0000 00 SUS
PEN
EX
DISR
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Real Time Clock (RTC)
Data Sheet 287 2001-04-19
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RTC Control Register
RTCCON (F1CCH) bitaddressableReset Value:0003H
Note : For compatibility reasons the bits RTCR and RTCPRE are set on asynchronous HW reset
(power on reset).
Prescaler Timer T14
Timer T14 generates the input clock for the RTC register and the periodic interrupt
T14 (F0D2H) Reset Value:0000H
Bit Function
RTCR RTC Run Bit
RTCR = ‘0’: RTC stops
RTCR = ‘1’: RTC runs
RTCPRE RTC Input Source Prescaler enable
RTCPRE = ‘0’: Input Prescaler disabled
RTCPRE = ‘1’: Input Prescaler enabled
T14DEC Decrement T14 Timer Value
Setting this bit to 1 effects a decrement of the T14 timer value. The bit is cleared
by hardware after decrementation.
T14INC Increment T14 Timer Value
Setting this bit to 1 effects an increment of the T14 timer value. The bit is cleared
by hardware after incrementation.
ACCPOS RTC register access possible
This bit indicates that a synchronous read / write access to RTC registers is
possible. The Clock Control register RTCCLC can allways be accessed.
ACCPOS = ‘0’: No write access is possible, only asynchronous reads.
ACCPOS = ‘1’: Read / Write access is possible
54321011 10 987615 14 13 12
RTC
R
RTC
PRE
00000
rw rwrw rwr
0000 0 T14
DEC
T14
INC
ACC
POS 0
54321011 10 987615 14 13 12
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Real Time Clock (RTC)
Data Sheet 288 2001-04-19
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Timer T14 Reload Register
T14REL (F0D0H) Reset Value:0000H
RTC Count Register Low Word
RTCL (F0D4H) Reset Value:0000H
RTC Count Register High Word
RTCH (F0D6H) Reset Value:0000H
RTC Reload Register Low Word
RTCRELL (F0CCH) Reset Value:0000H
RTC Reload Register High Word
RTCRELH (F0CEH) Reset Value:0000H
54321011 10 987615 14 13 12
54321011 10 987615 14 13 12
54321011 10 987615 14 13 12
54321011 10 987615 14 13 12
54321011 10 987615 14 13 12
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Real Time Clock (RTC)
Data Sheet 289 2001-04-19
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RTC Interrupt Sub Node Control
RTCISNC (F1C8H) bitaddressableReset Value:UUUUH
Note : The interrupt request flags of the RTC interrupt sub node have to be cleared by software
inside the interrupt service routine.
Bit Function
T14IE T14 Overflow Interrupt Enable Control Bit
‘0’: Interrupt request is disabled
‘1’: Interrupt request is enabled
T14IR T14 Overflow Interrupt Request Flag (bit protected)
‘0’: No request pending
‘1’: This source has raised an interrupt request
RTCxIE RTCx Interrupt Enable Control Bit
‘0’: Interrupt request is disabled
‘1’: Interrupt request is enabled
RTCxIR RTCx Interrupt Request Flag (bit protected)
‘0’: No request pending
‘1’: This source has raised an interrupt request
54321011 10 987615 14 13 12
rw rwrw
T14
IE
T14
IR
RTC
0IE
RTC
0 IR
RTC
1IE
RTC
1 IR
RTC
2IE
RTC
2 IR
000000
rw rw rwrw rw rw rw
RTC
3IE
RTC
3 IR
C165H
High-Speed Synchronous Serial Interface
Data Sheet 290 2001-04-19
PRELIMINARY
- EXCERPT -
13 High-Speed Synchronous Serial Interface
The High-Speed Synchronous Serial Interface SSC provides flexible high-speed serial
communication between the C165H and other microcontrollers, microprocessors or
external peripherals.
The SSC supports full-duplex and half-duplex synchronous communication up to 18
MBaud in SSC Master Mode and 9 MBaud in SSC Slave Mode (@ 36 MHz CPU clock).
The serial clock signal can be generated by the SSC itself (master mode) or be received
from an external master (slave mode). Data width, shift direction, clock polarity and
phase are programmable. This allows communication with SPI-compatible devices.
Transmission and reception of data is double-buffered. A 16-bit baud rate generator
provides the SSC with a separate serial clock signal.
The high-speed synchronous serial interface can be configured in a very flexible way, so
it can be used with other synchronous serial interfaces (eg. the ASC in synchronous
mode), serve for master/slave or multimaster interconnections or operate compatible
with the popular SPI interface. So it can be used to communicate with shift registers (IO
expansion), peripherals (eg. EEPROMs etc.) or other controllers (networking). The SSC
supports half-duplex and full-duplex communication. Data is transmitted or received on
pins MTSR/P3.9 (Master Transmit / Slave Receive) and MRST/P3.8 (Master Receive /
Slave Transmit). The clock signal is output or input on pin SCLK/P3.13. These pins are
alternate functions of Port 3 pins.
Figure 96 SFRs and Port Pins associated with the SSC
SCLK / P3.13
MTSR / P3.9
MRST / P3.8
SSCCLC SSC Clock Control Register
ODP3 Port 3 Open Drain Control Register
DP3 Port 3 Direction Control Register
SSCBR SSC Baud Rate Generator/Reload Register
SSCTB SSC Transmit Buffer Register
SSCTIC SSC Transmit Interrupt Control Register
P3 Port 3 Data Register
SSCCON SSC Control Register
SSCRB SSC Receive Buffer Register
SSCRIC SSC Receive Interrupt Control Register
SSCEIC SSC Error Interrupt Control Register
ODP3
Ports & Direction Control
Alternate Functions
System
Data Registers Control Registers Interrupt Control
SSCBR SSCCON SSCTIC
DP3
P3
SSCTB
SSCRB
SSCRIC
SSCEIC
SSCCLC
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High-Speed Synchronous Serial Interface
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Figure 97 Synchronous Serial Channel SSC Block Diagram
The operating mode of the serial channel SSC is controlled by its bit-addressable control
register SSCCON. This register serves for two purposes:
• during programming (SSC disabled by SSCEN=’0’) it provides access to a set of
control bits
• during operation (SSC enabled by SSCEN=’1’) it provides access to a set of status
flags
Register SSCCON is shown below in each of the two modes.
MCB01957
Receive Int. Request
Transmit Int. Request
Error Int.Request SSC Control Block
16-Bit Shift Register
Transmit Buffer
Register SSCTB Register SSCRB
Receive Buffer
Pin
Control
Status Control
Shift
Clock
Generator
Baud Rate Clock
Control
Slave Clock
Master Clock
CPU
Clock
I n t e r n a l B u s
MTSR
MRST
SCLK
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High-Speed Synchronous Serial Interface
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SSCCON (FFB2H / D9H) SFR Reset Value: 0000H
Bit Function (Programming Mode, SSCEN = ‘0’)
SSCBM SSC Data Width Selection
0 : Reserved. Do not use this combination.
1...15 : Transfer Data Width is 2...16 bit (<SSCBM>+1)
SSCHB SSC Heading Control Bit
0 : Transmit/Receive LSB First
1 : Transmit/Receive MSB First
SSCPH SSC Clock Phase Control Bit
0 : Shift transmit data on the leading clock edge, latch on trailing edge
1 : Latch receive data on leading clock edge, shift on trailing edge
SSCPO SSC Clock Polarity Control Bit
0 : Idle clock line is low, leading clock edge is low-to-high transition
1 : Idle clock line is high, leading clock edge is high-to-low transition
SSCTEN SSC Transmit Error Enable Bit
0 : Ignore transmit errors
1 : Check transmit errors
SSCREN SSC Receive Error Enable Bit
0 : Ignore receive errors
1 : Check receive errors
SSCPEN SSC Phase Error Enable Bit
0 : Ignore phase errors
1 : Check phase errors
SSCBEN SSC Baudrate Error Enable Bit
0 : Ignore baudrate errors
1 : Check baudrate errors
SSCAREN SSC Automatic Reset Enable Bit
0 : No additional action upon a baudrate error
1 : The SSC is automatically reset upon a baudrate error
SSCMS SSC Master Select Bit
0 : Slave Mode. Operate on shift clock received via SCLK.
1 : Master Mode. Generate shift clock and output it via SCLK.
SSCEN SSC Enable Bit = ‘0’
Transmission and reception disabled. Access to control bits.
54321011 10 987615 14 13 12
rw rw rwrw rw -rwrw rw -rw
-SSC
HB
SSC
PH
SSC
PO
rw rw
SSC
BEN
SSC
EN=0 SSC
MS SSC
PEN SSC
REN SSC
TEN -SSCBM
SSC
AREN
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SSCCON (FFB2H / D9H) SFR Reset Value: 0000H
Note: • The target of an access to SSCCON (control bits or flags) is determined by the
state of SSCEN prior to the access, ie. writing C057H to SSCCON in programming
mode (SSCEN=’0’) will initialize the SSC (SSCEN was ‘0’) and then turn it on
(SSCEN=’1’).
• When writing to SSCCON, make sure that reserved locations receive zeros.
The shift register of the SSC is connected to both the transmit pin and the receive pin via
the pin control logic (see block diagram). Transmission and reception of serial data is
synchronized and takes place at the same time, ie. the same number of transmitted bits
is also received. Transmit data is written into the Transmit Buffer SSCTB. It is moved to
the shift register as soon as this is empty. An SSC-master (SSCMS=’1’) immediately
begins transmitting, while an SSC-slave (SSCMS=’0’) will wait for an active shift clock.
When the transfer starts, the busy flag SSCBSY is set and a transmit interrupt request
(SSCTIR) will be generated to indicate that SSCTB may be reloaded again. When the
programmed number of bits (2...16) has been transferred, the contents of the shift
register are moved to the Receive Buffer SSCRB and a receive interrupt request
Bit Function (Operating Mode, SSCEN = ‘1’)
SSCBC SSC Bit Count Field
Shift counter is updated with every shifted bit. Do not write to!!!
SSCTE SSC Transmit Error Flag
1 : Transfer starts with the slave’s transmit buffer not being updated
SSCRE SSC Receive Error Flag
1 : Reception completed before the receive buffer was read
SSCPE SSC Phase Error Flag
1 : Received data changes around sampling clock edge
SSCBE SSC Baudrate Error Flag
1 : More than factor 2 or 0.5 between Slave’s actual and expected
baudrate
SSCBSY SSC Busy Flag
Set while a transfer is in progress. Do not write to!!!
SSCMS SSC Master Select Bit
0 : Slave Mode. Operate on shift clock received via SCLK.
1 : Master Mode. Generate shift clock and output it via SCLK.
SSCEN SSC Enable Bit = ‘1’
Transmission and reception enabled. Access to status flags and M/S control.
54321011 10 987615 14 13 12
- - rrw rw - -rw rw -rw
-
rw rw
SSC
BE
SSC
EN=1 SSC
MS SSC
PE SSC
RE SSC
TE -
SSC
BSY --- SSCBC
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(SSCRIR) will be generated. If no further transfer is to take place (SSCTB is empty),
SSCBSY will be cleared at the same time. Software should not modify SSCBSY, as this
flag is hardware controlled.
Note: Only one SSC (etc.) can be master at a given time.
The transfer of serial data bits can be programmed in many respects:
• the data width can be chosen from 2 bits to 16 bits
• transfer may start with the LSB or the MSB
• the shift clock may be idle low or idle high
• data bits may be shifted with the leading or trailing edge of the clock signal
• the baudrate may be set from 274.7 Baud up to 18 MBaud (@ 36 MHz CPU clock)
• the shift clock can be generated (master) or received (slave)
This allows the adaptation of the SSC to a wide range of applications, where serial data
transfer is required.
The Data Width Selection supports the transfer of frames of any length, from 2-bit
“characters” up to 16-bit “characters”. Starting with the LSB (SSCHB=’0’) allows
communication eg. with ASC devices in synchronous mode (C166 family) or 8051 like
serial interfaces. Starting with the MSB (SSCHB=’1’) allows operation compatible with
the SPI interface.
Regardless which data width is selected and whether the MSB or the LSB is transmitted
first, the transfer data is always right aligned in registers SSCTB and SSCRB, with the
LSB of the transfer data in bit 0 of these registers. The data bits are rearranged for
transfer by the internal shift register logic. The unselected bits of SSCTB are ignored, the
unselected bits of SSCRB will be not valid and should be ignored by the receiver service
routine.
The Clock Control allows the adaptation of transmit and receive behaviour of the SSC
to a variety of serial interfaces. A specific clock edge (rising or falling) is used to shift out
transmit data, while the other clock edge is used to latch in receive data. Bit SSCPH
selects the leading edge or the trailing edge for each function. Bit SSCPO selects the
level of the clock line in the idle state. So for an idle-high clock the leading edge is a
falling one, a 1-to-0 transition. The figure below is a summary.
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Figure 98 Serial Clock Phase and Polarity Options
13.1 Full-Duplex Operation
The different devices are connected through three lines. The definition of these lines is
always determined by the master: The line connected to the master's data output pin
MTSR is the transmit line, the receive line is connected to its data input line MRST, and
the clock line is connected to pin SCLK. Only the device selected for master operation
generates and outputs the serial clock on pin SCLK. All slaves receive this clock, so their
pin SCLK must be switched to input mode (DP3.13=’0’). The output of the master’s shift
register is connected to the external transmit line, which in turn is connected to the
slaves’ shift register input. The output of the slaves’ shift register is connected to the
external receive line in order to enable the master to receive the data shifted out of the
slave. The external connections are hard-wired, the function and direction of these pins
is determined by the master or slave operation of the individual device.
Note: The shift direction shown in the figure applies for MSB-first operation as well as for
LSB-first operation.
When initializing the devices in this configuration, select one device for master operation
(SSCMS=’1’), all others must be programmed for slave operation (SSCMS=’0’).
Initialization includes the operating mode of the device's SSC and also the function of
the respective port lines (see “Port Control”).
MCD01960
Last
Bit
Transmit Data
First
Bit
Latch Data
Shift Data
Pins
MTSR/MRST
Serial Clock
SCLK
SSCPO SSCPH
00
01
10
11
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Figure 99 SSC Full Duplex Configuration
The data output pins MRST of all slave devices are connected together onto the one
receive line in this configuration. During a transfer each slave shifts out data from its shift
register. There are two ways to avoid collisions on the receive line due to different slave
data:
Only one slave drives the line, ie. enables the driver of its MRST pin. All the other
slaves have to program there MRST pins to input. So only one slave can put its data onto
the master's receive line. Only receiving of data from the master is possible. The master
selects the slave device from which it expects data either by separate select lines, or by
sending a special command to this slave. The selected slave then switches its MRST line
to output, until it gets a deselection signal or command.
The slaves use open drain output on MRST. This forms a Wired-AND connection. The
receive line needs an external pullup in this case. Corruption of the data on the receive
line sent by the selected slave is avoided, when all slaves which are not selected for
transmission to the master only send ones (‘1’). Since this high level is not actively driven
onto the line, but only held through the pullup device, the selected slave can pull this line
actively to a low level when transmitting a zero bit. The master selects the slave device
MCS01963
MRST
SCLK
Device #2 Slave
Clock
Shift Register
MTSR
Clock
Master
Receive
Transmit
Device #1
Clock
MTSR
MRST
SCLK
Shift Register
MTSR
Shift Register
Clock
Slave
SCLK
MRST
Device #3
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from which it expects data either by separate select lines, or by sending a special
command to this slave.
After performing all necessary initializations of the SSC, the serial interfaces can be
enabled. For a master device, the alternate clock line will now go to its programmed
polarity. The alternate data line will go to either '0' or '1', until the first transfer will start.
After a transfer the alternate data line will always remain at the logic level of the last
transmitted data bit.
When the serial interfaces are enabled, the master device can initiate the first data
transfer by writing the transmit data into register SSCTB. This value is copied into the
shift register (which is assumed to be empty at this time), and the selected first bit of the
transmit data will be placed onto the MTSR line on the next clock from the baudrate
generator (transmission only starts, if SSCEN=’1’). Depending on the selected clock
phase, also a clock pulse will be generated on the SCLK line. With the opposite clock
edge the master at the same time latches and shifts in the data detected at its input line
MRST. This “exchanges” the transmit data with the receive data. Since the clock line is
connected to all slaves, their shift registers will be shifted synchronously with the
master's shift register, shifting out the data contained in the registers, and shifting in the
data detected at the input line. After the preprogrammed number of clock pulses (via the
data width selection) the data transmitted by the master is contained in all slaves’ shift
registers, while the master's shift register holds the data of the selected slave. In the
master and all slaves the content of the shift register is copied into the receive buffer
SSCRB and the receive interrupt flag SSCRIR is set.
A slave device will immediately output the selected first bit (MSB or LSB of the transfer
data) at pin MRST, when the content of the transmit buffer is copied into the slave's shift
register. It will not wait for the next clock from the baudrate generator, as the master
does. The reason for this is that, depending on the selected clock phase, the first clock
edge generated by the master may be already used to clock in the first data bit. So the
slave's first data bit must already be valid at this time.
Note: On the SSC always a transmission and a reception takes place at the same time,
regardless whether valid data has been transmitted or received. This is different
eg. from asynchronous reception on ASC.
The initialization of the SCLK pin on the master requires some attention in order to
avoid undesired clock transitions, which may disturb the other receivers. The state of the
internal alternate output lines is '1' as long as the SSC is disabled. This alternate output
signal is ANDed with the respective port line output latch. Enabling the SSC with an idle-
low clock (SSCPO=’0’) will drive the alternate data output and (via the AND) the port pin
SCLK immediately low. To avoid this, use the following sequence:
• select the clock idle level (SSCPO=’x’)
• load the port output latch with the desired clock idle level (P3.13=’x’)
• switch the pin to output (DP3.13=’1’)
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• enable the SSC (SSCEN=’1’)
• if SSCPO=’0’: enable alternate data output (P3.13=’1’)
The same mechanism as for selecting a slave for transmission (separate select lines or
special commands) may also be used to move the role of the master to another device
in the network. In this case the previous master and the future master (previous slave)
will have to toggle their operating mode (SSCMS) and the direction of their port pins (see
description above).
13.2 Half Duplex Operation
In a half duplex configuration only one data line is necessary for both receiving and
transmitting of data. The data exchange line is connected to both pins MTSR and MRST
of each device, the clock line is connected to the SCLK pin.
The master device controls the data transfer by generating the shift clock, while the slave
devices receive it. Due to the fact that all transmit and receive pins are connected to the
one data exchange line, serial data may be moved between arbitrary stations.
Similar to full duplex mode there are two ways to avoid collisions on the data
exchange line:
• only the transmitting device may enable its transmit pin driver
• the non-transmitting devices use open drain output and only send ones.
Since the data inputs and outputs are connected together, a transmitting device will clock
in its own data at the input pin (MRST for a master device, MTSR for a slave). By these
means any corruptions on the common data exchange line are detected, where the
received data is not equal to the transmitted data.
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Figure 100 SSC Half Duplex Configuration
Continuous Transfers
When the transmit interrupt request flag is set, it indicates that the transmit buffer SSCTB
is empty and ready to be loaded with the next transmit data. If SSCTB has been reloaded
by the time the current transmission is finished, the data is immediately transferred to the
shift register and the next transmission will start without any additional delay. On the data
line there is no gap between the two successive frames. Eg. two byte transfers would
look the same as one word transfer. This feature can be used to interface with devices
which can operate with or require more than 16 data bits per transfer. It is just a matter
of software, how long a total data frame length can be. This option can also be used eg.
to interface to byte-wide and word-wide devices on the same serial bus.
Note: Of course, this can only happen in multiples of the selected basic data width, since
it would require disabling/enabling of the SSC to reprogram the basic data width
on-the-fly.
MCS01965
Common
Transmit/
Receive
Line
MRST
SCLK
Device #2 Slave
Clock
Shift Register
MTSR
Clock
Master Device #1
Clock
MTSR
MRST
SCLK
Shift Register
Shift Register
Clock
SlaveDevice #3
SCLK
MTSR
MRST
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Port Control
The SSC uses three pins of Port 3 to communicate with the external world. Pin P3.13/
SCLK serves as the clock line, while pins P3.8/MRST (Master Receive / Slave Transmit)
and P3.9/MTSR (Master Transmit / Slave Receive) serve as the serial data input/output
lines.
The operation of these pins depends on the selected operating mode (master or slave).
In order to enable the alternate output functions of these pins instead of the general
purpose I/O operation, the respective port latches have to be set to '1', since the port
latch outputs and the alternate output lines are ANDed. When an alternate data output
line is not used (function disabled), it is held at a high level, allowing I/O operations via
the port latch. The direction of the port lines depends on the operating mode. The SSC
will automatically use the correct alternate input or output line of the ports when switching
modes. The direction of the pins, however, must be programmed by the user, as shown
in the tables. Using the open drain output feature helps to avoid bus contention problems
and reduces the need for hardwired hand-shaking or slave select lines. In this case it is
not always necessary to switch the direction of a port pin. The table below summarizes
the required values for the different modes and pins.
Note: In the table above, an 'x' means that the actual value is irrelevant in the respective
mode, however, it is recommended to set these bits to '1', so they are already in
the correct state when switching between master and slave mode.
13.3 Baud Rate Generation
The serial channel SSC has its own dedicated 16-bit baud rate generator with 16-bit
reload capability, allowing baud rate generation independent from the timers.
The baud rate generator is clocked with the CPU clock divided by 2 (fCPU/2). The timer
is counting downwards and can be started or stopped through the global enable bit
SSCEN in register SSCCON. Register SSCBR is the dual-function Baud Rate
Generator/Reload register. Reading SSCBR, while the SSC is enabled, returns the
content of the timer. Reading SSCBR, while the SSC is disabled, returns the
SSC Port Control
Pin Master Mode Slave Mode
Function Port Latch Direction Function Port Latch Direction
SCLK Serial Clock
Output
P3.13 = ’1’DP3.13=’1’Serial Clock
Input
P3.13 = ’x’DP3.13=’0’
MTSR Serial Data
Output
P3.9 = ’1’DP3.9 = ’1’Serial Data
Input
P3.9 = ’x’DP3.9 = ’0’
MRST Serial Data
Input
P3.8 = ’x’DP3.8 = ’0’Serial Data
Output
P3.8 = ’1’DP3.8 = ’1’
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programmed reload value. In this mode the desired reload value can be written to
SSCBR.
Note: Never write to SSCBR, while the SSC is enabled.
The formulas below calculate either the resulting baud rate for a given reload value, or
the required reload value for a given baudrate:
<SSCBR> represents the content of the reload register, taken as unsigned 16-bit
integer.
The maximum baud rate that can be achieved when using a CPU clock of 36 MHz is 18
MBaud in SSC Master Mode (<SSCBR>= ’0d’), while in SSC Slave Mode the maximum
baud rate is 9 MBaud (<SSCBR>= ’1d’ since <SSCBR>=’0d’ is not allowed in Slave
Mode). The minimum baud rate is 274.66 Baud (<SSCBR> = ’FFFFH’ = ’65535D’).
13.4 Error Detection Mechanisms
The SSC is able to detect four different error conditions. Receive Error and Phase Error
are detected in all modes, while Transmit Error and Baudrate Error only apply to slave
mode. When an error is detected, the respective error flag is set. When the
corresponding Error Enable Bit is set, also an error interrupt request will be generated
by setting SSCEIR (see figure below). The error interrupt handler may then check the
error flags to determine the cause of the error interrupt. The error flags are not reset
automatically (like SSCEIR), but rather must be cleared by software after servicing. This
allows servicing of some error conditions via interrupt, while the others may be polled by
software.
Note: The error interrupt handler must clear the associated (enabled) errorflag(s) to
prevent repeated interrupt requests.
A Receive Error (Master or Slave mode) is detected, when a new data frame is
completely received, but the previous data was not read out of the receive buffer register
SSCRB. This condition sets the error flag SSCRE and, when enabled via SSCREN, the
error interrupt request flag SSCEIR. The old data in the receive buffer SSCRB will be
overwritten with the new value and is unretrievably lost.
A Phase Error (Master or Slave mode) is detected, when the incoming data at pin MRST
(master mode) or MTSR (slave mode), sampled with the same frequency as the CPU
clock, changes between one sample before and two samples after the latching edge of
the clock signal (see “Clock Control”). This condition sets the error flag SSCPE and,
when enabled via SSCPEN, the error interrupt request flag SSCEIR.
BSSC = fCPU
2 * (<SSCBR> + 1) SSCBR = (
fCPU
2 * BaudrateSSC
) - 1
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A Baud Rate Error (Slave mode) is detected, when the incoming clock signal deviates
from the programmed baud rate by more than 100%, ie. it either is more than double or
less than half the expected baud rate. This condition sets the error flag SSCBE and,
when enabled via SSCBEN, the error interrupt request flag SSCEIR. Using this error
detection capability requires that the slave's baud rate generator is programmed to the
same baud rate as the master device. This feature detects false additional, or missing
pulses on the clock line (within a certain frame).
Note: If this error condition occurs and bit SSCAREN=’1’, an automatic reset of the SSC
will be performed in case of this error. This is done to reinitialize the SSC, if too
few or too many clock pulses have been detected.
A Transmit Error (Slave mode) is detected, when a transfer was initiated by the master
(shift clock gets active), but the transmit buffer SSCTB of the slave was not updated
since the last transfer. This condition sets the error flag SSCTE and, when enabled via
SSCTEN, the error interrupt request flag SSCEIR. If a transfer starts while the transmit
buffer is not updated, the slave will shift out the 'old' contents of the shift register, which
normally is the data received during the last transfer.
This may lead to the corruption of the data on the transmit/receive line in half-duplex
mode (open drain configuration), if this slave is not selected for transmission. This mode
requires that slaves not selected for transmission only shift out ones, ie. their transmit
buffers must be loaded with 'FFFFH' prior to any transfer.
Note: A slave with push/pull output drivers, which is not selected for transmission, will
normally have its output drivers switched. However, in order to avoid possible
conflicts or misinterpretations, it is recommended to always load the slave's
transmit buffer prior to any transfer.
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Figure 101 SSC Error Interrupt Control
13.5 SSC Interrupt Control
Three bit addressable interrupt control registers are provided for serial channel SSC.
Register SSCTIC controls the transmit interrupt, SSCRIC controls the receive interrupt
and SSCEIC controls the error interrupt of serial channel SSC. Each interrupt source
also has its own dedicated interrupt vector. SCTINT is the transmit interrupt vector,
SCRINT is the receive interrupt vector, and SCEINT is the error interrupt vector.
The cause of an error interrupt request (receive, phase, baudrate,transmit error) can be
identified by the error status flags in control register SSCCON.
Note: In contrary to the error interrupt request flag SSCEIR, the error status flags SSCxE
are not reset automatically upon entry into the error interrupt service routine, but
must be cleared by software.
&
SSCTEN
SSCTE
Transmit
Error
Register SSCCON
&
SSCREN
SSCRE
Receive
Error
&
SSCPEN
SSCPE
Phase
Error
&
SSCBEN
SSCBE
Baudrate
Error
1
&
SSCEIE
SSCEIR
Error
Interrupt
SSCEINT
Register SSCEIC
MCA01968
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SSCTIC (FF72H / B9H) SFR Reset Value: - - 00H
SSCRIC (FF74H / BAH) SFR Reset Value: - - 00H
SSCEIC (FF76H / BBH) SFR Reset Value: - - 00H
Note: Please refer to the general Interrupt Control Register description on page 99 for
an explanation of the control fields.
SSC
TIE
SSC
TIR
54321011 10 987615 14 13 12
rw rw- - - - rw rw----
GLVLILVL
SSC
RIE
SSC
RIR
54321011 10 987615 14 13 12
rw rw- - - - rw rw----
GLVLILVL
SSC
EIR SSC
EIE
54321011 10 987615 14 13 12
rw rw- - - - rw rw----
GLVLILVL
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SSC Clock Control Register
SSCCLC (F0B6H) Reset Value: 0000H
Bit Function
SSCDISR SSC Disable Request Bit
SSCDISR = ‘0’: SSC clock disable not requested
SSCDISR = ‘1’: SSC clock disable requested
SSCDISS SSC Disable Status Bit
SSCDISS = ‘0’: SSC clock enabled
SSCDISS = ‘1’: SSC clock disabled
SUSPEN Peripheral Suspend Enable Bit for OCDS
SUSPEN = ‘0’: Peripheral suspend disabled
SUSPEN = ‘1’: Peripheral suspend enabled
EXDISR External Disable Request
EXRDIS = ‘0’: External clock disable Request is enabled
EXRDIS = ‘1’: External clock disable Request is disabled
54321011 10 987615 14 13 12
SSC
DISR
SSC
DISS
000000
rw rrw rw
0000 00 SUS
PEN
EX
DISR
C165H
IOM-2 Interface Controller
Data Sheet 306 2001-04-19
PRELIMINARY
- EXCERPT -
14 IOM-2 Interface Controller
The C165H supports the IOM-2 interface with single/double bitrate clock in Terminal
(TE) mode, as well as the Linecard (LT) and PCM mode. The IOM-2 interface consists
of four lines: the inputs FSC and DCL as well as the bidirectional pins DD and DU.
Note: In the C165H the bitrate clock (BCL) is driven on the DCL (double bitrate clock)
line. In this document the term ’BCL’ is used to indicate the single bitrate clock.
The rising edge of FSC indicates the start of an IOM-2 frame. Typically, the FSC signal
is generated by the upstream transceiver, which synchronizes to the received framing
indication. The DCL input clock signal synchronizes the data transfer on both data lines.
For double bitrate clock the bits are shifted out with the rising edge of the first DCL clock
cycle and sampled at the falling edge of the second clock cycle. For single bitrate clock
the bits are shifted with the rising edge of the BCL and sampled with the falling edge of
the BCL.
14.1 IOM-2 and PCM Frame Structure
14.1.1 Definitions
The following definitions are used throughout the documentaion of the IOM-2 Interface
Controller.
14.1.1.1 Frame Structure
The IOM-2 frame structure is defined as:
1. A start of a frame is detected by the rising edge of the FSC signal. The length of the
FCS signal being high is irrelevant for the IOM-2 unit, as long as it comprises with the
signal specification.
2. The IOM-2 module synchronizes automatically to the frame length (i.e. number of bits/
octets) generated by the DCL signal.
3. The CLKM bit of the IOM_CR register specifies whether the DCL is a single or double
bitrate clock.
4. A frame is always 125 µs on IOM.
5. A frame always consists of multiple of 8 bit time slots.
6. The IOM-2 module does not distinguish between the different frame modes (PCM,TE,
LT). Each frame structure can be configured by specifying the corresponding time slot.
Table 64 shows a summary of design parameters for different frame structures
(e.g.Terminal Mode, the Lincard Mode and the PCM Mode).
C165H
IOM-2 Interface Controller
Data Sheet 307 2001-04-19
PRELIMINARY
- EXCERPT -
14.1.1.2 HDLC Channels on the IOM-2: B1, B2, D1, D2
The IOM-2 Interface Controller module contains two 8-bit HDLC channels and two 2-bit
HDLC channels (bit 0 and 1 of an octet). These channels can be configured to any of the
32 IOM-2 time slots. The main use for these HDLC Channels is: B1 and B2 for the 8-bit
channels and D1 and D2 for the 2-bit channels. Therefore the terms B1, B2, D1, and D2
are used throughout this document.
14.1.2 PCM Mode
The frame structure in PCM mode consists of 1..32 individual octets. This is a bit rate of
64..2048 kbit/s in steps of 64 kbit/s.
All the IOM-2 channels (e.g. B1, B2, D1, D2, CDA) can be individually mapped to any of
the 32 timeslots. Therefor any other frame mode type can be configured.
Note: There is no protection or checking for exclusive use of one timeslot by different
IOM-2 channels. This must be insured by the SW.
14.1.3 Terminal Mode
The frame structure on the IOM-2 data ports (DU,DD) in IOM-2 terminal mode is shown
in figure 102.
Table 64 IOM-2 parameters for different modes (TE, LT, PCM)
min max TE mode LT mode PCM mode
octets per FSC 1 32 12 n·4,
n∈{1,2,3,..,8}
m∈{1,2,3,..,32}
number of bits
per FSC
8 256 96 n·4·8,
n∈{1,2,3,..,8}m·8,
m∈{1,2,3,..,32}
FSC clock rate 8 kHz 8 kHz 8 kHz 8 kHz 8 kHz
BCL clock rate
(FSC · bits)
64
kHz
2048
kHz
768 kHz n·256 kHz,
n∈{1,2,3,..,8}m·64 kHz,
m∈{1,2,3,..,32}
DCL clock rate
(2·BCL)
128
kHz
4096
kHz
1536 kHz n·512 kHz,
n∈{1,2,3,..,8}m·128 kHz,
m∈{1,2,3,..,32}
C165H
IOM-2 Interface Controller
Data Sheet 308 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 102 IOM“-2 Frame Structure in Terminal Mode
The frame is composed of three channels
• Channel 0 contains 144-kbit/s of user and signaling data (2B + D1), an optional
MONITOR programming channel (MON0) and an optional command/indication
channel (CI0) for control and programming of a layer-1 transceiver, if any.
• Channel 1 contains two 64-kbit/s intercommunication channels (IC) plus a MONITOR
and command/indicate channel (MON1, CI1) to program or transfer data to other IOM-
2 devices.
• Channel 1 provides acces to an optional second signaling channel D2 in CI1(7:6)
• Channel 2 can be used for the TlC-bus access. Additionally channel 2 supports further
IC and MON channels.
Note: Each octet related to any integrated functional block can be programmed to any
of the 12 timeslots. Exceptions are the C/I0-channel, which is always related to
channel 0 (i.e. timeslot 3), C/1-channel, which is always related to channel 1 (i.e.
timeslot 7). The Monitor channel can be configured to one of 3 IOM channels in
TM mode (timeslot 2, 6 or 10) or one of 8 IOM channels in LT mode (timeslot 2, 6,
10, 14, 18, 22, 26 or 30).
C165H
IOM-2 Interface Controller
Data Sheet 309 2001-04-19
PRELIMINARY
- EXCERPT -
14.1.4 Linecard Mode
The frame structure on the IOM-2 data ports (DU,DD) in IOM-2 linecard mode is shown
in Figure 103.
Figure 103 IOM“-2 Frame Structure in Linecard Mode
The frame is composed of up to eight IOM channels (see also TM mode).
14.2 IOM-2 Handler
The IOM-2 handler offers a great flexibility for handling the data transfer between the
different functional units of the C165H and voice/data devices connected to the IOM-2
interface. Additionally it provides direct CPU access to all time slots of the IOM-2
interface via the four controller data access registers (CDA). Figure 104 shows the
architecture of the IOM-2 handler. For illustrating the functional description it contains all
configuration and control registers of the IOM-2 handler.
The Controller data access (CDA) can be configured by programming the time slot and
data port selection registers (TSDP). With the TSS bits (Time Slot Selection) the data of
the functional units can be assigned to the available time slots of the IOM-2 frame. With
the DPS bit (Data Port Selection) the output of each functional unit is assigned to either
DU or DD line respectively. The input is assigned vice versa. With the control registers
(CR) the access to the data of the functional units can be controlled by setting the
ITD09635
CH1 CH2 CH3 CH4 CH5 CH6 CH7 CH0
CH0CH7CH6CH5CH4CH3CH2CH1
B1 B2 MONITOR DC/I
MM
RX
125
FSC
DCL
DD
DU
s
µ
IOM CH0
IOM CH0
R
R
C165H
IOM-2 Interface Controller
Data Sheet 310 2001-04-19
PRELIMINARY
- EXCERPT -
corresponding control bits (EN, SWAP), see Chapter 14.5, "Controller Data Access
Handler".
The IOM-2 handler provides also access to the
• MONITOR channel (MON)
• Command Indication (C/I) channels (CI0,CI1)
• TIC bus (TIC)
• two 8-bit HDLC data channels (B1, B2)
• two 2-bit HDLC data channels (D1, D2)
The access to these channels is controlled by the registers MON_CR, CIC_CR,
IOMSEL_x. The IOM-2 interface is controlled by the control register IOM_CR.
.
Figure 104 Architecture of the IOM-2 Handler
IOM-2 Interface
Control
Data Access
(TSDP, DPS,
EN, SWAP,
MCDA, STI)
MON TIC
Data
Microcontroller Interface
IOMHAND.DRW
DU
DD
DU DD FSC DCL
IOM-2 Handler
CI0 CI1
Control
Monitor
Data
(DPS,EN
MCS)
MON_CR
IOM_CR (EN, OD)
DU
DD
x,y = 1 or 2
CDA
Register
CDA10
Controller Data
Access (CDA)
Handler
CDA_TSDPxy
CDA_CRx
MCDA
STI
MSTI
ASTI
CDA11
CDA20
CDA21
TIC Bus
Disable
Control
CI1
Data
(DPS,EN)
HDLC-0
FIFO
HDLC-1
FIFO
HDLC-2
FIFO
HDLC-3
FIFO
DPS, EN, TSS
Monitor Data
TIC Bus
Data
CI0 Data
CI1 Data D1/D2/B1/B2
Data
D1/D2/B1/B2
Data
D1/D2/B1/B2
Data
D1/D2/B1/B2
Data
CDA Data
Control
CI0
Data
(DPS, EN)
CIC_CR
C165H
IOM-2 Interface Controller
Data Sheet 311 2001-04-19
PRELIMINARY
- EXCERPT -
14.3 IOM-2 Monitor Handler
The IOM-2 MONITOR channel is utilized for information exchange between the C165H
and other devices connected to the MONITOR channel.
The MONITOR channel data can be controlled by the bits in the MONITOR control
register (MON_CR). For the MONITOR data one of the up to 3 (TE) or up to 8 (LT/PCM)
IOM channels can be selected by setting the MONITOR channel selection bits (MCS).
The DPS bit in the same register selects between an output on DU or DD respectively
and with EN_MON the MONITOR functionlity can be enabled/disabled. The default
value is MONITOR channel 0 (MON0) enabled and transmisson on DD. The following
applications may apply.
• The C165H can program and control other devices attached to the IOM-2 which do
not need a microcontroller interface.
• For data exchange between two microcontroller systems attached to two different
devices on one IOM-2 backplane. Use of the MONITOR channel avoids the necessity
of a dedicated serial communication path between the two systems. This simplifies the
system design.
14.3.1 Handshake Procedure
The MONITOR channel operates on an asynchronous basis. While data transfers on the
bus take place synchronized to frame sync, the flow of data is controlled by a handshake
procedure using the MONITOR Channel Receive (MR) and MONITOR Channel
Transmit (MX) bits. Data is placed onto the MONITOR channel and the MX bit is
activated (MX =’0’). This data will be transmitted once per 8-kHz frame until the transfer
is acknowledged via the MR bit (MR=’0’).
The MONITOR channel protocol between a Transmitter µC (µCT) and a Receiver µC
(µCR) is described In the following section and illustrated in Figure 105. The relevant
control and status bits for transmission and reception are listed in Table 65 and Table
66.
Table 65 Transmission of MONITOR Data
Control/
Status Bit
Register Bit Function
Control MOCR MXC MX Bit Control
MIE MDA and MAB Interrupt Enable
Status MOSR MDA Data Acknowledged Interrupt
MAB Data Abort Interrupt
MSTA MAC Transmission Active
C165H
IOM-2 Interface Controller
Data Sheet 312 2001-04-19
PRELIMINARY
- EXCERPT -
Table 66 Reception of MONITOR Data
Control/
Status Bit
Register Bit Function
Control MOCR MRC MR Bit Control
MIE MER Interrupt Enable
MRE MDR Interrupt Enable
Status MOSR MDR Data Received Interrupt
MER End of Reception Interrupt
C165H
IOM-2 Interface Controller
Data Sheet 313 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 105 MONITOR Channel Protocol (IOM-2)
Transmission
µC (µCT)
MIE=1
MOX=ADR
MXC=1
MAC=1
MDA Int.
MOX=DATA1
MDA Int.
MOX=DATA2
MDA Int.
MXC=0
MAC=0
MON
FF
FF
ADR
DATA1
DATA2
ADR
DATA1
DATA2
FF
FF
MX
DATA1
DATA1
DATA2
DATA2
FF
FF
1
1
0
0
1
0
0
0
1
0
0
0
1
1
1
1
MR
1
1
1
0
0
0
1
0
0
0
1
0
0
0
1
1
Reception
µC (µCR)
125µs
MDR Int.
RD MOR
(=ADR)
MRC=1
MER Int.
MRC=0
MDR Int.
RD MOR
(=DATA2)
RD MOR
(=DATA1)
MDR Int.
ADR 0 1
ADR 00
MRE=1
MIE=1
C165H
IOM-2 Interface Controller
Data Sheet 314 2001-04-19
PRELIMINARY
- EXCERPT -
Before starting a transmission, the µCT should verify that the transmitter is inactive, i.e.
that a possible previous transmission has been terminated. This is indicated by a ’0’ in
the MONITOR Channel Active MAC status bit.
After having written the MONITOR Data Transmit (MOX) register, the µCT sets the
MONITOR Transmit Control bit MXC to ’1’. This enables the MX bit to go active (0),
indicating the presence of valid MONITOR data (contents of MOX) in the corresponding
frame. As a result, the receiving device stores the MONITOR byte in its MONITOR
Receive MOR register and generates an MDR interrupt status (MRE must be ’1’).
Alerted by the MDR interrupt, the µCR reads the MONITOR Receive (MOR) register.
When it is ready to accept data (e.g. based on the value in MOR, which in a point-to-
multipoint application might be the address of the destination device), it sets the MR
control bit MRC to ’1’ to enable the receiver to store succeeding MONITOR channel
bytes and acknowledge them according to the MONITOR channel protocol. In addition,
it enables other MONITOR channel interrupts by setting MONITOR Interrupt Enable
(MIE) to ’1’.
As a result, the first MONITOR byte is acknowledged by the receiving device setting the
MR bit to ’0’. This causes a MONITOR Data Acknowledge MDA interrupt status at the
transmitter.
A new MONITOR data byte can now be written by the µCT in MOX. The MX bit is still in
the active (0) state. The transmitter indicates a new byte in the MONITOR channel by
returning the MX bit active after sending one frame in the inactive state. As a result, the
receiver stores the MONITOR byte in MOR and generates a new MDR interrupt status.
When the µCR has read the MOR register, the receiver acknowledges the data by
returning the MR bit active after sending one frame in the inactive state. This in turn
causes the transmitter to generate an MDA interrupt status.
This "MDA interrupt – write data – MDR interrupt – read data – MDA interrupt"
handshake is repeated as long as the transmitter has data to send.
When the last byte has been acknowledged by the receiver (MDA interrupt status), the
microcontroller sets the MONITOR Transmit Control bit MXC to ’0’. This enforces an
inactive (’1’) state in the MX bit. Two frames of MX inactive signifies the end of a
message. Thus, a MONITOR Channel End of Reception MER interrupt status is
generated by the receiver when the MX bit is received in the inactive state in two
consecutive frames. As a result, the microcontroller sets the MR control bit MRC to 0,
which in turn enforces an inactive state in the MR bit. This marks the end of the
transmission, making the MONITOR Channel Active MAC bit return to ’0’.
The MONITOR transfer protocol rules are summarized in the following section
• A pair of MX and MR in the inactive state for two or more consecutive frames indicates
an idle state or an end of transmission.
•A start of a transmission is initiated by the transmitter by setting the MXC bit to ’1’
enabling the internal MX control. The receiver acknowledges the received first byte by
setting the MR control bit to ’1’ enabling the internal MR control.
C165H
IOM-2 Interface Controller
Data Sheet 315 2001-04-19
PRELIMINARY
- EXCERPT -
• The internal MX,MR control indicates or acknowledges a new byte in the MON slot by
toggling MX,MR from the active to the inactive state for one frame.
• Two frames with the MX-bit in the inactive state indicate the end of transmission.
• Two frames with the MR-bit set to inactive indicate a receiver request for abort (see
Chapter 14.3.2).
• The transmitter can delay a transmission sequence by sending the same byte
continuously. In that case the MX-bit remains active in the IOM-2 frame following the
first byte occurrence.
•Since a double last-look criterion is implemented the receiver is able to receive the
MON slot data at least twice (in two consecutive frames). The receiver acknowledge
the data after the reception of two identical bytes in two successive frames.
• To control this handshake procedure a collision detection mechanism is implemented
in the transmitter. This is done by making a collision check per bit on the transmitted
MONITOR data and the MX bit.
• Monitor data will be transmitted repeatedly until its reception is acknowledged or the
transmission time-out timer expires.
• Two frames with the MX bit in the inactive state indicates the end of a message
(EOM).
• MONITOR control commands are processed sequential that means e.g. during a read
on a register no further command is executed.
14.3.2 Abort Procedure
During a transmission process, it is possible for the receiver to ask a transmission to be
aborted by sending an inactive MR bit value in two consecutive frames. This is effected
by the microcontroller writing the MR control bit MRC to ’0’. An aborted transmission is
indicated by a MONITOR Channel Data Abort MAB interrupt status at the transmitter.
The MX/MR bits are under control of the microcontroller through MXC or MRC
respectively. An abort is indicated by an MAB interrupt or MER interrupt respectively.
A transmission is aborted by the C165H if
• abort request from receiver is detected (see Figure 106)
• a collision on the IOM bus of the MONITOR data or MX bit occurs
• a recommended software timer (GPT) expires
A reception is aborted by the C165H if
• an abort request from the transmitting device occurs, see Figure 107. This abort
request has basically the same waveform as an end of transmission, see Figure 108.
Note: In case the C165H does not detect identical monitor messages in two successive
frames, transmission is not aborted. Instead the C165H will wait until two identical
bytes are received in succession.
C165H
IOM-2 Interface Controller
Data Sheet 316 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 106 Monitor Channel, Transmission Abort requested by the Receiver
Figure 107 Monitor Channel, Transmission Abort requested by the Transmitter
MX (DU)
IOM -2 Frame No. 1 2 34567
EOM
MR (DD)
1
0
1
0
mon_rec-abort.vsd
Abort Request from Receiver
MR (DU)
IOM -2 Frame No. 1 2 34567
MX (DD)
1
0
1
0
EOM
mon_tx-abort.vsd
Abort Request from Transmitter
C165H
IOM-2 Interface Controller
Data Sheet 317 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 108 Monitor Channel, normal End of Transmission
Note: The Monitor Time-Out register bit, known from other Infineon devices, is not
implemented within the C165H. To prevent lock-up situations in a MONITOR
transmission, a GPT Timer can be programmed accordingly.
14.3.3 MONITOR Interrupt Logic
Figure 109 shows the MONITOR interrupt structure of the C165H. The MONITOR Data
Receive interrupt status MDR has two enable bits, MONITOR Receive interrupt Enable
(MRE) and MR bit Control (MRC). The MONITOR channel End of Reception MER,
MONITOR channel Data Acknowledged MDA and MONITOR channel Data Abort MAB
interrupt status bits have a common enable bit MONITOR Interrupt Enable MIE.
MRE inactive (0) prevents the occurrence of MDR status, including when the first byte of
a packet is received. When MRE is active (1) but MRC is inactive, the MDR interrupt
status is generated only for the first byte of a receive packet. When both MRE and MRC
are active, MDR is always generated and all received MONITOR bytes - marked by a 1-
to-0 transition in MX bit - are stored. (Additionally, an active MRC enables the control of
the MR handshake bit according to the MONITOR channel protocol.)
MR (DU)
IOM -2 Frame No. 1 2 34567
MX (DD)
1
0
1
0
EOM
mon_norm.vsd
8
C165H
IOM-2 Interface Controller
Data Sheet 318 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 109 MONITOR Interrupt Structure
14.4 C/I Channel Handler
The Command/Indication channel carries real-time status information between the
C165H and another device connected to the IOM.
14.4.1 C/I0 - Command/Indication 0
One C/I channel (called C/I0) conveys the commands and indications between the
C165H and an external layer-1 device. C/I0 channel access may be arbitrated via the
TIC bus access protocol. In this case the arbitration is done in C/I channel 2 (timeslot 1),
see Figure 102.
The C/I0 channel is accessed via register bit CIC0_D.CODR0 (in receive direction, layer-
1 to layer-2) and register CIC0_D.CODX0 (in transmit direction, layer-2 to layer-1). The
C/I0 code is four bits long. In the receive direction, the code from layer-1 is continuously
monitored, with an interrupt being generated anytime a change occurs (ISTA.CIC). A
new code must be found in two consecutive IOM frames to be considered valid and to
trigger a C/I code change interrupt status (double last look criterion).
In the transmit direction, the code written in CIX0 is continuously transmitted in C/I0.
14.4.2 C/I1 - Command/Indication 1
A second C/I channel (called C/I1) can be used to convey real time status information
between the C165H and various non-layer-1 peripheral devices. The C/I1 channel
consists of four or six bits in each direction.The width can be changed from 4bit to 6bit
by setting bit CIC_CMD.CICW.
The C/I1 channel is accessed via registers CIC1_D.CODR1 and CIC1_D.CODX1. A
change in the received C/I1 code is indicated by an interrupt status without double last
look criterion.
CIC
ST
MOS
HDLC
IOMINT
ISTA
MASK
CIC
ST
MOS
MRE MDR
MIE MDA
MER
MAB
MOSR
MOCR
4x
HDLC
4x
C165H
IOM-2 Interface Controller
Data Sheet 319 2001-04-19
PRELIMINARY
- EXCERPT -
Note: The function of the C/I1 channel change detection (CIC_ST.CI1) gets disabled
when disabling the according interrupt (CIC_CMD.CI1E set to ’0’).
14.4.3 CIC Interrupt Logic
Figure 110 shows the CIC interrupt structure.
A CIC interrupt may originate
• from a change in received C/I channel 0 code (CIC0_D.CODR_0) or
• from a change in received C/I channel 1 code (CIC1_D.CODR_1).
The two corresponding status bits CIC0 and CIC1 are in CIC_ST register. CIC1 can be
individually disabled by clearing the enable bit CI1E in the CIX1 register. In this case the
occurrence of a code change in CIR1 will not be displayed by CIC1 until the
corresponding enable bit has been set to one.
Bits CIC0 and CIC1 are cleared by writing ’1’ into the specific bit.
An interrupt status is issued every time a valid new code is loaded into CIR0 or CIR1.
The CIR0 is buffered with a FIFO size of two. If a second code change occurs in the
received C/I channel 0 before the first one has been read, immediately after reading of
CIR0 a new interrupt will be generated and the new code will be stored in CIR0. If several
consecutive codes are detected, only the first and the last code is obtained at the first
and second register read, respectively.
For CIR1 no buffering is available. The actual code of the received C/I channel 1 is
always stored in CIR1.
Figure 110 CIC Interrupt Structure
14.4.4 D-Channel Access Control
D-channel access control is defined to guarantee all connected HDLC controllers a fair
chance to transmit data in the D-channel. Collisions are possible on the IOM-2 interface,
CIC
ST
MOS
HDLC
IOMINT
ISTA
MASK
CIC1
CI1E
CIC0
CIR0
CIX1
CIC
ST
MOS
4x
HDLC
4x
C165H
IOM-2 Interface Controller
Data Sheet 320 2001-04-19
PRELIMINARY
- EXCERPT -
if there is more than one HDLC controller connected. This arbitration mechanism is
implemented in the C165H and will be described in the following chapter.
Note: D-channel access control is only necessary if several D-channel controllers try to
access the same space on the IOM-2 bus.
Note: The TIC Bus D-Channel Access Control mechanism, as described in
Chapter 14.4.4.1, is implemented for HDLC-2 controller only.
14.4.4.1 TIC Bus D-Channel Access Control for HDLC-2 Controller
The TIC bus is implemented to organize the access to the layer-1 functions of the
transceiver device via IOM-2 interface (C/I-channel) and to the D-channel from up to 7
external communication controllers.
The arbitration mechanism is implemented in the last octet in IOM channel 2 of the IOM-2
interface (IOM-2 TE Mode only, TIC_DIS in IOM_CR is disabled). An access request to
the TIC bus may either be generated by software (MP access to the C/I channel) or by
the C165H itself (transmission of an HDLC frame in the D-channel). A software access
request to the bus is effected by setting the BAC bit (CIC_CMD register) to ’1’.
In the case of an access request, the C165H checks the Bus Accessed-bit BAC (bit 5 of
DU last octet of channel 2) for the status "bus free“, which is indicated by a logical ’1’. If
the bus is free, the C165H transmits its individual TIC bus address TAD programmed in
the CIC_CMD register and compares it bit by bit with the value on DU. If a sent bit set to
’1’ is read back as ’0’ because of the access of another D-channel source with a lower
TAD, the C165H withdraws immediately from the TIC bus. The TIC bus is occupied by
the device which sends its address error-free. If more than one device attempt to seize
the bus simultaneously, the one with the lowest address wins and starts D-channel
transmission.
Figure 111 Structure of Last Octet of Ch2 on DU
DU
tic_octet-du.vsd
B1 B2 MON0 IC1 IC2 MON1 CI1CI0D
BAC
TAD
MX
MR
MX
MR
BAC TAD
201
TIC-Bus Address (TAD 2-0)
Bus Accessed ('1' no TIC-Bus Access)
C165H
IOM-2 Interface Controller
Data Sheet 321 2001-04-19
PRELIMINARY
- EXCERPT -
When the TIC bus is seized by the C165H, the bus is identified to other devices as
occupied via the DU channel 2 Bus Accessed-bit state ’0’ until the access request is
withdrawn. After a successful bus access, the C165H is automatically set into a lower
priority class, that is, a new bus access cannot be performed until the status "bus free"
is indicated in two successive frames.
If none of the devices connected to the IOM interface requests access to the D channel,
the TIC bus address 7 will be present. The device with this address will therefore have
access, by default, to the D channels.
Note: Bit BAC (CIC_CMD register) should be reset by the µP when access to the C/I
channels is no more requested, to grant other devices access to the D and C/I
channels.
The availability of the line interface D channel is indicated in bit 5 "S/G" (S/G) of the DD
last octet of channel 2.
S/G = 1: stop
S/G = 0: go
After the BAC bit has been set to active and the C165H has achieved the lowest TAD,
the S/G bit is checked in order to avoid collision with external layer 1 devices sending on
the D-channel.
Figure 112 Structure of Last Octet of Ch2 on DD
14.5 Controller Data Access Handler
The C165H IOM-2 handler provides with his four controller data access registers
(CDA10, CDA11, CDA20, CDA21) a very flexible solution for the access to any possible
timeslot.
The functional unit CDA (controller data access) allows with its control and configuration
registers
DD
tic_octet-du.vsd
B1 B2 MON0 IC1 IC2 MON1 CI1CI0D
MX
MR
MX
MR
S/G
Stop/Go
EE
S/G
C165H
IOM-2 Interface Controller
Data Sheet 322 2001-04-19
PRELIMINARY
- EXCERPT -
• looping of up to four independent IOM-2 interface channels from DU to DD or vice
versa over the four CDA registers
• shifting or switching of two independent IOM-2 interface channels to another two
independent IOM-2 interface channels on both data ports (DU, DD)
• monitoring of up to four time slots on the IOM-2 interface simultaneously
• microcontroller read and write access to each IOM-2 interface channel
14.5.1 Description
The access principle which is identical for the two channel register pairs CDA10/11 and
CDA20/21 is illustrated in Figure 113. The index variables x,y used in the following
description can be 1 or 2 for x, and 0 or 1 for y. The prefix ’CDA_’ from the register names
has been omitted for simplification.
To each of the four CDAxy data registers a TSDPxy register is assigned which specifies
the time slot and the data port. With the TSS (Time Slot Selection) bits a time slot from
0...31 can be selected. With the DPS (Data Port Selection) bit the output of the CDAxy
register can be assigned to DU or DD respectively. The time slot and data port for the
output of CDAxy is always defined by its own TSDPxy register. The input of CDAxy
depends on the SWAP bit in the control registers CDAx_CR.
If the SWAP bit = ’0’ the time slot and data port for the input and output of the CDAxy
register is defined by its own TSDPxy register. The data port for the CDAxy input is vice
versa to the output setting for CDAxy.
If the SWAP bit = ’1’, the input port and time slot of the CDAx0 is defined by the TSDP
register of CDAx1 and the input port and time slot of CDAx1 is defined by the TSDP
register of CDAx0.
The input and output of every CDAxy register can be enabled or disabled by setting the
corresponding EN (-able) bit in the control register CDAx_CR. If the input of a register is
disabled the output value in the register is retained.
C165H
IOM-2 Interface Controller
Data Sheet 323 2001-04-19
PRELIMINARY
- EXCERPT -
.
Figure 113 Data Access via CDAx0 and CDAx1 register pairs
14.5.2 Looping and Shifting Data
Figure 114 gives examples for typical configurations with the above explained control
and configuration possibilities with the bits TSS, DPS, EN and SWAP in the registers
TSDPxy or CDAx_CR:
a) looping IOM-2 time slot data from DU to DD or vice versa (SWAP = ’0’)
b) shifting data from TSa to TSb on DU and DD (SWAP = ’1’)
c) switching data from TSa (DU) to TSb(DD) and TSb (DU) to TSa (DD)
DU
CDAx1
Control
Register
CDA_CRx
DD
11
Time Slot
Selection (TSS)
Input
Swap
(SWAP)
1
x = 1 or 2; a,b = 0...11
Data Port
CDA_TSDPx1
01
0
1
IOM_HAND.FM4
10
11
Enable
input
(EN_O0)
output
CDA_TSDPx0
1
0
CDAx0
1
(EN_I0) (EN_I1)
inputEnable
output
(EN_O1)
Selection (DPS)
Data Port
Selection (DPS) Selection (TSS)
Time Slot
TSa
TSa
TSb
TSb
C165H
IOM-2 Interface Controller
Data Sheet 324 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 114 Examples for Data Access via CDAxy Registers
a) Looping Data
b) Shifting Data
c) Switching Data
TSa TSb
CDAx0
TSa TSb
DU
DD
TSa TSb DU
DD
b) Shifting Data
a) Looping Data
.TSS:
.DPS
.SWAP ’0’’1’
’0’
TSa TSb
.TSS:
.DPS
.SWAP ’1’’1’
’0’
TSa TSb DU
DD
c) Switching Data
TSa TSb
.TSS:
.DPS
.SWAP ’1’’0’
’0’
.x = 1 or 2
CDAx0
CDAx0 CDAx0
CDAx0 CDAx0
C165H
IOM-2 Interface Controller
Data Sheet 325 2001-04-19
PRELIMINARY
- EXCERPT -
14.5.3 Monitoring Data
Figure 115 gives an example for monitoring of two IOM-2 time slots each on DU or DD
simultaneously.
.
Figure 115 Example for Monitoring Data
Note: Due to the hardware design, there are some restrictions for the CDA Monitoring
Data Function. These restrictions apply if the CDA Monitoring Function is used to
monitor other active functions (e.g. B1, B2, D1, D2, TIC, CIC, Monitor).
These restrictions do not apply if the DPS setting of the monitoring CDA channel
and the active channel are different.
If the DPS setting of the monitoring CDA channel is equal to the DPS setting of the
monitored active channel, following rules apply:
• In case of monitoring B1, Monitor, TIC the data is stored in the specified CDA_xy
register (normal function).
• In case of monitoring B2, D1, D2, CIC the data is stored in the reverse CDA_xy
register. For example, when activating CDA_10, it is stored in CDA_11 and if CDA_11
activated, it is stored in CDA_10.
CDA10 CDA11
CDA20 CDA21
TS(2n) TS(2m+1) DU
DD
a) Monitoring Data
TSS:
TS(2n) TS(2m+1)
TSS: ’1’’1’
DPS:
’0’’0’
DPS:
’0’’0’
EN_O:
’1’’1’
EN_I:
’0’’0’
EN_O: ’1’’1’EN_I:
CDA_CR1.
CDA_CR2.
n,m = 0...5
C165H
IOM-2 Interface Controller
Data Sheet 326 2001-04-19
PRELIMINARY
- EXCERPT -
14.5.4 Synchronous Transfer
While looping, shifting and switching the data can be accessed by the controller between
the synchronous transfer interrupt (STI) and the status overflow interrupt (STOV).
The microcontroller access to the CDAxy registers can be synchronized by means of
four programmable synchronous transfer interrupts (STIxy) and synchronous transfer
overflow interrupts (STOVxy) in the STI register.
Depending on the DPS bit in the corresponding CDA_TSDPxy register the STIxy is
generated two (for DPS=’0’) or one (for DPS=’1’) BCL clock after the selected time slot
(CDA_TSDPxy.TSS). One BCL clock is equivalent to two DCL clocks.
A non masked synchronous transfer overflow (STOVx0y0) interrupt is generated if the
appropriate STIx1y1 is not acknowledged in time. The STIx1y1 is acknowledged in time if
bit ACKx1y1 in the ASTI register is set to ’1’ one BCL clock (for DPS=’0’) or zero BCL
clocks (for DPS=’1’) before the time slot which is selected for the appropriate STOVx0y0.
If STIx1y1 and STOVx1y1 are not masked STOVx1y1 is only related to STIx1y1 (see
example a), c) and d) of Figure 117).
If STIx1y1 is masked but STOVx1y1 is not masked, STOVx0y0 is related to each enabled
STIxy (see example b) and d) of Figure 117).
Setting the corresponding bits in the MSTI (Mask Synchronous Transfer Interrupts)
register masks the STIxy and the STOVxy interrupt. The interrupt structure of the
synchronous transfer is shown in Figure 116. Examples of the described synchronous
transfer interrupt controlling are illustrated in Figure 117. A read to the STI register
clears the STIxy and STOVxy interrupts.
.
Figure 116 Interrupt Structure of the Synchronous Data Transfer
CIC
ST
MOS
HDLC HDLC
CIC
ST
MOS
IOMINT
STI11
ISTA
MASK
MSTI STI
STI10
STI20
STI21
STOV10
STOV11
STOV20
STOV21
STI11
STI10
STI20
STI21
STOV10
STOV11
STOV20
STOV21
ACK11
ASTI
ACK10
ACK20
ACK21
4x
4x
C165H
IOM-2 Interface Controller
Data Sheet 327 2001-04-19
PRELIMINARY
- EXCERPT -
.
Figure 117 Examples for the Synchronous Transfer Interrupt Control with one
enabled STIxy
Figure 118 shows the timing of looping TSa on DU to TSa on DD (a = 0...11) via CDAxy
register. TSa is read in the CDAxy register from DU and is written one frame later on DD.
xy: 10 11 21 20
CDA_TDSPxy.TSS: TS0 TS1 TS5 TS11
MSTI.STIxy: '0' '1' '1' '1'
MSTI.STOVxy: '0' '1' '1' '1'
TS7TS5 TS6TS4TS3TS1 TS2TS0 TS11TS9 TS10TS8 TS0TS11
a) Interrupts for data access to time slot 0 (B1 after reset), MSTI.STI10 and MSTI.STOV10 enabled
xy: 10 11 21 20
CDA_TDSPxy.TSS: TS0 TS1 TS5 TS11
MSTI.STIxy: '0' '1' '1' '1'
MSTI.STOVxy: '1' '1' '1' '0'
TS7TS5 TS6TS4TS3TS1 TS2TS0 TS11TS9 TS10TS8 TS0TS11
b) Interrupts for data access to time slot 0 (B1 after reset), STOV interrupt used as flag for "last possible CDA
access"; MSTI.STI10 and MSTI.STOV20 enabled
c) Interrupts for data access to time slot 0 and 1 (B1 and B2 after reset), MSTI.STI10, MSTI.STOV10,
MSTI.STI11 and MSTI.STOV11 enabled
sti_stov.vsd
xy: 10 11 21 20
CDA_TDSPxy.TSS: TS0 TS1 TS5 TS11
MSTI.STIxy: '0' '0' '1' '1'
MSTI.STOVxy: '0' '0' '1' '1'
TS7TS5 TS6TS4TS3TS1 TS2TS0 TS11TS9 TS10TS8 TS0TS11
d) Interrupts for data access to time slot 0 (B1 after reset), STOV20 interrupt used as flag for "last possible CDA
access", STOV10 interrupt used as flag for "CDA access failed"; MSTI.STI10, MSTI.STOV10 and
MSTI.STOV20 enabled
xy: 10 11 21 20
CDA_TDSPxy.TSS: TS0 TS1 TS5 TS11
MSTI.STIxy: '0' '1' '1' '1'
MSTI.STOVxy: '0' '1' '1' '0'
TS7TS5 TS6TS4TS3TS1 TS2TS0 TS11TS9 TS10TS8 TS0TS11
: STOV interrupt generated for a not acknowledged STI interrupt
: STI interrupt generated
C165H
IOM-2 Interface Controller
Data Sheet 328 2001-04-19
PRELIMINARY
- EXCERPT -
.
Figure 118 Data Access when Looping TSa from DU to DD
Figure 119 shows the timing of shifting data from TSa to TSb on DU(DD). In
Figure 119a) shifting is done in one frame because TSa and TSb didn’t succeed direct
one another (a,b = 0...9 and b = a+2). In Figure 119b) shifting is done from one frame
to the following frame. This is the case when the time slots succeed one other (b = a+1)
or b is smaller than a (b < a).
TSa
DU TSa
FSC
CDAxy
µC
RD
WR
ACK
STOV
TSa
DD TSa
STI
a = 0...11
*) if access by the µC is required
*)
STI
C165H
IOM-2 Interface Controller
Data Sheet 329 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 119 Data Access when Shifting TSa to TSb on DU (DD)
14.6 Bus Activation / Deactivation (Power Down)
The IOM-2 bus has an activation/deactivation capability. Activation and deactivation can
be initiated from either the upstream or downstream component on the bus. When
deactivated, DCL is held low and the data lines are held high. The activation/deactivation
procedure is a combination of software handshakes via the C/I channel, and hardware
indications via the clock and data lines.
TSa
DU TSb
FSC
CDAxy
µC
RD
WR
ACK
STOV
STI
TSa
STI
TSa
CDAxy
µC
RD
WR
ACK
STOV
STI
TSb TSa TSb
(DD)
(a,b: 0...11 and (b = a+1 or b <a)
DU
(DD)
(a,b: 0...11 and b ≥ a+2)
a) Shifting TSa → TSb within one frame
b) Shifting TSa → TSb in the next frame
*) if access by the µC is required
*)
*)
STI
FSC
C165H
IOM-2 Interface Controller
Data Sheet 330 2001-04-19
PRELIMINARY
- EXCERPT -
In this chapter the hardware related parts are described.
14.6.1 Deactivation Request, Downstream (C165H) to Upstream
There is currently no defined procedure for requesting deactivation from downstream.
The deactivation procedure is shown in Figure 120. After detecting the code DI
(Deactive Indication) from the downstream unit, the upstream unit responds by
transmitting DC (Deactive confirmation) during subsequent frames. The upstream unit
stops sending timing signals after it has transmitted the last bit of the fourth consecutive
DC command.
Figure 120 Deactivation of the IOM-2 Interface
The IOM-2 Handler contains a DCL clock supervision unit. This unit is a counter which
is set to the DCL Clock Supervision Interval (DCSI) at each rising edge of the DCL clock
and counts down with each XBus clock. Once the counter reaches ’0’, it remains at this
value. If the counter is ’0’, the bit CIC_ST.DCOD is set to ’1’, otherwise CIC_ST.DCOD
is set to ’0’.
Any change in CIC_ST.DCOD results in setting the ISTA.DCSI interrupt.
ITD09655
DIU
DIDDR
FSC
DU
DD
Deactivated
D
B2 MONO DB1
CIO
CIO
DCL
R
IOM -2 IOM -2
R
DIU DIU DIU DIU DIU DIU DIU DIU
DR DR DR DR DID DID DID
C165H
IOM-2 Interface Controller
Data Sheet 331 2001-04-19
PRELIMINARY
- EXCERPT -
Note: The DCSI must be set in relation to the DCL frequency and the actual XBus
frequency. If the DCL clock is active, the DCL clock supervision counter should not
be able to count downto zero before the next rising edge of the DCL clock.
At the detection of the ISTA.DCSI interrupt and CIC_ST.DCOD being ’1’ (this indicates
the DCL clock has been switched off by the upstream device) the CPU of the C165H can
deactivate the IOM-2 module.
14.6.2 Deactivation, Upstream to Downstream (C165H)
The upstream unit can initiate deactivation via a series of software handshakes via the
C/I channel. The upstream unit issues a deactivation request and waits for a deactivation
indication from all downstream units. Once this is received, a deactivation confirmation
is issued, followed by the stopping of DCL and FSC, and the placing of the output pin in
a high impedance state. After the clocks are stopped, the input pin is monitored for the
presence of a timing request from the downstream unit (the input pin being pulled LOW).
The deactivation procedure is shown in Figure 120. After detecting the code DIU
(Deactivate Indication Upstream) the layer 1 of the C165H responds by transmitting DID
(Deactivate Indication Downstream) during subsequent frames and stops the timing
signals synchronously with the end of the last C/I (C/I0) channel bit of the fourth frame.
The detection of the DCL shut off is the same as in Chapter 14.6.1.
14.6.3 Activation Request, Downstream (C165H) to Upstream
The downstream unit can request that the clocks be restarted by pulling its data output
line (DU) LOW (this is called a timing request). In order to pull the output line to LOW,
the bit IOM_CR.SPU must be set to ’1’. Once the clocks are restarted, the downstream
units requests activation by sending an activation request upstream over the C/I channel.
After the clocks have been enabled, this may be indicated by the PU code in the C/I
channel.The downstream unit may then insert a valid code in the C/I channel.The
continuous supply of timing signals by the upstream unit is ensured as long as there is
no DI indication in the upstream C/I channel. If timing signals are no longer required and
activation is not yet requested, the downstream unit may indicate this by sending DI.
14.6.4 Activation, Upstream to Downstream (C165H)
The upstream unit activates the bus by starting the clocks and following the C/I channel-
based activation handshake procedure (see Figure 121).
The DCL is directly connected to the fast interrupt which is held ’0’ while the DCL clock
is inactive. Once the DCL is activated, the interrupt is triggered and the CPU can activate
the IOM-2 Handler unit.
C165H
IOM-2 Interface Controller
Data Sheet 332 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 121 Activation of the IOM-2 Interface
14.7 HDLC Controller
The four HDLC controllers handle layer-2 functions of the D- channel protocol (LAPD) or
B-channel protocols. They can access each of the four IOM-2 channels (B1, B2, D1, D2)
at a time or any combination of them e.g. 18 bit IDSL data (2B+D) by setting the enable
HDLC channel bits (EN_D1, EN_B1H, EN_B2H) in the IOM_SEL register.
Note: The TIC Bus D-Channel Access Control feature is implemented for HDLC-2
controller only, please refer to Chapter 14.4.4.1, page 320.
The HDLC controller perform the framing functions used in HDLC based communication:
flag generation/recognition, bit stuffing, CRC check and address recognition.
ITD09656
~
~~
~~
~
~
~
~
~
~
~
~
~
~
~
~
~
~
~
~
~
~
~
~
~~
~
~
~
FSC
DU
DD
FSC
DU
DD
DCL
SPU = 1 SPU = 0
CIC : CIXO = TIM
Int.
TIM
PU
B1
B1MXMR
0.2 to 4 ms
132 x DCL
TIM TIM
PU PU PU PU
R
IOM -CH1 R
IOM -CH2
IOM -CH2
R
IOM R-CH1
C165H
IOM-2 Interface Controller
Data Sheet 333 2001-04-19
PRELIMINARY
- EXCERPT -
One 8 byte FIFO for the receive and one for the transmit direction is available for each
HDLC controller.
Note: In the following the description is focused on one HDLC controller only. The same
information applies to all other HDLC controller as well, since they are identical
with the exception of TIC Bus D-Channel Access Control (as noted above).
14.7.1 Message Transfer Modes
A HDLC controller can be programmed to operate in various modes, which are different
in the treatment of the HDLC frame in receive direction. Thus the receive data flow and
the address recognition features can be programmed in a flexible way to satisfy different
system requirements.
The structure of a LAPD two-byte address is shown below.
For the address recognition the HDLC controller contains four programmable registers
for individual SAPI and TEI values (SAP1, 2 and TEI1, 2), plus two fixed values for the
“group” SAPI (SAPG = ’FE’ or ’FC’) and TEI (TEIG = ’FF’).
The received C/R bit is excluded from the address comparison. EA is the address field
extension bit which is set to ’1’ for LAPD protocol.
There are 5 different operating modes which can be selected via the mode selection bits
MDS2-0 in the MODEH register:
14.7.1.1 Non-Auto Mode (MDS2-0 = ’01x’)
Characteristics: Full address recognition with one-byte (MDS = ’010’) or
two-byte (MDS = ’011’) address comparison
All frames with valid addresses are accepted and the bytes following the address are
transferred to the µP via RFIFO.
14.7.1.2 Transparent Mode 0 (MDS2-0 = ’110’).
Characteristics: no address recognition
Every received frame is stored in RFIFO (first byte after opening flag to CRC field).
14.7.1.3 Transparent Mode 1 (MDS2-0 = ’111’).
Characteristics: SAPI recognition
A comparison is performed on the first byte after the opening flag with SAP1, SAP2 and
“group” SAPI (FEH/FCH). In the case of a match, all following bytes are stored in RFIFO.
High Address Byte Low Address Byte
SAPI1, 2, SAPG C/R 0 TEI 1, 2, TEIG EA
C165H
IOM-2 Interface Controller
Data Sheet 334 2001-04-19
PRELIMINARY
- EXCERPT -
14.7.1.4 Transparent Mode 2 (MDS2-0 = ’101’).
Characteristics: TEI recognition
A comparison is performed only on the second byte after the opening flag, with TEI1,
TEI2 and group TEI (FFH). In case of a match the rest of the frame is stored in the RFIFO.
14.7.1.5 Extended Transparent Mode (MDS2-0 = ’100’).
Characteristics: fully transparent
In extended transparent mode fully transparent data transmission/reception without
HDLC framing is performed i.e. without FLAG generation/recognition, CRC generation/
check, bitstuffing mechanism. This allows user specific protocol variations.
Note: The extended Transparent Mode of the C165H is implemented according to the
so called "LSB-First" methode. If the "MSB-First" methode is needed, e.g. for voice
traffic application, a look-up table using software could be applied.
14.7.2 Data Reception
14.7.2.1 General Description
The 8-byte RFIFO is controlled by the CPU, which will act as master. The control of the
data transfer between the CPU and the HDLC controller is handled via interrupts (HDLC
controller → CPU) and commands (CPU → HDLC controller).
There are four different interrupt indications in the ISTAH register concerned with the
reception of data:
–RPF (Receive Pool Full) interrupt, indicating that a data word/byte can be read from
RFIFO.
–RME (Receive Message End) interrupt, indicating that the reception of one message
is completed.
–RFO (Receive Frame Overflow) interrupt, indicating that a complete frame could not
be stored in RFIFO and is therefore lost as the RFIFO is occupied. This occurs if the
CPU fails to respond quickly enough to RPF/RME interrupts since previous data was
not read by the CPU.
–FFO (Following Frame Overflow) interrupt, indicating that a new frame could not be
stored in the RFIFO and therefore lost as the RFIFO is occupied. This occurs if either
there is still data in the RFIFO of the previous frame or the CPU has not acknowledged
the RME interrupt. Acknowledgment is done by writing ’1’ to the RME bit.
There is one control command that is used with the reception of data:
–RRES (Receiver Reset) command, resetting the HDLC receiver and clearing the
receive FIFO of any data (e.g. used before start of reception). It has to be used after
having changed the mode.
C165H
IOM-2 Interface Controller
Data Sheet 335 2001-04-19
PRELIMINARY
- EXCERPT -
14.7.2.2 Possible Error Conditions during Reception of Frames
If parts of a frame get lost because the receive FIFO is full, the Receive Data Overflow
(RDO) byte in the STAR register will be set. In addition, the RFO interrupt will be set. If
a complete frame is lost the receiver will assert a Receive Frame Overflow (RFO)
interrupt or an Following Frame Overflow (FFO) interrupt, depending on the situation.
If the microcontroller reads data without a prior RME or RPF interrupt, the read data is
undefined.
14.7.2.3 Receive Frame Structure
The management of the received HDLC frames as affected by the different operating
modes is shown in Figure 122.
C165H
IOM-2 Interface Controller
Data Sheet 336 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 122 Receive Data Flow
The HDLC controller indicates to the host that a new data block can be read from the
RFIFO by means of an RPF interrupt (see previous chapter). User data is stored in the
RFIFO and information about the received frame is available in the STAR and RBC
registers which are listed in Table 67.
FLAG
fifoflow_rec.vsd
MDS0MDS2 MDS1 MODE
CTRL CRC FLAGI
ADDRESS CONTROL DATA STATUS
ADDR
001 Non
Auto/8
TEI1
TEI2
RFIFO
STAR
*
1)
*
2)
*
3)
011 Transparent 0 RFIFO
STAR
*
1)
101 Non
Auto/16
SAP1
SAPG
SAP2
TEI1
TEIG
TEI2
RFIFO
STAR
*
1)
*
2)
*
2)
111 Transparent 1
SAP1
SAPG
SAP2
RFIFO
STAR
*
1)
*
2)
110 Transparent 2
RFIFO
STAR
*
1)
TEI1
TEIG
TEI2
*
2)
Description of Symbols:
Compared with Registers
Stored in FIFO/Registers
*
1)
CRC optionally stored in RFIFO if MODEH.RCRC = 1
*
2)
Address optionally stored in RFIFO if MODEH.SRA = 1
*
3)
Start of the Control Field in Case of a 8 Bit Address
C165H
IOM-2 Interface Controller
Data Sheet 337 2001-04-19
PRELIMINARY
- EXCERPT -
14.7.3 Data Transmission
14.7.3.1 General Description
The 8-byte register FIFO buffer is controlled by the CPU for transmission.
There are three different interrupt indications in the ISTAH register concerned with the
transmission of data:
–XPR (Transmit Pool Ready) interrupt, indicating that a data word/byte can be written
to the TFIFO.
An XPR interrupt is generated either
- after an XRES (Transmitter Reset) command (which is issued for example for
frame abort) or
- when data from the TFIFO is transmitted and the corresponding FIFO can
accept further data from the host.
–XDU (Transmit Data Underrun) interrupt, indicating that the transmission of the
current frame has been aborted (seven consecutive ’1’s are transmitted) as the TFIFO
Table 67 Receive Information at RME Interrupt
Information Location Bit Mode
Type of frame
(Command/
Response)
RFIFO
(last byte)
C/R Non-auto mode,
2-byte address field
Transparent mode 1
Recognition of SAPI RFIFO
(last byte)
SA1, 0 Non-auto mode,
2-byte address field
Transparent mode 1
Recognition of TEI RFIFO
(last byte)
TA All except
transparent mode 0
Result of CRC check
(correct/incorrect)
RFIFO
(last byte)
CRC All
Valid Frame RFIFO
(last byte)
VFR All
Abort condition detected
(yes/no) RFIFO
(last byte)
RAB All
Data overflow during reception of a
frame (yes/no) RFIFO
(last byte)
RDO All
Message length RBC Reg. RBC11-0 All
RFIFO Overflow RBC Reg. OV All
C165H
IOM-2 Interface Controller
Data Sheet 338 2001-04-19
PRELIMINARY
- EXCERPT -
holds no further transmit data. This occurs if the host fails to respond to an XPR
interrupt quickly enough.
–XMR (Transmit Message Repeat) interrupt, indicating that the transmission of the
complete last frame has to be repeated as, for example, a collision on the S bus has
been detected.
Three different control commands are used for transmission of data:
–XTF (Transmit Transparent Frame) command, telling the HDLC controller that a word/
byte has been written to the TFIFO and should be transmitted. A start flag is generated
automatically.
–XME (Transmit Message End) command, telling the HDLC controller that the last data
written to the TFIFO completes the corresponding frame and should be transmitted.
This implies that according to the selected mode a frame end (CRC + closing flag) is
generated and appended to the frame.
–XRES (Transmitter Reset) command, resetting the HDLC transmitter and clearing the
transmit FIFO of any data.
Optionally one additional status conditions can be read by the host:
–XDOV (Transmit Data Overflow), indicating that the data block size has been
exceeded, i.e. CPU writes to an occupied TFIFO.
The TFIFO requests service from the microcontroller by setting a bit in the ISTAH
register, which causes an interrupt (XPR, XDU, XMR). The microcontroller can then read
the status register STAR (XDOV) and write data in the FIFO.
The instant of the initiation of a transmit pool ready (XPR) interrupt after different transmit
control commands is listed in Table 68.
When setting XME the transmitter appends the FCS and the endflag at the end of the
frame. When XTF & XME has been set, the TFIFO is locked until successful
transmission of the current frame, so a consecutive XPR interrupt also indicates
successful transmission of the frame whereas after XME or XTF the XPR interrupt is
Table 68 XPR Interrupt (availability of the TFIFO) after XTF, XME
Commands
CMDR. Transmit pool ready (XPR) interrupt initiated...
XTF as soon as the selected buffer size in the FIFO is available
XTF &
XME
after the successful transmission of the closing flag. The transmitter
sends always an abort sequence
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IOM-2 Interface Controller
Data Sheet 339 2001-04-19
PRELIMINARY
- EXCERPT -
asserted as soon as there is space for one data block in the TFIFO. Transmission in this
conjunction means the HDLC controller has send all data to the IOM-2 unit. The actual
transmission of the bits on the IOM-2 line can have some BCL cycles delay.
14.7.3.2 Possible Error Conditions during Transmission of Frames
If the transmitter sees an empty FIFO, i.e. if the microcontroller does not react quickly
enough to an XPR interrupt, an XDU (transmit data underrun) interrupt will be raised. If
the HDLC channel becomes unavailable during transmission the transmitter tries to
repeat the current frame as specified in the LAPD protocol. This is impossible after the
first data block has been sent (8 bytes), in this case an XMR transmit message repeat
interrupt is set and the microcontroller has to send the whole frame again.
Both XMR and XDU interrupts cause a reset of the TFIFO. The TFIFO is locked while an
XMR or XDU interrupt is pending, i.e. all write actions of the microcontroller will be
ignored as long as the microcontroller has not read the ISTAH register with the set XDU,
XMR interrupts.
If the microcontroller writes to a full FIFO, the data in the TFIFO will be corrupted and the
STAR.XDOV bit is set. If this happens, the microcontroller has to abort the transmission
by CMDR.XRES and to restart.
14.7.3.3 Transmit Frame Structure
The transmission of transparent frames (XTF command) is shown in Figure 123.
For transparent frames, the whole frame including address and control field must be
written to the TFIFO. The host configures whether the CRC is generated and appended
to the frame (default) or not (selected in MODEH.XCRC).
Furthermore, the host selects the interframe time fill signal which is transmitted between
HDLC frames (MODEH:ITF). One option is to send continuous flags (’01111110’),
however if D-channel access handling is required, the signal must be set to idle
(continuous ’1’s are transmitted).
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IOM-2 Interface Controller
Data Sheet 340 2001-04-19
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Figure 123 Transmit Data Flow
14.7.4 General Access to IOM-2 Channels
By setting the IOMSEL enable bits (EN_D1, EN_D2, EN_B1, EN_B2) in the IOMSEL
register the HDLC controller can access each of the four IOM-2 channels (B1, B2, D1,
D2) or any combination of them (e.g. 18 bit IDSL data (2B+D)) at a time). In all modes
sending works always frame aligned, i.e. it starts with the first selected channel whereas
reception looks for a flag anywhere in the serial data stream.
The Hardware is checking that no two HDLC controller have access to the same IOM-2
channel. This is done according to following priority:
– Channel 0 ... highest priority
– .....
– Channel 3 ... lowest priority.
IOM-2 channels (B1, B2, D1, D2), which are already allocated by higher prioritized HDLC
controller can not be used by a HDLC channel with lower priority.
If an IOM-2 channel is enabled for lower prioritized HDLC channel and this IOM-2
channel is also enabled for a higher prioritized HDLC channel than the enabling for the
lower prioritized HDLC channel is reseted.
14.7.5 Extended Transparent Mode
This non-HDLC mode is selected by setting MODE2...0 to ’100’. In extended transparent
mode fully transparent data transmission/reception without HDLC framing is performed
i.e. without FLAG generation/recognition, CRC generation/check, bitstuffing mechanism.
This allows user specific protocol variations.
FLAG
fifoflow_tran.vsd
Transmit Transparent Frame
(XTF)
CTRL CRC FLAGI
ADDRESS CONTROL DATA CHECKRAM
ADDR
*
1)
XFIFO
*
1)
The CRC is generated by default.
If MODEH.XCRC is set no CRC is appended
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IOM-2 Interface Controller
Data Sheet 341 2001-04-19
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- EXCERPT -
14.7.5.1 Transmitter
The transmitter sends the data out of the FIFO without manipulation. Transmission is
always IOM-frame aligned and byte aligned, i.e. transmission starts in the first selected
channel (B1, B2, D1, D2, according to the setting of register IOMSEL in the IOM Handler)
of the next IOM frame.
The FIFO indications and commands are the same as in other modes.
If the CPU sets XTF & XME the transmitter responds with an XPR interrupt after sending
the last byte, then it returns to its idle state (sending continuous ‘1’).
If the collision detection is enabled (CIC_CMD.DIM = ’0x1’) the stop go bit (S/G) can be
used as clear to send indication as in any other mode. If the S/G bit is set to ’1’ (stop)
during transmission the transmitter responds always with an XMR (transmit message
repeat) interrupt.
If the microcontroller fails to respond to a XPR interrupt in time and the transmitter runs
out of data then it will assert an XDU (transmit data underrun) interrupt.
14.7.5.2 Receiver
The reception is IOM-frame aligned and byte aligned, like transmission, i.e. reception
starts in the first selected channel (B1, B2, D1, D2, according to the setting of register
IOMSEL in the IOM Handler) of the next IOM frame. The FIFO indications and
commands are the same as in others modes.
All incoming data bytes are stored in the RFIFO and additionally made available in
STAR. If the FIFO is full an RFO interrupt is asserted (MODEH.SRA = ’0’).
Note: In the extended transparent mode the MODEH register bits has to be set to
SRA = ’0’, XCRC = ’0’, RCRC = ’0’ and IFF = ’0’.
14.7.6 HDLC Controller Interrupts
14.7.6.1 General HDLC Interrupt
The cause of an interrupt related to the HDLC controller (except FIFO R/W) is indicated
by the HDLC bit in the ISTA register. This bit points at the different interrupt sources of
the HDLC controller part in the ISTAH register. The individual interrupt sources of the
HDLC controller during reception and transmission of data are explained the related
chapters.
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IOM-2 Interface Controller
Data Sheet 342 2001-04-19
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- EXCERPT -
Figure 124 Interrupt Status Registers of the HDLC Controller
Each interrupt source in ISTAH register can be selectively masked by setting to “1” the
corresponding bit in MASKH.
All these interrupts (XDOV, FFO, RME, RFO, XMR, XDU) are acknowledged by writing
’1’ to the ISTAH register.
14.7.6.2 HDLC Transmit/Receive FIFO Interrupt
The RPF/XPR interrupt indicates that data can be read from RFIFO written to the TFIFO.
To enable a fast action upon these interrupts there are two possibilities:
1. Via the general interrupt line: The interrupt source (ISTAH, XPR; ISTAH, RPF) is
(masked) mapped to the corresponding bit in the ISTA register
2. Using a direct interrupt line: For HDLC controller 0 and 1 the XPR/RPF interrupts are
mapped directly to individual interrupt lines. These lines are masked by the bits
MODEH.XPE and MODEH.RPE. The direct interrupt lines can be used for PEC
handling of these interrupts.
The XPR and RPF interrupts do not need to be acknowledged. The acknowledgment is
done implicit in a read/write access to the specific FIFO.
RME
RFO
XMR
XDU
CIC
ST
MOS
RME
RFO
XMR
XDU
MASKH ISTAH
4x
IOMINT
ISTAMASK
CIC
ST
MOS
HDLC
4x
HDLC
4x
4x
4x
RPF
RPF
XPR
XPR
RPF
RPF
XPR
4x
XPR
4x
XDOV
FFO
XDOV
FFO
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IOM-2 Interface Controller
Data Sheet 343 2001-04-19
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14.7.6.3 Interrupt Generation
The source of each interrupt is, in general, a static signal. These signals are masked and
propagated. A rising edge detection and pulse generation unit is placed at the output of
each of the five IOM-2 interrupts. This results in the generation of a new interrupt if the
IOMINT line has been changed from ’0’ to ’1’. This can occur:
• If an interrupt occurs
• By setting all mask bits and resetting them again
14.8 IOM-2/HDLC Controller Register Set
This section summarizes all registers, which are implemented in the IOM-2 module of
the C165H and explains the description format.
14.8.1 Register Description Format
In the respective chapters the function and layout of the registers is described in a
specific format which provides a number of deteils about the described register. The
example below shows how to interpret these details.
A register looks like this:
REG_LONG_NAME
Elements:
• REG_NAME: short name of the register
• REG_NAME_LONG: long name of the register
• Address: 8 bit address given in hex format, relative to the base address of the IOM-2
registers.
• Field: name of a bitfiled within the register.
Name: Address: 00H
Name: Name: REG_NAME
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Field Bits Type Value Description
BITFIELD_NAME 10:0 R/W 0 BITFIELD_LONG_NAME
TEXT++ TEXT++ TEXT
RESERVED 15:11 These bits are reserved
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Data Sheet 344 2001-04-19
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• Bits: the exact bits the bitfield occupies.
• Type: (R, W, R/W)= this bit is (only readable, only writable, read and writable) form the
CPU.
• Description: contains the long name for the bitfield and further description.
• Value: the reset value of the bitfield.
Note: All reset values for bitfields of one bit length are given in binary form 0/1. For
bitfields with more than one bit length they are given in decimal notation. For
example, a four bit address name 3:0 with reset value ’12’ must read ’1100’ in
binary notation. Exceptions are marked with the subscript charackter ’H’ for hex
values. In this case, hex values reads always ’(bitfield length-1) downto 0’.
Note: Bitfields marked as RESERVED may be used in further versions and their
functionality is not guaranteed. They do not have any Type or Value specification.
14.8.2 Register Table ordered by Address
The following table lists all registers in the C165H IOM-2 module ordered by their
physical address. The address is an 8-bit address which is relative to the IOM-2 base
address.
The base address for the IOM-2 registers is 00EF00H.
Table 69 IOM-2 Register Set ordered by Address
00EF00H + ... Register Function
00HIOMCLC IOM-2 Clock Control Register
02HRESERVED
04HRESERVED
06HRESERVED
08HIOMID IOM-2 Identification Register
0AHRESERVED
0CHRESERVED
0EHRESERVED
10HCDA_10 Controller Data Access Register 10
12HCDA_11 Controller Data Access Register 11
14HCDA_20 Controller Data Access Register 21
16HCDA_21 Controller Data Access Register 22
18HCDA_TSDP10 Time Slot and Data Port Selection for CDA 10
1AHCDA_TSDP11 Time Slot and Data Port Selection for CDA 11
1CHCDA_TSDP20 Time Slot and Data Port Selection for CDA 20
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IOM-2 Interface Controller
Data Sheet 345 2001-04-19
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1EHCDA_TSDP21 Time Slot and Data Port Selection for CDA 21
20HB1_TSDP Time Slot and Data Port Selection for B1
22HB2_TSDP Time Slot and Data Port Selection for B2
24HD1_TSDP Time Slot and Data Port Selection for D1
26HD2_TSDP Time Slot and Data Port Selection for D2
28HRESERVED
2AHRESERVED
2CHRESERVED
2EHRESERVED
30HISTA Interrupt Status Register
32HMASK Interrupt Mask Register
34HCDA1_CR Control Register for CDA Channel 1
36HCDA2_CR Control Register for CDA Channel 2
38HCIC_CR Control Register for Control/Indication Channel
3AHMON_CR Control Register for Monitor Channel
3CHIOM_CR Control Register for IOM Interface
3EHRESERVED
40HSTI Synchronous Transfer Interrupt
42HMSTI Mask Synchronous Transfer Interrupt
44HASTI Acknowledge Synchronous Transfer Interrupt
46HRESERVED
48HRESERVED
4AHRESERVED
4CHRESERVED
4EHRESERVED
50HMOR Monitor Receive Channel
52HMOX Monitor Transmit Channel
54HMOCR Monitor Control Register
56HMSTA Monitor Status Register
58HMOSR Monitor Interrupt Status Register
5AHMCDA MCDA - Monitoring CDA Bits
5CHRESERVED
5EHRESERVED
Table 69 IOM-2 Register Set ordered by Address (cont’d)
00EF00H + ... Register Function
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IOM-2 Interface Controller
Data Sheet 346 2001-04-19
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60HCIC0_D Command/Indication Channel 0 Data
62HCIC1_D Command/Indication Channel 1 Data
64HCIC_CMD Command/Indication Channel Command Register
66HCIC_ST Command/Indication Channel Status Register
68HDCSI DCL Clock Supervision Interval
6AHRESERVED
6CHRESERVED
6EHRESERVED
70HRESERVED
72HRESERVED
74HRESERVED
76HRESERVED
78HRESERVED
7AHRESERVED
7CHRESERVED
7EHRESERVED
80HRFIFO_0 Receive FIFO (HDLC-Channel 0)
82HTFIFO_0 Transmit FIFO (HDLC-Channel 0)
84HISTAH_0 Interrupt Status Register (HDLC-Channel 0)
86HMASKH_0 Interrupt Mask Register (HDLC-Channel 0)
88HSTAR_0 Status Register (HDLC-Channel 0)
8AHCMDR_0 Command Register (HDLC-Channel 0)
8CHIOMSEL_0 IOM-2 Channel Selection (HDLC-Channel 0)
8EHMODEH_0 Mode Register (HDLC-Channel 0)
90HSAP1_0 SAPI1 Register (HDLC-Channel 0)
92HSAP2_0 SAPI2 Register (HDLC-Channel 0)
94HRBC_0 Receive Frame Byte Count (HDLC-Channel 0)
96HTEI1_0 TEI1 Register (HDLC-Channel 0)
98HTEI2_0 TEI2 Register (HDLC-Channel 0)
9AHLOOPH_0 Looping Register (HDLC-Channel 0)
9CHRESERVED
9EHRESERVED
A0HRFIFO_1 Receive FIFO (HDLC-Channel 1)
Table 69 IOM-2 Register Set ordered by Address (cont’d)
00EF00H + ... Register Function
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IOM-2 Interface Controller
Data Sheet 347 2001-04-19
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- EXCERPT -
A2HTFIFO_1 Transmit FIFO (HDLC-Channel 1)
A4HISTAH_1 Interrupt Status Register (HDLC-Channel 1)
A6HMASKH_1 Interrupt Mask Register (HDLC-Channel 1)
A8HSTAR_1 Status Register (HDLC-Channel 1)
AAHCMDR_1 Command Register (HDLC-Channel 1)
ACHIOMSEL_1 IOM-2 Channel Selection (HDLC-Channel 1)
AEHMODEH_1 Mode Register (HDLC-Channel 1)
B0HSAP1_1 SAPI1 Register (HDLC-Channel 1)
B2HSAP2_1 SAPI2 Register (HDLC-Channel 1)
B4HRBC_1 Receive Frame Byte Count (HDLC-Channel 1)
B6HTEI1_1 TEI1 Register (HDLC-Channel 1)
B8HTEI2_1 TEI2 Register (HDLC-Channel 1)
BAHLOOP_1 Looping Register (HDLC-Channel 1)
BCHRESERVED
BEHRESERVED
C0HRFIFO_2 Receive FIFO (HDLC-Channel 2)
C2HTFIFO_2 Transmit FIFO (HDLC-Channel 2)
C4HISTAH_2 Interrupt Status Register (HDLC-Channel 2)
C6HMASKH_2 Interrupt Mask Register (HDLC-Channel 2)
C8HSTAR_2 Status Register (HDLC-Channel 2)
CAHCMDR_2 Command Register (HDLC-Channel 2)
CCHIOMSEL_2 IOM-2 Channel Selection (HDLC-Channel 2)
CEHMODEH_2 Mode Register (HDLC-Channel 2)
D0HSAP1_2 SAPI1 Register (HDLC-Channel 2)
D2HSAP2_2 SAPI2 Register (HDLC-Channel 2)
D4HRBC_2 Receive Frame Byte Count (HDLC-Channel 2)
D6HTEI1_2 TEI1 Register (HDLC-Channel 2)
D8HTEI2_2 TEI2 Register (HDLC-Channel 2)
DAHLOOP_2 Looping Register (HDLC-Channel 2)
DCHRESERVED
DEHRESERVED
E0HRFIFO_3 Receive FIFO (HDLC-Channel 3)
E2HTFIFO_3 Transmit FIFO (HDLC-Channel 3)
Table 69 IOM-2 Register Set ordered by Address (cont’d)
00EF00H + ... Register Function
C165H
IOM-2 Interface Controller
Data Sheet 348 2001-04-19
PRELIMINARY
- EXCERPT -
E4HISTAH_3 Interrupt Status Register (HDLC-Channel 3)
E6HMASK_3 Interrupt Mask Register (HDLC-Channel 3)
E8HSTAR_3 Status Register (HDLC-Channel 3)
EAHCMDR_3 Command Register (HDLC-Channel 3)
ECHIOMSEL_3 IOM-2 Channel Selection (HDLC-Channel 3)
EEHMODEH_3 Mode Register (HDLC-Channel 3)
F0HSAP1_3 SAPI1 Register (HDLC-Channel 3)
F2HSAP2_3 SAPI2 Register (HDLC-Channel 3)
F4HRBC_3 Receive Frame Byte Count (HDLC-Channel 3)
F6HTEI1_3 TEI1 Register (HDLC-Channel 3)
F8HTEI2_3 TEI2 Register (HDLC-Channel 3)
FAHLOOP_3 Looping Register (HDLC-Channel 3)
FCHRESERVED
FEHRESERVED
Table 69 IOM-2 Register Set ordered by Address (cont’d)
00EF00H + ... Register Function
C165H
IOM-2 Interface Controller
Data Sheet 349 2001-04-19
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14.8.3 Detailed Register Description ordered by Address
IOM-2 Clock Control Register
The register IOMCLC is clocked with the bus clock to be able to switch the IOM-2
interface controller clock on again, if it was off. If required, switching off the clock can be
prevented by the IOM-2 controller.
Address: 00H
Name: IOMCLC
151413121110987654 3210
Reserved IOM
EX_DIS
IOM
GPSEN
IOM
DIS
IOM
DISR
Field Bits Type Value Description
IOMEX_DIS 3 R/W 0 IOM-2 Controller Clock Disable
0: The clock of the IOM-2 interface
controller is enabled, normal operation.
1: The clock of the IOM-2 interface
controller is disabled.
IOMGPSEN 2 R/W 0 IOM-2 Controller Clock OCDS Disable
0: The clock of the IOM-2 interface
controller is enabled, normal operation.
1: The clock of the IOM-2 interface
controller is disabled during debugging
mode (OCDS)
IOMDIS 1 R 0 IOM-2 Controller Clock Status
0: The status of the IOM-2 interface
controller clock is ’enabled’.
1: The status of the IOM-2 interface
controller clock is ’disabled’.
IOMDISR 0 R/W 0 IOM-2 Controller Clock Disable
0: The clock of the IOM-2 interface
controller is enabled, normal operation.
1: The clock of the IOM-2 interface
controller is disabled.
RESERVED 15:4 - 0 These bits are reserved
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IOM-2 Interface Controller
Data Sheet 350 2001-04-19
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The state of the IOM-2 interface controller clock is controlled by the register bit
IOMDISR. The actual clock state will be shown by the state bit IOMDIS.
For on chip debugging support (OCDS) an additional bit IOMGPSEN is introduced to
stop the peripheral clock for arbitrary lengths of time during debugging if this function is
enabled. If debugging mode is active, the peripheral core rejects write access to
registers connected to the peripheral clock.
To be compatible with previous C16x products an IOMEX_DISR signal is provided to
disable the peripheral clock.
IOM-2 Identification Register
Controller Data Access Register xy (x=1,2; y =0,1)
Name: 08H
Name: IOMID
1514131211109876543210
ID
Field Bits Type Value Description
ID 15:0 R 0 IOM-2 Identification Register
Address: 10H 12H 14H 16H
Name: CDA_10 CDA_11 CDA_20 CDA_21
1514131211109876543210
RESERVED CDA_xy
Field Bits Type Value Description
CDA_xy 7:0 R/W FFHData register which can be accessed
from the CPU.
RESERVED 15:8 R These bits are reserved.
C165H
IOM-2 Interface Controller
Data Sheet 351 2001-04-19
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Time Slot and Data Port Selection for CDA_xy (x=1,2; y =0,1)
This register determines the time slots and the data ports on the IOM-2 Interface for the
data channels xy of the functional unit CDA (Controller Data Access).
Note: For the CDA (controller data access) data the input is determined by the
CDA_CRx.SWAP bit. If SWAP = ‘0’ the input for the CDAxy data is vice versa to
the output setting for CDAxy. If the SWAP = ‘1’ the input from CDAx0 is vice versa
to the output setting of CDAx1 and the input from CDAx1 is vice versa to the output
setting of CDAx0. See controller data access description in Chapter 14.5.
Address: 18H 1AH 1CH 1EH
Address: CDA_TSDP10 CDA_TSDP11 CDA_TSDP20 CDA_TSDP21
1514131211109876543210
DPS RESERVED TSS
Field Bits Type Value Description
DPS(10)
(11)
(20)
(21)
15 R/W 0
0
1
1
Data Port Selection
0: The data channel xy of the functional
unit CDA is output on DD and input
from DU.
1: The data channel xy of the functional
unit CDA is output on DU and input
from DD.
TSS(10)
(11)
(20)
(21)
4:0 R/W 0
1
0
1
Time Slot Selection
Selects one of 32 timeslots (0..31) of the
IOM-Interface for the data channels.
RESERVED 14:5 R These bits are reserved.
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IOM-2 Interface Controller
Data Sheet 352 2001-04-19
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Time Slot and Data Port Selection for the 8-bit HDLC Channel B1
Time Slot and Data Port Selection for the 8-bit HDLC Channel B2
Address: 20H
Name: B1_TSDP
1514131211109876543210
DPS RESERVED TSS
Field Bits Type Value Description
DPS 15 W 0 Data Port Selection
0: The data of the 8-bit HDLC channel B1
is output on DD and input from DU.
1: The data of the first 8-bit HDLC
channel B1 is input from DD and output
on DU.
TSS 4:0 W 0 Time Slot Selection
Selects one of 32 timeslots (0..31) of the
IOM-Interface for the 8-bit HDLC channel
B1.
RESERVED 14:5 R These bits are reserved.
Address: 22H
Name: B2_TSDP
1514131211109876543210
DPS RESERVED TSS
Field Bits Type Value Description
DPS 15 W 0 Data Port Selection
0: The data of the 8-bit HDLC channel B2
is output on DD and input from DU.
1: The data of the 8-bit HDLC channel
B2 is input from DD and output on DU.
TSS 4:0 W 0 Time Slot Selection
Selects one of 32 timeslots (0..31) of the
IOM-Interface for the 8-bit HDLC channel
B2.
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IOM-2 Interface Controller
Data Sheet 353 2001-04-19
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Time Slot and Data Port Selection for the 2-bit HDLC Channel D1
Note: D1 channel access always starts with bit 7 (MSB) on the IOM/PCM timeslot.
RESERVED 14:5 R 0 These bits are reserved.
Address: 24H
Name: D1_TSDP
1514131211109876543210
DPS RESERVED TSS
Field Bits Type Value Description
DPS 15 W 0 Data Port Selection
0: The data of the 2-bit HDLC channel
D1 is output on DD and input from DU.
1: The data of the 2-bit HDLC channel
D1 is input from DD and output on DU.
TSS 4:0 W 0 Time Slot Selection
Selects one of 32 timeslots (0..31) of the
IOM-Interface for the 2-bit HDLC channel
D1.
RESERVED 14:5 R 0 These bits are reserved.
Field Bits Type Value Description
C165H
IOM-2 Interface Controller
Data Sheet 354 2001-04-19
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Time Slot and Data Port Selection for the 2-bit HDLC Channel D2
Note: D2 channel access always starts with bit 7 (MSB) on the IOM/PCM timeslot.
Interrupt Status Register
Address: 26H
Name: D2_TSDP
1514131211109876543210
DPS RESERVED TSS
Field Bits Type Value Description
DPS 15 W 0 Data Port Selection
0: The data of the 2-bit HDLC channel
D2 is output on DD and input from DU.
1: The data of the 2-bit HDLC channel
D2 is input from DD and output on DU.
TSS 4:0 W 0 Time Slot Selection
Selects one of 32 timeslots (0..31) of the
IOM-Interface for the 2-bit HDLC channel
D2.
RESERVED 14:5 R 0 These bits are reserved.
Address: 30H
Name: ISTA
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RPF
3
RPF
2
RPF
1
RPF
0
XPR
3
XPR
2
XPR
1
XPR
0DCSI ST CIC MOS HDLC
3
HDLC
2
HDLC
1
HDLC
0
Field Bits Type Value Description
HDLC3..0 3:0 R 0 HDLC Channel Interrupts
The HDLC controller (0..3) has one of the
following interrupt sources: RME, RFO, FFO,
XMR, XDU, or XDOV.
MOS 4 R 0 Monitor Status
A change in the MONITOR Status Register
(MOSR) has occured.
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IOM-2 Interface Controller
Data Sheet 355 2001-04-19
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- EXCERPT -
Note: DCSI is the only physical flip flop in the ISTA register. All other bits are multiplexed
from different sources in the IOM-2 unit.
For all interrupts in the ISTA register the following states are applied:
0: Interrupt is not activated
1: Interrupt is activated
CIC 5 R 0 C/I Channel Change
A change in C/I channel 0 or C/I channel 1
has been recognized. The actual value can be
read from CIC_ST.
ST 6 R 0 Synchronous Transfer
When programmed (STI register), this
interrupt is generated to enable the
microcontroller to lock on to the IOM timing,
for synchronous transfers.
DCSI 7 R 0 DCL Clock STATUS Interrupt
A change in the CIC_ST.DCOD (DCL Clock
Off Detection) STATUS flag has occured.
XPR3..0 11:8 R 0 Transmit Pool Ready for HDLC channel x
(x = 0..3)
This is the masked / unmasked XPR interrupt
from ISTAH_x.XPR.
XPR is used for faster reaction of the SW to
the transmit FIFO interrupts.
RPF3..0 15:12 R 0 Receive Pool Full for HDLC channel x
(x = 0..3)
This is the masked/unmasked RPF interrupt
from ISTAH_x.RPF.
RPF is used for faster reaction of th SW to the
receive FIFO interrupts.
Field Bits Type Value Description
C165H
IOM-2 Interface Controller
Data Sheet 356 2001-04-19
PRELIMINARY
- EXCERPT -
Interrupt Mask Register
The MASK register is related to the ISTA register, page 354. Using the MASK register,
all interrupts of the ISTA register can be masked.
For all mask interrupts in the MASK register the following states are applied:
0: Interrupt is not masked
1: Interrupt is masked
Address: 32H
Name: MASK
1514131211109876543210
RPF
3
RPF
2
RPF
1
RPF
0
XPR
3
XPR
2
XPR
1
XPR
0DCSI ST CIC MOS HDLC
3
HDLC
2
HDLC
1
HDLC
0
Field Bits Type Value Description
HDLC3..0 3:0 R/W FHHDLC Channel x Interrupts Mask
MOS 4 R/W 1 Monitor Status Mask
CIC 5 R/W 1 C/I Channel Change Mask
ST 6 R/W 1 Synchronous Transfer Mask
DCSI 7 R/W 1 DCL Clock STATUS Interrupt Mask
XPR3..0 11:8 R/W FHTransmit Pool Ready for HDLC channel x
Mask
RPF3..0 15:12 R/W FHReceive Pool Full for HDLC channel x Mask
C165H
IOM-2 Interface Controller
Data Sheet 357 2001-04-19
PRELIMINARY
- EXCERPT -
Control Register for Controller Data Access CHx (x = 1,2)
Address: 34H36H
Name: CDA1_CR CDA2_CR
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RESERVED EN_I1 EN_I0 EN_O1 EN_O0 SWAP
Field Bits Type Value Description
EN_I1
EN_I0
4
3
R/W
R/W
0
0
Enable Input CDAx0, CDAx1
0: The input of the CDAx0, CDAx1
register is disabled
1: The input of the CDAx0, CDAx1
register is enabled
EN_O1
EN_O0
2
1
R/W
R/W
0
0
Enable Output CDAx0, CDAx1
0:The output of the CDAx0, CDAx1
register is disabled
1: The output of the CDAx0, CDAx1
register is enabled
SWAP 0 R/W 0 Swap Inputs
0: The time slot and data port for the
input of the CDAxy register is defined
by its own CDA_TSDPxy register.
The data port for the CDAxy input is
vice versa to the output setting for
CDAxy.
1: The input (time slot and data port) of
the CDAx0 is defined by the TSDP
register of CDAx1 and the input of
CDAx1 is defined by the TSDP
register of CDAx0. The data port for
the CDAx0 input is vice versa to the
output setting for CDAx1. The data
port for the CDAx1 input is vice versa
to the output setting for CDAx0. The
input definition for time slot and data
port CDAx0 are thus swapped to
CDAx1 and for CDAx1 to CDAx0.
The outputs are not affected by the
SWAP bit.
C165H
IOM-2 Interface Controller
Data Sheet 358 2001-04-19
PRELIMINARY
- EXCERPT -
Control Register for Control/Indication Channel
Address: 38H
Name: CIC_CR
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
DPS_C
I1
EN_CI
1RESERVED DPS_
CI0
EN_CI
0RESERVED
Field Bits Type Value Description
EN_CI0 6 R/W 0 Enable CI0 Data
0: CI0 data is disabled
1: CI0 data is enabled
DPS_CI0 7 R/W 1 Data Port Selection CI0 Data
0: The CI0 data is output on DD and
input from DU
1: The CI0 data is output on DU and
input from DD
EN_CI1 14 R/W 0 Enable CI1 Data
0: CI1 data is disabled
1: CI1 data is enabled
DPS_CI1 15 R/W 1 Data Port Selection CI1 Data
0: The CI1 data is output on DD and
input from DU
1: The CI1 data is output on DU and
input from DD
Reserved 13:8,
5:0
R These bits are reserved
C165H
IOM-2 Interface Controller
Data Sheet 359 2001-04-19
PRELIMINARY
- EXCERPT -
Control Register for Monitor Channel
Address: 3AH
Name: MON_CR
1514131211109876543210
EN_M
ON RESERVED DPS RESERVED MCS
Field Bits Type Value Description
EN_MON 15 R/W 1 Enable Output
0: The Monitor data input and output is
disabled
1: The Monitor data input and output is
enabled
DPS 7 R/W 0 Data Port Selection
0: The Monitor data is output on DD and
input from DU
1: The Monitor data is output on DU and
input from DD
MCS 2:0 R/W 0 Monitor Channel Selection
000: The MONITOR data is input/output
on MON0 (3rd timeslot on IOM-2)
001: The MONITOR data is input/output
on MON1 (7th timeslot on IOM-2)
010: The MONITOR data is input/output
on MON2 (11th timeslot on IOM-2)
...
111: The MONITOR data is input/output
on MON7 (31st timeslot on IOM-2)
Reserved 14:8,
6:3
R These bits are reserved
C165H
IOM-2 Interface Controller
Data Sheet 360 2001-04-19
PRELIMINARY
- EXCERPT -
Control Register for the IOM-2 Interface
Address: 3CH
Name: IOM_CR
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RESERVED SPU DIS_OD CLKM DIS_IOM
Field Bits Type Value Description
DIS_IOM 0 R/W 0 Disable IOM
DIS_IOM should b set to ’1’ if external
devices connected to the IOM interface
should be ’disconnected’, e.g. for power
savings purposes.
0: The IOM interface is enabled
1: The IOM interface is disabled (high
impendance)
CLKM 1 R/W 0 Clock Mode
0: A double bit clock is connected to DCL
1: A single bit clock is connected to DCL
DIS_OD 2 W/R 0 Open_Drain
0: IOM outputs are open drain driver
1: IOM outputs are push pull driver
SPU 3 R/W 0 Software Power UP
0: The DU line is normally used for trans
mitting data.
1: Setting this bit to ’1’ will pull the DU
line to low. This will enforce con-
nected layer 1 devices to deliver IOM-
clocking.
After a subsequent ISTA:CIC-interrupt (C/
I-code change) and reception of the C/I-
code ”PU” (Power Up indication in TE-
mode) the user has to write an AR or TIM
command as C/I-code in the CIX0-
register, resets the SPU bit and waits for
the following CIC-interrupt.
Reserved 15:4 R These bits are reserved
C165H
IOM-2 Interface Controller
Data Sheet 361 2001-04-19
PRELIMINARY
- EXCERPT -
Synchronous Transfer Interrupt
For all interrupts in the STI register following logical states are applied:
0:Interrupt is not acitvated
1:Interrupt is acitvated
Note: ST0Vxy and ACKxy are useful for synchronizing microcontroller accesses and
receive/transmit operations. One BCL clock is equivalent to two DCL clocks.
Address: 40H
Name: STI
151413121110987 6543210
Reserved STOV
21
STOV
20
STOV
11
STOV
10
STI
21
STI
20
STI
11
STI
10
Field Bits Type Value Description
STOV21
STOV20
STOV11
STOV10
7
6
5
4
R
R
R
R
0
0
0
0
Synchronous Transfer Overflow
Interrupt
Enabled STOV interrupts for a certain
STIxy interrupt are generated when the
STIxy has not been acknowledged in
time via the ACKxy bit in the ASTI
register. This must be one (for DPS=’0’)
or zero (for DPS=’1’) BCL clocks before
the time slot which is selected for the
STOV.
STI21
STI20
STI11
STI10
3
2
1
0
R
R
R
R
0
0
0
0
Synchronous Transfer Interrupt
Depending on the DPS bit in the
corresponding TSDPxy register the
Synchronous Transfer Interrupt STIxy is
generated two (for DPS=’0’) or one (for
DPS=’1’) BCL clock after the selected
time slot (TSDPxy.TSS).
Reserved 15:8 R 0 These bits are reserved
C165H
IOM-2 Interface Controller
Data Sheet 362 2001-04-19
PRELIMINARY
- EXCERPT -
Mask Synchronous Transfer Interrupt
For the MSTI register following logical states are applied:
0:Interrupt is not masked
1:Interrupt is masked
Address: 42H
Name: MSTI
151413121110987 6543210
Reserved STOV
21
STOV
20
STOV
11
STOV
10
STI
21
STI
20
STI
11
STI
10
Field Bits Type Value Description
STOV21
STOV20
STOV11
STOV10
7
6
5
4
R/W
R/W
R/W
R/W
1
1
1
1
Synchronous Transfer Overflow for
STIxy
By masking the STOV bits the number
and time of the STOV interrupts for a
certain enabled STIxy interrupt can be
controlled. For an enabled STIxy the own
STOVxy is generated when the STOVxy
is enabled (MSTI.STIxy and
MSTI.STOVxy = ’0’). Additionally all
other STOV interrupts of which the
corresponding STI is disabled (MSTI.STI
= ’1’ and MSTI.STOV = ’0’) are
generated.
STI21
STI20
STI11
STI10
3
2
1
0
R/W
R/W
R/W
R/W
1
1
1
1
Synchronous Transfer Interrupt xy
The STIxy interrupts can be masked by
setting the corresponding mask bit to ’1’.
For a masked STIxy no STOV interrupt is
generated.
Reserved 15:8 R 0 These bits are reserved
C165H
IOM-2 Interface Controller
Data Sheet 363 2001-04-19
PRELIMINARY
- EXCERPT -
Acknowledge Synchronous Transfer Interrupt
Monitor Receive Channel
Address: 44H
Name: ASTI
151413121110987 6543210
Reserved ACK
21
ACK
20
ACK
11
ACK
10
Field Bits Type Value Description
ACK21
ACK20
ACK11
ACK10
3
2
1
0
W
W
W
W
0
0
0
0
Acknowledge Synchronous Transfer
Interrupt
After a STIxy interrupt the microcontroller
has to acknowledge the interrupt by
setting the corresponding ACKxy bit.
0: No activity is initiated
1: Sets the acknowledge bit ACKxy for a
STIxy interrupt
Reserved 15:4 R 0 These bits are reserved
Address: 50H
Name: MOR
151413121110987 6543210
RESERVED MOR
Field Bits Type Value Description
MOR 7:0 R FF MONITOR Data Received
Contains the MONITOR data received in
the IOM-2 MONITOR channel according
to the MONITOR channel protocol. The
MONITOR channel (0 ... 7) can be
selected by setting the monitor channel
select bits MON_CR.MCS.
C165H
IOM-2 Interface Controller
Data Sheet 364 2001-04-19
PRELIMINARY
- EXCERPT -
Monitor Transmit Channel
Monitor Control Register
Reserved 15:8 R 0 These bits are reserved
Address: 52H
Name: MOX
151413121110987 6543210
RESERVED MOX
Field Bits Type Value Description
MOX 7:0 W FF MONITOR Data Transmitted
Contains the MONITOR data to be
transmitted in IOM-2 MONITOR channel
according to the MONITOR channel
protocol.The MONITOR channel (0 ... 7)
can be selected by setting the monitor
channel select bits MON_CR.MCS
Reserved 15:8 R 0 These bits are reserved
Address: 54H
Name: MOCR
151413121110987 6543210
RESERVED MRE MRC MIE MXC
Field Bits Type Value Description
MRE 3 R/W 0 MONITOR Receive Interrupt Enable
0: MONITOR interrupt status MDR
generation is masked
1: MONITOR interrupt status MDR
generation is enabled
Field Bits Type Value Description
C165H
IOM-2 Interface Controller
Data Sheet 365 2001-04-19
PRELIMINARY
- EXCERPT -
Monitor Status Register
MRC 2 R/W 0 MR Bit Control
Determines the value of the MR bit:
0: MR is always ’1’. In addition, the MDR
interrupt is blocked, except for the first
byte of a packet (if MRE = 1).
1: MR is internally controlled according to
the MONITOR channel protocol. In
addition, the MDR interrupt is enabled
for all received bytes according to the
MONITOR channel protocol (if
MRE = ’1’).
MIE 1 R/W 0 MONITOR Interrupt Enable
MONITOR interrupt status MER, MDA,
MAB generation is enabled (1) or
masked (0).
MXC 0 R/W 0 MX Bit Control
Determines the value of the MX bit:
0: The MX bit is always ’1’.
1: The MX bit is internally controlled
according to the MONITOR channel
protocol.
Reserved 15:4 R 0 These bits are reserved
Address: 56H
Name: MSTA
151413121110987 6543210
MAC RESERVED
Field Bits Type Value Description
MAC 15 R 0 MONITOR Transmit Channel Active
The data transmisson in the MONITOR
channel is in progress
Reserved 14:0 R 0 These bits are reserved
Field Bits Type Value Description
C165H
IOM-2 Interface Controller
Data Sheet 366 2001-04-19
PRELIMINARY
- EXCERPT -
Monitor Interrupt Status Register
Note: These interrupt status bits can be polled, i.e. a ’Read’ does not reset these
interrupts. To reset a specific interrupt a ’1’ must be written to the specific interrupt
bit.
Monitoring CDA Bits
Address: 58H
Name: MOSR
151413121110987 6543210
RESERVED MDR MER MDA MAB
Field Bits Type Value Description
MDR 3 R/W 0 MONITOR channel Data Received
MER 2 R/W 0 MONITOR channel End of Reception
MDA 1 R/W 0 MONITOR Channel Data Acknowledge
The remote end has acknowledged the
MONITOR byte being transmitted.
MAB 0 R/W 0 MONITOR Channel Data Abort
Reserved 15:4 R 0 These bits are reserved
Address: 5AH
Name: MCDA
151413121110987 6543210
RESERVED MCDA21 MCDA20 MCDA11 MCDA10
Field Bits Type Value Description
MCDA21
MCDA20
MCDA11
MCDA10
7:6
5:4
3:2
1:0
R
R
R
R
03
03
03
03
Monitoring CDAxy Bits
Bit 7 and Bit 6 of the CDAxy registers are
mapped into the MCDA register. This can
be used for monitoring the D-channel bits
on DU and DD and the ’Echo bits’ on the
TIC bus with the same register.
C165H
IOM-2 Interface Controller
Data Sheet 367 2001-04-19
PRELIMINARY
- EXCERPT -
Command/Indication Channel 0 Data
Note: The CODR0 bits are updated every time a new C/I-code is detected in two
consecutive IOM-frames. If several consecutive valid new codes are detected and
CIR0 is not read, only the first and the last C/I code is made available in CODR0
at the first and second read of that register, respectively.
Reserved 15:4 R 00 These bits are reserved
Address: 60H
Name: CIC0_D
151413121110987 6543210
RESERVED CODR0 RESERVED CODX0
Field Bits Type Value Description
CODX0 3:0 W FHC/I-Code 0 Transmit
Code to be transmitted in the C/I-channel
0.
CODR0 11:8 R FHC/I Code 0 Receive
Value of the received Command/
Indication code. A C/I-code is loaded in
CODR0 only after being the same in two
consecutive IOM-frames and the previous
code has been read from CIR0.
Reserved 15:12,
7:4
R0
HThese bits are reserved
Field Bits Type Value Description
C165H
IOM-2 Interface Controller
Data Sheet 368 2001-04-19
PRELIMINARY
- EXCERPT -
CIC1_D - Command/Indication Channel 1 Data
Command/Indication Channel Command Register
Address: 62H
Name: CIC1_D
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RESERVED CODR1 RESERVED CODX1
Field Bits Type Value Description
CODX1 5:0 W 3FHC/I-Code 1 Transmit
Bits 7-2 of C/I-channel 1
CODR1 13:8 R 3FHC/I-Code 1 Receive
Value of the received Command/
Indication code.
Reserved 15,14
7,6
R’00’These bits are reserved
Address: 64H
Name: CIC_CMD
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RESERVED DIM
RES
ERV
ED
TIC_
DIS CI1E CICW BAC TBA
Field Bits Type Value Description
TBA 2:0 W 7 TIC Bus Address
Defines the individual address for the
C165H on the IOM-2 bus.
This address is used to access the C/I-
and D-channel on the IOM interface.
Note: If only one device is liable to
transmit in the C/I- and D-channels
of the IOM it should always be given
the address value "111".
C165H
IOM-2 Interface Controller
Data Sheet 369 2001-04-19
PRELIMINARY
- EXCERPT -
BAC 3 W 0 Bus Access Control
Only valid if the TIC-bus feature is enabled
(MODE:DIM2-0).
If this bit is set, the C165H will try to
access the TIC-bus to occupy the C/I-
channel even if no D-channel frame has to
be transmitted. It should be reset when the
access has been completed to grant a
similar access to other devices
transmitting in that IOM-channel.
Note: If the TIC-bus address (TBA2-0) is
programmed to ’7’ and is not
blocked by another device the
C165H writes its C/I0 code to IOM
continuously.
CICW 4 W 1 C/I-Channel Width
CICW selects between a 4 bit (’0’) and 6
bit (’1’) C/I1 channel width
CI1E 5 W 0 C/I-channel 1 interrupt enable
Interrupt generation ISTA.CIC of
CIR0.CIC1 is enabled (1) or masked (0).
Disabling the interrupt disables the CIC1
status indication.
TIC_DIS 6 R/W 0 TIC Bus Disable
0: The last octet of IOM channel 2 (11th
time slot) is used as TIC bus (TE
mode only).
1: The TIC bus is disabled. The last octet
of the last IOM time slot (11th time slot)
can be used as every time slot.
DIM 10:8 R/W 4 Digital Interface Modes
These bits define the characteristics of the
IOM Data Ports (DU, DD). The DIM0 bit
enables/disables the collission detection.
The DIM1 bit enables/disables the TIC
bus access. The effect of the individual
DIM bits is summarized in Table 70.
Reserved 15:7 R These bits are reserved
Field Bits Type Value Description
C165H
IOM-2 Interface Controller
Data Sheet 370 2001-04-19
PRELIMINARY
- EXCERPT -
Command/Indication Channel Status Register
Table 70 DIM Bit Setting
DIM2 DIM1 DIM0 Characteristics
0x0
Transparent D-channel, the collission detection is disabled
0x1
Stop/go bit evaluated for D-channel access handling
00x
Last octet of IOM channel 2 used for TIC bus access
01x
TIC bus access is disabled
1xx
Reserved
Address: 66H
Name: CIC_ST
151413121110 9 8 7 65432 1 0
CIC0 CIC1 S/G BAS RESERVED DCOD RESERVED
Field Bits Type Value Description
DCOD 7 R 0 DCL Clock Off Detection
Indicates the value of the DCL clock
detection counter:
0: Value of the DCL clock detection
counter is greater than ZERO
1: Value of the DCL clock detection
counter is ZERO
BAS 12 R 1 Bus Access Status
Indicates the state of the TIC-bus:
0: The C165H itself occupies the D-
channel
1: Another device or no device occupies
the D-channel
S/G 13 R 1 Stop/Go Bit Monitoring
Indicates the availability of the D-channel
on the line interface.
0: Go
1: Stop
C165H
IOM-2 Interface Controller
Data Sheet 371 2001-04-19
PRELIMINARY
- EXCERPT -
DCL Clock Supervision Interval
CIC1 14 R 0 C/I Code 1 Change
A change in the received Command/
Indication code in IOM-channel 1 has
been recognized. This bit is set when a
new code is detected in one IOM-frame. It
is reset by a read of CIR0.
CIC0 15 R 0 C/I Code 0 Change
A change in the received Command/
Indication code has been recognized. This
bit is set only when a new code is detected
in two consecutive IOM-frames. It is reset
by a read of CIR0.
Reserved 11:8,
6:0
R These bits are reserved
Address: 68H
Name: DCSI
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RESERVED DCSI_VAL
Field Bits Type Value Description
DCSI_VAL 10:0 R/W 00 DCL Clock Supervision Interval Value
Contains the initial value for the DCL clock
supervision 11-bit counter (see chapter
supervision).
RESERVED 15:11 R 00 These bits are reserved
Field Bits Type Value Description
C165H
IOM-2 Interface Controller
Data Sheet 372 2001-04-19
PRELIMINARY
- EXCERPT -
14.8.4 HDLC-Channel Registers
The register set for the HDLC-Channels is identical for each of the 4 channels.
Therefore, the HDLC-Channel registers are described only once. The start address for
each HDLC-Channel is given below:
The detailed HDLC-Channel register description, given in this chapter, contains the
relative address only.
Receive FIFO
HDLC-Channel Start Address (s_adr_x)
HD0 80
HD1 A0
HD2 C0
HD3 E0
Address: s_adr_x + 00H
Name: RFIFO_x
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
DATA
Field Bits Type Value Description
Data 15:0 R 0000HProvides word read access to the next
valid data.
After an ISTAH.RPF interrupt, a complete
data word is available.
After an ISTAH.RME interrupt, the number
of received bytes can be obtained by
reading the RBCL register.
C165H
IOM-2 Interface Controller
Data Sheet 373 2001-04-19
PRELIMINARY
- EXCERPT -
Transmit FIFO
Interrupt Status Register
Address: s_adr_x + 02H
Name: TFIFO_x
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
DATA
Field Bits Type Value Description
Data 15:0 W 0000HA write access provides data to the
TFIFO. Up to ten bytes of transmit data
can be written to the TFIFO following an
ISTAH.XPR interrupt.
Data can be written either word wide or
byte wide (with the valid byte at Low
position)
Address: s_adr_x + 04H
Name: ISTAH_x
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RME RPF RFO FFO RESERVED XPR XMR XDU XDOV RESERVED
Field Bits Type Value Description
RME 15 R 0 Receive Message End
The end of a frame has been received.
The message length and additional
information may be obtained from RBCH,
RBCL and the STAR register.
RPF 14 R 0 Receive Pool Full
A data word/byte has been received and is
available in the RFIFO.
C165H
IOM-2 Interface Controller
Data Sheet 374 2001-04-19
PRELIMINARY
- EXCERPT -
RFO 13 R 0 Receive Frame Overflow
The received data of a frame could not be
stored, because the RFIFO is occupied.
The whole message is lost and the FIFO is
flushed.
This interrupt can be used for statistical
purposes and indicates that the
microcontroller does not respond quickly
enough to an RPF or RME interrupt
(ISTAH).
FFO 12 R 0 Following Frame Overflow
This interrupt occurs if a new frame is
received while the previous frame still
occupies the FIFO. The new frame will be
rejected.
XPR 7 R 0 Transmit Pool Ready
A data word/byte can be written to the
TFIFO. An XPR interrupt will be generated
if the transmit FIFO can accept data and if
the XME flag is not set.
XMR 6 R 0 Transmit Message Repeat
The transmission of the last frame has to
be repeated because a collision has been
detected.
XDU 5 R 0 Transmit Data Underrun
The current transmission of a frame is
aborted by transmitting seven ’1’s
because the TFIFO holds no further data.
This interrupt occurs whenever the CPU
has failed to respond to an XPR interrupt
(ISTAH register) quickly enough, after
having initiated a transmission and the
message to be transmitted is not yet
complete.
XDOV 4 R 0 Transmit Data Overflow
Data has been written to the FIFO
although the FIFO is full, e.g. data has
been lost.
Field Bits Type Value Description
C165H
IOM-2 Interface Controller
Data Sheet 375 2001-04-19
PRELIMINARY
- EXCERPT -
Interrupt Mask Register
Each interrupt source in the ISTAH register can be selectively masked by setting to ’1’
the corresponding bit in MASKH. Masked interrupt status are still indicated when ISTAH
is read. All mask bits are set after reset (reset value FFFFH).
Status Register
RESERVED 11:8,
3:0
R These bits are reserved
Address: s_adr_x + 06H
Name: MASKH_x
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RME RPF RFO FFO RESERVED XPR XMR XDU XDOV RESERVED
Address: s_adr_x + 08H
Name: STAR_x
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
VFR RDO CRC RAB SA1 SA0 C/R TA RACI RESERVED XACI
Field Bits Type Value Description
RACI 7 R 0 Receiver Active Indication
The HDLC receiver is active when RACI =
’1’. This bit may be polled. The RACI bit is
set active after a begin flag has been
received and is reset after receiving an
abort sequence.
Field Bits Type Value Description
C165H
IOM-2 Interface Controller
Data Sheet 376 2001-04-19
PRELIMINARY
- EXCERPT -
VFR 15 R 0 Valid Frame
Determines whether a valid frame has
been received. The frame is valid (1) or
invalid (0). A frame is invalid when there is
not a multiple of 8 bits between flag and
frame end (flag, abort).
RDO 14 R 0 Receive Data Overflow
If RDO=1, at least one byte of the frame
has been lost, because it could not be
stored in RFIFO.
XACI 0 R 0 Transmitter Active Indication
The HDLC-transmitter is active when
XACI = ’1’. This bit may be polled. The
XACI-bit is active when an XTF-command
is issued and the frame has not been
completely transmitted.
CRC 13 R 0 CRC Check
The CRC is correct (1) or incorrect (0).
RAB 12 R 0 Receive Message Aborted
The receive message was aborted by the
remote station (1), i.e. a sequence of
seven 1’s was detected before a closing
flag.
SA1
SA0
TA
11
10
8
R
R
R
1
1
0
SAPI Address Identification
TEI Address Identification
SA1-0 are significant in non-auto-mode
with a two-byte address field, as well as in
transparent mode 3. TA is significant in all
modes except in transparent modes 0 and
1. Two programmable SAPI values
(SAP1, SAP2) plus a fixed group SAPI
(SAPG of value FC/FEH), and two
programmable TEI values (TEI1, TEI2)
plus a fixed group TEI (TEIG of value FFH),
are available for address comparison.
The result of the address comparison is
given by SA1-0 and TA, shown in table 71.
Field Bits Type Value Description
C165H
IOM-2 Interface Controller
Data Sheet 377 2001-04-19
PRELIMINARY
- EXCERPT -
C/R 9 R 0 Command/Response
The C/R bit contains the C/R bit of the
received frame (Bit1 in the SAPI address)
Note: The contents of STAR corresponds
to the last received HDLC frame; it
is duplicated into RFIFO for every
frame (last byte of frame)
Note: If SAP1 and SAP2 contains
identical values, the combination
001 will be omitted.
RESERVED 6:1 R These bits are reserved
Table 71 The result of the address comparison, given by SA1-0 and TA
Address Match with
SA1 SA0 TA 1st Byte 2nd Byte
Number of
Address
Bytes = 1
x
x
x
x
0
1
TEI2
TEI1
-
-
Number of
address
Bytes = 2
0
0
0
0
1
1
1
0
0
1
1
0
0
1
0
1
0
1
0
1
x
SAP2
SAP2
SAPG
SAPG
SAP1
SAP1
TEIG
TEI2
TEIG
TEI1 or TEI2
TEIG
TEI1
Field Bits Type Value Description
reserved
C165H
IOM-2 Interface Controller
Data Sheet 378 2001-04-19
PRELIMINARY
- EXCERPT -
Command Register
Address: s_adr_x + 0AH
Name: CMDR_x
15 141312111098 7 6 5 43210
RRES RESERVED XRES XME XTF RESERVED
Field Bits Type Value Description
RRES 15 W 0 Receiver Reset
HDLC receiver is reset, the RFIFO is
cleared of any data.
XRES 7 W 0 Transmitter Reset
HDLC transmitter is reset and the TFIFO
is cleared of any data. This command can
be used by the microcontroller to abort a
frame currently in transmission.
XME 6 W 0 Transmit Message End
By setting this bit to ’1’ the microcontroller
indicates that the data word written last in
the TFIFO completes the corresponding
frame. Except in the extended transparent
mode the transmission is terminated by
appending the CRC and the closing flag
sequence to the data.
XTF 5 W 0 Transmit Transparent Frame
The microcontroller initiates the
transmission of a transparent frame by
setting this bit to ’1’. Except in the
extended transparent mode the opening
flag is automatically added to the
message.
RESERVED 15 W These bits are reserved.
C165H
IOM-2 Interface Controller
Data Sheet 379 2001-04-19
PRELIMINARY
- EXCERPT -
IOM-2 Channel Selection
Note: The HDLC controller can transmit his data over any combination of the two 8-bit
IOM-2 channels and the two 2-bit IOM-2 channels.
Note: The HDLC controller are priroritized with controller HDLC0 having the highest and
HDLC3 the lowest priority. The IOM-2 channel enabling (B1, B2, D1, D2) is
exclusive, i.e. the controller with the higher priority will get the channel acces. The
enabling flag of the controller with the lower priority will be reset.
Address: s_adr_x + 0CH
Name: IOMSEL_x
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RESERVED EN_D2 EN_D1 EN_B2 EN_B1
Field Bits Type Value Description
EN_D2 3 R/W 0 Select second 2-bit IOM-2 Channel (D2)
Enable D2-Channel (2-bit) for HDLC-
controller access
EN_D1 2 R/W 0 Select first 2-bit IOM-2 Channel (D1)
Enable D1-Channel (2-bit) for HDLC-
controller access
EN_B2 1 R/W 0 Select second 8-bit IOM-2 Channel (B2)
Enable B2-Channel (8-bit) for HDLC-
controller access
EN_B1 0 R/W 0 Select first 8-bit IOM-2 Channel (B1)
Enable B1-Channel (8-bit) for HDLC-
controller access
RESERVED 15:7,
2:0
R These bits are reserved
C165H
IOM-2 Interface Controller
Data Sheet 380 2001-04-19
PRELIMINARY
- EXCERPT -
Mode Register
Address: s_adr_x + 0EH
Name: MODEH_x
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RPE XPE RES* SRA X
CRC
R
CRC RES* ITF MDS RES* RAC RES* =
RESERVED
Field Bits Type Value Description
MDS 7:5 R/W 0 Mode Select
Determines the message transfer mode of
the HDLC controller, as shown in Table
72.
RAC 3 R/W 0 Receiver Active
The HDLC receiver is activated when this
bit is set to ’1’. If it is ’0’ the HDLC data is
not evaluated in the receiver.
ITF 8 R/W 0 Interframe Time Fill
Selects the inter-frame time fill signal
which is transmitted between HDLC-
frames.
0: Idle (continuous ’1’)
1: Flags (sequence of patterns: ‘0111
1110’)
Note: ITF must be set to ’0’ for power
down mode.
In applications with D-channel
access handling (collision
resolution), the only possible inter-
frame time fill is idle (continuous
’1’). Otherwise the D-channel on
the line interface can not be
accessed
RCRC 10 R/W 0 Receive CRC
0: CRC is not stored in the RFIFO (i.e.
removed from incoming stream)
1: CRC is stored in the RFIFO
C165H
IOM-2 Interface Controller
Data Sheet 381 2001-04-19
PRELIMINARY
- EXCERPT -
XCRC 11 R/W 0 Transmit CRC
0: CRC is transmitted (i.e. generated)
1: CRC is not transmitted
SRA 12 R/W 0 Store Receive Address
0: Receive Address is not stored in the
RFIFO
1: Receive Address is stored in the
RFIFO
XPE 14 R/W 0 Transmit PEC Enable
Enables the XPR interrupt for HDLC
channel
0: XPR interrupt disabled
1: XPR interrupt enabled
RPE 15 R/W 0 Receive PEC Enable
Enables the RPF interrupt for HDLC
channel
0: RPF interrupt disabled
1: RPF interrupt enabled
RES* = RESERVED 13,9,
4, 2:0
R These bits are reserved.
Table 72 Message transfer: Mode Select
MDS2-0 Mode Number of
Address
Bytes
Address Comparison Remark
1.Byte 2.Byte
0 0 0 Reserved
0 0 1 Reserved
0 1 0 Non-Auto
mode
1TEI1,TEI2–One-byte address
compare.
0 1 1 Non-Auto
mode
2 SAP1,SAP2,SAPG TEI1,TEI2,TEIG Two-byte address
compare.
1 0 0 Extended
transparent
mode
1 1 0 Transparent
mode 0
–– – No address
compare. All
frames accepted.
Field Bits Type Value Description
C165H
IOM-2 Interface Controller
Data Sheet 382 2001-04-19
PRELIMINARY
- EXCERPT -
Note: SAP1, SAP2: two programmable address values for the first received address
byte (in the case of an address field longer than 1 byte);
SAPG = fixed value FC / FEH.
TEI1, TEI2: two programmable address values for the second (or the only, in the
case of a one-byte address) received address byte; TEIG = fixed value FFH
Two different methods of the high byte and/or low byte address comparision can
be selected by setting SAP1.MHA and/or SAP2.ML
SAPI1 Register
1 1 1 Transparent
mode 1
> 1 SAP1,SAP2,SAPG –High-byte address
compare.
1 0 1 Transparent
mode 2
> 1 –TEI1,TEI2,TEIG Low-byte address
compare.
Address: s_adr_x + 10H
Name: SAP1_x
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RESERVED SAPI1
RES
ERV
ED
MHA
Field Bits Type Value Description
SAPI1 7:2 W 3FHSAPI1 value
Value of the first programmable Service
Access Point Identifier (SAPI) according
to the ISDN LAPD protocol.
Table 72 Message transfer: Mode Select (cont’d)
MDS2-0 Mode Number of
Address
Bytes
Address Comparison Remark
1.Byte 2.Byte
C165H
IOM-2 Interface Controller
Data Sheet 383 2001-04-19
PRELIMINARY
- EXCERPT -
SAPI2 Register
MHA 0 W 0 Mask High Address
0: The SAPI address of an incomming
frame is compared with SAP1, SAP2,
SAPG
1: The SAPI address of an incomming
frame is compared with SAP1 and
SAPG.
SAP1 can be masked with SAP2 thereby
bitpositions of SAP1 are not compared
if they are set to ’1’ in SAP2.
RESERVED 14:13
9,4
R These bits are reserved.
Address: s_adr_x + 12H
Name: SAP2_x
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RESERVED SAPI2
RES
ERV
ED
MLA
Field Bits Type Value Description
SAPI2 7:2 W 3FHSAPI2 value
Value of the second programmable
Service Access Point Identifier (SAPI)
according to the ISDN LAPD-protocol.
Field Bits Type Value Description
C165H
IOM-2 Interface Controller
Data Sheet 384 2001-04-19
PRELIMINARY
- EXCERPT -
Receive Frame Byte Count
MLA 0 W 0 Mask Low Address
0: The TEI address of an incomming
frame is compared with TEI1, TEI2,
TEIG
1: The TEI address of an incomming
frame is compared with TEI1
andTEIG.
TEI1 can be masked with TEI2 thereby
bitpositions of TEI1 are not compared
if they are set to ’1’ in TEI2
RESERVED 14:13
9,4
R These bits are reserved.
Address: s_adr_x + 14H
Name: RBC_x
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RESERVED OV RBC
Field Bits Type Value Description
C165H
IOM-2 Interface Controller
Data Sheet 385 2001-04-19
PRELIMINARY
- EXCERPT -
Field Bits Type Value Description
RBC 11:0 R/W 000H12 bits of the total number of bytes in a
received message. Bit 11 is the most
significant bit, bit 0 the least significant bit,
respective.
Note: Normally RBC should be read by
the microcontroller after an RME-
interrupt in order to determine the
number of bytes to be read from the
RFIFO, and the total message
length. The contents of the registers
are valid only after an RME or RPF
interrupt, and remain so until the
frame is acknowledged via
resetting RBC (I.e. writing a value to
RBC) or via resetting the RFIFO
(i.e. setting RRES).
OV 12 R/W 0 Overflow
A ’1’ in this bit position indicates a
message longer than (212 - 1) = 4095
bytes .
RESERVED 15:13 R These bits are reserved.
C165H
IOM-2 Interface Controller
Data Sheet 386 2001-04-19
PRELIMINARY
- EXCERPT -
TEI1 Register
Address: s_adr_x + 16H
Name: TEI1_x
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RESERVED TEI1 EA
Field Bits Type Value Description
TEI1 7:1 W 7FHTerminal Endpoint Identifier
In all message transfer modes except in
transparent modes 0, 1 and extended
transparent mode, TEI1 is used for
address recognition. In the case of a two-
byte address field, it contains the value of
the first programmable Terminal Endpoint
Identifier according to the ISDN LAPD-
protocol.
In non-auto-modes with one-byte address
field, TEI1 is a command address,
according to X.25 LAPB.
EA 0 W 1 Address field Extension bit
This bit is set to ’1’ according to HDLC/
LAPD.
RESERVED 15:8 R These bits are reserved.
C165H
IOM-2 Interface Controller
Data Sheet 387 2001-04-19
PRELIMINARY
- EXCERPT -
TEI2 Register
Address: s_adr_x + 18H
Name: TEI2_x
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RESERVED TEI1 EA
Field Bits Type Value Description
TEI1 7:1 W 7FHTerminal Endpoint Identifier
In all message transfer modes except in
transparent modes 0, 1 and extended
transparent mode, TEI2 is used for
address recognition. In the case of a two-
byte address field, it contains the value of
the second programmable Terminal
Endpoint Identifier according of the ISDN
LAPD-protocol.
In non-auto-modes with one-byte address
field, TEI2 is a response address,
according to X.25 LAPD.
EA 0 W 1 Address field Extension bit
This bit is to be set to ’1’ according to
HDLC/LAPD.
RESERVED 15:8 R These bits are reserved.
C165H
IOM-2 Interface Controller
Data Sheet 388 2001-04-19
PRELIMINARY
- EXCERPT -
Looping Register
Address: s_adr_x + 1AH
Name: LOOP_x
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RESERVED ELP FAST TLP
Field Bits Type Value Description
TLP 0 R/W 0 Transmit Loop
Setting TLP to ’1’ causes outgoing data
being looped back into the receiver. The
received data contains all HDLC
procession, but does not contain the start
and ending Flag.
FAST 1 R/W 0 Fast Looping
Setting FAST = ’1’ affects the TLP timing.
’0’: The TLP is processed with the IOM-2
lines condition (8 kHz signal).
’1’: The TLP looping runs with the BCL
clock.
ELP 2 R/W 0 External Loop
Setting ELP to ’1’ causes incomming
HDLC data being looped back to the line.
C165H
Watchdog Timer (WDT)
Data Sheet 389 2001-04-19
PRELIMINARY
- EXCERPT -
15 Watchdog Timer (WDT)
To allow recovery from software or hardware failure, the C165H provides a Watchdog
Timer. If the software fails to service this timer before an overflow occurs, an internal
reset sequence will be initiated. This internal reset will also pull the RSTOUT pin low,
which also resets the peripheral hardware, which might be the cause for the malfunction.
When the watchdog timer is enabled and the software has been designed to service it
regularly before it overflows, the watchdog timer will supervise the program execution,
as it only will overflow if the program does not progress properly. The watchdog timer will
also time out, if a software error was due to hardware related failures. This prevents the
controller from malfunctioning for longer than a user-specified time.
The watchdog timer provides two registers: a read-only timer register that contains the
current count, and a control register for initialization.
Figure 125 SFRs and Port Pins associated with the Watchdog Timer
The watchdog timer is a 16-bit up counter which can be clocked with the CPU clock (fCPU)
either divided by 2 or divided by 128. This 16-bit timer is realized as two concatenated
8-bit timers (see figure below). The upper 8 bits of the watchdog timer can be preset to
a user-programmable value via a watchdog service access in order to vary the watchdog
expire time. The lower 8 bits are reset on each service access.
Figure 126 Watchdog Timer Block Diagram
WDT WDTCON
RSTOUT
Reset Indication Pin Data Registers Control Registers
MCB02052
WDT High Byte WDTR
MUX
÷ 2
RSTOUT
WDTIN
WDT Low Byte
WDTRELControl
WDT
÷ 128
f
CPU
Reset
Clear
C165H
Watchdog Timer (WDT)
Data Sheet 390 2001-04-19
PRELIMINARY
- EXCERPT -
15.1 Operation of the Watchdog Timer
The current count value of the Watchdog Timer is contained in the Watchdog Timer
Register WDT, which is a non-bitaddressable read-only register. The operation of the
Watchdog Timer is controlled by its bitaddressable Watchdog Timer Control Register
WDTCON. This register specifies the reload value for the high byte of the timer, selects
the input clock prescaling factor and provides a flag that indicates a watchdog timer
overflow.
WDTCON (FFAEH / D7H) SFR Reset Value: 00XXH
The reset sources supported by the C165H are summarized in Table 73.
Note: Differentiation between long and short hardware reset, known from other Infineon
C16x devices, is not supported.
Note: An internal power-on detection circuitry, also known from other C16x devices, is
not implemented. Therefore, bit WDTCON.5 (in other devices called PONR -
power-on reset) is reserved.
Bit Function
WDTIN Watchdog Timer Input Frequency
Selection
‘0’: Input frequency is fCPU / 2
‘1’: Input frequency is fCPU / 128
WDTR Watchdog Timer Reset Indication Flag
Set by the watchdog timer on an overflow.
Cleared by the SRVWDT instruction.
SWR Software Reset
Set by the command SRST
SHWR Short Hardware Reset
Set by the input RSTIN Note: The C165H does not
distinguish between short and
long hardware reset.
LHWR Long Hardware Reset
Set by the input RSTIN
reserved Reserved
These bits are reserved
WDTREL Watchdog Timer Reload Value (for the high
byte)
SHW
RWDT
R
SWR WDT
IN
LHW
R
54321011 10 987615 14 13 12
rrw - -
WDTREL
rw
rr r
-
RESERVED
C165H
Watchdog Timer (WDT)
Data Sheet 391 2001-04-19
PRELIMINARY
- EXCERPT -
Note: The WDTCON register bits [7, 6, 5] 4, 3, 2 and 1 are cleared by the EINIT
command.
After any software reset, external hardware reset, or watchdog timer reset, the watchdog
timer is enabled and starts counting up from 0000H with the frequency fCPU/2. The input
frequency may be switched to fCPU/128 by setting bit WDTIN. The watchdog timer can
be disabled via the instruction DISWDT (Disable Watchdog Timer). Instruction DISWDT
is a protected 32-bit instruction which will ONLY be executed during the time between a
reset and execution of either the EINIT (End of Initialization) or the SRVWDT (Service
Watchdog Timer) instruction. Either one of these instructions disables the execution of
DISWDT.
When the watchdog timer is not disabled via instruction DISWDT, it will continue
counting up, even during Idle Mode. If it is not serviced via the instruction SRVWDT by
the time the count reaches FFFFH the watchdog timer will overflow and cause an internal
reset. This reset will pull the external reset indication pin RSTOUT low. It differs from a
software or external hardware reset in that bit WDTR (Watchdog Timer Reset Indication
Flag) of register WDTCON will be set. A hardware reset or the SRVWDT instruction will
clear this bit. Bit WDTR can be examined by software in order to determine the cause of
the reset.
A watchdog reset will also complete a running external bus cycle before starting the
internal reset sequence if this bus cycle does not use READY or samples READY active
(low) after the programmed waitstates. Otherwise the external bus cycle will be aborted.
Note: After a hardware reset that activates the Bootstrap Loader the watchdog timer will
be disabled.
To prevent the watchdog timer from overflowing, it must be serviced periodically by the
user software. The watchdog timer is serviced with the instruction SRVWDT, which is a
protected 32-bit instruction. Servicing the watchdog timer clears the low byte and reloads
the high byte of the watchdog timer register WDT with the preset value from bitfield
WDTREL which is the high byte of register WDTCON. Servicing the watchdog timer will
also reset bit WDTR. After being serviced the watchdog timer continues counting up from
the value (<WDTREL> * 28). Instruction SRVWDT has been encoded in such a way that
the chance of unintentionally servicing the watchdog timer (eg. by fetching and executing
a bit pattern from a wrong location) is minimized. When instruction SRVWDT does not
Table 73 WDTCON Register: Reset Source Identification
Type of Reset WDTCON
Reset Value
WDTCON Flags being set
Hardware reset via pin RSTIN 001CHLHWR, SHWR, SWR
Software reset via command SRST 0004HSWR
Watchdog Timer reset 0006HSWR, WDTR
C165H
Watchdog Timer (WDT)
Data Sheet 392 2001-04-19
PRELIMINARY
- EXCERPT -
match the format for protected instructions the Protection Fault Trap will be entered,
rather than the instruction be executed.
The time period for an overflow of the watchdog timer is programmable in two ways:
• the input frequency to the watchdog timer can be selected via bit WDTIN in register
WDTCON to be either fCPU/2 or fCPU/128.
• the reload value WDTREL for the high byte of WDT can be programmed in register
WDTCON.
The period PWDT between servicing the watchdog timer and the next overflow can
therefore be determined by the following formula:
Note: For safety reasons, the user is advised to rewrite WDTCON each time before the
watchdog timer is serviced.
PWDT = fCPU
2(1 + <WDTIN>*6) * (216 - <WDTREL> * 28)
C165H
Bootstrap Loader
Data Sheet 393 2001-04-19
PRELIMINARY
- EXCERPT -
16 Bootstrap Loader
The built-in bootstrap loader of the C165H provides a mechanism to load the startup
program, which is executed after reset, via the serial interface.
The bootstrap loader moves code/data into the internal RAM, but it is also possible to
transfer data via the serial interface into an external RAM using a second level loader
routine. It may be used to provide lookup tables or may provide “core-code”, ie. a set of
general purpose subroutines, eg. for I/O operations, number crunching, system
initialization, etc.
Figure 127 Bootstrap Loader Sequence
The Bootstrap Loader may be used to load the complete application software into
ROMless systems, it may load temporary software into complete systems for testing or
calibration.
The BSL mechanism may be used for standard system startup as well as only for special
occasions like system maintenance (firmware update) or end-of-line programming or
testing.
RSTIN
TxD0
Int. Boot ROM BSL-routine 32 bytes
2)
3)
RxD0
CSP:IP
user software
4)
6)
P0L.4
1) BSL initialization time, > 2µs @ fCPU = 20 MHz.
2) Zero byte (1 start bit, eight ‘0’ data bits, 1 stop bit), sent by host.
3) Identification byte, sent by C165H.
4) 32 bytes of code / data, sent by host.
1)
5)
C165H
Bootstrap Loader
Data Sheet 394 2001-04-19
PRELIMINARY
- EXCERPT -
Entering the Bootstrap Loader
The C165H enters BSL mode if pin P0L.4 is sampled low at the end of a hardware reset.
In this case the built-in bootstrap loader is activated independent of the selected bus
mode.
After entering BSL mode and the respective initialization the C165H scans the RXD0 line
to receive a zero byte, ie. one start bit, eight ‘0’ data bits and one stop bit. From the
duration of this zero byte it calculates the corresponding baudrate factor with respect to
the current CPU clock, initializes the serial interface ASC accordingly and switches pin
TxD0 to output. Using this baudrate, an identification byte is returned to the host that
provides the loaded data.
This identification byte identifies the device to be booted. The following codes are
defined for Infineon Technologies microcontrollers:
55H: 8xC166.
A5H: Previous versions of the C167 (obsolete).
B5H: C165.
C5H: C167 derivatives.
D5H: C165H (and all other devices equipped with identification registers).
Note: The identification byte D5H does not directly identify a specific derivative. This
information can in this case be obtained from the identification registers.
When the C165H has entered BSL mode, the following configuration is automatically set
(values that deviate from the normal reset values, are marked):
Watchdog Timer: Disabled Register SYSCON: 0E00H
Context Pointer CP: FA00H Register STKUN: FA40H
Stack Pointer SP: FA40H Register STKOV: FA0CH 0<->C
Register S0CON: 8011H Register BUSCON0: acc. to startup config.
Register S0BG: acc. to ‘00’ byte P3.10 / TXD0: ‘1’
DP3.10: ‘1’
Other than after a normal reset the watchdog timer is disabled, so the bootstrap loading
sequence is not time limited. Pin TXD0 is configured as output, so the C165H can return
the identification byte.
The hardware that activates the BSL during reset may be a simple pull-down resistor on
P0L.4 for systems that use this feature upon every hardware reset. You may want to use
a switchable solution (via jumper or an external signal) for systems that only temporarily
use the bootstrap loader.
C165H
Bootstrap Loader
Data Sheet 395 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 128 Hardware Provisions to Activate the BSL
After sending the identification byte the ASC receiver is enabled and is ready to receive
the initial 32 bytes from the host. A half duplex connection is therefore sufficient to feed
the BSL.
Note: In order to properly enter BSL mode it is not only required to pull P0L.4 low,
but also pins P0L.2, P0L.3, P0L.5 must receive defined levels.
This is described in chapter "System Reset“.
Loading the Startup Code
After sending the identification byte the BSL enters a loop to receive 32 bytes via ASC.
These bytes are stored sequentially into locations 00’FA40H through 00’FA5FH of the
internal RAM. So up to 16 instructions may be placed into the RAM area. To execute the
loaded code the BSL then jumps to location 00’FA40H, ie. the first loaded instruction. The
bootstrap loading sequence is now terminated, the C165H remains in BSL mode,
however. Most probably the initially loaded routine will load additional code or data, as
an average application is likely to require substantially more than 16 instructions. This
second receive loop may directly use the pre-initialized interface ASC to receive data
and store it to arbitrary user-defined locations.
This second level of loaded code may be the final application code. It may also be
another, more sophisticated, loader routine that adds a transmission protocol to enhance
the integrity of the loaded code or data. It may also contain a code sequence to change
the system configuration and enable the bus interface to store the received data into
external memory.
This process may go through several iterations or may directly execute the final
application. In all cases the C165H will still run in BSL mode, ie. with the watchdog timer
disabled and limited access to the internal code memory.
MCA02261
P0L.4
Ω
Circuit_1
P0L.4
R
8 k
P0L.4
External Signal
R
BSL
8 k
P0L.4
Ω
Normal Boot
Circuit_2
C165H
Bootstrap Loader
Data Sheet 396 2001-04-19
PRELIMINARY
- EXCERPT -
Exiting Bootstrap Loader Mode
In order to execute a program in normal mode, the BSL mode must be terminated first.
The C165H exits BSL mode upon a software reset (ignores the level on P0L.4) or a
hardware reset (P0L.4 must be high then!). After a reset the C165H will start executing
from location 00’0000H of the external memory (make sure, pin EA is tied to ’0’ signal).
Choosing the Baudrate for the BSL
The calculation of the serial baudrate for ASC from the length of the first zero byte that
is received, allows the operation of the bootstrap loader of the C165H with a wide range
of baudrates. However, the upper and lower limits have to be kept, in order to insure
proper data transfer.
The C165H uses timer T6 to measure the length of the initial zero byte. The quantization
uncertainty of this measurement implies the first deviation from the real baudrate, the
next deviation is implied by the computation of the S0BRL reload value from the timer
contents. The formula below shows the association:
For a correct data transfer from the host to the C165H the maximum deviation between
the internal initialized baudrate for ASC and the real baudrate of the host should be
below 2.5%. The deviation (FB, in percent) between host baudrate and C165H baudrate
can be calculated via the formula below:
Note: Function (FB) does not consider the tolerances of oscillators and other devices
supporting the serial communication.
This baudrate deviation is a nonlinear function depending on the CPU clock and the
baudrate of the host. The maxima of the function (FB) increase with the host baudrate
due to the smaller baudrate prescaler factors and the implied higher quantization error
(see figure below).
fCPU
32 S0BRL 1
+()⋅
-------------------------------------------
BC165H
S0BRL T6 36–
72
-------------------
=T6 9
4
--
fCPU
BHost
---------------
⋅=
,
FB
BContr BHost
–
BContr
----------------------------------------100⋅=%FB2,5≤%
,
C165H
Bootstrap Loader
Data Sheet 397 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 129 Baudrate deviation between host and C165H
Minimum baudrate (BLow in the figure above) is determined by the maximum count
capacity of timer T6, when measuring the zero byte, ie. it depends on the CPU clock.
Using the maximum T6 count 216 in the formula the minimum baudrate for fCPU=20 MHz
is 687 Baud. The lowest standard baudrate in this case would be 1200 Baud. Baudrates
below BLow would cause T6 to overflow. In this case ASC cannot be initialized properly.
Maximum baudrate (BHigh in the figure above) is the highest baudrate where the
deviation still does not exceed the limit, ie. all baudrates between BLow and BHigh are
below the deviation limit. The maximum standard baudrate that fulfills this requirement
is 19200 Baud.
Higher baudrates, however, may be used as long as the actual deviation does not
exceed the limit. A certain baudrate (marked I) in the figure) may eg. violate the deviation
limit, while an even higher baudrate (marked II) in the figure) stays very well below it. This
depends on the host interface.
MCA02260
B
F
2.5%
Low
B B
High
Ι
ΙΙ
B
Host
C165H
System Reset
Data Sheet 398 2001-04-19
PRELIMINARY
- EXCERPT -
17 System Reset
The internal system reset function provides initialization of the C165H into a defined
default state and is invoked either by asserting a hardware reset signal on pin RSTIN
(Hardware Reset Input), upon the execution of the SRST instruction (Software Reset) or
by an overflow of the watchdog timer (WDT).
Whenever one of these conditions occurs, the microcontroller is reset into its predefined
default state through an internal reset procedure. When a reset is initiated, pending
internal hold states are cancelled and the current internal access cycle (if any) is
completed. An external bus cycle is aborted, except for a watchdog reset (see
description). After that the bus pin drivers and the I/O pin drivers are switched off
(tristate). RSTOUT is activated depending on the reset source.
The internal reset procedure requires 516 CPU clock cycles in order to perform a
complete reset sequence. This 516 cycle reset sequence is started upon a watchdog
timer overflow, a SRST instruction or when the reset input signal RSTIN is latched low
(hardware reset). The internal reset condition is active at least for the duration of the
reset sequence and then until the RSTIN input is inactive. When this internal reset
condition is removed (reset sequence complete and RSTIN inactive), the reset
configuration is latched from PORT0, and pins ALE, RD and WR are driven to their
inactive levels.
Note: Bit ADP, which selects the Adapt mode during low RSTIN signal, is latched with
the rising edge of RSTIN.
After the internal reset condition is removed, the microcontroller will start program
execution from memory location 00’0000H in code segment zero. This start location will
typically hold a branch instruction to the start of a software initialization routine for the
application specific configuration of peripherals and CPU Special Function Registers.
C165H
System Reset
Data Sheet 399 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 130 External Reset Circuitry
Hardware Reset
A hardware reset is triggered when the reset input signal RSTIN is latched low. To
ensure the recognition of the RSTIN signal (latching), it must be held low for at least
8 CPU clock cycles.
Note: During reset, the CPU is clocked with the free-running PLL clock which may run
as slow as < 1 MHz.
Also shorter RSTIN pulses may trigger a hardware reset, if they coincide with the latch’s
sample point. However, it is recommended to keep RSTIN low for ca. 1 ms. After the
reset sequence has been completed, the RSTIN input is sampled. When the reset input
signal is active at that time the internal reset condition is prolonged until RSTIN gets
inactive.
During a hardware reset the PORT0 inputs for the reset configuration need some time
to settle on the required levels, especially if the hardware reset aborts a read operation
form an external peripheral. During this settling time the configuration may intermittently
be wrong. In such a case also the PLL clock selection may be wrong.
Note: To ensure a glitch free start-up of the C165H, it is strongly recommended to
provide an external reset pulse of ca. 1 ms in order to allow the PLL to settle on
the desired CPU clock frequency.
The input RSTIN provides an internal pullup device equalling a resistor of 100 KΩ to
660 KΩ (the minimum reset time must be determined by the lowest value). Simply
connecting an external capacitor is sufficient for an automatic power-on reset, see b) in
Reset
+
a) Generated Warm Reset
b) Automatic Power-ON Reset
&
MCA04934
RSTOUT
C165H
External
Hardware
a)
b)
External
Reset
Sources
CC
V
RSTIN
C165H
System Reset
Data Sheet 400 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 130. RSTIN may also be connected to the output of other logic gates, see a)
same figure.
Note: A power-on reset requires an active time of two reset sequences (1036 CPU clock
cycles) after a stable clock signal is available (about 10...50 ms to allow the on-
chip oscillator to stabilize).
Software Reset
The reset sequence can be triggered at any time via the protected instruction SRST
(Software Reset). This instruction can be executed deliberately within a program, eg. to
leave bootstrap loader mode, or upon a hardware trap that reveals a system failure.
C165H’s latched in reset configuration on software reset is shown in Figure 132,
page 406.
Watchdog Timer Reset
When the watchdog timer is not disabled during the initialization or serviced regularly
during program execution it will overflow and trigger the reset sequence. Other than
hardware and software reset the watchdog reset completes a running external bus cycle
if this bus cycle either does not use READY at all, or if READY is sampled active (low)
after the programmed waitstates. When READY is sampled inactive (high) after the
programmed waitstates the running external bus cycle is aborted. Then the internal reset
sequence is started.
Note: For latched in watchdog reset configuration, refer to Figure 132, page 406.
The watchdog reset cannot occur while the C165H is in bootstrap loader mode!
The C165H’s Pins after Reset
After the reset sequence the different groups of pins of the C165H are activated in
different ways depending on their function. Bus and control signals are activated
immediately after the reset sequence according to the configuration latched from
PORT0, so either external accesses can take place or the external control signals are
inactive. The general purpose I/O pins remain in input mode (high impedance) until
reprogrammed via software (see figure below). The RSTOUT pin remains active (low)
until the end of the initialization routine (see description).
C165H
System Reset
Data Sheet 401 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 131 Reset Input and Output Signals
Reset Output Pin
The RSTOUT pin is dedicated to generate a reset signal for the system components
besides the controller itself. RSTOUT will be driven active (low) at the begin of any reset
sequence (triggered by hardware, the SRST instruction or a watchdog timer overflow).
RSTOUT stays active (low) beyond the end of the internal reset sequence until the
protected EINIT (End of Initialization) instruction is executed (see figure above). This
delayed until the end of the internal reset condition.
Current bus cycle is completed or aborted.
Activation of the IO pins is controlled by software.
Execution of the EINIT instruction.
When the internal reset condition is extended by RSTIN, the activation of the output signals is
Switches asinchronously with RSTIN, sinchronously upon software or watchdog reset.
The reset condition ends here. The C 167CR starts program execution.
The shaded area designates the internal reset sequence, which starts after synchronization of RSTIN.
RSTIN
Internal Reset Condition
6)
Initialization
3)
MCS02258
RD, WR
RSTOUT
IO
ALE
Bus
RSTIN
Internal Reset Condition
6)
1)
2)
2)
Initialization
3) 5)
4)
8)
7)
A short hardware reset is extended until the end of the reset sequence in Bidirectional reset mode.
A software or WDT reset activates the RSTIN line in Bidirectional reset mode.
8)
7)
6)
3)
2)
5)
4)
1)
C165H
System Reset
Data Sheet 402 2001-04-19
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allows the complete configuration of the controller including its on-chip peripheral units
before releasing the reset signal for the external peripherals of the system.
Watchdog Timer Operation after Reset
The watchdog timer starts running after the internal reset has completed. It will be
clocked with the internal system clock divided by 2 (18 MHz @ fCPU=36 MHz), and its
default reload value is 00H, so a watchdog timer overflow will occur 131072 CPU clock
cycles (3.64 ms @ fCPU=36 MHz) after completion of the internal reset, unless it is
disabled, serviced or reprogrammed meanwhile. When the system reset was caused by
a watchdog timer overflow, the WDTR (Watchdog Timer Reset Indication) flag in register
WDTCON will be set to '1'. This indicates the cause of the internal reset to the software
initialization routine. WDTR is reset to '0' by an external hardware reset or by servicing
the watchdog timer. After the internal reset has completed, the operation of the watchdog
timer can be disabled by the DISWDT (Disable Watchdog Timer) instruction. This
instruction has been implemented as a protected instruction. For further security, its
execution is only enabled in the time period after a reset until either the SRVWDT
(Service Watchdog Timer) or the EINIT instruction has been executed. Thereafter the
DISWDT instruction will have no effect.
Note: For a complete description of register WDTCON, refer to Chapter 15.1, page 390.
Reset Values for the C165H Registers
During the reset sequence the registers of the C165H are preset with a default value.
Most SFRs, including system registers and peripheral control and data registers, are
cleared to zero, so all peripherals and the interrupt system are off or idle after reset. A
few exceptions to this rule provide a first pre-initialization, which is either fixed or
controlled by input pins.
DPP1: 0001H (points to data page 1)
DPP2: 0002H (points to data page 2)
DPP3: 0003H (points to data page 3)
CP: FC00H
STKUN: FC00H
STKOV: FA00H
SP: FC00H
WDTCON: 00XXH, (value depends on the reset configuration)
S0RBUF: XXH (undefined)
SSCRB: XXXXH (undefined)
SYSCON: 0XX0H (set according to reset configuration)
BUSCON0: 0XX0H (set according to reset configuration)
RP0H: XXH (reset levels of P0H)
ONES: FFFFH (fixed value)
C165H
System Reset
Data Sheet 403 2001-04-19
PRELIMINARY
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The Internal RAM after Reset
The contents of the internal RAM are not affected by a system reset. However, after
power-on the contents of the internal RAM are undefined. This implies that the GPRs
(R15...R0) and the PEC source and destination pointers (SRCP7...SRCP0,
DSTP7...DSTP0) which are mapped into the internal RAM are also unchanged after a
hardware reset, software reset or watchdog reset, but are undefined after power-on.
Ports and External Bus Configuration during Reset
During the internal reset sequence all of the C165H's port pins are configured as inputs
by clearing the associated direction registers, and their pin drivers are switched to the
high impedance state. This ensures that the C165H and external devices will not try to
drive the same pin to different levels. Pin ALE is held low through an internal pulldown,
and pins RD and WR are held high through internal pullups. Also the pins selected for
CS output will be pulled high.
The registers SYSCON and BUSCON0 are initialized according to the configuration
selected via PORT0:
• the Bus Type field (BTYP) in register BUSCON0 is initialized according to P0L.7 and
P0L.6
• bit BUSACT0 in register BUSCON0 is set to ‘1’
• bit ALECTL0 in register BUSCON0 is set to ‘1’
• bit ROMEN in register SYSCON will be cleared to ‘0’
• bit BYTDIS in register SYSCON is set according to the data bus width
Note: In the C165H, pin EA must always be set to ’0’. The "internal start" (EA=’1’), known
from other Infineon C16x devices is not supported.
The other bits of register BUSCON0, and the other BUSCON registers are cleared. This
default initialization selects the slowest possible external accesses using the configured
bus type. The Ready function is disabled at the end of the internal system reset.
When the internal reset has completed, the configuration of PORT0, PORT1, Port 4,
Port 6 and of the BHE signal (High Byte Enable, alternate function of P3.12) depends on
the bus type which was selected during reset. When any of the external bus modes was
selected during reset, PORT0 (and PORT1) will operate in the selected bus mode. Port 4
will output the selected number of segment address lines (all zero after reset) and Port 6
will drive the selected number of CS lines (CS0 will be ‘0’, while the other active CS lines
will be ‘1’). When no memory accesses above 64 K are to be performed, segmentation
may be disabled.
When the on-chip bootstrap loader was activated during reset, pin TxD0 (alternate
function of P3.10) will be switched to output mode after the reception of the zero byte.
All other pins remain in the high-impedance state until they are changed by software or
peripheral operation.
C165H
System Reset
Data Sheet 404 2001-04-19
PRELIMINARY
- EXCERPT -
Application-Specific Initialization Routine
After the internal reset condition is removed the C165H fetches the first instruction from
location 00’0000H, which is the first vector in the trap/interrupt vector table, the reset
vector. 4 words (locations 00’0000H through 00’0007H) are provided in this table to start
the initialization after reset. As a rule, this location holds a branch instruction to the actual
initialization routine that may be located anywhere in the address space.
Note: When the Bootstrap Loader Mode was activated during a hardware reset the
C165H does not fetch instructions from location 00’0000H but rather expects data
via serial interface ASC.
The first instruction is fetched from external memory. To decrease the number of
instructions required to initialize the C165H, each peripheral is programmed to a default
configuration upon reset, but is disabled from operation. These default configurations
can be found in the descriptions of the individual peripherals.
During the software design phase, portions of the internal memory space must be
assigned to register banks and system stack. When initializating the stack pointer (SP)
and the context pointer (CP), it must be ensured that these registers are initialized before
any GPR or stack operation is performed. This includes interrupt processing, which is
disabled upon completion of the internal reset, and should remain disabled until the SP
is initialized.
Note: Traps (incl. NMI) may occur, even though the interrupt system is still disabled.
In addition, the stack overflow (STKOV) and the stack underflow (STKUN) registers
should be initialized. After reset, the CP, SP, and STKUN registers all contain the same
reset value 00’FC00H, while the STKOV register contains 00’FA00H. With the default
reset initialization, 256 words of system stack are available, where the system stack
selected by the SP grows downwards from 00’FBFEH, while the register bank selected
by the CP grows upwards from 00’FC00H.
Based on the application, the user may wish to initialize portions of the internal memory
before normal program operation. Once the register bank has been selected by
programming the CP register, the desired portions of the internal memory can easily be
initialized via indirect addressing.
At the end of the initialization, the interrupt system may be globally enabled by setting bit
IEN in register PSW. Care must be taken not to enable the interrupt system before the
initialization is complete.
The software initialization routine should be terminated with the EINIT instruction. This
instruction has been implemented as a protected instruction. Execution of the EINIT
instruction...
• disables the action of the DISWDT instruction,
• disables write accesses to register SYSCON,
C165H
System Reset
Data Sheet 405 2001-04-19
PRELIMINARY
- EXCERPT -
Note: All configurations regarding register SYSCON (enable CLKOUT, stacksize,
etc.) must be selected before the execution of EINIT.
• disables write access to registers SYSCON2 and SYSCON3 (further write accesses
to SYSCON2 and SYSCON3 can be executed only using a special unlock
mechanism),
• clears the reset source detection bits in register WDTCON,
• causes the RSTOUT pin to go HIGH. This signal can be used to indicate the end of
the initialization routine and the proper operation of the microcontroller to external
hardware.
17.1 System Startup Configuration
Although most of the programmable features of the C165H are either selected during the
initialization phase or repeatedly during program execution, there are some features that
must be selected earlier, because they are used for the first access of the program
execution.
These selections are made during reset via the pins of PORT0, which are read at the
end of the internal reset sequence. During reset internal pullup devices are active on the
PORT0 lines, so their input level is high, if the respective pin is left open, or is low, if the
respective pin is connected to an external pulldown device. With the coding of the
selections, as shown below, in many cases the default option, ie. high level, can be used.
The value on the upper byte of PORT0 (P0H) is latched into register RP0H upon reset,
the value on the lower byte (P0L) directly influences the BUSCON0 register (bus mode)
or the internal control logic of the C165H.
C165H
System Reset
Data Sheet 406 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 132 PORT0 Configuration during Reset
Note: The configuration on pins P0H.7:P0H.5 (CLKCFG) and P0L5:P0L.2 (SMOD) is
latched in on a hardware triggered reset only and will not be evaluated by the
C165H on a software and/or WDT reset.
The configuration via P0H is latched in register RP0H for subsequent evaluation by
software. Register RP0H is described in chapter “The External Bus Interface”.
Note: The reset configuration needs to be held on port P0 throughout the start-up phase
until the C165H takes over control of the external XBUS. This is first indicated by
driving the XBUS output lines ALE, RD, WR/WRL, CS, P4, P1H and P1L. Since it
might prove infeasible to detect the change from tristate to a strongly driven value,
the first rising edge of ALE can be used for indication of the end of the reset
configuration hold time. The first rising edge of ALE occurs 4 CPU cycles after
taking control of the external bus.
The following describes the different selections that are offered for reset configuration.
The default modes refer to pins at high level, ie. without external pulldown devices
connected. Table 74 shows a summary of all modes, supported by the C165H.
Note: The Emulation Mode, known from other C16x Infineon devices, is not supported
by the C165H. Make sure, on pin P0L.0 a HIGH signal is always latched in. HIGH
’1’
ADPWRC
L.5 L.4 L.3 L.2 L.1 L.0H.3 H.2 H.1 H.0 L.7 L.6H.7 H.6 H.5 H.4
CSSELSALSEL BUSTYP
RP0H
Port 4
Logic Port 6
Logic
SYSCON BUSCON0
Internal Control Logic
CLKCFG
Clock
Generator
SMOD
P0L.0
must
be ’1’
always
L.5 L.4 L.3 L.2 L.1 L.0H.3 H.2 H.1 H.0 L.7 L.6H.7 H.6 H.5 H.4
L.1 L.0H.3 H.2 H.1 H.0 L.7 L.6H.4
Configuration latched in on hardware reset
Configuration latched in on software and/or WDT reset
C165H
System Reset
Data Sheet 407 2001-04-19
PRELIMINARY
- EXCERPT -
on P0L.0 is the default configuration and is supported by the internal pull-up
device.
Adapt Mode
Pin P0L.1 (ADP) selects the Adapt Mode when low during reset. It is latched with the
rising edge of RSTIN. In this mode, the C165H goes into a passive state, which is similar
to its state during reset. The pins of the C165H float to tristate or are deactivated via
internal pullup/pulldown devices, as described for the reset state. In addition also the
RSTOUT pin floats to tristate rather than be driven low, and the on-chip oscillator is
switched off.
This mode allows switching a C165H that is mounted to a board virtually off, so an
emulator may control the board’s circuitry, even though the original C165H remains in its
place. The original C165H also may resume to control the board after a reset sequence
with P0L.1 high.
Default: Adapt Mode is off.
Bootstrap Loader Mode
Pin P0L.4 (BSL) activates the on-chip bootstrap loader, when low during reset. The
bootstrap loader allows moving the start code into the internal RAM of the C165H via the
serial interface ASC. The C165H will remain in bootstrap loader mode until a hardware
reset with P0L.4 high or a software reset.
Default: The C165H starts fetching code from location 00’0000H, the bootstrap loader is
off.
External Bus Type
Pins P0L.7 and P0L.6 (BUSTYP) select the external bus type during reset, if an external
start is selected via pin EA. This allows the configuration of the external bus interface of
the C165H even for the first code fetch after reset. The two bits are copied into bit field
BTYP of register BUSCON0. P0L.7 controls the data bus width, while P0L.6 controls the
Table 74 C165H’s Supported Modes and Related Reset Configurations
P0L.5 : P0L.2
(SMOD)
P0L.1 (ADP) Selected Mode
x x x x 0 Adapt Mode
1 1 1 1 1 Normal Mode
0 0 0 1 1 Internal Boot-ROM Read-Out
1 0 1 1 1 Bootstrap-Loader Mode
1 1 0 1 1 Selftest
C165H
System Reset
Data Sheet 408 2001-04-19
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address output (multiplexed or demultiplexed). This bit field may be changed via
software after reset, if required.
PORT0 and PORT1 are automatically switched to the selected bus mode. In multiplexed
bus modes PORT0 drives both the 16-bit intra-segment address and the output data,
while PORT1 remains in high impedance state as long as no demultiplexed bus is
selected via one of the BUSCON registers. In demultiplexed bus modes PORT1 drives
the 16-bit intra-segment address, while PORT0 or P0L (according to the selected data
bus width) drives the output data.
For a 16-bit data bus BHE is automatically enabled, for an 8-bit data bus BHE is disabled
via bit BYTDIS in register SYSCON.
Default: 16-bit data bus with multiplexed addresses.
Note: If an internal start is selected via pin EA, these two pins are disregarded and bit
field BTYP of register BUSCON0 is cleared.
Write Configuration
Pin P0H.0 (WRC) selects the initial operation of the control pins WR and BHE during
reset. When high, this pin selects the standard function, ie. WR control and BHE. When
low, it selects the alternate configuration, ie. WRH and WRL. Thus even the first access
after a reset can go to a memory controlled via WRH and WRL. This bit is latched in
register RP0H and its inverted value is copied into bit WRCFG in register SYSCON.
Default: Standard function (WR control and BHE).
Chip Select Lines
Pins P0H.2 and P0H.1 (CSSEL) define the number of active chip select signals during
reset. This allows the selection which pins of Port 6 drive external CS signals and which
are used for general purpose IO. The two bits are latched in register RP0H.
Default: All 5 chip select lines active (CS4...CS0).
BTYP
Encoding
External Data Bus Width External Address Bus Mode
0 0 8-bit Data Demultiplexed Addresses
0 1 8-bit Data Multiplexed Addresses
1 0 16-bit Data Demultiplexed Addresses
1 1 16-bit Data Multiplexed Addresses
CSSEL Chip Select Lines Note
1 1 Five: CS4...CS0 Default without pull-downs
1 0 None Port 6 pins free for I/O
C165H
System Reset
Data Sheet 409 2001-04-19
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Note: The selected number of CS signals cannot be changed via software after reset.
Segment Address Lines
Pins P0H.4 and P0H.3 (SALSEL) define the number of active segment address lines
during reset. This allows the selection which pins of Port 4 drive address lines and which
are used for general purpose IO. The two bits are latched in register RP0H. Depending
on the system architecture the required address space is chosen and accessible right
from the start, so the initialization routine can directly access all locations without prior
programming. The required pins of Port 4 are automatically switched to address output
mode.
Even if not all segment address lines are enabled on Port 4, the C165H internally uses
its complete 24-bit addressing mechanism. This allows the restriction of the width of the
effective address bus, while still deriving CS signals from the complete addresses.
Default: 2-bit segment address (A17...A16) allowing access to 256 KByte.
Note: The selected number of segment address lines cannot be changed via software
after reset.
Clock Generation Control
Pins P0H.7, P0H.6 and P0H.5 (CLKCFG) select the clock generation mode (on-chip
PLL) during reset. Please refer to Chapter 3.3, "Clock Generation Concept".
0 1 Two: CS1...CS0 P6.4..P6.2 free for GPI/O
0 0 Three: CS2...CS0 P6.4..P6.3 free for GPI/O
SALSEL Segment Address Lines Directly accessible Address Space
1 1 Two: A17...A16 256 KByte (Default without pull-downs)
1 0 Eight: A22...A16 8 MByte (Maximum)
0 1 None 64 KByte (Minimum)
0 0 Four: A19...A16 1 MByte
CSSEL Chip Select Lines Note
C165H
Power Reduction Modes
Data Sheet 410 2001-04-19
PRELIMINARY
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18 Power Reduction Modes
Two different power reduction modes with different levels of power reduction have been
implemented in the C165H, which may be entered under software control.
In Idle mode the CPU is stopped, while the peripherals continue their operation. Idle
mode can be terminated by any reset or interrupt request.
In Power Down mode both the CPU and the peripherals are stopped. Power Down
mode can only be terminated by a hardware reset.
Note: All external bus actions are completed before Idle or Power Down mode is
entered. However, Idle or Power Down mode is not entered if READY is enabled,
but has not been activated (driven low) during the last bus access.
18.1 Idle Mode
The power consumption of the C165H microcontroller can be decreased by entering Idle
mode. In this mode all peripherals, including the watchdog timer, continue to operate
normally, only the CPU operation is halted.
Idle mode is entered after the IDLE instruction has been executed and the instruction
before the IDLE instruction has been completed. To prevent unintentional entry into Idle
mode, the IDLE instruction has been implemented as a protected 32-bit instruction.
Idle mode is terminated by interrupt requests from any enabled interrupt source whose
individual Interrupt Enable flag was set before the Idle mode was entered, regardless of
bit IEN.
For a request selected for CPU interrupt service the associated interrupt service routine
is entered if the priority level of the requesting source is higher than the current CPU
priority and the interrupt system is globally enabled. After the RETI (Return from
Interrupt) instruction of the interrupt service routine is executed the CPU continues
executing the program with the instruction following the IDLE instruction. Otherwise, if
the interrupt request cannot be serviced because of a too low priority or a globally
disabled interrupt system the CPU immediately resumes normal program execution with
the instruction following the IDLE instruction.
For a request which was programmed for PEC service a PEC data transfer is performed
if the priority level of this request is higher than the current CPU priority and the interrupt
system is globally enabled. After the PEC data transfer has been completed the CPU
remains in Idle mode. Otherwise, if the PEC request cannot be serviced because of a
too low priority or a globally disabled interrupt system the CPU does not remain in Idle
mode but continues program execution with the instruction following the IDLE
instruction.
C165H
Power Reduction Modes
Data Sheet 411 2001-04-19
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Figure 133 Transitions between Idle mode and active mode
Idle mode can also be terminated by a Non-Maskable Interrupt, ie. a high to low transition
on the NMI pin. After Idle mode has been terminated by an interrupt or NMI request, the
interrupt system performs a round of prioritization to determine the highest priority
request. In the case of an NMI request, the NMI trap will always be entered.
Any interrupt request whose individual Interrupt Enable flag was set before Idle mode
was entered will terminate Idle mode regardless of the current CPU priority. The CPU
will not go back into Idle mode when a CPU interrupt request is detected, even when the
interrupt was not serviced because of a higher CPU priority or a globally disabled
interrupt system (IEN=’0’). The CPU will only go back into Idle mode when the interrupt
system is globally enabled (IEN=’1’) and a PEC service on a priority level higher than
the current CPU level is requested and executed.
Note: An interrupt request which is individually enabled and assigned to priority level 0
will terminate Idle mode. The associated interrupt vector will not be accessed,
however.
The watchdog timer may be used to monitor the Idle mode: an internal reset will be
generated if no interrupt or NMI request occurs before the watchdog timer overflows. To
prevent the watchdog timer from overflowing during Idle mode it must be programmed
to a reasonable time interval before Idle mode is entered.
The standard Idle mode can be additionally configured by programming the SYSCON3
register, using the flexible peripheral management functions. This is especially
advantages, because it is thus possible to activate only these peripherals also in Idle
mode which are really required for standby operation or for wakeup, reducing power
consumption to the absolute minimum for a specific peripheral operation during Idle
mode.
Active
Mode Idle
Mode
IDLE instruction
CPU Interrupt Request
Denied PEC Request Executed
PEC Request
denied
accepted
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Power Reduction Modes
Data Sheet 412 2001-04-19
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18.2 Power Down Mode
To further reduce the power consumption the microcontroller can be switched to Power
Down mode. Clocking of all internal blocks is stopped, the contents of the internal RAM,
however, are preserved through the voltage supplied via the VCC pins. The watchdog
timer is stopped in Power Down mode. This mode can only be terminated by an external
hardware reset, ie. by asserting a low level on the RSTIN pin. This reset will initialize all
SFRs and ports to their default state, but will not change the contents of the internal
RAM.
There are two levels of protection against unintentionally entering Power Down mode.
First, the PWRDN (Power Down) instruction which is used to enter this mode has been
implemented as a protected 32-bit instruction. Second, this instruction is effective only
if the NMI (Non Maskable Interrupt) pin is externally pulled low while the PWRDN
instruction is executed. The microcontroller will enter Power Down mode after the
PWRDN instruction has completed.
This feature can be used in conjunction with an external power failure signal which pulls
the NMI pin low when a power failure is imminent. The microcontroller will enter the NMI
trap routine which can save the internal state into RAM. After the internal state has been
saved, the trap routine may set a flag or write a certain bit pattern into specific RAM
locations, and then execute the PWRDN instruction. If the NMI pin is still low at this time,
Power Down mode will be entered, otherwise program execution continues. During
power down the voltage at the VCC pins can be lowered to 2.5 V while the contents of the
internal RAM will still be preserved.
The initialization routine (executed upon reset) can check the identification flag or bit
pattern within RAM to determine whether the controller was initially switched on, or
whether it was properly restarted from Power Down mode.
18.3 Status of Output Pins during Idle and Power Down Mode
During Idle mode the CPU clocks are turned off, while all peripherals continue their
operation in the normal way. Therefore all ports pins, which are configured as general
purpose output pins, output the last data value which was written to their port output
latches. If the alternate output function of a port pin is used by a peripheral, the state of
the pin is determined by the operation of the peripheral.
Port pins which are used for bus control functions go into that state which represents the
inactive state of the respective function (eg. WR), or to a defined state which is based on
the last bus access (eg. BHE). Port pins which are used as external address/data bus
hold the address/data which was output during the last external memory access before
entry into Idle mode under the following conditions:
P0H outputs the high byte of the last address if a multiplexed bus mode with 8-bit data
bus is used, otherwise P0H is floating. P0L is always floating in Idle mode.
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PORT1 outputs the lower 16 bits of the last address if a demultiplexed bus mode is used,
otherwise the output pins of PORT1 represent the port latch data.
Port 4 outputs the segment address for the last access on those pins that were selected
during reset, otherwise the output pins of Port 4 represent the port latch data.
During Power Down mode the oscillator and the clocks to the CPU and to the
peripherals are turned off. Like in Idle mode, all port pins which are configured as general
purpose output pins output the last data value which was written to their port output
latches.
When the alternate output function of a port pin is used by a peripheral the state of this
pin is determined by the last action of the peripheral before the clocks were switched off.
The table below summarizes the state of all C165H output pins during Idle and Power
Down mode.
Note:
1): High if EINIT was executed before entering Idle or Power Down mode, Low otherwise.
2): For multiplexed buses with 8-bit data bus.
C165H
Output Pin(s)
Idle Mode Power Down Mode
No
external bus
External bus
enabled
No
external bus
External bus
enabled
ALE Low Low Low Low
RD, WR High High High High
CLKOUT Active Active High High
RSTOUT 1) 1) 1) 1)
P0L Port Latch Data Floating Port Latch Data Floating
P0H Port Latch Data A15...A8 2) / Float Port Latch Data A15...A8 2) / Float
PORT1 Port Latch Data Last Address 3) /
Port Latch Data
Port Latch Data Last Address 3) /
Port Latch Data
Port 4 Port Latch Data Port Latch Data/
Last segment
Port Latch Data Port Latch Data/
Last segment
BHE Port Latch Data Last value Port Latch Data Last value
HLDA Port Latch Data Last value Port Latch Data Last value
BREQ Port Latch Data High Port Latch Data High
CSx Port Latch Data Last value 4) Port Latch Data Last value 4)
Other Port
Output Pins
Port Latch Data /
Alternate Function
Port Latch Data /
Alternate Function
Port Latch Data /
Alternate Function
Port Latch Data /
Alternate Function
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3): For demultiplexed buses.
4): The CS signal that corresponds to the last address remains active (low), all other enabled CS signals
remain inactive (high). By accessing an on-chip X-Periperal prior to entering a power save mode all
external CS signals can be deactivated.
18.4 Extended Power Management
Infineon Technologies C16x’s well known basic power reduction modes (Idle and Power
Down) are enhanced by a number of additional power management features. These
features can be combined or selectively used to reduce the controller’s power
consumption to the respective application’s possible minimum. According to the sense
of platform modularity, the extended power management functions are controlled by
different submodules and registers, as follows::
The C165H’s power management functions can be supplemented by the Real Time
Clock (RTC) timer with optional periodic wakeup from Sleep or Idle mode. The periodic
wakeup combines the drastically reduced power consumption in power reduction modes
(in conjunction with the additional power management features) with a high level of
system availability. External signals and events can be scanned (at a lower rate) by
periodically activating the CPU and selected peripherals which then return to powersave
mode after a short time. This greatly reduces the system’s average power consumption.
The RTC is fully controlled by the C165H’s power reduction submodules.
The Extended Power Management Module controls the Sleep mode. The Sleep mode is
a new power management function which represents and is equal to a Power Down
mode but with exit/wakeup handling as in Idle mode. Wakeup out of Sleep state is
possible with all external interrupts (including alternate sources e.g. from ASC interface),
with NMI and with RTC interrupts. As in Idle mode also PEC requests are executed in
Sleep mode, resulting in an interruption and resumption of Sleep mode. The watchdog
timer is stopped in Sleep mode. The contents of internal RAM and of CBC’s registers are
preserved through the voltage supplied via the VDD pins.
As in Power Down mode, the Sleep mode may also be combined with a running real time
clock RTC. In Sleep mode the oscillators (RTC and selected oscillator optionally), the
PLL as well as the whole clock system is stopped as in power down state. This implies
- contrary to Idle mode - , that after wakeup the exit of Sleep mode and thus the start of
any CPU operation is normally delayed by the ramp-up time of the clock system
Sub Module Control Register
Extended Power Management /Sleep Mode Control SYSCON1
Flexible Clock Generation Management SYSCON2
Flexible Peripheral Management SYSCON3
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(oscillator, PLL). Only when the PLL clock is locked on configured frequency, the system
clock is started and the following processing is identical to wakeup from Idle mode.
For description of Idle mode and its possibilities of configuration see Chapter 18.1, "Idle
Mode".
Register in Extended Power Management Module :
Note: SYSCON1 is a protected register; its security level is automatically set to full write
protection after execution of EINIT instruction.
The power reduction modes Idle and power down are extended by the Infineons C16x
devices newly introduced sleep mode.
18.4.1 Sleep Mode
The Sleep mode is a new power management function which represents and is equal to
a Power Down mode but with exit/wakeup handling as in Idle mode. Wakeup from Sleep
state is possible with all external interrupts (including alternate sources e.g. from SSC
interface), with NMI and with RTC interrupts. As in Idle mode also PEC requests are
executed in Sleep mode, resulting in an interruption and resumption of Sleep mode. The
watchdog timer is stopped in Sleep mode. The contents of internal RAM and registers
are preserved through the voltage supplied via the VDD pins.
Generally, the external bus and the XBUS are released during Sleep mode if enabled by
the Hold Enable bit HLDEN in the last Program Status Word PSW. If enabled, the signal
HLDA is active as long as the Sleep mode (as well as the Idle or Power Down mode) is
active. Only when the clock is available again after wakeup, the HOLD request signal is
sampled and the HLDA state continued until HOLD is deactivated.
As in Power Down mode, the Sleep mode may also be combined with a running real time
clock RTC. In Sleep mode the oscillators (RTC and selected oscillator optionally), the
PLL as well as the whole clock system is stopped as in Power Down state. This implies,
that after wakeup the exit of Sleep mode normally is delayed by the ramp-up time of the
clock system (oscillator, PLL).
Sleep mode is entered after the standard IDLE instruction (protected 32 bit instruction)
has been executed and the instruction before the IDLE instruction has been completed.
The selection between standard Idle mode and Sleep mode is controlled with the new
register SYSCON1 (see below).
Note: Sleep mode cannot be entered in Slow Down mode - the start of sleep mode and
wakeup is only possible in the normal clocking mode (PLL or direct drive) as
defined with the startup configuration on port P0. If Sleep mode shall be entered
Register Description
SYSCON1 System configuration control register for sleep management
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during Slow Down mode, automatically the standard Idle mode is selected as
configured with SYSCON3 register.
The Sleep mode is controlled by bitfield SLEEPCON within register SYSCON1.
SYSCON1 (F1DCH / EEH) ESFR-b Reset Value: 0000H
Note: SYSCON1 is write protected after the execution of EINIT unless it is released via
the unlock sequence.
General description of SYSCON1 bits:
Before entering Sleep mode with the IDLE instruction, the continuation of instruction
processing after termination of Sleep mode must be prepared as known from standard
Idle mode. For wakeup with interrupt, four general possibilities of continuation can be
selected, which are controlled (prepared) as follows:
•Continuation with first instruction after the IDLE instruction will be enabled if
–interrupts are globally disabled with the Interrupt Enable bit in PSW, or
–the interrupt is enabled by global (PSW) and by individual (interrupt control register)
enable bit, but the current CPU priority level (in PSW) of IDLE instruction is higher
than the interrupt level.
•Continuation with first instruction of dedicated interrupt service routine will be
selected if
the interrupt is enabled by global (in PSW) and by individual (interrupt control register)
enable bit, and the CPU priority level of IDLE instruction is lower than the interrupt
level, thus the enabled interrupt has highest priority. Additionally, PEC Transfer for this
interrupt is not enabled. The continuation with the dedicated service routine is always
performed in case of NMI hardware traps, independently of any enable bit or CPU
priority level.
•Execution of one PEC Transfer and resumption of Sleep mode will be selected if
the interrupt is enabled by global (in PSW) and by individual (interrupt control register)
enable bit, and the CPU priority level of IDLE instruction is lower than the interrupt
Bit Function
SLEEPCON SLEEP Mode Configuration
‘0 0’: normal IDLE mode
‘0 1’: SLEEP mode with running RTC
‘1 0’: reserved
‘1 1’: SLEEP mode with stopped RTC and stopped OSC
- ------ - --
54321011 10 987615 14 13 12
--- rw-------
-SLEEPCON
-- -rw
-
--
-
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level, thus the enabled interrupt has highest priority. Additionally, PEC Transfer for this
interrupt is enabled.
•Continuation with standard Idle mode as configured with register SYSCON3 if
the interrupt is not enabled with the individual Interrupt Enable flag in its interrupt
control register. Note: In standard Idle mode the watchdog timer has to be serviced.
For description of SYSCON3 see ´description of Peripheral Management Module.
As wakeup from Idle mode, wakeup from Sleep mode is performed with any enabled
interrupt request. Sleep mode is terminated and the before selected (and above
described) continuation of processing is executed, if one of the following interrupts occur:
•Fast External Interrupts (EXxINT). All fast external interrupts can be selected for
wakeup from Sleep mode by defining the related trigger transitions (edges) in the
EXICON register. All transition types are allowed also in Sleep mode.
•Alternate sources for Fast External Interrupts (EXxINT) as defined by the EXISEL
register. If selected, transitions on receive lines of serial interface controllers (ASC,
SSC, IOM-2) can be used for wakeup from Sleep mode.
•RTC Timer T14 cyclic interrupt. For waking up from Sleep mode via RTC T14
interrupt, the RTC operation during Sleep mode must be selected in bitfield
SLEEPCON within register SYSCON1. Additionally, the RTC interrupt must be
enabled in the Interrupt Subnode Control register ISNC.
•RTC interrupt(s). With new real time clock, additional RTC interrupts can be enabled
via the Interrupt Subnode Control register RTCISNC. For wakeup, RTC operation
during Sleep mode must be selected in SYSCON1. This function is not supported in
C167CS.
•Non-Maskable Interrupt NMI. A high-to-low transition on NMI pin always terminates
the Sleep mode. The NMI input is filtered for spike suppression. (Planned: Input
signals shorter than 10ns are suppressed, detection is guaranteed for minimum 150ns
NMI signal).
Setup Lengthening Control (Start Delay)
Contrary to Idle mode, after wakup from Sleep mode at first the ramp-up of clock system
(oscillator and PLL) has to be controlled before any CPU operation can be started. Only
when the clock system is locked on configured frequency, the following processing is
identical to wakeup from Idle mode.
Note: This setup lengthening function is very similar to the start delay after HW-reset
because of reset lengthening conditions (see reset section). Setup lengthening
uses the same lengthening control signals as reset lengthening, but after setup the
program start is controlled with the trailing edge of a setup-active signal (contrary
to the RST signal in case of reset lengthening) which is provided to the core to
delay the execution of first instruction. The system hold state during setup is
controlled by start delay of clock distribution.
C165H
System Control Unit (CSCU)
Data Sheet 418 2001-04-19
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19 System Control Unit (CSCU)
19.1 Introduction
The System Control Unit CSCU is used to control system specific tasks such as reset
control or power management (see previous Chapter "Power Reduction Modes") within
an on-chip system build around the Infineons Cell-Based Core C166. The power
management features of the CSCU provide effective means to realize standby
conditions for the system with an optimum balance between power reduction, peripheral
operation and system functionality. Additionally, the CSCU controls the modes and
operation of Real Time Clock RTC.
Summary of Features and Functions
The CSCU is characterized by the following functions:
• Central Control of system operation
– External interrupt and frequency output control
– Protection management for system control registers
• General XBUS peripherals control
– Control of visibility of XPERs
• Power management additional to the standard Idle and Power Down modes
– Sleep mode with wakeup from Power Down state by external interrupts
• Peripheral Management with individual clock and power control of peripherals
– Control of power down state of Flash modules during Idle
• Flexible clock generation management
– Programmable system Slow Down control with or without PLL
– Control interface for Clock Generation Unit
• Identification register block for chip and CSCU identification
– Device, revision, manufacturer
– CSCU identification register
19.2 Operational Overview
19.2.1 Overview of CSCU submodules
In the following paragraphs a functional overview of the different blocks and submodules
of the System Control Unit is presented.
XBUS Peripheral Configuration Block
In the C165H, XBUS peripherals can be separately switched on or off by programming
the XPERCON register. If switched off, the respective peripheral is not visible, meaning,
that its address space and its functional pins are not occupied.
C165H
System Control Unit (CSCU)
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Note: In parallel to the XPER control with XPERCON register, the visibility of XPER
address spaces also is controlled with the BUSACT bits in respective XBCON
registers (in the C166 core)
Note: The XPER configuration is additionally controlled by means of flexible peripheral
management control (see Peripheral Management Module below) for power
reduction.
Register in XPER Configuration Block:
System Control Block
This block has several system management functions.
The System Control Block controls the system register write protection, introduced for
the system control registers SYSCON1-3.
Note: The new register write protection especially supports modularity of design, and is
therefore not compatible with the previously known C16x release function, using
the release bitfield in SYSCON2 for write protection.
Additional control functions of the System Control Block:
– Control of fast external interrupt inputs
– Control of external interrupt source selection
– Control of interrupt subnode for PLL and realtime clock interrupts
– Control of spike suppression for fast external interrupts and NMI in Sleep mode
– Clock output frequency control
The System Control Block provides the following registers: :
Register Description
XPERCON XBUS peripheral control of XPER visibility
Register Description
SCUSLC SCU security level command register
SCUSLS SCU security level status and password register
EXICON External interrupt control register (see Chapter 6.8.1, page 115)
EXISEL External interrupt source selection control register (see Chapter 6.8.2, page 115)
ISNC Interrupt subnode control register (see Chapter 6.8.3, page 117)
FOCON Frequency output control register
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System Control Unit (CSCU)
Data Sheet 420 2001-04-19
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Identification Register Block
All new derivatives of Infineons C16x microcontroller family provide a set of min. four
identification registers (expandable to eight). These registers offer information on the
chip manufacturer, the chip type and its memory properties.
Identification registers in the ID Block: :
19.3 XBUS Peripheral Configuration Block
The XBUS peripherals can be separately selected for being visible to the user by means
of corresponding selection bits in the XPERCON register. If not selected and therefore
not enabled (not activated with XPERCON bit), the peripheral’s address space including
SFR addresses and port pins are not occupied by the peripheral, thus the peripheral is
not visible and not available. To make an XBUS peripheral visible, its related bit in
XPERCON register must be set before the XPERs are globally enabled with XPEN-bit
in SYSCON register (during system initialization before EINIT instruction).
Note: After reset, no XBUS peripheral is selected in XPERCON register.
The XPERCON register is defined as follows:
Register Description
IDMANUF Manufacturer and department
IDCHIP Identification of device and revision code
IDMEM Identification of on-chip program memory (type, size)
IDPROG Identification of programming/erasing voltage of on-chip program
memory
IDMEM2 Identification of additional EEPROM, OTP, DRAM or Flash memory
XPERCON (F024H / 12H) ESFRReset Value : 0000H
1514131211109876543210
reserved XPER
7
XPER
6
XPER
5reserved
Bit Field Bits Type Value Description
reserved 15..8 rw 0 These bits are reserved and must be set to ’0’.
XPER7 7rw0
1
This bit is reserved and must be set to ’0’.
XPER6 6rw0
1
This bit is reserved and must be set to ’0’.
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System Control Unit (CSCU)
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Note: The CSCU provides per XPERCON bit one enable signal for XPER visibility
control. These enable signals are routed to the core to be combined with
selectable (per module pins) BUSACT functions of XBCON registers.
19.4 System Control Block
19.4.1 Register Write Protection
The System Control Unit CSCU provides two different protection types of registers:
• Unprotected Registers
• Protectable Registers
The unprotected registers allow reading and writing (if not read-only) of register values
without any restrictions. However, the write access of the protectable registers (security
registers) can be programmed for three different modes of security level, whereas the
read access is always unprotected:
• Write Protected Mode
• Low Protected Mode
• Unprotected Mode
In write protected mode the registers can not be accessed by a write command. However
in low protected mode the registers can be written with a special command sequence
(see desription below). If the registers are set to unprotected mode, all write accesses
are possible.
Some register controlled functions and modes which are critical for the C165H’s
operation are locked after the execution of EINIT, so these vital system functions cannot
be changed inadvertently eg. by software errors. However, as these security registers
control also the power management they need to be accessed during operation to select
the appropriate mode.
The switching between the different security levels is controlled by a state machine. Via
a password and a command sequence the security levels can be changed. After reset
always the unprotected mode is automatically selected. The EINIT command switches
the security level automatically to protected mode.
The low protected mode is especially important for a standby state of the application.
This mode allows fast accesses within two commands to the protected registers without
removing the protection completely.
XPER5 5rw0
1
IOM-2 module is not visible
IOM-2 is selected and visible
reserved 4..0 rw 0 These bits are reserved and must be set to Zero
Bit Field Bits Type Value Description
C165H
System Control Unit (CSCU)
Data Sheet 422 2001-04-19
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Security Level Switching
Two registers are provided for switching the security level, the security level command
register SCUSLC and the security level status register SCUSLS . The security level
command register SCUSLC is used to control the state machine for switching the
security level. The SCUSLC register is loaded with the different commands of the
command sequence necessary to control a change of the security level. It is also used
for the one unlock command, which is necessary in the low protected mode to access
one protected register. The commands of the (unlock) command sequence are
characterized by certain pattern words (as AAAAH) or by patterns combined with an 8-
bit password. For command definition see the following state diagram (figure below). The
new password is defined with command 3 and stored in the according 8-bit field in the
SCUSLS register.
The SCUSLC register is defined as follow
SCUSLC (F0C0H / 60H) ESFRReset Value: 0000H
The command definition is described in Figure 134.
The security level status register SCUSLS is a read only register which shows the
current password, the actual security level and the state of the switching statemachine.
The SCUSLS is defined as followes:
SCUSLS (F0C2H / 61H) ESFRReset Value: 0000H
Bit Function
PASSWORD Current Password
54321011 10 987615 14 13 12
rw
COMMAND
54321011 10 987615 14 13 12
r
PASSWORD
rr
STATE SL reserved
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System Control Unit (CSCU)
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The following registers are defined as protected (security) registers:
• SYSCON1
• SYSCON2
• SYSCON3
The following state diagram, Figure 134, shows the state machine for security level
switching and for unlock command execution in low protected mode:
SL Security Level
0 0: Unprotected write mode
0 1: Low protected mode
1 0: Reserved
1 1: Write protected mode
STATE Actual State
0 0 0: Wait for first command (command 0)
0 0 1: Wait for command 1
0 1 0: Wait for command 2
0 1 1: Wait for new security level and for new password (command 3)
1 0 0: Security registers are unlocked; access to one register is possible
( only in low protected mode)
1 0 1: Reserved
1 1 0: Reserved
1 1 1: Reserved
Bit Function
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System Control Unit (CSCU)
Data Sheet 424 2001-04-19
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Figure 134 Statemachine for Security Level Switching
Write Access in Low Protected Mode
The write access in low protected mode is also done via a command sequence. First the
specific command 4 (see figure above) with the current password has to be written to
register SCUSLC. After this command all security registers are unlocked until the next
write access to any CSCU register is done. Read access is always possible to all
registers of the CSCU and will not influence the command sequences. In register
SCUSCS the actual status of the command state machine can always be read.
It is recommendet to use an atomic sequence for all command sequences.
State 0
State 1 State 2
State 3
Reset
Command0
Command1
Command2
Command3
Command2
Command1
or any other CSCU
register write
or any other CSCU
register write access
access
or any other CSCU
register write access
1)
Note : 1)Only if the security level command register is accessed, the new security level
and the new password is valid.
Command
Number
Command
0 AAAAh
1 5554h
296
h + inverse (old) password
3 000b + new level + 000b + new password
48Eh + inverse (new) password: Unlock
security register in low protected mode
State 4
any CSCU
write access
Command4
and low
protected
mode
register
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System Control Unit (CSCU)
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19.4.2 Clock Output Frequency Control
A clock output signal with programmable frequency (fOUT) can be output via pin FOUT.
This clock signal is generated via a reload counter, so the output frequency can be
selected in small steps. An optional toggle latch provides a clock signal with a 50% duty
cycle.
Signal fOUT always provides complete output periods (see Signal Waveforms below):
• When fOUT is started (FOEN-->’1’) FOCNT is loaded from FORV
• When fOUT is stopped (FOEN-->’0’) FOCNT is stopped when fOUT has reached (or is)
’0’.
Figure 135 Clock Output Signal Generation
Register FOCON provides control over the output signal generation.
FOCON (FFAAH / D5H) SFR-b Reset Value: 0000H
Bit Function
FOCNT Frequency Output Counter
FOTL Frequency Output Toggle Latch
Is toggled upon each underflow of FOCNT.
FORV Frequency Output Reload Value
Is copied to FOCNT upon each underflow of FOCNT.
FOSS
FOCNT
fOUT
FORV
MUX
fCPU FOTL
Ctrl.
FOEN
FOTL-FOSSFOEN
54321011 10 987615 14 13 12
rwrw
FOCNT
rwrwrw
FORV
-
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Note: It is not recommended to write to any part of bitfield FOCNT, especially not while
the counter is running. Writing to FOCNT prior to starting the counter is obsolete
because it will immediatley be reloaded from FORV. Writing to FOCNT during
operation may produce uninteded counter values.
Output Frequency Calculation
The output frequency can be calculated as fOUT = fCPU / ( (FORV+1) * 2(1-FOSS) ),
so fOUTmin = fCPU / 128 (FORV = 3FH, FOSS = ’0’),
and fOUTmax = fCPU / 1 (FORV = 00H, FOSS = ’1’).
Figure 136 Signal Waveforms
Note: The output signal (for FOSS=’1’) is high for the duration of 1 fCPU cycle for all reload
values FORV > 0. For FORV = 0 the output signal corresponds to fCPU.
FOSS Frequency Output Signal Select
0: Output of the toggle latch: DC=50%.
1: Output of the reload counter: DC depends on FORV.
FOEN Frequency Output Enable
0: Frequency output generation stops when signal fOUT is/gets low.
1: FOCNT is running, fOUT is gated to pin. 1st reload after 0-1 transition.
Bit Function
fCPU
fOUT
fOUT
1)
2)
1)
2)
1) FOSS=’1’, output of counter
2) FOSS=’0’, output of toggle latch
FOEN-->’1’FOEN-->’0’
(FORV=0)
(FORV=5)
fOUT
1)
2)
(FORV=2)
The counter stops hereThe counter starts here
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Connection to Output
Signal fOUT in the C165H is an alternate function of pin P3.15/CLKOUT/FOUT.
The priority ranking is: P3.15 < FOUT < CLKOUT.
Figure 137 Connection to Port Logic (Functional Approach)
Note: For the generation of fOUT pin FOUT must be switched to output, ie. DP3.15 =’1’.
While fOUT is disabled the pin is controlled by the port latch (see figure above). The
port latch P3.15 must be ’0’ in order to maintain the fOUT inactive level on the pin.
Clock Management Module
Flexible Clock Management
This module especially serves for power management support. Flexible clock
management includes programmable system slow down with additional control of power
down and optional real time clock. The slowdown operation is achieved by dividing the
oscillator clock by a programmable factor (1...32) resulting in a low frequency device
operation which significantly reduces the overall power consumption. The PLL may be
completely switched off in this mode.
This module also controls the oscillator selection (main or auxiliary) for Real Time Clock
and for Slow Down Divider. During Power Down mode, this block controls the operation
of RTC and ports.
The clock generation is controlled via register SYSCON2.
fOUT MUX
fCPU
"1"
Direction
PortLatch
0
1
MUX
0
1
FOUT_active
CLKEN
MUX
0
1
C165H
System Control Unit (CSCU)
Data Sheet 428 2001-04-19
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SYSCON2 (F1D0H / E8H) ESFR-b Reset Value: 0000.0000.UU00.0000B
Note: SYSCON2 is a security register. The security level is automatically set to write
protectection after execution of EINIT.
Note: To be compatibile to Infineon’s C167CR / 167CS, the Power Down Control
PDCON must be programmed to ’10’ (RTC = Off, Ports = On) during the
initialisation phase before the execution of EINIT instruction. The initial state after
reset is so defined that a reset does not interrupt the real time clock.
Bit Function
PDCON Power Down Control (during power down mode)
x0: RTC = Off, Ports = On (default after reset).
x1: RTC = Off, Ports = Off.
In power down mode, the RTC of the C165H is always off. Bit 5 of
SYSCON2 is don’t care.
RCS RTC Clock Source (not affected by a reset)
0: RTC is switched to synchronous mode.
The input is derived from the CPU clock.
1: RTC is switched to asynchronous mode. The input is derived
from the RTC_REF_CLK (oscillator clock).
SCS SDD Clock Source (not affected by a reset)
Has to be set to ’0’.
CLKCON Clock State Control
00: Running on configured basic frequency.
01: Running on slow down frequency, PLL ON.
10: Running on slow down frequency, PLL OFF.
11: Reserved. Do not use this combination.
CLKREL Reload Counter Value for Slowdown Divider
CLKLOCK Clock Signal Status Bit
0: Main oscillator is unstable or PLL is unlocked.
1: Main oscillator is stable and PLL is locked.
RCSSCS
CLK
LOCK
54321011 10 987615 14 13 12
rw rw
rw rw rw
r rw
CLKREL CLKCON reservedPDCON
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System Control Unit (CSCU)
Data Sheet 429 2001-04-19
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19.5 Peripheral Management Module
This module especially serves for power management support, controlling dynamically
the operation and thus the power consumption of the different peripherals on PD Bus
and XBUS. In each situation (eg. several system operating modes, standby, etc.) only
those peripherals may be kept running which are required for the respective functionality.
All others can be switched off. It also allows the operation control of whole groups of
peripherals.
Peripheral’s operation is disabled or enabled by controlling the specific clock input. This
function also is supported in idle and/or slow down mode.
The Real Time Clock (RTC) may be fed by a separate clock driver, so it can be kept
running even in power down mode.
While a peripheral is disabled its output pins remain in the state they had at the time of
disabling.
Note: In contrast to the peripheral management of Infineon’s 16x family the registers of
a disabled module are not accessable. Only the clock control register of the
platform peripheral is accessable. Note, the register access is not compatible to
the C167CS.
The user gets access to the flexible operation control of peripherals via the SYSCON3
register. This register is defined as follows:
SYSCON3 (F1D4H / EAH) ESFR-b Reset Value:0000H
.
Bit Function
PERDISx Peripheral Disable Flag 0 - 14
‘0’: Module is enabled; the peripheral is supplied with the clock signal
‘1’: Module is disabled; the clock input of peripheral is disabled
GRPDIS Peripheral Group Disable Flag (PD-Bus and X-Bus Peripherals)
‘0’: Peripheral clock driver for peripheral group is enabled
‘1’: Peripheral clock driver for peripheral group is disabled
PLLDIS PLL Disable Flag (additional power savings / noise reduction feature)
‘0’: The PLL of the C165H is switched on. This is the default configuration.
‘1’: The PLL is completely switched off. The free running feature and the
oscillator watchdog will not work, since there is no PLL clock at all.
Note: It makes sense to switch off the PLL in direct drive clock mode only.
54321011 10 987615 14 13 12
- - rw rw-rw rwrw rw rw
PER
DIS0
-rw rw rw
PER
DIS1
PER
DIS2
PER
DIS3
reserved
PER
DIS6
PER
DIS7
PER
DIS8
reserved
-
GRP
DIS re-
serv
ed reserved
PLL
DIS
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System Control Unit (CSCU)
Data Sheet 430 2001-04-19
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- EXCERPT -
Note : Please refer to Chapter 9.8, "Initialization of the C165H’s X-peripherals", for complete
register initialization.
Note : SYSCON3 is an security register. The security level is automatically set to write protection
after execution of EINIT
19.6 Identification Registers
19.6.1 Introduction
The C165H provides a set of 5 identification registers that offer information on the chip,
as manufacturer, chip type and its memory properties.
The ID registers are read only registers. A device that incorporates ID registers shall
return D5H as its Bootstrap Loader identification byte. A standardized routine may then
be downloaded which sends the ID registers to the serial interface, so the host gets exact
information about its partner.
19.6.2 ID Register Description
The ID registers are placed in the extended SFR area.
IDMANUF (F07EH / 3FH) ESFR
PERDISx Module Type Module Function (examples for associated peripheral
modules)
0 PD-Bus Unit RTC Real Time Clock
1 PD-Bus Unit ASC USART
2 PD-Bus Unit SSC Synchronous Serial Channel
3PD-Bus Unit GPT12 General Purpose Timer Block
4..5 reserved - Reserved, has to be set to ’0’.
6X-Bus Unit IOM-2 IOM-2 Interface
7reserved - Reserved, has to be set to ’0’.
8reserved -Reserved, has to be set to ’0’.
9..14 reserved - Reserved, has to be set to ’0’.
54321011 10 987615 14 13 12
rr
MANUF DEPT
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System Control Unit (CSCU)
Data Sheet 431 2001-04-19
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IDCHIP (F07CH / 3EH) ESFR
IDMEM (F07AH / 3DH) ESFR
Bit Function
MANUF Manufacturer
0C1H: Infineon Technologies JEDEC normalized manufacturer code
DEPT Department
04H: Infineon’s Datacom Department
Bit Function
Revision Device Revision Code
03H: actual device revision code
CHIPID Device Identification
05H: Infineons C16x device identification
Bit Function
Size Size of on-chip Program Memory
The size of the implemented program memory in terms of 4 K blocks, i.e..
Memory-size = <Size>*4 KByte.
000H: No program memory on the C165H.
Type Type of on-chip Program Memory
Identifies the memory type on this silicon.
0H: ROMless 1H: Mask ROM
2H: EPROM 3H:Flash
4H:OTP 5
H: EEPROM
6H: DRAM/SRAM
54321011 10 987615 14 13 12
rr
CHIPID Chip Revision Number
54321011 10 987615 14 13 12
rr
Type (’0H’)Size (’000H’)
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System Control Unit (CSCU)
Data Sheet 432 2001-04-19
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IDPROG (F078H / 3CH) ESFR
IDMEM2 (F076H / 3BH) ESFR
Note: IDMEM2 describes the second block of (program) memory. This register is
dedicated to other Infineon devices containing Flash, EEPROM or DRAM
sections. Static RAM modules are not described with ID registers. Since there is
no program memory on the C165H, IDMEM2 is set to ’0000H’.
Bit Function
PROGVDD Programming VDD Voltage
The voltage of the standard power supply pins required when programming or
erasing (if applicable) the on-chip program memory.
Formula: VDD = 20*<PROGVDD> / 256 [V]
00H: No program memory on the C165H.
PROGVPP Programming VPP Voltage
The voltage of the special programming power supply (if existent) required to
program or erase (if applicable) the on-chip program memory.
Formula: VPP = 20*<PROGVPP> / 256 [V]
00H: No program memory on the C165H.
54321011 10 987615 14 13 12
rr
PROGVPP (’00H’)PROGVDD (’00H’)
54321011 10 987615 14 13 12
rr
Type (’0H’)Size (’000H’)
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System Programming
Data Sheet 433 2001-04-19
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20 System Programming
To aid in software development, a number of features has been incorporated into the
instruction set of the C165H, including constructs for modularity, loops, and context
switching. In many cases commonly used instruction sequences have been simplified
while providing greater flexibility. The following programming features help to fully utilize
this instruction set.
Instructions Provided as Subsets of Instructions
In many cases, instructions found in other microcontrollers are provided as subsets of
more powerful instructions in the C165H. This allows the same functionality to be
provided while decreasing the hardware required and decreasing decode complexity. In
order to aid assembly programming, these instructions, familiar from other
microcontrollers, can be built in macros, thus providing the same names.
Directly Substitutable Instructions are instructions known from other microcontrollers
that can be replaced by the following instructions of the C165H:
Modification of System Flags is performed using bit set or bit clear instructions (BSET,
BCLR ). All bit and word instructions can access the PSW register, so no instructions like
CLEAR CARRY or ENABLE INTERRUPTS are required.
External Memory Data Access does not require special instructions to load data
pointers or explicitly load and store external data. The C165H provides a Von-Neumann
memory architecture and its on-chip hardware automatically detects accesses to internal
RAM, GPRs, and SFRs.
Multiplication and Division
Multiplication and division of words and double words is provided through multiple cycle
instructions implementing a Booth algorithm. Each instruction implicitly uses the 32-bit
register MD (MDL = lower 16 bits, MDH = upper 16 bits). The MDRIU flag (Multiply or
Divide Register In Use) in register MDC is set whenever either half of this register is
written to or when a multiply/divide instruction is started. It is cleared whenever the MDL
Substituted Instruction C165H Instruction Function
CLR Rn AND Rn, #0HClear register
CPLB Bit BMOVN Bit, Bit Complement bit
DEC Rn SUB Rn, #1HDecrement register
INC Rn ADD Rn, #1HIncrement register
SWAPB Rn ROR Rn, #8HSwap bytes within word
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register is read. Because an interrupt can be acknowledged before the contents of
register MD are saved, this flag is required to alert interrupt routines, which require the
use of the multiply/divide hardware, so they can preserve register MD. This register,
however, only needs to be saved when an interrupt routine requires use of the MD
register and a previous task has not saved the current result. This flag is easily tested by
the Jump-on-Bit instructions.
Multiplication or division is simply performed by specifying the correct (signed or
unsigned) version of the multiply or divide instruction. The result is then stored in register
MD. The overflow flag (V) is set if the result from a multiply or divide instruction is greater
than 16 bits. This flag can be used to determine whether both word halfs must be
transferred from register MD. The high portion of register MD (MDH) must be moved into
the register file or memory first, in order to ensure that the MDRIU flag reflects the correct
state.
The following instruction sequence performs an unsigned 16 by 16-bit multiplication:
SAVE:
JNB MDRIU, START ;Test if MD was in use.
SCXT MDC, #0010H ;Save and clear control register,
;leaving MDRIU set
;(only required for interrupted
;multiply/divide instructions)
BSET SAVED ;Indicate the save operation
PUSH MDH ;Save previous MD contents...
PUSH MDL ;...on system stack
START:
MULU R1, R2 ;Multiply 16·16 unsigned, Sets MDRIU
JMPR cc_NV, COPYL ;Test for only 16-bit result
MOV R3, MDH ;Move high portion of MD
COPYL:
MOV R4, MDL ;Move low portion of MD, Clears MDRIU
RESTORE:
JNB SAVED, DONE ;Test if MD registers were saved
POP MDL ;Restore registers
POP MDH
POP MDC
BCLR SAVED ;Multiplication is completed,
;program continues
DONE: ...
The above save sequence and the restore sequence after COPYL are only required if
the current routine could have interrupted a previous routine which contained a MUL or
DIV instruction. Register MDC is also saved because it is possible that a previous
routine's Multiply or Divide instruction was interrupted while in progress. In this case the
information about how to restart the instruction is contained in this register. Register
MDC must be cleared to be correctly initialized for a subsequent multiplication or
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division. The old MDC contents must be popped from the stack before the RETI
instruction is executed.
For a division the user must first move the dividend into the MD register. If a 16/16-bit
division is specified, only the low portion of register MD must be loaded. The result is also
stored into register MD. The low portion (MDL) contains the integer result of the division,
while the high portion (MDH) contains the remainder.
The following instruction sequence performs a 32 by 16-bit division:
MOV MDH, R1 ;Move dividend to MD register. Sets MDRIU
MOV MDL, R2 ;Move low portion to MD
DIV R3 ;Divide 32/16 signed, R3 holds divisor
JMPR cc_V, ERROR ;Test for divide overflow
MOV R3, MDH ;Move remainder to R3
MOV R4, MDL ;Move integer result to R4. Clears MDRIU
Whenever a multiply or divide instruction is interrupted while in progress, the address of
the interrupted instruction is pushed onto the stack and the MULIP flag in the PSW of the
interrupting routine is set. When the interrupt routine is exited with the RETI instruction,
this bit is implicitly tested before the old PSW is popped from the stack. If MULIP=’1’ the
multiply/divide instruction is re-read from the location popped from the stack (return
address) and will be completed after the RETI instruction has been executed.
Note: The MULIP flag is part of the context of the interrupted task. When the
interrupting routine does not return to the interrupted task (eg. scheduler switches
to another task) the MULIP flag must be set or cleared according to the context of
the task that is switched to.
BCD Calculations
No direct support for BCD calculations is provided in the C165H. BCD calculations are
performed by converting BCD data to binary data, performing the desired calculations
using standard data types, and converting the result back to BCD data. Due to the
enhanced performance of division instructions binary data is quickly converted to BCD
data through division by 10D. Conversion from BCD data to binary data is enhanced by
multiple bit shift instructions. This provides similar performance compared to instructions
directly supporting BCD data types, while no additional hardware is required.
20.1 Stack Operations
The C165H supports two types of stacks. The system stack is used implicitly by the
controller and is located in the internal RAM. The user stack provides stack access to the
user in either the internal or external memory. Both stack types grow from high memory
addresses to low memory addresses.
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Data Sheet 436 2001-04-19
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Internal System Stack
A system stack is provided to store return vectors, segment pointers, and processor
status for procedures and interrupt routines. A system register, SP, points to the top of
the stack. This pointer is decremented when data is pushed onto the stack, and
incremented when data is popped.
The internal system stack can also be used to temporarily store data or pass it between
subroutines or tasks. Instructions are provided to push or pop registers on/from the
system stack. However, in most cases the register banking scheme provides the best
performance for passing data between multiple tasks.
Note: The system stack allows the storage of words only. Bytes must either be
converted to words or the respective other byte must be disregarded.
Register SP can only be loaded with even byte addresses (The LSB of SP is
always '0').
Detection of stack overflow/underflow is supported by two registers, STKOV (Stack
Overflow Pointer) and STKUN (Stack Underflow Pointer). Specific system traps (Stack
Overflow trap, Stack Underflow trap) will be entered whenever the SP reaches either
boundary specified in these registers.
The contents of the stack pointer are compared to the contents of the overflow register,
whenever the SP is DECREMENTED either by a CALL, PUSH or SUB instruction. An
overflow trap will be entered, when the SP value is less than the value in the stack
overflow register.
The contents of the stack pointer are compared to the contents of the underflow register,
whenever the SP is INCREMENTED either by a RET, POP or ADD instruction. An
underflow trap will be entered, when the SP value is greater than the value in the stack
underflow register.
Note: When a value is MOVED into the stack pointer, NO check against the overflow/
underflow registers is performed.
In many cases the user will place a software reset instruction (SRST) into the stack
underflow and overflow trap service routines. This is an easy approach, which does not
require special programming. However, this approach assumes that the defined internal
stack is sufficient for the current software and that exceeding its upper or lower boundary
represents a fatal error.
It is also possible to use the stack underflow and stack overflow traps to cache portions
of a larger external stack. Only the portion of the system stack currently being used is
placed into the internal memory, thus allowing a greater portion of the internal RAM to
be used for program, data or register banking. This approach assumes no error but
requires a set of control routines (see below).
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Circular (virtual) Stack
This basic technique allows pushing until the overflow boundary of the internal stack is
reached. At this point a portion of the stacked data must be saved into external memory
to create space for further stack pushes. This is called “stack flushing”. When executing
a number of return or pop instructions, the upper boundary (since the stack empties
upward to higher memory locations) is reached. The entries that have been previously
saved in external memory must now be restored. This is called “stack filling”. Because
procedure call instructions do not continue to nest infinitely and call and return
instructions alternate, flushing and filling normally occurs very infrequently. If this is not
true for a given program environment, this technique should not be used because of the
overhead of flushing and filling.
The basic mechanism is the transformation of the addresses of a virtual stack area,
controlled via registers SP, STKOV and STKUN, to a defined physical stack area within
the internal RAM via hardware. This virtual stack area covers all possible locations that
SP can point to, ie. 00’F000H through 00’FFFEH. STKOV and STKUN accept the same
4 KByte address range.
The size of the physical stack area within the internal RAM that effectively is used for
standard stack operations is defined via bitfield STKSZ in register SYSCON (see below).
The virtual stack addresses are transformed to physical stack addresses by
concatenating the significant bits of the stack pointer register SP (see table) with the
complementary most significant bits of the upper limit of the physical stack area
(00’FBFEH). This transformation is done via hardware (see figure below).
<STKSZ> Stack Size
(Words)
Internal RAM Addresses (Words)
of Physical Stack
Significant Bits of
Stack Pointer SP
0 0 0 B256 00’FBFEH...00’FA00H (Default after Reset) SP.8...SP.0
0 0 1 B128 00’FBFEH...00’FB00HSP.7...SP.0
0 1 0 B64 00’FBFEH...00’FB80HSP.6...SP.0
0 1 1 B32 00’FBFEH...00’FBC0HSP.5...SP.0
1 0 0 B512 00’FBFEH...00’F800H (not for 1 Kbyte IRAM) SP.9...SP.0
1 0 1 B--- Reserved. Do not use this combination. ---
1 1 0 B--- Reserved. Do not use this combination. ---
1 1 1 B1024 00’FDFEH...00’FX00H (Note: No circular
stack)
00’FX00H represents the lower IRAM limit, ie.
1 KB: 00’FA00H, 2 KB: 00’F600H, 3 KB:
00’F200H
SP.11...SP.0
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The reset values (STKOV=FA00H, STKUN=FC00H, SP=FC00H, STKSZ=000B) map the
virtual stack area directly to the physical stack area and allow using the internal system
stack without any changes, provided that the 256 word area is not exceeded.
Figure 138 Physical Stack Address Generation
The following example demonstrates the circular stack mechanism which is also an
effect of this virtual stack mapping: First, register R1 is pushed onto the lowest physical
stack location according to the selected maximum stack size. With the following
instruction, register R2 will be pushed onto the highest physical stack location although
the SP is decremented by 2 as for the previous push operation.
MOV SP, #0F802H ;Set SP before last entry...
;...of physical stack of 256 words
... ;(SP)=F802H: Physical stack addr.=FA02H
PUSH R1 ;(SP)=F800H: Physical stack addr.=FA00H
PUSH R2 ;(SP)=F7FEH: Physical stack addr.=FBFEH
The effect of the address transformation is that the physical stack addresses wrap
around from the end of the defined area to its beginning. When flushing and filling the
internal stack, this circular stack mechanism only requires to move that portion of stack
1 1 1 1 1 0 1 1 1 1 1 1 1 1 1 0
1 1 1 1 1 0 1 1 1 0 0 0 0 0 0 0
1 1 1 1 1 0 1 1 1 0 0 0 0 0 0 0 1 1 1 1 1 0 1 0 0 0 0 0 0 0 0 0
1 1 1 1 1 0 1 1 1 1 1 1 1 1 1 0
1 1 1 1 1 0 1 1 0 1 1 1 1 1 1 0
1 1 1 1 1 0 1 1 1 1 1 1 1 1 1 0
FBFEH
FB80H
FB80H
FBFEH
FB7EH
FBFEH
FBFEH
64 words 256 words
F800H1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0
FA00H
1 1 1 1 0 1 1 1 1 1 1 1 1 1 1 0
1 1 1 1 1 0 1 1 1 1 1 1 1 1 1 0
FBFEH
F7FEH
FBFEH
1 1 1 1 1 0 1 1 1 1 1 1 1 1 1 0
1 1 1 1 1 0 1 1 1 1 1 1 1 1 1 0
<SP>
<SP>
Phys.A.
Phys.A.
Stack Size
After PUSH After PUSH
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data which is really to be re-used (ie. the upper part of the defined stack area) instead of
the whole stack area. Stack data that remain in the lower part of the internal stack need
not be moved by the distance of the space being flushed or filled, as the stack pointer
automatically wraps around to the beginning of the freed part of the stack area.
Note: This circular stack technique is applicable for stack sizes of 32 to 512 words
(STKSZ = ‘000B’ to ‘100B’), it does not work with option STKSZ = ‘111B’, which
uses the complete internal RAM for system stack.
In the latter case the address transformation mechanism is deactivated.
When a boundary is reached, the stack underflow or overflow trap is entered, where the
user moves a predetermined portion of the internal stack to or from the external stack.
The amount of data transferred is determined by the average stack space required by
routines and the frequency of calls, traps, interrupts and returns. In most cases this will
be approximately one quarter to one tenth the size of the internal stack. Once the transfer
is complete, the boundary pointers are updated to reflect the newly allocated space on
the internal stack. Thus, the user is free to write code without concern for the internal
stack limits. Only the execution time required by the trap routines affects user programs.
The following procedure initializes the controller for usage of the circular stack
mechanism:
• Specify the size of the physical system stack area within the internal RAM (bitfield
STKSZ in register SYSCON).
• Define two pointers, which specify the upper and lower boundary of the external stack.
These values are then tested in the stack underflow and overflow trap routines when
moving data.
• Set the stack overflow pointer (STKOV) to the limit of the defined internal stack area
plus six words (for the reserved space to store two interrupt entries).
The internal stack will now fill until the overflow pointer is reached. After entry into the
overflow trap procedure, the top of the stack will be copied to the external memory. The
internal pointers will then be modified to reflect the newly allocated space. After exiting
from the trap procedure, the internal stack will wrap around to the top of the internal
stack, and continue to grow until the new value of the stack overflow pointer is reached.
When the underflow pointer is reached while the stack is meptied the bottom of stack is
reloaded from the external memory and the internal pointers are adjusted accordingly.
Linear Stack
The C165H also offers a linear stack option (STKSZ = ‘111B’), where the system stack
may use the complete internal RAM area. This provides a large system stack without
requiring procedures to handle data transfers for a circular stack. However, this method
also leaves less RAM space for variables or code. The RAM area that may effectively be
consumed by the system stack is defined via the STKUN and STKOV pointers. The
underflow and overflow traps in this case serve for fatal error detection only.
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For the linear stack option all modifiable bits of register SP are used to access the
physical stack. Although the stack pointer may cover addresses from 00’F000H up to
00’FFFEH the (physical) system stack must be located within the internal RAM and
therefore may only use the address range 00’F600H to 00’FDFEH. It is the user’s
responsibility to restrict the system stack to the internal RAM range.
Note: Avoid stack accesses below the IRAM area (ESFR space and reserved area) and
within address range 00’FE00H and 00’FFFEH (SFR space).
Otherwise unpredictable results will occur.
User Stacks
User stacks provide the ability to create task specific data stacks and to off-load data
from the system stack. The user may push both bytes and words onto a user stack, but
is responsible for using the appropriate instructions when popping data from the specific
user stack. No hardware detection of overflow or underflow of a user stack is provided.
The following addressing modes allow implementation of user stacks:
[– Rw], Rb or [– Rw], Rw: Pre-decrement Indirect Addressing.
Used to push one byte or word onto a user stack. This mode is only available for MOV
instructions and can specify any GPR as the user stack pointer.
Rb, [Rw+] or Rw, [Rw+]: Post-increment Index Register Indirect Addressing.
Used to pop one byte or word from a user stack. This mode is available to most
instructions, but only GPRs R0-R3 can be specified as the user stack pointer.
Rb, [Rw+] or Rw, [Rw+]: Post-increment Indirect Addressing.
Used to pop one byte or word from a user stack. This mode is only available for MOV
instructions and can specify any GPR as the user stack pointer.
20.2 Register Banking
Register banking provides the user with an extremely fast method to switch user context.
A single machine cycle instruction saves the old bank and enters a new register bank.
Each register bank may assign up to 16 registers. Each register bank should be
allocated during coding based on the needs of each task. Once the internal memory has
been partitioned into a register bank space, internal stack space and a global internal
memory area, each bank pointer is then assigned. Thus, upon entry into a new task, the
appropriate bank pointer is used as the operand for the SCXT (switch context)
instruction. Upon exit from a task a simple POP instruction to the context pointer (CP)
restores the previous task's register bank.
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20.3 Procedure Call Entry and Exit
To support modular programming a procedure mechanism is provided to allow coding of
frequently used portions of code into subroutines. The CALL and RET instructions store
and restore the value of the instruction pointer (IP) on the system stack before and after
a subroutine is executed.
Procedures may be called conditionally with instructions CALLA or CALLI, or be called
unconditionally using instructions CALLR or CALLS.
Note: Any data pushed onto the system stack during execution of the subroutine must
be popped before the RET instruction is executed.
Passing Parameters on the System Stack
Parameters may be passed via the system stack through PUSH instructions before the
subroutine is called, and POP instructions during execution of the subroutine. Base plus
offset indirect addressing also permits access to parameters without popping these
parameters from the stack during execution of the subroutine. Indirect addressing
provides a mechanism of accessing data referenced by data pointers, which are passed
to the subroutine.
In addition, two instructions have been implemented to allow one parameter to be
passed on the system stack without additional software overhead.
The PCALL (push and call) instruction first pushes the 'reg' operand and the IP contents
onto the system stack and then passes control to the subroutine specified by the 'caddr'
operand.
When exiting from the subroutine, the RETP (return and pop) instruction first pops the IP
and then the 'reg' operand from the system stack and returns to the calling program.
Cross Segment Subroutine Calls
Calls to subroutines in different segments require the use of the CALLS (call inter-
segment subroutine) instruction. This instruction preserves both the CSP (code segment
pointer) and IP on the system stack.
Upon return from the subroutine, a RETS (return from inter-segment subroutine)
instruction must be used to restore both the CSP and IP. This ensures that the next
instruction after the CALLS instruction is fetched from the correct segment.
Note: It is possible to use CALLS within the same segment, but still two words of the
stack are used to store both the IP and CSP.
Providing Local Registers for Subroutines
For subroutines which require local storage, the following methods are provided:
C165H
System Programming
Data Sheet 442 2001-04-19
PRELIMINARY
- EXCERPT -
Alternate Bank of Registers: Upon entry into a subroutine, it is possible to specify a
new set of local registers by executing the SCXT (switch context) instruction. This
mechanism does not provide a method to recursively call a subroutine.
Saving and Restoring of Registers: To provide local registers, the contents of the
registers which are required for use by the subroutine can be pushed onto the stack and
the previous values be popped before returning to the calling routine. This is the most
common technique used today and it does provide a mechanism to support recursive
procedures. This method, however, requires two machine cycles per register stored on
the system stack (one cycle to PUSH the register, and one to POP the register).
Use of the System Stack for Local Registers: It is possible to use the SP and CP to
set up local subroutine register frames. This enables subroutines to dynamically allocate
local variables as needed within two machine cycles. A local frame is allocated by simply
subtracting the number of required local registers from the SP, and then moving the
value of the new SP to the CP.
This operation is supported through the SCXT (switch context) instruction with the
addressing mode 'reg, mem'. Using this instruction saves the old contents of the CP on
the system stack and moves the value of the SP into CP (see example below). Each local
register is then accessed as if it was a normal register. Upon exit from the subroutine,
first the old CP must be restored by popping it from the stack and then the number of
used local registers must be added to the SP to restore the allocated local space back
to the system stack.
Note: The system stack is growing downwards, while the register bank is growing
upwards.
Figure 139 Local Registers
Old Stack
Area
Newly
Allocated
Register
Bank
R4
R3
R2
R1
R0
Old CP Contents
Old SP
New SP
New CP
New
Stack
Area
C165H
System Programming
Data Sheet 443 2001-04-19
PRELIMINARY
- EXCERPT -
The software to provide the local register bank for the example above is very compact:
After entering the subroutine:
SUB SP, #10D ;Free 5 words in the current system stack
SCXT CP, SP ;Set the new register bank pointer
Before exiting the subroutine:
POP CP ;Restore the old register bank
ADD SP, #10D ;Release the 5 words...
;...of the current system stack
20.4 Table Searching
A number of features have been included to decrease the execution time required to
search tables. First, branch delays are eliminated by the branch target cache after the
first iteration of the loop. Second, in non-sequentially searched tables, the enhanced
performance of the ALU allows more complicated hash algorithms to be processed to
obtain better table distribution. For sequentially searched tables, the auto-increment
indirect addressing mode and the E (end of table) flag stored in the PSW decrease the
number of overhead instructions executed in the loop.
The two examples below illustrate searching ordered tables and non-ordered tables,
respectively:
MOV R0, #BASE ;Move table base into R0
LOOP:
CMP R1, [R0+] ;Compare target to table entry
JMPR cc_SGT, LOOP ;Test whether target has not been found
Note: The last entry in the table must be greater than the largest possible target.
MOV R0, #BASE ;Move table base into R0
LOOP:
CMP R1, [R0+] ;Compare target to table entry
JMPR cc_NET, LOOP ;Test whether target is not found AND..
;..the end of table has not been reached.
Note: The last entry in the table must be equal to the lowest signed integer (8000H).
C165H
System Programming
Data Sheet 444 2001-04-19
PRELIMINARY
- EXCERPT -
20.5 Peripheral Control and Interface
All communication between peripherals and the CPU is performed either by PEC
transfers to and from internal memory, or by explicitly addressing the SFRs associated
with the specific peripherals. After resetting the C165H all peripherals (except the
watchdog timer) are disabled and initialized to default values. A desired configuration of
a specific peripheral is programmed using MOV instructions of either constants or
memory values to specific SFRs. Specific control flags may also be altered via bit
instructions.
Once in operation, the peripheral operates autonomously until an end condition is
reached at which time it requests a PEC transfer or requests CPU servicing through an
interrupt routine. Information may also be polled from peripherals through read accesses
to SFRs or bit operations including branch tests on specific control bits in SFRs. To
ensure proper allocation of peripherals among multiple tasks, a portion of the internal
memory has been made bit addressable to allow user semaphores. Instructions have
also been provided to lock out tasks via software by setting or clearing user specific bits
and conditionally branching based on these specific bits.
It is recommended that bit fields in control SFRs are updated using the BFLDH and
BFLDL instructions or a MOV instruction to avoid undesired intermediate modes of
operation which can occur, when BCLR/BSET or AND/OR instruction sequences are
used.
20.6 Floating Point Support
All floating point operations are performed using software. Standard multiple precision
instructions are used to perform calculations on data types that exceed the size of the
ALU. Multiple bit rotate and logic instructions allow easy masking and extracting of
portions of floating point numbers.
To decrease the time required to perform floating point operations, two hardware
features have been implemented in the CPU core. First, the PRIOR instruction aids in
normalizing floating point numbers by indicating the position of the first set bit in a GPR.
This result can the be used to rotate the floating point result accordingly. The second
feature aids in properly rounding the result of normalized floating point numbers through
the overflow (V) flag in the PSW. This flag is set when a one is shifted out of the carry bit
during shift right operations. The overflow flag and the carry flag are then used to round
the floating point result based on the desired rounding algorithm.
20.7 Trap/Interrupt Entry and Exit
Interrupt routines are entered when a requesting interrupt has a priority higher than the
current CPU priority level. Traps are entered regardless of the current CPU priority.
When either a trap or interrupt routine is entered, the state of the machine is preserved
on the system stack and a branch to the appropriate trap/interrupt vector is made.
C165H
System Programming
Data Sheet 445 2001-04-19
PRELIMINARY
- EXCERPT -
All trap and interrupt routines require the use of the RETI (return from interrupt)
instruction to exit from the called routine. This instruction restores the system state from
the system stack and then branches back to the location where the trap or interrupt
occurred.
20.8 Unseparable Instruction Sequences
The instructions of the C165H are very efficient (most instructions execute in one
machine cycle) and even the multiplication and division are interruptable in order to
minimize the response latency to interrupt requests (internal and external). In many
microcontroller applications this is vital.
Some special occasions, however, require certain code sequences (eg. semaphore
handling) to be uninterruptable to function properly. This can be provided by inhibiting
interrupts during the respective code sequence by disabling and enabling them before
and after the sequence. The necessary overhead may be reduced by means of the
ATOMIC instruction which allows locking 1...4 instructions to an unseparable code
sequence, during which the interrupt system (standard interrupts and PEC requests)
and Class A Traps (NMI, stack overflow/underflow) are disabled. A Class B Trap
(illegal opcode, illegal bus access, etc.), however, will interrupt the atomic sequence,
since it indicates a severe hardware problem. The interrupt inhibit caused by an ATOMIC
instruction gets active immediately, ie. no other instruction will enter the pipeline except
the one that follows the ATOMIC instruction, and no interrupt request will be serviced in
between. All instructions requiring multiple cycles or hold states are regarded as one
instruction in this sense (eg. MUL is one instruction). Any instruction type can be used
within an unseparable code sequence.
ATOMIC #3 ;The next 3 instr. are locked (No NOP requ.)
MOV R0, #1234H ;Instr. 1 (no other instr. enters pipeline!)
MOV R1, #5678H ;Instr. 2
MUL R0, R1 ;Instr. 3: MUL regarded as one instruction
MOV R2, MDL ;This instruction is out of the scope...
;...of the ATOMIC instruction sequence
20.9 Overriding the DPP Addressing Mechanism
The standard mechanism to access data locations uses one of the four data page
pointers (DPPx), which selects a 16 KByte data page, and a 14-bit offset within this data
page. The four DPPs allow immediate access to up to 64 KByte of data. In applications
with big data arrays, especially in HLL applications using large memory models, this may
require frequent reloading of the DPPs, even for single accesses.
C165H
System Programming
Data Sheet 446 2001-04-19
PRELIMINARY
- EXCERPT -
The EXTP (extend page) instruction allows switching to an arbitrary data page for 1...4
instructions without having to change the current DPPs.
EXTP R15, #1 ;The override page number is stored in R15
MOV R0, [R14] ;The (14-bit) page offset is stored in R14
MOV R1, [R13] ;This instruction uses the std. DPP scheme!
The EXTS (extend segment) instruction allows switching to a 64 KByte segment
oriented data access scheme for 1...4 instructions without having to change the current
DPPs. In this case all 16 bits of the operand address are used as segment offset, with
the segment taken from the EXTS instruction. This greatly simplifies address calculation
with continuous data like huge arrays in “C”.
EXTS #15, #1 ;The override seg. is 15 (0F’0000H..0F’FFFFH)
MOV R0, [R14] ;The (16-bit) segment offset is stored in R14
MOV R1, [R13] ;This instruction uses the std. DPP scheme!
Note: Instructions EXTP and EXTS inhibit interrupts the same way as ATOMIC.
Short Addressing in the Extended SFR (ESFR) Space
The short addressing modes of the C165H (REG or BITOFF) implicitly access the SFR
space. The additional ESFR space would have to be accessed via long addressing
modes (MEM or [Rw]). The EXTR (extend register) instruction redirects accesses in
short addressing modes to the ESFR space for 1...4 instructions, so the additional
registers can be accessed this way, too.
The EXTPR and EXTSR instructions combine the DPP override mechanism with the
redirection to the ESFR space using a single instruction.
Note: Instructions EXTR, EXTPR and EXTSR inhibit interrupts the same way as
ATOMIC.
The switching to the ESFR area and data page overriding is checked by the
development tools or handled automatically.
Nested Locked Sequences
Each of the described extension instruction and the ATOMIC instruction starts an
internal “extension counter” counting the effected instructions. When another extension
or ATOMIC instruction is contained in the current locked sequence this counter is
restarted with the value of the new instruction. This allows the construction of locked
sequences longer than 4 instructions.
Note: • Interrupt latencies may be increased when using locked code sequences.
• PEC requests are not serviced during idle mode, if the IDLE instruction is part of
a locked sequence.
C165H
System Programming
Data Sheet 447 2001-04-19
PRELIMINARY
- EXCERPT -
Code Memory Configuration during Reset
The control input pin EA (External Access) enables the user to define the address area
from which the first instructions after reset are fetched. When EA is low (‘0’) during reset,
the internal code memory is disabled and the first instructions are fetched from external
memory. When EA is high (‘1’) during reset, the internal code memory is globally enabled
and the first instructions are fetched from the internal memory.
Enabling and Disabling the Internal Code Memory After Reset
If the internal code memory does not contain an appropriate startup code, the system
may be booted from external memory, while the internal memory is enabled afterwards
to provide access to library routines, tables, etc.
If the internal code memory only contains the startup code and/or test software, the
system may be booted from internal memory, which may then be disabled, after the
software has switched to executing from (eg.) external memory, in order to free the
address space occupied by the internal code memory, which is now unnecessary.
20.10 Pits, Traps and Mines
Although handling the internal code memory provides powerful means to enhance the
overall performance and flexibility of a system, extreme care must be taken in order to
avoid a system crash. Instruction memory is the most crucial resource for the C165H and
it must be made sure that it never runs out of it. The following precautions help to take
advantage of the methods mentioned above without jeopardizing system security.
General Rules
When mapping the code memory no instruction or data accesses should be made to the
internal memory, otherwise unpredictable results may occur.
To avoid these problems, the instructions that configure the internal code memory
should be executed from external memory or from the on-chip RAM.
Whenever the internal code memory is disabled, enabled or remapped the DPPs must
be explicitly (re)loaded to enable correct data accesses to the internal and/or external
memory.
C165H
Register Set
Data Sheet 448 2001-04-19
PRELIMINARY
- EXCERPT -
21 Register Set
This section summarizes all registers, which are implemented in the C165H and explains
the description format which is used in the chapters describing the function and layout of
the SFRs.
For easy reference the registers are ordered according to two different keys (except for
GPRs):
• Ordered by address, to check which register a given address references,
• Ordered by register name, to find the location of a specific register.
21.1 Register Description Format
In the respective chapters the function and the layout of the SFRs is described in a
specific format which provides a number of details about the described special function
register. The example below shows how to interpret these details.
A word register looks like this:
REG_NAME (A16H / A8H) E/SFR Reset Value: * * * *H
A byte register looks like this:
REG_NAME (A16H / A8H) E/SFR Reset Value: - - * *H
Elements:
REG_NAME Name of this register
A16 / A8 Long 16-bit address / Short 8-bit address
SFR/ESFR/XReg Register space (SFR, ESFR or External/XBUS Register)
(* *) * * Register contents after reset
0/1: defined value, ’X’: undefined, ’U’: unchanged (undefined (’X’) after power up)
Bits that are set/cleared by hardware are marked with a shaded access box
Bit Function
bit(field)name Explanation of bit(field)name
Description of the functions controlled by this bit(field).
54321011 10 987615 14 13 12
rw rw- w rw rrw rw----
res.res.res.res.res. write
only read
only bitfield bitfield
hw
bit std
bit hw
bit
54321011 10 987615 14 13 12
rw rw- - - - rw rw----
bitfieldbitfield
std
bit hw
bit
hwbit
C165H
Register Set
Data Sheet 449 2001-04-19
PRELIMINARY
- EXCERPT -
21.2 CPU General Purpose Registers (GPRs)
The GPRs form the register bank that the CPU works with. This register bank may be
located anywhere within the internal RAM via the Context Pointer (CP). Due to the
addressing mechanism, GPR banks can only reside within the internal RAM. All GPRs
are bit-addressable.
The first 8 GPRs (R7...R0) may also be accessed bytewise. Other than with SFRs,
writing to a GPR byte does not affect the other byte of the respective GPR.
The respective halves of the byte-accessible registers receive special names:
Name Physical
Address
8-Bit
Address
Description Reset
Value
R0 (CP) + 0 F0HCPU General Purpose (Word) Register R0 UUUUH
R1 (CP) + 2 F1HCPU General Purpose (Word) Register R1 UUUUH
R2 (CP) + 4 F2HCPU General Purpose (Word) Register R2 UUUUH
R3 (CP) + 6 F3HCPU General Purpose (Word) Register R3 UUUUH
R4 (CP) + 8 F4HCPU General Purpose (Word) Register R4 UUUUH
R5 (CP) + 10 F5HCPU General Purpose (Word) Register R5 UUUUH
R6 (CP) + 12 F6HCPU General Purpose (Word) Register R6 UUUUH
R7 (CP) + 14 F7HCPU General Purpose (Word) Register R7 UUUUH
R8 (CP) + 16 F8HCPU General Purpose (Word) Register R8 UUUUH
R9 (CP) + 18 F9HCPU General Purpose (Word) Register R9 UUUUH
R10 (CP) + 20 FAHCPU General Purpose (Word) Register R10 UUUUH
R11 (CP) + 22 FBHCPU General Purpose (Word) Register R11 UUUUH
R12 (CP) + 24 FCHCPU General Purpose (Word) Register R12 UUUUH
R13 (CP) + 26 FDHCPU General Purpose (Word) Register R13 UUUUH
R14 (CP) + 28 FEHCPU General Purpose (Word) Register R14 UUUUH
R15 (CP) + 30 FFHCPU General Purpose (Word) Register R15 UUUUH
Name Physical
Address
8-Bit
Address
Description Reset
Value
RL0 (CP) + 0 F0HCPU General Purpose (Byte) Register RL0 UUH
RH0 (CP) + 1 F1HCPU General Purpose (Byte) Register RH0 UUH
RL1 (CP) + 2 F2HCPU General Purpose (Byte) Register RL1 UUH
C165H
Register Set
Data Sheet 450 2001-04-19
PRELIMINARY
- EXCERPT -
21.3 Special Function Registers ordered by Address
The following table lists all SFRs which are implemented in the C165H ordered by physical address. Bit-
addressable SFRs are marked with the letter “b” in column “Type”.
SFRs within the Extended SFR-Space (ESFRs) are marked with the letter “E” in column “Type”.
Table 75 Registers ordered by Address
RH1 (CP) + 3 F3HCPU General Purpose (Byte) Register RH1 UUH
RL2 (CP) + 4 F4HCPU General Purpose (Byte) Register RL2 UUH
RH2 (CP) + 5 F5HCPU General Purpose (Byte) Register RH2 UUH
RL3 (CP) + 6 F6HCPU General Purpose (Byte) Register RL3 UUH
RH3 (CP) + 7 F7HCPU General Purpose (Byte) Register RH3 UUH
RL4 (CP) + 8 F8HCPU General Purpose (Byte) Register RL4 UUH
RH4 (CP) + 9 F9HCPU General Purpose (Byte) Register RH4 UUH
RL5 (CP) + 10 FAHCPU General Purpose (Byte) Register RL5 UUH
RH5 (CP) + 11 FBHCPU General Purpose (Byte) Register RH5 UUH
RL6 (CP) + 12 FCHCPU General Purpose (Byte) Register RL6 UUH
RH6 (CP) + 13 FDHCPU General Purpose (Byte) Register RH6 UUH
RL7 (CP) + 14 FEHCPU General Purpose (Byte) Register RL7 UUH
RH7 (CP) + 14 FFHCPU General Purpose (Byte) Register RH7 UUH
Physical
Addr
Register
Name
Type 8-bit
Addr
Description Reset
Value
R0 SFR-b F0HGeneral Purpose Register 0 UUUUH
R0 ESFR-b F0HGeneral Purpose Register 0 UUUUH
R1 SFR-b F1HGeneral Purpose Register 1 UUUUH
R1 ESFR-b F1HGeneral Purpose Register 1 UUUUH
R10 ESFR-b FAHGeneral Purpose Register 10 UUUUH
R10 SFR-b FAHGeneral Purpose Register 10 UUUUH
R11 SFR-b FBHGeneral Purpose Register 11 UUUUH
R11 ESFR-b FBHGeneral Purpose Register 11 UUUUH
R12 SFR-b FCHGeneral Purpose Register 12 UUUUH
R12 ESFR-b FCHGeneral Purpose Register 12 UUUUH
R13 SFR-b FDHGeneral Purpose Register 13 UUUUH
R13 ESFR-b FDHGeneral Purpose Register 13 UUUUH
R14 SFR-b FEHGeneral Purpose Register 14 UUUUH
Name Physical
Address
8-Bit
Address
Description Reset
Value
C165H
Register Set
Data Sheet 451 2001-04-19
PRELIMINARY
- EXCERPT -
R14 ESFR-b FEHGeneral Purpose Register 14 UUUUH
R15 ESFR-b FFHGeneral Purpose Register 15 UUUUH
R15 SFR-b FFHGeneral Purpose Register 15 UUUUH
R2 SFR-b F2HGeneral Purpose Register 2 UUUUH
R2 ESFR-b F2HGeneral Purpose Register 2 UUUUH
R3 SFR-b F3HGeneral Purpose Register 3 UUUUH
R3 ESFR-b F3HGeneral Purpose Register 3 UUUUH
R4 ESFR-b F4HGeneral Purpose Register 4 UUUUH
R4 SFR-b F4HGeneral Purpose Register 4 UUUUH
R5 ESFR-b F5HGeneral Purpose Register 5 UUUUH
R5 SFR-b F5HGeneral Purpose Register 5 UUUUH
R6 ESFR-b F6HGeneral Purpose Register 6 UUUUH
R6 SFR-b F6HGeneral Purpose Register 6 UUUUH
R7 ESFR-b F7HGeneral Purpose Register 7 UUUUH
R7 SFR-b F7HGeneral Purpose Register 7 UUUUH
R8 SFR-b F8HGeneral Purpose Register 8 UUUUH
R8 ESFR-b F8HGeneral Purpose Register 8 UUUUH
R9 SFR-b F9HGeneral Purpose Register 9 UUUUH
R9 ESFR-b F9HGeneral Purpose Register 9 UUUUH
F014HXADRS1 ESFR 0AHXBUS Address Select Register 1
F016HXADRS2 ESFR 0BHXBUS Address Select Register 2
F018HXADRS3 ESFR 0CHXBUS Address Select Register 3
F01AHXADRS4 ESFR 0DHXBUS Address Select Register 4
F01CHXADRS5 ESFR 0EHXBUS Address Select Register 5
F01EHXADRS6 ESFR 0FHXBUS Address Select Register 6
F024HXPERCON ESFR 12HXBUS Peripheral Control Register 0401H
F076HIDMEM2 ESFR 3BHIdentifier 0000H
F078HIDPROG ESFR 3CHIdentifier 0000H
F07AHIDMEM ESFR 3DHIdentifier 0000H
F07CHIDCHIP ESFR 3EHIdentifier 0503H
F07EHIDMANUF ESFR 3FHIdentifier 1824H
F0B0HSSCTB ESFR 58HSSC Transmit Buffer (WO) 0000H
F0B2HSSCRB ESFR 59HSSC Receive Buffer (RO) xxxxH
F0B4HSSCBR ESFR 5AHSSC Baudrate Register 0000H
F0B6HSSCCLC ESFR 5BHSSC Clock Control Register 0000H
Physical
Addr
Register
Name
Type 8-bit
Addr
Description Reset
Value
C165H
Register Set
Data Sheet 452 2001-04-19
PRELIMINARY
- EXCERPT -
F0C0HSCUSLC ESFR 60HSecurity Level Control Register 0000H
F0C2HSCUSLS ESFR 61HSecurity Level Status Register 0000H
F0C8HRTCCLC ESFR 64HRTC Clock Control Register 0000H
F0CCHRTCRELL ESFR 66HRTC Timer Reload Register Low 0000H
F0CEHRTCRELH ESFR 67HRTC Timer Reload Register High 0000H
F0D0HT14REL ESFR 68HTimer 14 Reload Register nH
F0D2HT14 ESFR 69HTimer 14 Register nH
F0D4HRTCL ESFR 6AHRTC Timer Register Low nH
F0D6HRTCH ESFR 6BHRTC Timer Register High nH
F0D8HDTIDR ESFR 6CHTask ID register1) 0000H
F100HDP0L ESFR-b 80HP0L Direction Control Register 00H
F102HDP0H ESFR-b 81HP0H Direction Control Register 00H
F104HDP1L ESFR-b 82HP1L Direction Control Register 00H
F106HDP1H ESFR-b 83HP1H Direction Control Register 00H
F108HRP0H ESFR-b 84HSystem Startup Configuration Register (RO) xxH
F114HXBCON1 ESFR-b 8AHXBUS Control register 1: IOM-2 module 0000H
F116HXBCON2 ESFR-b 8BHXBUS Control register 2: reserved 0000H
F118HXBCON3 ESFR-b 8CHXBUS Control register 3: reserved 0000H
F11AHXBCON4 ESFR-b 8DHXBUS Control register 4: reserved 0000H
F11CHXBCON5 ESFR-b 8EHXBUS Control register 5: reserved 0000H
F11EHXBCON6 ESFR-b 8FHXBUS Control register 6: reserved 0000H
F160HUTD3IC ESFR-b B0HUDC TX Done3 Interrupt Control Register 0000H
F162HUTD4IC ESFR-b B1HUDC TX Done4 Interrupt Control Register 0000H
F164HUTD5IC ESFR-b B2HUDC TX Done5 Interrupt Control Register 0000H
F166HUTD6IC ESFR-b B3HUDC TX Done6 Interrupt Control Register 0000H
F168HUTD7IC ESFR-b B4HUDC TX Done7 Interrupt Control Register 0000H
F16AHURXRIC ESFR-b B5HUDC RXRR Interrupt Control Register 0000H
F16CHUTXRIC ESFR-b B6HUDC TXWR Interrupt Control Register 0000H
F16EHUCFGVIC ESFR-b B7HUDC Config Val Interrupt Control Register 0000H
F170HUSOFIC ESFR-b B8HUDC Start of Frame Interrupt Control Register 0000H
F172HUSSOIC ESFR-b B9HUDC Suspend off Interrupt Control Register 0000H
F174HUSSIC ESFR-b BAHUDC Suspend Interrupt Control Register 0000H
F176HULCDIC ESFR-b BBHUDC Load Config Done Interrupt Control
Register
0000H
F178HUSETIC ESFR-b BCHUDC SETUP Interrupt Control Register 0000H
F17AHURD0IC ESFR-b BDHUDC RX Done0 Interrupt Control Register 0000H
Physical
Addr
Register
Name
Type 8-bit
Addr
Description Reset
Value
C165H
Register Set
Data Sheet 453 2001-04-19
PRELIMINARY
- EXCERPT -
F17EHIOMC0TIC ESFR-b BFHIOM-2 Channel0 TX Interrupt Control Register 0000H
F180HPECCLIC ESFR-b C0HPEC Channel Link Interrupt Control Register 0000H
F182HIOMC0RIC ESFR-b C1HIOM-2 Channel0 RX Interrupt Control Register 0000H
F184HRTC_INTIC ESFR-b C2HRTC_INT Sub Node Interrupt Register 0000H
F186HXP0IC ESFR-b C3HX-Bus Peripheral 0 UDC TXWR Interrupt Control
Register
0000H
F18AHIOMC1TIC ESFR-b C5HIOM-2 Channel1 TX Interrupt Control Register 0000H
F18CHABENDIC ESFR-b C6HASC Autobaud End Interrupt Control Register 0000H
F18EHXP1IC ESFR-b C7HX-Bus Peripheral 1 Register 0000H
F192HIOMC1RIC ESFR-b C9HIOM-2 Channel1 RX Interrupt Control Register 0000H
F194HABSTIC ESFR-b CAHASC Autobaud Start Interrupt Control Register 0000H
F196HXP2IC ESFR-b CBHX-Bus Peripheral 2 IOM-2 IO Interrupt Control
Register
0000H
F19AHRES6IC ESFR-b CDHreserved 0000H
F19CHS0TBIC ESFR-b CEHSerial Channel 0 Transmit Buffer IC Register 0000H
F19EHXP3IC ESFR-b CFHX-Bus Peripheral 3 PLL/RTC Interrupt Control
Register
0000H
F1C0HEXICON ESFR-b E0HExternal Interrupt Control Register 0000H
F1C2HODP2 ESFR-b E1HPort 2 Open Drain Control Register 0000H
F1C6HODP3 ESFR-b E3HPort 3 Open Drain Control Register 0000H
F1C8HRTCISNC ESFR-b E4HRTC Interrupt Sub Node Control Register 0000H
F1CAHODP4 ESFR-b E5HPort 4 Open Drain Control Register 00H
F1CCHRTCCON ESFR-b E6HRTC Control Register 00H
F1CEHODP6 ESFR-b E7HPort 6 Open Drain Control Register 00H
F1D0HSYSCON2 ESFR-b E8HSystem Configuration Register 2/Clock Control 0000H
F1D2HODP7 ESFR-b E9HPort 7 Open Drain Control Register 00H
F1D4HSYSCON3 ESFR-b EAHSystem Configuration Register 3/Periph.
Managem.
0000H
F1D6Hreserved ESFR-b EBHreserved - do not use 0000H
F1D8Hreserved ESFR-b ECHreserved - do not use 0000H
F1DAHEXISEL ESFR-b EDHExternal Interrupt Select Register 0000H
F1DCHSYSCON1 ESFR-b EEHSystem Configuration Register 1/Sleep Mode 0000H
F1DEHISNC ESFR-b EFHInterrupt Sub Node Control Register 0000H
FE00HDPP0 SFR 00HCPU Data Page Pointer 0 Register (10 bits) 0000H
FE02HDPP1 SFR 01HCPU Data Page Pointer 1 Register (10 bits) 0001H
FE04HDPP2 SFR 02HCPU Data Page Pointer 2 Register (10 bits) 0002H
FE06HDPP3 SFR 03HCPU Data Page Pointer 3 Register (10 bits) 0003H
Physical
Addr
Register
Name
Type 8-bit
Addr
Description Reset
Value
C165H
Register Set
Data Sheet 454 2001-04-19
PRELIMINARY
- EXCERPT -
FE08HCSP SFR 04HCPU Code Segment Pointer Register (8 bits) 0000H
FE0AHEMUCON SFR 05HEmulation Control Register2) xxxxH
FE0CHMDH SFR 06HCPU Multiply Divide Register - High Word 0000H
FE0EHMDL SFR 07HCPU Multiply Divide Register - Low Word 0000H
FE10HCP SFR 08HCPU Context Pointer Register FC00H
FE12HSP SFR 09HCPU System Stack Pointer Register FC00H
FE14HSTKOV SFR 0AHCPU Stack Overflow Pointer Register FA00H
FE16HSTKUN SFR 0BHCPU Stack Underflow Pointer Register FC00H
FE18HADDRSEL1 SFR 0CHAddress Select Register 1 0000H
FE1AHADDRSEL2 SFR 0DHAddress Select Register 2 0000H
FE1CHADDRSEL3 SFR 0EHAddress Select Register 3 0000H
FE1EHADDRSEL4 SFR 0FHAddress Select Register 4 0000H
FE22HODP0H SFR 11HPort 0 Open Drain Control Register High 0000H
FE24HODP1L SFR 12HPort 1 Open Drain Control Register Low 0000H
FE26HODP1H SFR 13HPort 1 Open Drain Control Register High 0000H
FE40HT2 SFR 20HGPT1 Timer 2 Register 0000H
FE42HT3 SFR 21HGPT1 Timer 3 Register 0000H
FE44HT4 SFR 22HGPT1 Timer 4 Register 0000H
FE46HT5 SFR 23HGPT2 Timer 5 Register 0000H
FE48HT6 SFR 24HGPT2 Timer 6 Register 0000H
FE4AHCAPREL SFR 25HGPT1/2 Capture / Reload Register 0000H
FE4CHGPTCLC SFR 26HGPT1/2 Clock Control Register 0000H
FE60HP0LPUDSEL SFR 30HPort 0 Low Pull-Up/Down Select Register xxFFH
FE62HP0HPUDSEL SFR 31HPort 0 High Pull-Up/Down Select Register xxFFH
FE64HP0LPUDEN SFR 32HPort 0 Low Pull Switch On/Off Register xxFF
FE66HP0HPUDEN SFR 33HPort 0 High Pull Switch On/Off Register xxFFH
FE68HP0LPHEN SFR 34HPort 0 Low Pin Hold Enable Register 0000H
FE6AHP0HPHEN SFR 35HPort 0 High Pin Hold Enable Register 0000H
FE6CHP1LPUDSEL SFR 36HPort 1 Low Pull-Up/Down Select Register 0000H
FE6EHP1HPUDSEL SFR 37HPort 1 High Pull-Up/Down Select Register 0000H
FE70HP1LPUDEN SFR 38HPort 1 Low Pull Switch On/Off Register 0000H
FE72HP1HPUDEN SFR 39HPort 1 High Pull Switch On/Off Register 0000H
FE74HP1LPHEN SFR 3AHPort 1 Low Pin Hold Enable Register 0000H
FE76HP1HPHEN SFR 3BHPort 1 High Pin Hold Enable Register 0000H
FE78HP2PUDSEL SFR 3CHPort 2 Pull-Up/Down Select Register 0000H
Physical
Addr
Register
Name
Type 8-bit
Addr
Description Reset
Value
C165H
Register Set
Data Sheet 455 2001-04-19
PRELIMINARY
- EXCERPT -
FE7AHP2PUDEN SFR 3DHPort 2 Pull Switch On/Off Register 0000H
FE7CHP2PHEN SFR 3EHPort 2 Pin Hold Enable Register 0000H
FE7EHP3PUDSEL SFR 3FHPort 3 Pull-Up/Down Select Register 0000H
FE80HP3PUDEN SFR 40HPort 3 Pull Switch On/Off Register 0000H
FE82HP3PHEN SFR 41HPort 3 Pin Hold Enable Register 0000H
FE84HP4PUDSEL SFR 42HPort 4 Pull-Up/Down Select Register 0000H
FE86HP4PUDEN SFR 43HPort 4 Pull Switch On/Off Register 0000H
FE88HP4PHEN SFR 44HPort 4 Pin Hold Enable Register 0000H
FE90HP6PUDSEL SFR 48HPort 6 Pull-Up/Down Select Register 0000H
FE92HP6PUDEN SFR 49HPort 6 Pull Switch On/Off Register 0000H
FE94HP6PHEN SFR 4AHPort 6 Pin Hold Enable Register 0000H
FE96HP7PUDSEL SFR 4BHPort 7 Pull-Up/Down Select Register 0000H
FE98HP7PUDEN SFR 4CHPort 7 Pull Switch On/Off Register 0000H
FE9AHP7PHEN SFR 4DHPort 7 Pin Hold Enable Register 0000H
FEAAHS0PMW SFR 55HASC IrDA PMW Control Register 0000H
FEAEHWDT SFR 57HWatchdog Timer Register (RO) 0000H
FEB0HS0TBUF SFR 58HSerial Channel 0 Transmit Buffer Register (WO) 0000H
FEB2HS0RBUF SFR 59HSerial Channel 0 Receive Buffer Register (RO) xxxxH
FEB4HS0BG SFR 5AHSerial Channel 0 Baud Rate Generator Reload
Register
0000H
FEB6HS0FDV SFR 5BHASC Fractional Divide Register 0000H
FEC0HPECC0 SFR 60HPEC Channel 0 Control Register 0000H
FEC2HPECC1 SFR 61HPEC Channel 1 Control Register 0000H
FEC4HPECC2 SFR 62HPEC Channel 2 Control Register 0000H
FEC6HPECC3 SFR 63HPEC Channel 3 Control Register 0000H
FEC8HPECC4 SFR 64HPEC Channel 4 Control Register 0000H
FECAHPECC5 SFR 65HPEC Channel 5 Control Register 0000H
FECCHPECC6 SFR 66HPEC Channel 6 Control Register 0000H
FECEHPECC7 SFR 67HPEC Channel 7 Control Register 0000H
FED0HPECSN0 SFR 68HPEC Segment No Register
FED2HPECSN1 SFR 69HPEC Segment No Register
FED4HPECSN2 SFR 6AHPEC Segment No Register
FED6HPECSN3 SFR 6BHPEC Segment No Register
FED8HPECSN4 SFR 6CHPEC Segment No Register
FEDAHPECSN5 SFR 6DHPEC Segment No Register
FEDCHPECSN6 SFR 6EHPEC Segment No Register
Physical
Addr
Register
Name
Type 8-bit
Addr
Description Reset
Value
C165H
Register Set
Data Sheet 456 2001-04-19
PRELIMINARY
- EXCERPT -
FEDEHPECSN7 SFR 6FHPEC Segment No Register
FEF0HPECXC0 SFR 78HPEC Channel 0 Extended Control Register
FEF2HPECXC2 SFR 79HPEC Channel 2 Extended Control Register
FEF8HABS0CON SFR 7CHASC Autobaud Control Register 0000H
FEFEHABSTAT SFR 7FHASC Autobaud Status Register 0000H
FF00HP0L SFR-b 80HPort 0 Low Register (Lower half) 00H
FF02HP0H SFR-b 81HPort 0 High Register (Upper half) 00H
FF04HP1L SFR-b 82HPort 1 Low Register (Lower half) 00H
FF06HP1H SFR-b 83HPort 1 High Register (Upper half) 00H
FF0CHBUSCON0 SFR-b 86HBus Configuration Register 0 0000H
FF0EHMDC SFR-b 87HCPU Multiply Divide Control Register 0000H
FF10HPSW SFR-b 88HCPU Program Status Word 0000H
FF12HSYSCON SFR-b 89HCPU System Configuration Register 0xx0H
FF14HBUSCON1 SFR-b 8AHBus Configuration Register 1 0000H
FF16HBUSCON2 SFR-b 8BHBus Configuration Register 2 0000H
FF18HBUSCON3 SFR-b 8CHBus Configuration Register 3 0000H
FF1AHBUSCON4 SFR-b 8DHBus Configuration Register 4 0000H
FF1CHZEROS SFR-b 8EHConstant Value 0sRegister' 0000H
FF1EHONES SFR-b 8FHConstant Value 1sRegister' FFFFH
FF40HT2CON SFR-b A0HGPT1 Timer 2 Control Register 0000H
FF42HT3CON SFR-b A1HGPT1 Timer 3 Control Register 0000H
FF44HT4CON SFR-b A2HGPT1 Timer 4 Control Register 0000H
FF46HT5CON SFR-b A3HGPT2 Timer 5 Control Register 0000H
FF48HT6CON SFR-b A4HGPT2 Timer 6 Control Register 0000H
FF60HT2IC SFR-b B0HGPT1 Timer 2 Interrupt Control Register 0000H
FF62HT3IC SFR-b B1HGPT1 Timer 3 Interrupt Control Register 0000H
FF64HT4IC SFR-b B2HGPT1 Timer 4 Interrupt Control Register 0000H
FF66HT5IC SFR-b B3HGPT2 Timer 5 Interrupt Control Register 0000H
FF68HT6IC SFR-b B4HGPT2 Timer 6 Interrupt Control Register 0000H
FF6AHCRIC SFR-b B5HGPT2 CAPREL Interrupt Control Register 0000H
FF6CHS0TIC SFR-b B6HSerial Channel 0 Transmit Interrupt Control
Register
0000H
FF6EHS0RIC SFR-b B7HSerial Channel 0 Receive Interrupt Control
Register
0000H
FF70HS0EIC SFR-b B8HSerial Channel 0 Error Interrupt Control Register 0000H
FF72HSSCTIC SFR-b B9HSSC Transmit Interrupt Control Register 0000H
Physical
Addr
Register
Name
Type 8-bit
Addr
Description Reset
Value
C165H
Register Set
Data Sheet 457 2001-04-19
PRELIMINARY
- EXCERPT -
FF74HSSCRIC SFR-b BAHSSC Receive Interrupt Control Register 0000H
FF76HSSCEIC SFR-b BBHSSC Error Interrupt Control Register 0000H
FF78HURD3IC SFR-b BCHUDC RX Done3 Interrupt Control Register 0000H
FF7AHURD4IC SFR-b BDHUDC RX Done4 Interrupt Control Register 0000H
FF7CHURD5IC SFR-b BEHUDC RX Done5 Interrupt Control Register 0000H
FF7EHURD6IC SFR-b BFHUDC RX Done6 Interrupt Control Register 0000H
FF80HURD7IC SFR-b C0HUDC RX Done7 Interrupt Control Register 0000H
FF82HUTD0IC SFR-b C1HUDC TX Done0 Interrupt Control Register 0000H
FF84HUTD1IC SFR-b C2HUDC TX Done1 Interrupt Control Register 0000H
FF86HUTD2IC SFR-b C3HUDC TX Done2 Interrupt Control Register 0000H
FF88HFEI0IC SFR-b C4HFast External Interrupt 0 Control Register 0000H
FF8AHFEI1IC SFR-b C5HFast External Interrupt 1 Control Register 0000H
FF8CHFEI2IC SFR-b C6HFast External Interrupt 2 Control Register 0000H
FF8EHFEI3IC SFR-b C7HFast External Interrupt 3 Control Register 0000H
FF90HFEI4IC SFR-b C8HFast External Interrupt 4 Control Register 0000H
FF92HFEI5IC SFR-b C9HFast External Interrupt 5 Control Register 0000H
FF94HFEI6IC SFR-b CAHFast External Interrupt 6 Control Register 0000H
FF96HFEI7IC SFR-b CBHFast External Interrupt 7 Control Register 0000H
FF98HRES4IC SFR-b CBHreserved 0000H
FF9AHIOMIOIC SFR-b CDHIOM-2 IO Interrupt Control Register 0000H
FF9CHURD2IC SFR-b CEHUDC RX Done2 Interrupt Control Register 0000H
FF9EHURD1IC SFR-b CFHUDC RX Done1 Interrupt Control Register 0000H
FFA8HCLISNC SFR-b D4HThe channel link interrupt subnode register 0000H
FFAAHFOCON SFR-b D5HFrequency Output Control Register 0000H
FFACHTFR SFR-b D6HTrap Flag Register 0000H
FFAEHWDTCON SFR-b D7HWatchdog Timer Control Register 000xH
FFB0HS0CON SFR-b D8HSerial Channel 0 Control Register 0000H
FFB2HSSCCON SFR-b D9HSSC Control Register 0000H
FFBAHS0CLC SFR-b DDHASC Clock Control Register 0000H
FFC0HP2 SFR-b E0HPort 2 Register 0000H
FFC2HDP2 SFR-b E1HPort 2 Direction Control Register 0000H
FFC4HP3 SFR-b E2HPort 3 Register 0000H
FFC6HDP3 SFR-b E3HPort 3 Direction Control Register 0000H
FFC8HP4 SFR-b E4HPort 4 Register (8 bits) 00H
FFCAHDP4 SFR-b E5HPort 4 Direction Control Register 00H
Physical
Addr
Register
Name
Type 8-bit
Addr
Description Reset
Value
C165H
Register Set
Data Sheet 458 2001-04-19
PRELIMINARY
- EXCERPT -
21.4 Special Function Registers ordered by Name
The following table lists all SFRs which are implemented in the C165H ordered by their name. Bit-
addressable SFRs are marked with the letter “b” in column “Type”.
SFRs within the Extended SFR-Space (ESFRs) are marked with the letter “E” in column “Type”.
Table 76 Registers ordered by Name
FFCCHP6 SFR-b E6HPort 6 Register (8 bits) 00H
FFCEHDP6 SFR-b E7HPort 6 Direction Control Register 00H
FFD0HP7 SFR-b E8HPort 7 Register (8 bits) 00H
FFD2HDP7 SFR-b E9HPort 7 Direction Control Register 00H
1) The DTIDR register is a data register which is used by advanced real time operating systems to store the task
ID of the active task. It is used for hardware trigger events in the OCDS.
2) The EMUCON register is a reserved test register and is not to be used by other software.
Register
Name
Phys.
Addr
Type 8-bit
Addr
Description Reset
Value
ABENDIC F18CHESFR-b C6HASC Autobaud End Interrupt Control Register 0000H
ABS0CON FEF8HSFR 7CHASC Autobaud Control Register 0000H
ABSTAT FEFEHSFR 7FHASC Autobaud Status Register 0000H
ABSTIC F194HESFR-b CAHASC Autobaud Start Interrupt Control Register 0000H
ADDRSEL1 FE18HSFR 0CHAddress Select Register 1 0000H
ADDRSEL2 FE1AHSFR 0DHAddress Select Register 2 0000H
ADDRSEL3 FE1CHSFR 0EHAddress Select Register 3 0000H
ADDRSEL4 FE1EHSFR 0FHAddress Select Register 4 0000H
BUSCON0 FF0CHSFR-b 86HBus Configuration Register 0 0000H
BUSCON1 FF14HSFR-b 8AHBus Configuration Register 1 0000H
BUSCON2 FF16HSFR-b 8BHBus Configuration Register 2 0000H
BUSCON3 FF18HSFR-b 8CHBus Configuration Register 3 0000H
BUSCON4 FF1AHSFR-b 8DHBus Configuration Register 4 0000H
CAPREL FE4AHSFR 25HGPT1/2 Capture / Reload Register 0000H
CLISNC FFA8HSFR-b D4HThe channel link interrupt subnode register 0000H
CP FE10HSFR 08HCPU Context Pointer Register FC00H
CRIC FF6AHSFR-b B5HGPT2 CAPREL Interrupt Control Register 0000H
CSP FE08HSFR 04HCPU Code Segment Pointer Register (8 bits) 0000H
DP0H F102HESFR-b 81HP0H Direction Control Register 00H
DP0L F100HESFR-b 80HP0L Direction Control Register 00H
Physical
Addr
Register
Name
Type 8-bit
Addr
Description Reset
Value
C165H
Register Set
Data Sheet 459 2001-04-19
PRELIMINARY
- EXCERPT -
DP1H F106HESFR-b 83HP1H Direction Control Register 00H
DP1L F104HESFR-b 82HP1L Direction Control Register 00H
DP2 FFC2HSFR-b E1HPort 2 Direction Control Register 0000H
DP3 FFC6HSFR-b E3HPort 3 Direction Control Register 0000H
DP4 FFCAHSFR-b E5HPort 4 Direction Control Register 00H
DP6 FFCEHSFR-b E7HPort 6 Direction Control Register 00H
DP7 FFD2HSFR-b E9HPort 7 Direction Control Register 00H
DPP0 FE00HSFR 00HCPU Data Page Pointer 0 Register (10 bits) 0000H
DPP1 FE02HSFR 01HCPU Data Page Pointer 1 Register (10 bits) 0001H
DPP2 FE04HSFR 02HCPU Data Page Pointer 2 Register (10 bits) 0002H
DPP3 FE06HSFR 03HCPU Data Page Pointer 3 Register (10 bits) 0003H
DTIDR F0D8HESFR 6CHTask ID register 0000H
EMUCON FE0AHSFR 05HEmulation Control Register xxxxH
EXICON F1C0HESFR-b E0HExternal Interrupt Control Register 0000H
EXISEL F1DAHESFR-b EDHExternal Interrupt Select Register 0000H
FEI0IC FF88HSFR-b C4HFast External Interrupt 0 Control Register 0000H
FEI1IC FF8AHSFR-b C5HFast External Interrupt 1 Control Register 0000H
FEI2IC FF8CHSFR-b C6HFast External Interrupt 2 Control Register 0000H
FEI3IC FF8EHSFR-b C7HFast External Interrupt 3 Control Register 0000H
FEI4IC FF90HSFR-b C8HFast External Interrupt 4 Control Register 0000H
FEI5IC FF92HSFR-b C9HFast External Interrupt 5 Control Register 0000H
FEI6IC FF94HSFR-b CAHFast External Interrupt 6 Control Register 0000H
FEI7IC FF96HSFR-b CBHFast External Interrupt 7 Control Register 0000H
FOCON FFAAHSFR-b D5HFrequency Output Control Register 0000H
GPTCLC FE4CHSFR 26HGPT1/2 Clock Control Register 0000H
IDCHIP F07CHESFR 3EHIdentifier 0503H
IDMANUF F07EHESFR 3FHIdentifier 1824H
IDMEM F07AHESFR 3DHIdentifier 0000H
IDMEM2 F076HESFR 3BHIdentifier 0000H
IDPROG F078HESFR 3CHIdentifier 0000H
IOMC0RIC F182HESFR-b C1HIOM-2 Channel0 RX Interrupt Control Register 0000H
IOMC0TIC F17EHESFR-b BFHIOM-2 Channel0 TX Interrupt Control Register 0000H
IOMC1RIC F192HESFR-b C9HIOM-2 Channel1 RX Interrupt Control Register 0000H
IOMC1TIC F18AHESFR-b C5HIOM-2 Channel1 TX Interrupt Control Register 0000H
IOMIOIC FF9AHSFR-b CDHIOM-2 IO Interrupt Control Register 0000H
Register
Name
Phys.
Addr
Type 8-bit
Addr
Description Reset
Value
C165H
Register Set
Data Sheet 460 2001-04-19
PRELIMINARY
- EXCERPT -
ISNC F1DEHESFR-b EFHInterrupt Sub Node Control Register 0000H
MDC FF0EHSFR-b 87HCPU Multiply Divide Control Register 0000H
MDH FE0CHSFR 06HCPU Multiply Divide Register - High Word 0000H
MDL FE0EHSFR 07HCPU Multiply Divide Register - Low Word 0000H
ODP0H FE22HSFR 11HPort 0 Open Drain Control Register High 0000H
ODP1H FE26HSFR 13HPort 1 Open Drain Control Register High 0000H
ODP1L FE24HSFR 12HPort 1 Open Drain Control Register Low 0000H
ODP2 F1C2HESFR-b E1HPort 2 Open Drain Control Register 0000H
ODP3 F1C6HESFR-b E3HPort 3 Open Drain Control Register 0000H
ODP4 F1CAHESFR-b E5HPort 4 Open Drain Control Register 00H
ODP6 F1CEHESFR-b E7HPort 6 Open Drain Control Register 00H
ODP7 F1D2HESFR-b E9HPort 7 Open Drain Control Register 00H
ONES FF1EHSFR-b 8FHConstant Value 1sRegister' FFFFH
P0H FF02HSFR-b 81HPort 0 High Register (Upper half) 00H
P0HPHEN FE6AHSFR 35HPort 0 High Pin Hold Enable Register 0000H
P0HPUDEN FE66HSFR 33HPort 0 High Pull Switch On/Off Register xxFFH
P0HPUDSEL FE62HSFR 31HPort 0 High Pull-Up/Down Select Register xxFFH
P0L FF00HSFR-b 80HPort 0 Low Register (Lower half) 00H
P0LPHEN FE68HSFR 34HPort 0 Low Pin Hold Enable Register 0000H
P0LPUDEN FE64HSFR 32HPort 0 Low Pull Switch On/Off Register xxFFH
P0LPUDSEL FE60HSFR 30HPort 0 Low Pull-Up/Down Select Register xxFFH
P1H FF06HSFR-b 83HPort 1 High Register (Upper half) 00H
P1HPHEN FE76HSFR 3BHPort 1 High Pin Hold Enable Register 0000H
P1HPUDEN FE72HSFR 39HPort 1 High Pull Switch On/Off Register 0000H
P1HPUDSEL FE6EHSFR 37HPort 1 High Pull-Up/Down Select Register 0000H
P1L FF04HSFR-b 82HPort 1 Low Register (Lower half) 00H
P1LPHEN FE74HSFR 3AHPort 1 Low Pin Hold Enable Register 0000H
P1LPUDEN FE70HSFR 38HPort 1 Low Pull Switch On/Off Register 0000H
P1LPUDSEL FE6CHSFR 36HPort 1 Low Pull-Up/Down Select Register 0000H
P2 FFC0HSFR-b E0HPort 2 Register 0000H
P2PHEN FE7CHSFR 3EHPort 2 Pin Hold Enable Register 0000H
P2PUDEN FE7AHSFR 3DHPort 2 Pull Switch On/Off Register 0000H
P2PUDSEL FE78HSFR 3CHPort 2 Pull-Up/Down Select Register 0000H
P3 FFC4HSFR-b E2HPort 3 Register 0000H
P3PHEN FE82HSFR 41HPort 3 Pin Hold Enable Register 0000H
Register
Name
Phys.
Addr
Type 8-bit
Addr
Description Reset
Value
C165H
Register Set
Data Sheet 461 2001-04-19
PRELIMINARY
- EXCERPT -
P3PUDEN FE80HSFR 40HPort 3 Pull Switch On/Off Register 0000H
P3PUDSEL FE7EHSFR 3FHPort 3 Pull-Up/Down Select Register 0000H
P4 FFC8HSFR-b E4HPort 4 Register (8 bits) 00H
P4PHEN FE88HSFR 44HPort 4 Pin Hold Enable Register 0000H
P4PUDEN FE86HSFR 43HPort 4 Pull Switch On/Off Register 0000H
P4PUDSEL FE84HSFR 42HPort 4 Pull-Up/Down Select Register 0000H
P6 FFCCHSFR-b E6HPort 6 Register (8 bits) 00H
P6PHEN FE94HSFR 4AHPort 6 Pin Hold Enable Register 0000H
P6PUDEN FE92HSFR 49HPort 6 Pull Switch On/Off Register 0000H
P6PUDSEL FE90HSFR 48HPort 6 Pull-Up/Down Select Register 0000H
P7 FFD0HSFR-b E8HPort 7 Register (8 bits) 00H
P7PHEN FE9AHSFR 4DHPort 7 Pin Hold Enable Register 0000H
P7PUDEN FE98HSFR 4CHPort 7 Pull Switch On/Off Register 0000H
P7PUDSEL FE96HSFR 4BHPort 7 Pull-Up/Down Select Register 0000H
PECC0 FEC0HSFR 60HPEC Channel 0 Control Register 0000H
PECC1 FEC2HSFR 61HPEC Channel 1 Control Register 0000H
PECC2 FEC4HSFR 62HPEC Channel 2 Control Register 0000H
PECC3 FEC6HSFR 63HPEC Channel 3 Control Register 0000H
PECC4 FEC8HSFR 64HPEC Channel 4 Control Register 0000H
PECC5 FECAHSFR 65HPEC Channel 5 Control Register 0000H
PECC6 FECCHSFR 66HPEC Channel 6 Control Register 0000H
PECC7 FECEHSFR 67HPEC Channel 7 Control Register 0000H
PECCLIC F180HESFR-b C0HPEC Channel Link Interrupt Control Register 0000H
PECSN0 FED0HSFR 68HPEC Segment No Register
PECSN1 FED2HSFR 69HPEC Segment No Register
PECSN2 FED4HSFR 6AHPEC Segment No Register
PECSN3 FED6HSFR 6BHPEC Segment No Register
PECSN4 FED8HSFR 6CHPEC Segment No Register
PECSN5 FEDAHSFR 6DHPEC Segment No Register
PECSN6 FEDCHSFR 6EHPEC Segment No Register
PECSN7 FEDEHSFR 6FHPEC Segment No Register
PECXC0 FEF0HSFR 78HPEC Channel 0 Extended Control Register
PECXC2 FEF2HSFR 79HPEC Channel 2 Extended Control Register
PSW FF10HSFR-b 88HCPU Program Status Word 0000H
R0 SFR-b F0HGeneral Purpose Register 0 UUUUH
Register
Name
Phys.
Addr
Type 8-bit
Addr
Description Reset
Value
C165H
Register Set
Data Sheet 462 2001-04-19
PRELIMINARY
- EXCERPT -
R0 ESFR-b F0HGeneral Purpose Register 0 UUUUH
R1 SFR-b F1HGeneral Purpose Register 1 UUUUH
R1 ESFR-b F1HGeneral Purpose Register 1 UUUUH
R10 ESFR-b FAHGeneral Purpose Register 10 UUUUH
R10 SFR-b FAHGeneral Purpose Register 10 UUUUH
R11 SFR-b FBHGeneral Purpose Register 11 UUUUH
R11 ESFR-b FBHGeneral Purpose Register 11 UUUUH
R12 SFR-b FCHGeneral Purpose Register 12 UUUUH
R12 ESFR-b FCHGeneral Purpose Register 12 UUUUH
R13 SFR-b FDHGeneral Purpose Register 13 UUUUH
R13 ESFR-b FDHGeneral Purpose Register 13 UUUUH
R14 SFR-b FEHGeneral Purpose Register 14 UUUUH
R14 ESFR-b FEHGeneral Purpose Register 14 UUUUH
R15 ESFR-b FFHGeneral Purpose Register 15 UUUUH
R15 SFR-b FFHGeneral Purpose Register 15 UUUUH
R2 SFR-b F2HGeneral Purpose Register 2 UUUUH
R2 ESFR-b F2HGeneral Purpose Register 2 UUUUH
R3 SFR-b F3HGeneral Purpose Register 3 UUUUH
R3 ESFR-b F3HGeneral Purpose Register 3 UUUUH
R4 ESFR-b F4HGeneral Purpose Register 4 UUUUH
R4 SFR-b F4HGeneral Purpose Register 4 UUUUH
R5 ESFR-b F5HGeneral Purpose Register 5 UUUUH
R5 SFR-b F5HGeneral Purpose Register 5 UUUUH
R6 ESFR-b F6HGeneral Purpose Register 6 UUUUH
R6 SFR-b F6HGeneral Purpose Register 6 UUUUH
R7 ESFR-b F7HGeneral Purpose Register 7 UUUUH
R7 SFR-b F7HGeneral Purpose Register 7 UUUUH
R8 SFR-b F8HGeneral Purpose Register 8 UUUUH
R8 ESFR-b F8HGeneral Purpose Register 8 UUUUH
R9 SFR-b F9HGeneral Purpose Register 9 UUUUH
R9 ESFR-b F9HGeneral Purpose Register 9 UUUUH
RES4IC FF98HSFR-b CBHreserved 0000H
RES6IC F19AHESFR-b CDHreserved 0000H
reserved F1D6HESFR-b EBHreserved - do not use 0000H
reserved F1D8HESFR-b ECHreserved - do not use 0000H
Register
Name
Phys.
Addr
Type 8-bit
Addr
Description Reset
Value
C165H
Register Set
Data Sheet 463 2001-04-19
PRELIMINARY
- EXCERPT -
RP0H F108HESFR-b 84HSystem Startup Configuration Register (RO) xxH
RTC_INTIC F184HESFR-b C2HRTC_INT Sub Node Interrupt Register 0000H
RTCCLC F0C8HESFR 64HRTC Clock Control Register 0000H
RTCCON F1CCHESFR-b E6HRTC Control Register 00H
RTCH F0D6HESFR 6BHRTC Timer Register High nH
RTCISNC F1C8HESFR-b E4HRTC Interrupt Sub Node Control Register 0000H
RTCL F0D4HESFR 6AHRTC Timer Register Low nH
RTCRELH F0CEHESFR 67HRTC Timer Reload Register High 0000H
RTCRELL F0CCHESFR 66HRTC Timer Reload Register Low 0000H
S0BG FEB4HSFR 5AHSerial Channel 0 Baud Rate Generator Reload
Register
0000H
S0CLC FFBAHSFR-b DDHASC Clock Control Register 0000H
S0CON FFB0HSFR-b D8HSerial Channel 0 Control Register 0000H
S0EIC FF70HSFR-b B8HSerial Channel 0 Error Interrupt Control Register 0000H
S0FDV FEB6HSFR 5BHASC Fractional Divide Register 0000H
S0PMW FEAAHSFR 55HASC IrDA PMW Control Register 0000H
S0RBUF FEB2HSFR 59HSerial Channel 0 Receive Buffer Register (RO) xxxxH
S0RIC FF6EHSFR-b B7HSerial Channel 0 Receive Interrupt Control
Register
0000H
S0TBIC F19CHESFR-b CEHSerial Channel 0 Transmit Buffer IC Register 0000H
S0TBUF FEB0HSFR 58HSerial Channel 0 Transmit Buffer Register (WO) 0000H
S0TIC FF6CHSFR-b B6HSerial Channel 0 Transmit Interrupt Control
Register
0000H
SCUSLC F0C0HESFR 60HSecurity Level Control Register
SCUSLS F0C2HESFR 61HSecurity Level Status Register
SP FE12HSFR 09HCPU System Stack Pointer Register FC00H
SSCBR F0B4HESFR 5AHSSC Baudrate Register 0000H
SSCCLC F0B6HESFR 5BHSSC Clock Control Register 0000H
SSCCON FFB2HSFR-b D9HSSC Control Register 0000H
SSCEIC FF76HSFR-b BBHSSC Error Interrupt Control Register 0000H
SSCRB F0B2HESFR 59HSSC Receive Buffer (RO) xxxxH
SSCRIC FF74HSFR-b BAHSSC Receive Interrupt Control Register 0000H
SSCTB F0B0HESFR 58HSSC Transmit Buffer (WO) 0000H
SSCTIC FF72HSFR-b B9HSSC Transmit Interrupt Control Register 0000H
STKOV FE14HSFR 0AHCPU Stack Overflow Pointer Register FA00H
STKUN FE16HSFR 0BHCPU Stack Underflow Pointer Register FC00H
Register
Name
Phys.
Addr
Type 8-bit
Addr
Description Reset
Value
C165H
Register Set
Data Sheet 464 2001-04-19
PRELIMINARY
- EXCERPT -
SYSCON FF12HSFR-b 89HCPU System Configuration Register 0xx0H
SYSCON1 F1DCHESFR-b EEHSystem Configuration Register 1/Sleep Mode 0000H
SYSCON2 F1D0HESFR-b E8HSystem Configuration Register 2/Clock Control 0000H
SYSCON3 F1D4HESFR-b EAHSystem Configuration Register 3/Periph.
Managem.
0000H
T14 F0D2HESFR 69HTimer 14 Register nH
T14REL F0D0HESFR 68HTimer 14 Reload Register nH
T2 FE40HSFR 20HGPT1 Timer 2 Register 0000H
T2CON FF40HSFR-b A0HGPT1 Timer 2 Control Register 0000H
T2IC FF60HSFR-b B0HGPT1 Timer 2 Interrupt Control Register 0000H
T3 FE42HSFR 21HGPT1 Timer 3 Register 0000H
T3CON FF42HSFR-b A1HGPT1 Timer 3 Control Register 0000H
T3IC FF62HSFR-b B1HGPT1 Timer 3 Interrupt Control Register 0000H
T4 FE44HSFR 22HGPT1 Timer 4 Register 0000H
T4CON FF44HSFR-b A2HGPT1 Timer 4 Control Register 0000H
T4IC FF64HSFR-b B2HGPT1 Timer 4 Interrupt Control Register 0000H
T5 FE46HSFR 23HGPT2 Timer 5 Register 0000H
T5CON FF46HSFR-b A3HGPT2 Timer 5 Control Register 0000H
T5IC FF66HSFR-b B3HGPT2 Timer 5 Interrupt Control Register 0000H
T6 FE48HSFR 24HGPT2 Timer 6 Register 0000H
T6CON FF48HSFR-b A4HGPT2 Timer 6 Control Register 0000H
T6IC FF68HSFR-b B4HGPT2 Timer 6 Interrupt Control Register 0000H
TFR FFACHSFR-b D6HTrap Flag Register 0000H
UCFGVIC F16EHESFR-b B7HUDC Config Val Interrupt Control Register 0000H
ULCDIC F176HESFR-b BBHUDC Load Config Done Interrupt Control
Register
0000H
URD0IC F17AHESFR-b BDHUDC RX Done0 Interrupt Control Register 0000H
URD1IC FF9EHSFR-b CFHUDC RX Done1 Interrupt Control Register 0000H
URD2IC FF9CHSFR-b CEHUDC RX Done2 Interrupt Control Register 0000H
URD3IC FF78HSFR-b BCHUDC RX Done3 Interrupt Control Register 0000H
URD4IC FF7AHSFR-b BDHUDC RX Done4 Interrupt Control Register 0000H
URD5IC FF7CHSFR-b BEHUDC RX Done5 Interrupt Control Register 0000H
URD6IC FF7EHSFR-b BFHUDC RX Done6 Interrupt Control Register 0000H
URD7IC FF80HSFR-b C0HUDC RX Done7 Interrupt Control Register 0000H
URXRIC F16AHESFR-b B5HUDC RXRR Interrupt Control Register 0000H
USETIC F178HESFR-b BCHUDC SETUP Interrupt Control Register 0000H
Register
Name
Phys.
Addr
Type 8-bit
Addr
Description Reset
Value
C165H
Register Set
Data Sheet 465 2001-04-19
PRELIMINARY
- EXCERPT -
USOFIC F170HESFR-b B8HUDC Start of Frame Interrupt Control Register 0000H
USSIC F174HESFR-b BAHUDC Suspend Interrupt Control Register 0000H
USSOIC F172HESFR-b B9HUDC Suspend off Interrupt Control Register 0000H
UTD0IC FF82HSFR-b C1HUDC TX Done0 Interrupt Control Register 0000H
UTD1IC FF84HSFR-b C2HUDC TX Done1 Interrupt Control Register 0000H
UTD2IC FF86HSFR-b C3HUDC TX Done2 Interrupt Control Register 0000H
UTD3IC F160HESFR-b B0HUDC TX Done3 Interrupt Control Register 0000H
UTD4IC F162HESFR-b B1HUDC TX Done4 Interrupt Control Register 0000H
UTD5IC F164HESFR-b B2HUDC TX Done5 Interrupt Control Register 0000H
UTD6IC F166HESFR-b B3HUDC TX Done6 Interrupt Control Register 0000H
UTD7IC F168HESFR-b B4HUDC TX Done7 Interrupt Control Register 0000H
UTXRIC F16CHESFR-b B6HUDC TXWR Interrupt Control Register 0000H
WDT FEAEHSFR 57HWatchdog Timer Register (RO) 0000H
WDTCON FFAEHSFR-b D7HWatchdog Timer Control Register 000xH
XADRS1 F014HESFR 0AHXBUS Address Select Register 1
XADRS2 F016HESFR 0BHXBUS Address Select Register 2
XADRS3 F018HESFR 0CHXBUS Address Select Register 3
XADRS4 F01AHESFR 0DHXBUS Address Select Register 4
XADRS5 F01CHESFR 0EHXBUS Address Select Register 5
XADRS6 F01EHESFR 0FHXBUS Address Select Register 6
XBCON1 F114HESFR-b 8AHXBUS Control register 1: IOM-2 module 0000H
XBCON2 F116HESFR-b 8BHXBUS Control register 2: reserved 0000H
XBCON3 F118HESFR-b 8CHXBUS Control register 3: reserved 0000H
XBCON4 F11AHESFR-b 8DHXBUS Control register 4: reserved 0000H
XBCON5 F11CHESFR-b 8EHXBUS Control register 5: reserved 0000H
XBCON6 F11EHESFR-b 8FHXBUS Control register 6: reserved
XP0IC F186HESFR-b C3HX-Bus Peripheral 0 UDC TXWR Interrupt Control
Register
0000H
XP1IC F18EHESFR-b C7HX-Bus Peripheral 1 Register 0000H
XP2IC F196HESFR-b CBHX-Bus Peripheral 2 IOM-2 IO Interrupt Control
Register
0000H
XP3IC F19EHESFR-b CFHX-Bus Peripheral 3 PLL/RTC Interrupt Control
Register
0000H
XPERCON F024HESFR 12HXBUS Peripheral Control Register 0401H
ZEROS FF1CHSFR-b 8EHConstant Value 0sRegister' 0000H
Register
Name
Phys.
Addr
Type 8-bit
Addr
Description Reset
Value
C165H
Register Set
Data Sheet 466 2001-04-19
PRELIMINARY
- EXCERPT -
21.5 Special Notes
PEC Pointer Registers
The source and destination pointers for the peripheral event controller are mapped to a
special area within the internal RAM. Pointers that are not occupied by the PEC may
therefore be used like normal RAM. During Power Down mode or any warm reset the
PEC pointers are preserved.
The PEC and its registers are described in chapter “Interrupt and Trap Functions”.
GPR Access in the ESFR Area
The locations 00’F000H...00’F01EH within the ESFR area are reserved and allow to
access the current register bank via short register addressing modes. The GPRs are
mirrored to the ESFR area which allows access to the current register bank even after
switching register spaces (see example below).
MOV R5, DP3 ;GPR access via SFR area
EXTR #1
MOV R5, ODP3 ;GPR access via ESFR area
Writing Bytes to SFRs
All special function registers may be accessed wordwise or bytewise (some of them even
bitwise). Reading bytes from word SFRs is a non-critical operation. However, when
writing bytes to word SFRs the complementary byte of the respective SFR is cleared with
the write operation.
C165H
Instruction Set Summary
Data Sheet 467 2001-04-19
PRELIMINARY
- EXCERPT -
22 Instruction Set Summary
This chapter briefly summarizes the C165H's instructions ordered by instruction classes.
This provides a basic understanding of the C165H’s instruction set, the power and
versatility of the instructions and their general usage.
A detailed description of each single instruction, including its operand data type,
condition flag settings, addressing modes, length (number of bytes) and object code
format is provided in the “Instruction Set Manual” for the C16x Family. This manual
also provides tables ordering the instructions according to various criteria, to allow quick
references.
Summary of Instruction Classes
Grouping the various instruction into classes aids in identifying similar instructions (eg.
SHR, ROR) and variations of certain instructions (eg. ADD, ADDB). This provides an
easy access to the possibilities and the power of the instructions of the C165H.
Note: The used mnemonics refer to the detailled description.
Arithmetic Instructions
• Addition of two words or bytes: ADD ADDB
• Addition with Carry of two words or bytes: ADDC ADDCB
• Subtraction of two words or bytes: SUB SUBB
• Subtraction with Carry of two words or bytes: SUBC SUBCB
•16
*16 bit signed or unsigned multiplication: MUL MULU
• 16/16 bit signed or unsigned division: DIV DIVU
• 32/16 bit signed or unsigned division: DIVL DIVLU
• 1's complement of a word or byte: CPL CPLB
• 2's complement (negation) of a word or byte: NEG NEGB
Logical Instructions
• Bitwise ANDing of two words or bytes: AND ANDB
• Bitwise ORing of two words or bytes: OR ORB
• Bitwise XORing of two words or bytes: XOR XORB
Compare and Loop Control Instructions
• Comparison of two words or bytes: CMP CMPB
• Comparison of two words with post-increment
by either 1 or 2: CMPI1 CMPI2
• Comparison of two words with post-decrement
by either 1 or 2: CMPD1 CMPD2
C165H
Instruction Set Summary
Data Sheet 468 2001-04-19
PRELIMINARY
- EXCERPT -
Boolean Bit Manipulation Instructions
• Manipulation of a maskable bit field
in either the high or the low byte of a word: BFLDH BFLDL
• Setting a single bit (to ‘1’): BSET
• Clearing a single bit (to ‘0’): BCLR
• Movement of a single bit: BMOV
• Movement of a negated bit: BMOVN
• ANDing of two bits: BAND
• ORing of two bits: BOR
• XORing of two bits: BXOR
• Comparison of two bits: BCMP
Shift and Rotate Instructions
• Shifting right of a word: SHR
• Shifting left of a word: SHL
• Rotating right of a word: ROR
• Rotating left of a word: ROL
• Arithmetic shifting right of a word (sign bit shifting): ASHR
Prioritize Instruction
• Determination of the number of shift cycles required
to normalize a word operand (floating point support): PRIOR
Data Movement Instructions
• Standard data movement of a word or byte: MOV MOVB
• Data movement of a byte to a word location
with either sign or zero byte extension: MOVBS MOVBZ
Note: The data movement instructions can be used with a big number of different
addressing modes including indirect addressing and automatic pointer in-/
decrementing.
System Stack Instructions
• Pushing of a word onto the system stack: PUSH
• Popping of a word from the system stack: POP
• Saving of a word on the system stack,
and then updating the old word with a new value
(provided for register bank switching): SCXT
C165H
Instruction Set Summary
Data Sheet 469 2001-04-19
PRELIMINARY
- EXCERPT -
Jump Instructions
• Conditional jumping to an either absolutely,
indirectly, or relatively addressed target instruction
within the current code segment: JMPA JMPI JMPR
• Unconditional jumping to an absolutely addressed
target instruction within any code segment: JMPS
• Conditional jumping to a relatively addressed
target instruction within the current code segment
depending on the state of a selectable bit: JB JNB
• Conditional jumping to a relatively addressed
target instruction within the current code segment
depending on the state of a selectable bit
with a post-inversion of the tested bit
in case of jump taken (semaphore support): JBC JNBS
Call Instructions
• Conditional calling of an either absolutely
or indirectly addressed subroutine within
the current code segment: CALLA CALLI
• Unconditional calling of a relatively addressed
subroutine within the current code segment: CALLR
• Unconditional calling of an absolutely addressed
subroutine within any code segment: CALLS
• Unconditional calling of an absolutely addressed
subroutine within the current code segment plus
an additional pushing of a selectable register onto
the system stack: PCALL
• Unconditional branching to the interrupt or
trap vector jump table in code segment 0: TRAP
Return Instructions
• Returning from a subroutine
within the current code segment: RET
• Returning from a subroutine
within any code segment: RETS
• Returning from a subroutine within the current
code segment plus an additional popping of a
selectable register from the system stack: RETP
• Returning from an interrupt service routine: RETI
C165H
Instruction Set Summary
Data Sheet 470 2001-04-19
PRELIMINARY
- EXCERPT -
System Control Instructions
• Resetting the C165H via software: SRST
• Entering the Idle mode: IDLE
• Entering the Power Down mode: PWRDN
• Servicing the Watchdog Timer: SRVWDT
• Disabling the Watchdog Timer: DISWDT
• Signifying the end of the initialization routine
(pulls pin RSTOUT high, and disables the effect of
any later execution of a DISWDT instruction): EINIT
Miscellaneous
• Null operation which requires 2 bytes of
storage and the minimum time for execution: NOP
• Definition of an unseparable instruction sequence: ATOMIC
• Switch ‘reg’, ‘bitoff’ and ‘bitaddr’ addressing modes
to the Extended SFR space: EXTR
• Override the DPP addressing scheme
using a specific data page instead of the DPPs,
and optionally switch to ESFR space: EXTP EXTPR
• Override the DPP addressing scheme
using a specific segment instead of the DPPs,
and optionally switch to ESFR space: EXTS EXTSR
Note: The ATOMIC and EXT* instructions provide support for uninterruptable code
sequences eg. for semaphore operations. They also support data addressing
beyond the limits of the current DPPs (except ATOMIC), which is advantageous
for bigger memory models in high level languages. Refer to chapter “System
Programming” for examples.
Protected Instructions
Some instructions of the C165H which are critical for the functionality of the controller
are implemented as so-called Protected Instructions. These protected instructions use
the maximum instruction format of 32 bits for decoding, while the regular instructions
only use a part of it (eg. the lower 8 bits) with the other bits providing additional
information like involved registers. Decoding all 32 bits of a protected doubleword
instruction increases the security in cases of data distortion during instruction fetching.
Critical operations like a software reset are therefore only executed if the complete
instruction is decoded without an error. This enhances the safety and reliability of a
microcontroller system.
C165H
AC/DC Characteristics
Data Sheet 471 2001-04-19
PRELIMINARY
- EXCERPT -
23 AC/DC Characteristics
23.1 Absolute Maximum Ratings
• Storage temperature (TST) -65 to +150 °C
• Voltage on VDD pins with respect to ground (VSS) -0.5 to + 4.0 V
• Voltage on any pin with respect to ground (VSS) (except VDD, VSS, XTAL pins) -0.5 to
5.5 V
• Absolute maximum total I/O current 250 mA
• Absolute maximum current on any pin, sink or source 10 mA
Stresses beyond those listed above may cause permanent damage to the device. This
is a stress rating only, and functional operation of the C165H is not implied at these or
any other conditions above those indicated in the operational sections of this
specification. Exposure to absolute maximum rating conditions for extended periods
may affect device reliability.
23.2 Recommended Operating Conditions
The following conditions are to be met for correct operation of the device.
• Ambient temperature under bias (TA): -40 to +85 °C
• Load capacitance (CL): <100 pF
23.3 DC Characteristics
The parameters listed below partly represent the characteristics of the C165H and partly
its demands on the system. To aid in interpreting the table correctly when evaluating
parameters for a design, the following notation is used in the column “Symbol”:
CC (Controller Characteristics):
The logic of the C165H will provide signals with the respective timing characteristics.
SR (System Requirement):
The external system must provide signals with the respective timing characteristics to
the C165H.
C165H
AC/DC Characteristics
Data Sheet 472 2001-04-19
PRELIMINARY
- EXCERPT -
VDD = 3.3 V ± 10%;VSS = 0 V
TA = -40 to 85o C, nom = 25o C
1) Not tested; guaranteed by design characterization.
2) The maximum current may be drawn while the respective signal line remains inactive.
3) The minimum current must be drawn in order to drive the respective signal line active.
Table 77 DC Characteristics
Parameter Symbol Values Unit Test Condition
min nom max
Power source current,
normal operation
ICC – 100 150 mA 36 MHz system
frequency 6)
Power source current,
idle mode
IID – – t.b.d. mA –
Power source current,
sleep mode
IPD – 140 – µA–
Power source current,
power-down mode
IPD –25– µA–
Input low voltage VILSR -0.5 – 0.8 V –
Input high voltage
VIHSR 2.2 –
5.5
V V
DD= 3.6 V
VIHSR 2.0 – V VDD= 3.3 V
VIHSR 1.8 – V VDD= 3.0 V
Output low voltage VOLCC ––0.4 VIOL = 3.2 mA
Output high voltage VOHCC 2.4 – – V IOH = -3.2 mA
Input leakage current IOZ2CC ––±1µA0 V < VIN < VDD
RSTIN pullup resistor RRSTCC 100 – 660 kΩat VDD = 3.3 V
Read/Write inactive current 4) IRWH 2) ––-40 µAVOUT = 2.4 V
Read/Write active current 4) IRWL 3) -100 – – µAVOUT = VOLmax
ALE inactive current 4) IALEL 2) ––40 µAVOUT = VOLmax
ALE active current 4) IALEH 3) 100 – – µAVOUT = 2.4 V
Port 6 inactive current 4) IP6H 2) ––-40 µAVOUT = 2.4 V
Port 6 active current 4) IP6L 3) -100 – – µAVOUT = VOLmax
Port 0 configuration current 4) IP0H 2) ––-10 µAVIN = VIHmin
IP0L 3) -100 – – µAVIN = VILmax
XTAL1 input current IILCC ––±20 µA0 V < VIN < VDD
XTAL1 max input voltage5) VIH2 1–VDD + 0.3 V –
Pin capacitance 1)
(digital inputs/outputs)
CIOCC ––9 pFf = 1 MHz; TA =
25 °C
C165H
AC/DC Characteristics
Data Sheet 473 2001-04-19
PRELIMINARY
- EXCERPT -
4) This specification is only valid during Reset or during Adapt-mode. Port 6 pins are affected only if they are used
for CS output and the open drain function is not enabled.
5) Not 5-V tolerant.
6) At a lower system frequency, the power consumption decreases accordingly.
Note: The sum of power from all port pins may not exceed 1 W; total I/O current may not
exceed 250 mA.
Note: The strength of output drivers (IOL and IOH) is 7.5 mA.
23.4 Failsafe operation
C165H I/O pins may be exposed up to a 5.5 V level generated by the other system
components. That may happen during operation in the normal power range as well as
during power-up/down transitions when the value of VDD may be anywhere in the range
from 0 V to 3.63 V. The following table specifies 5.5 V failsafe conditions for the different
ranges of VDD.
Table 78 Failsafe conditions
VDD I/O Status Safe condition with
5.5 V applied to I/O pin
Note
Power-up Not
connected
Undetermined Not to exceed 10 mA on
any pin, 250 mA total _
0 V - 2.97
V
Undetermined Not to exceed 10 mA on
any pin, 250 mA total _
Normal
Power
range
2.97 V -
3.63 V
Determined Not to exceed 10 mA on
any pin, 250 mA total _
Power-
down
2.97 V -
2.25 V
Determined Not to exceed 10 mA on
any pin, 250 mA total
At 2.5 V ± 10% (Power
down mode) I/Os are
active and preserve the
status
2.25 V - 0 Undetermined Not to exceed 10 mA on
any pin, 250 mA total _
C165H
AC/DC Characteristics
Data Sheet 474 2001-04-19
PRELIMINARY
- EXCERPT -
23.5 Testing Waveforms
Figure 140 Input Output Waveforms
Figure 141 Float Waveforms
23.6 AC Characteristics
The parameters in this chapter partly represent the characteristics of the C165H and
partly its demands on the system. To aid in interpreting the table correctly when
evaluating parameters for a design, the following notation is used in the column
“Symbol”:
CC (Controller Characteristics):
The logic of the C165H will provide signals with the respective timing characteristics.
SR (System Requirement):
The external system must provide signals with the respective timing characteristics to
the C165H.
AC inputs during testing are driven at 2.4 V for a logic ‘1’ and 0.45 V for a logic ‘0’.
Timing measurements are made at VIH min for a logic ‘1’ and VIL max for a logic ‘0’.
0.45 V 0.8 V 0.8 V
2.0 V 2.0 V
Test Points
2.4 V
For timing purposes a port pin is no longer floating when a 100 mV change from load
voltage occurs, but begins to float when a 100 mV change from the loaded VOH/VOL l e v e l o c c u r s
(IOH/IOL = 20 mA).
Timing
Reference
Points
VOH -0.1 V
VOL +0.1 V
VLoad +0.1 V
VLoad -0.1 V
C165H
AC/DC Characteristics
Data Sheet 475 2001-04-19
PRELIMINARY
- EXCERPT -
23.6.1 Definition of Internal Timing
The internal operation of the C165H is controlled by the internal CPU clock fCPU. Both
edges of the CPU clock can trigger internal (eg. pipeline) or external (eg. bus cycles)
operations. The specification of the external timing (AC Characteristics) therefore
depends on the time between two consecutive edges of the CPU clock, called “TCL”
(see Figure 142).
Figure 142 Generation mechanisms for the CPU Clock
The CPU clock signal can be generated via different mechanisms. The mechanism used
to generate the CPU clock is selected during reset via the logic levels on pins P0.15-13
(P0H.7-5) and is described in detail in Chapter 3.3, page 36. The duration of TCLs and
their variation (and also the derived external timing) depends on the mechanism used to
generate fCPU. This influence must be regarded when calculating the timings for the
C165H.
Note: The example for PLL operation shown in Figure 142 refers to a PLL factor of 4.
The PLL multiplies the input frequency by the factor F which is selected via the
combination of pins P0.15-13 (ie. fCPU = fXTAL * F). With every F’th transition of fXTAL the
PLL circuit synchronizes the CPU clock to the input clock. This synchronization is done
smoothly, i.e. the CPU clock frequency does not change abruptly.
Due to this adaptation to the input clock, the frequency of fCPU is constantly adjusted so
it is locked to fXTAL. The slight variation causes a jitter of fCPU which also affects the
duration of individual TCLs.
The timings listed in the AC Characteristics that refer to TCLs therefore must be
calculated using the minimum TCL that is possible under the respective circumstances.
The actual minimum value for TCL depends on the jitter of the PLL. As the PLL is
constantly adjusting its output frequency so it corresponds to the applied input frequency
(crystal or oscillator), the relative deviation for periods of more than one TCL is lower
fCPU
fXTAL
Phase Locked Loop Operation
TCL
fCPU
fXTAL
Prescaler Operation
TCL
TCLTCL
C165H
AC/DC Characteristics
Data Sheet 476 2001-04-19
PRELIMINARY
- EXCERPT -
than for a single TCL. This is especially important for bus cycles using wait-states and
for the operation of timers, serial interfaces, etc. For all slower operations and longer
periods (eg. pulse train generation or measurement, lower baudrates, etc.), the deviation
caused by the PLL jitter is negligible.
23.6.2 System Reset
Figure 143 Reset Input and Output Signals
Note: Minimum reset time after power on is 1 ms after voltage reaches VDD minimum.
delayed until the end of the internal reset condition.
Current bus cycle is completed or aborted.
Activation of the IO pins is controlled by software.
Execution of the EINIT instruction.
When the internal reset condition is extended by RSTIN, the activation of the output signals is
Switches asinchronously with RSTIN, sinchronously upon software or watchdog reset.
The reset condition ends here. The C 167CR starts program execution.
The shaded area designates the internal reset sequence, which starts after synchronization of RSTIN.
RSTIN
Internal Reset Condition
6)
Initialization
3)
MCS02258
RD, WR
RSTOUT
IO
ALE
Bus
RSTIN
Internal Reset Condition
6)
1)
2)
2)
Initialization
3) 5)
4)
8)
7)
A short hardware reset is extended until the end of the reset sequence in Bidirectional reset mode.
A software or WDT reset activates the RSTIN line in Bidirectional reset mode.
8)
7)
6)
3)
2)
5)
4)
1)
C165H
AC/DC Characteristics
Data Sheet 477 2001-04-19
PRELIMINARY
- EXCERPT -
23.6.3 External Clock Drive XTAL1
VDD = 3.3 V ± 10%;VSS = 0 V
TA = -40 to +85 °C
Note: Special requirements for the external crystal must be observed: The accuracy of
the crystal must be 96ppm or better. Please note, the implemented low swing
crystal oscillator has a signal amplitude of only about 1 V peak-to-peak. More
detailed information can also be found in the appropriated application note.
Figure 144 External Clock Drive XTAL1
Table 79 External Clock Drive XTAL 1
Parameter Sym
bol
External crystal: 4-20 MHz
(internal oscillator "on",
PLL running)
Direct drive: 4-36 MHz
(internal oscillator by-passed,
PLL "free running" or "off")
Unit
min max min max
Oscillator period tOSCSR 50 250 27.8 250 ns
Duty Cycle - - 50 %
High time t1SR - - 13.9 125 ns
Low time t2SR - - 13.9 125 ns
Rise time t3SR - - - 3 @ 36 MHz ns
Fall time t4SR - - - 3 @ 36 MHz ns
MCT02534
3
t
4
t
V
IH2
V
IL
V
DD
0.5
1
t
2
t
OSC
t
C165H
AC/DC Characteristics
Data Sheet 478 2001-04-19
PRELIMINARY
- EXCERPT -
23.6.4 IOM-2 Interface Timing
Table 80 Timing Characteristics of IOM-2 Interface
Note: The input data (FSC and input DU and DD) are always sampled with the falling
edge of DCL/BCL. In case of DCL - FSC is sampled with the first falling edge and
DU/DD are sampled with the second falling edge of the bit frame.
Parameter CC /
SR
Symbol Limit Values Unit
min. max.
DCL, BCL data clock SR tr , tf60 ns
DCL, BCL clock period SR tDCL , tBCL 110 ns
DCL, BCL pulse width SR twH , twL 53 ns
FSC frame sync SR tr , tf60 ns
FSC frame setup SR tsF_DCL , tsF_BCL 70 ns
FSC frame hold SR thF_DCL, thF_BCL 40 ns
DOUT data delay/clock CC tdDC 1001)
1)condition: CL = 150 pF
ns
DOUT data setup SR tsD twH + 20 ns
DOUT data hold SR thD 50 150 ns
C165H
AC/DC Characteristics
Data Sheet 479 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 145 IOM-2 Interface Timing
BCL
DCL
FSC
DU/DD
Bit 0
BCL
DCL
FSC
DU/DD
DU/DD
output
input (DCL)
trtf
tf
thF_DCL
tsF_DCL
tdDC
tsF_BCL thF_BCL
thD
tsD
Bit 0 Bit 1Bit N
twH
twH
twL
twL
tDCL
tBCL
tsD
thD
DU/DD
input (BCL)
C165H
AC/DC Characteristics
Data Sheet 480 2001-04-19
PRELIMINARY
- EXCERPT -
23.6.5 JTAG Interface Timing
•
Figure 146 JTAG Interface Timing
Table 81 JTAG Interface Timing
No. Parameter Limit Values Unit
min. max.
200 TCK period 120 ns
201 TCK high time 60 ns
202 TCK low time 60 ns
203 TMS setup time 20 ns
204 TMS hold time 20 ns
205 TDI setup time 20 ns
206 TDI hold time 20 ns
207 TDO valid time 50 ns
TRST
TCK
TMS
TDI
TDO
202201
200
203
204
205
206
207
C165H
AC/DC Characteristics
Data Sheet 481 2001-04-19
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- EXCERPT -
23.7 Asynchronous Bus Timing
This term means that timing is defined with respect to ALE (as opposed to CLKOUT).
The following configurations are typical :
23.7.1 Memory Cycle Variables
The timing tables below use 4 variables which are derived from the BUSCONx registers
and represent the special characteristics of the programmed memory cycle. The
following table describes, how these variables are to be computed.
23.7.1.1 AC Characteristics, Multiplexed Bus
VDD = 3.3 V ± 10 %; VSS = 0 V
TA = -40 to +85 °C
CL (for PORT0, PORT1, Port 4, ALE, RD, WR, BHE, CLKOUT) = 100 pF
CL (for Port 6, CS) = 100 pF
ALE cycle time = 6 TCL + 2tA + tC + tF (83.3 ns at 36 MHz CPU clock without wait states)
Table 82 Asynchronous Bus Timing
RDY ALE WR MTTC RD/WR MCTC cycles Application BUSCON
no normal early no normal no 2 SRAMS demuxed
bus
0A3F (8) or
0ABF(16)
no normal - no normal 1 3 fast EPROMS
demuxed bus
0A3E /
0ABE
no normal - 1 normal 2 5 slow FLASH
demuxed bus
0A1D /
0A9D
no normal normal no delayed no 2+1 SRAMS muxed bus 04EF /
046F
no normal - no delayed 1 3+1 fast EPROMS
muxed bus
04EE /
046E
no normal - no delayed 2 4+1 slow FLASH muxed
bus
04ED /
046D
Table 83 Memory Cycle Variables
Description Symbol Values
ALE extension tATCL * <ALECTL>
memory cycle time waitstates tC2TCL * (15 - <MCTC>)
memory tristate time tF2TCL * (1 - <MTTC>)
early write tWTCL * <EWEN>
C165H
AC/DC Characteristics
Data Sheet 482 2001-04-19
PRELIMINARY
- EXCERPT -
Table 84 AC Characteristics, Multiplexed Bus
Parameter Symbol Max. CPU Clock
36 MHz (TCL=14ns)
Variable CPU Clock
5 to 36 MHz
Unit
min. max. min. max.
ALE high time t5CC 4 + tA–TCL - 10 + tA–ns
Address, CSx2) setup to ALE t6CC -6 + tA–TCL - 20 + tA–ns
Address hold after ALE t7CC 4 + tATCL - 10 + tAns
ALE falling edge to RD, WR
(with RW-delay)
t8CC 4 + tA–TCL - 10 + tA–ns
ALE falling edge to RD, WR
(no RW-delay)
t9CC -10 + tA–-10 + tA–ns
Address float after RD, WR
(with RW-delay)
t10 CC –15 –15 ns
Address float after RD, WR
(no RW-delay)
t11 CC –29 –TCL + 15 ns
RD, WR low time
(with RW-delay) 3)
t12 CC 17 + tC -
tW
–2TCL - 11 + tC
- tW
–ns
RD, WR low time
(no RW-delay) 3)
t13 CC 31 + tC -
tW
–3TCL - 11 + tC
- tW
–ns
RD to valid data in
(with RW-delay)
t14 SR –0 + tC–2TCL - 28 +
tC
ns
RD to valid data in
(no RW-delay)
t15 SR –13 + tC–3TCL - 29 +
tC
ns
ALE low to valid data in t16 SR –13 + tA +
tC
–3TCL - 29 +
tA + tC
ns
Address, CSx2) to valid data
in
t17 SR –18 + 2tA
+ tC
–4TCL - 38 +
2tA + tC
ns
Data hold after RD
rising edge
t18 SR 0–0–ns
Data float after RD t19 SR –13 + tF–2TCL - 15 +
tF
ns
Data valid to WR t22 CC 13 + tC -
tW
–2TCL - 15 + tC
- tW
–ns
Data hold after WR t23 CC 13 + tF +
tW
–2TCL - 15 + tF
+ tW
–ns
ALE rising edge after RD,
WR 3)
t25 CC 13 + tF +
tW
–2TCL - 15 + tF
+ tW
–ns
C165H
AC/DC Characteristics
Data Sheet 483 2001-04-19
PRELIMINARY
- EXCERPT -
1) Normal (latched) CS: bit CSCFG, register SYSCON.6, is set to ’0’, latched mode is selcted.
2) Early (unlatched) CS; (bit CSCFG = ’1’) while address bus is changing spikes may occur on CS in this mode.
3) The memory cycle variable tW applies only for write accesses; for read accesses this variable is always zero.
Address hold after RD, WR 3) t27 CC 13 + tF +
tW
–2TCL - 15 + t F
+ tW
–ns
ALE falling edge to CSx1) t38 CC -9 - tA13 - tA-9 - tA13 - tAns
CSx1) low to Valid Data In t39 SR –12 + tC
+ 2tA
– 3TCL - 30
+ tC+2tA
ns
CSx1) hold after RD, WR 3) t40 CC 27 + tF +
tW
–3TCL - 15 + t F
+ tW
–ns
ALE falling edge to RdCS,
WrCS (with RW delay)
t42 CC 5 + tA–TCL - 9 + tA–ns
ALE falling edge to RdCS,
WrCS (no RW delay)
t43 CC -9 + tA–-9 + tA–ns
Address float after RdCS,
WrCS (with RW delay)
t44 CC – 13 – 13 ns
Address float after RdCS,
WrCS (no RW delay)
t45 CC – 27 – TCL + 13 ns
RdCS to Valid Data In (with
RW delay)
t46 SR –-4 + tC– 2TCL - 32
+ tC
ns
RdCS to Valid Data In (no RW
delay)
t47 SR –10 + tC– 3TCL - 32
+ tC
ns
RdCS, WrCS Low Time (with
RW delay) 3)
t48 CC 14 + tC -
tW
– 2TCL - 14 + tC
- tW
–ns
RdCS, WrCS Low Time (no
RW delay) 3)
t49 CC 30 + tC -
tW
– 3TCL - 12 + tC
- tW
–ns
Data valid to WrCS t50 CC 13 + tC -
tW
– 2TCL - 15 + tC
- tW
–ns
Data hold after RdCS t51 SR 0–0 – ns
Data float after RdCS t52 SR –7 + tF– 2TCL - 21
+ tF
ns
Address hold after RdCS,
WrCS 3)
t54 CC 8 + tF +
tW
–2TCL - 20 + t F
+ tW
–ns
Data hold after WrCS t56 CC 8 + tF +
tW
–2TCL - 20 + t F
+ tW
–ns
Table 84 AC Characteristics, Multiplexed Bus (cont’d)
Parameter Symbol Max. CPU Clock
36 MHz (TCL=14ns)
Variable CPU Clock
5 to 36 MHz
Unit
min. max. min. max.
C165H
AC/DC Characteristics
Data Sheet 484 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 147 External Memory Cycle: Multiplexed Bus, With Read/Write Delay,
Normal ALE
Data In
Data OutAddress
Address
t38
t44
t10
Address
ALE
BUS
Read Cycle
RD
RdCSx
BUS
Write Cycle
WR,
WRL, WRH
WrCSx
t5t16
t17
t6t7
t39
t25
t18
t19
t14
t46
t12
t48
t10 t22
t23
t44
t12
t48
t8
t42
t42
t8
t50
t51
t52
t56
t27
t40
t54
CSx1)
A23-A16
(A15-A8)
CSx2), BHE
C165H
AC/DC Characteristics
Data Sheet 485 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 148 External Memory Cycle: Multiplexed Bus, With Read/Write Delay,
Extended ALE
Data OutAddress
Data InAddress
t38
t44
t10
Address
ALE
BUS
Read Cycle
RD
RdCSx
BUS
Write Cycle
WR,
WRL, WRH
WrCSx
t5t16
t17
t6t7
t39
t25
t18
t19
t14
t46
t12
t10 t22
t23
t44
t12
t8
t42
t42
t8
t50
t51
t52
t56
t27
t40
t54
t48
t48
CSx1)
A23-A16
(A15-A8)
CSx2), BHE
C165H
AC/DC Characteristics
Data Sheet 486 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 149 External Memory Cycle: Multiplexed Bus, No Read/Write Delay,
Normal ALE
Data OutAddress
Address Data In
t38
Address
ALE
CSx1)
A23-A16
(A15-A8)
CSx2),BHE
BUS
Read Cycle
RD
RdCSx
BUS
Write Cycle
WR,
WRL, WRH
WrCSx
t5t16
t17
t6t7
t39
t18
t19
t15
t47
t13
t49
t22
t23
t13
t49
t9
t43
t43
t9t11
t45
t11
t45 t50
t51
t52
t56
t25
t27
t40
t54
C165H
AC/DC Characteristics
Data Sheet 487 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 150 External Memory Cycle: Multiplexed Bus, No Read/Write Delay,
Extended ALE
Data OutAddress
Data InAddress
t38
Address
ALE
CSx1)
A23-A16
(A15-A8)
CSx2),BHE
BUS
Read Cycle
RD
RdCSx
BUS
Write Cycle
WR,
WRL, WRH
WrCSx
t5t16
t17
t6t7
t39
t25
t18
t19
t15
t47
t13
t49
t22
t23
t13
t49
t9
t43
t43
t9t11
t45
t11
t45 t50
t51
t52
t56
t27
t40
t54
C165H
AC/DC Characteristics
Data Sheet 488 2001-04-19
PRELIMINARY
- EXCERPT -
23.7.1.2 AC Characteristics, Demultiplexed Bus
VDD = 3.3 V ± 10 %;VSS = 0 V
TA = -40 to +85 °C
CL (for PORT0, PORT1, Port 4, ALE, RD, WR, BHE, CLKOUT) = 100 pF
CL (for Port 6, CS) = 100 pF
ALE cycle time = 4 TCL + 2tA + tC + tF (55.5 ns at 36 MHz CPU clock without waitstates)
Table 85 AC Characteristics, Demultiplexed Bus
Parameter Symbol Max. CPU Clock
= 36 MHz (TCL=14ns)
Variable CPU Clock
5 to 36 MHz
Unit
min. max. min. max.
ALE high time t5CC 4 + tA– TCL - 10 + tA–ns
Address, CSx4) setup to
ALE
t6CC -6 + tA– TCL - 20 + tA–ns
ALE falling edge to RD,
WR (with RW-delay)
t8CC 4 + tA– TCL - 10 + tA–ns
ALE falling edge to RD,
WR (no RW-delay)
t9CC -10 + tA– -10 + tA–ns
RD, WR low time (with
RW-delay) 6)
t12 CC 17 + tC - tW – 2TCL - 11 + tC -
tW
–ns
RD, WR low time (no RW-
delay) 6)
t13 CC 31 + tC - tW– 3TCL - 11 + t C -
tW
–ns
RD to valid data in (with
RW-delay)
t14 SR –0 + tC– 2TCL - 28 +
tC
ns
RD to valid data in (no
RW-delay)
t15 SR – 13 + tC– 3TCL - 29 +
tC
ns
ALE low to valid data in t16 SR – 13 + tA +
tC
– 3TCL - 29 +
tA + tC
ns
Address, CSx4) to valid
data in
t17 SR – 16 + 2tA
+ tC
– 4TCL - 40 +
2tA + tC
ns
Data hold after RD rising
edge
t18 SR 0–0 – ns
Data float after RD rising
edge (with RW-delay 1))
t20 SR – 14 + tF– 2TCL - 14 +
2tA + tF 1)
ns
Data float after RD rising
edge (no RW-delay 1))
t21 SR –4 + tF–TCL - 10 +
2tA + tF 1)
ns
Data valid to WR t22 CC 13 + tC - tW– 2TCL - 15 + t C -
tW
–ns
Data hold after WR t24 CC 4 + tF + tW– TCL - 10 + tF +
tW
–ns
C165H
AC/DC Characteristics
Data Sheet 489 2001-04-19
PRELIMINARY
- EXCERPT -
1) RW-delay and tA refer to the next following bus cycle.
ALE rising edge after RD,
WR 6)
t26 CC 0 + tF + tW–0 + tF + tW–ns
Address, CSx4) hold after
WR 2) 5)
t28 CC 0 + tF + tW–0 + tF + tW–ns
ALE falling edge to CSx3) t38 CC -9 - tA13 - tA-9 - tA13 - tAns
CSx3) low to Valid Data In t39 SR – 12 + t C +
2tA
– 3TCL - 30 +
tC+2tA
ns
CSx3) hold after RD, WR 6) t41 CC 0 + tF + tW–TCL - 14 + tF +
tW
–ns
ALE falling edge to
RdCS, WrCS (with RW-
delay)
t42 CC 5 + tA–TCL - 9 + tA–ns
ALE falling edge to
RdCS, WrCS (no RW-
delay)
t43 CC -9 + tA–-9 + tA–ns
RdCS to Valid Data In
(with RW-delay)
t46 SR –-4 + tC– 2TCL - 32 +
tC
ns
RdCS to Valid Data In (no
RW-delay)
t47 SR – 10 + tC–3TCL
- 32 +
tC
ns
RdCS, WrCS Low Time
(with RW-delay) 6)
t48 CC 14 + tC - tW– 2TCL - 14 + tC -
tW
–ns
RdCS, WrCS Low Time
(no RW-delay) 6)
t49 CC 30 + tC - tW– 3TCL - 12 + tC -
tW
–ns
Data valid to WrCS t50 CC 13 + tC - tW– 2TCL - 15 + tC -
tW
–ns
Data hold after RdCS t51 SR 0–0 – ns
Data float after RdCS
(with RW-delay 1))
t53 SR –7 + tF– 2TCL - 21 +
tF
ns
Data float after RdCS (no
RW-delay 1))
t68 SR –0 + tF– TCL - 14 +
tF
ns
Address hold after
WrCS2)
t55 CC -14 + tF +
tW
– - 14 + tF + tW–ns
Data hold after WrCS t57 CC 0 + tF + tW–TCL - 14 + tF +
tW
–ns
Table 85 AC Characteristics, Demultiplexed Bus (cont’d)
Parameter Symbol Max. CPU Clock
= 36 MHz (TCL=14ns)
Variable CPU Clock
5 to 36 MHz
Unit
min. max. min. max.
C165H
AC/DC Characteristics
Data Sheet 490 2001-04-19
PRELIMINARY
- EXCERPT -
2) Read data are latched with the same clock edge that triggers the address change and the rising RD, RDCS
edge. Therefore address changes before the end of RD, RDCS have no impact on read cycles.
3) Normal (latched) CS: bit CSCFG, register SYSCON.6, is set to ’0’, latched mode is selcted.
4) Early (unlatched) CS (bit CSCFG = ’1’); while address bus is changing spikes may occur on CS in this mode.
5) Demultiplexed cycles: In case of early (unlatched) CS together with normal write (not early write) CS may go
inactive 3 ns before the rising edge of WR .
6) The memory cycle variable tW applies only for write accesses; for read accesses this variable is always zero.
C165H
AC/DC Characteristics
Data Sheet 491 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 151 External Memory Cycle: Demultiplexed Bus, With Read/Write Delay,
Normal ALE
Data Out
Data In
t38
Address
ALE
CSx3)
A23-A16
A15-A0
CSx4), BHE
BUS
(D15-D8)
D7-D0
Read Cycle
RD
RdCSx
Write Cycle
WrCSx
t5t16
t17
t6
t39
t28
t18
t20
t14
t46
t12
t48
t22
t24
t12
t48
t8
t42
t42
t8
t50
t51
t55
t53
t57
BUS
(D15-D8)
D7-D0
WR,
WRL, WRH
t26
t41
C165H
AC/DC Characteristics
Data Sheet 492 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 152 External Memory Cycle: Demultiplexed Bus, With Read/Write Delay,
Extended ALE
Data Out
Data In
t38
Address
ALE
CSx3)
A23-A16
A15-A0
CSx4), BHE
Read Cycle
RD
RdCSx
Write Cycle
WrCSx
t5t16
t17
t6
t39
t28
t18
t20
t14
t46
t12
t48
t22
t24
t12
t48
t8
t42
t42
t8
t50
t51
t55
t53
t57
BUS
(D15-D8)
D7-D0
BUS
(D15-D8)
D7-D0
WR,
WRL, WRH
t26
t41
C165H
AC/DC Characteristics
Data Sheet 493 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 153 External Memory Cycle: Demultiplexed Bus, No Read/Write Delay,
Normal ALE
Data Out
Data In
t38
Address
ALE
CSx3)
A23-A16
A15-A0
CSx4),BHE
Read Cycle
RD
RdCSx
Write Cycle
WrCSx
t5t16
t17
t6
t39
t28
t18
t21
t15
t47
t13
t49
t22
t24
t13
t49
t9
t43
t43
t9
t50
t51
t55
t68
t57
BUS
(D15-D8)
D7-D0
BUS
(D15-D8)
D7-D0
WR,
WRL,WRH
t26
t41
C165H
AC/DC Characteristics
Data Sheet 494 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 154 External Memory Cycle: Demultiplexed Bus, No Read/Write Delay,
Extended ALE
Data Out
Data In
t38
Address
ALE
CSx3)
A23-A16
A15-A0
CSx4),BHE
Read Cycle
RD
RdCSx
Write Cycle
WR,
WRL, WRH
WrCSx
t5t16
t17
t6
t39
t28
t18
t21
t15
t47
t13
t49
t22
t24
t13
t49
t9
t43
t43
t9
t50
t51
t55
t68
t57
BUS
(D15-D8)
D7-D0
BUS
(D15-D8)
D7-D0
t26
t41
C165H
AC/DC Characteristics
Data Sheet 495 2001-04-19
PRELIMINARY
- EXCERPT -
23.7.1.3 AC Characteristics, CLKOUT and READY
VDD = 3.3 V ± 10 %;VSS = 0 V
TA = -40 to +85 °C
CL (for PORT0, PORT1, Port 4, ALE, RD, WR, BHE, CLKOUT, READY) = 100 pF
CL (for Port 6, CS) = 100 pF
Note: Timing parameters for 36-MHz clock are based on the assumption that the
oscillator is running at 8 MHz and PLL with F = 4.5.
1) These timings are given for test purposes only, in order to assure recognition at a specific clock edge.
2) Demultiplexed bus is the worst case. For multiplexed bus, 2 TCL is to be added to the maximum values. This
adds even more time for deactivating READY.
Note: The 2tA and tC refer to the next following bus cycle, tF refers to the current bus
cycle.
Table 1
AC Characteristics, CLKOUT and READY
Parameter Symbol CPU Clock
36 MHz (TCL = 14ns)
Variable CPU Clock
5 to 36 MHz
Unit
min. max. min. max.
CLKOUT cycle time t29 CC 27 29 2TCL - 1 2TCL + 1 ns
CLKOUT high time t30 CC 8 – TCL – 6 – ns
CLKOUT low time t31 CC 4 – TCL – 10 – ns
CLKOUT rise time t32 CC –4 – 4 ns
CLKOUT fall time t33 CC –4 – 4 ns
CLKOUT rising edge to
ALE falling edge
t34 CC 0 + tA16 + tA0 + tA16 + tAns
Synchronous READY
setup time to CLKOUT
t35 SR 18 – 18 – ns
Synchronous READY
hold time after CLKOUT
t36 SR 0– 0 – ns
Asynchronous READY
low time
t37 SR 45 – 2TCL +
17
–ns
Asynchronous READY
setup time 1)
t58 SR 18 – 18 – ns
Asynchronous READY
hold time 1)
t59 SR 0– 0 – ns
Async. READY hold time
after RD, WR high
(Demultiplexed Bus) 2)
t60 SR 0 -10 + 2tA + tC
+ tF
2)
0TCL - 24 + 2tA +
tC + tF
2)
ns
C165H
AC/DC Characteristics
Data Sheet 496 2001-04-19
PRELIMINARY
- EXCERPT -
Figure 155 CLKOUT and READY
1) Cycle as programmed, including MCTC wait states (Example shows 0 MCTC WS).
2) The leading edge of the respective command depends on RW-delay.
3) READY sampled HIGH at this sampling point generates a READY controlled wait state. READY sampled
LOW at this sampling point terminates the bus cycle currently running.
4) READY may be deactivated in response to the trailing (rising) edge of the corresponding command (RD or
WR).
5) If the Asynchronous READY signal does not fulfill the indicated setup and hold times with respect to CLKOUT
(eg. because CLKOUT is not enabled), it must fulfill t37 in order to be safely synchronized. This is guaranteed
if READY is removed in reponse to the command (see Note 4)).
6) Multiplexed bus modes have a MUX wait state added after a bus cycle, and an additional MTTC wait state may
be inserted here. For a multiplexed bus with MTTC wait state, this delay is 2 CLKOUT cycles, for a
demultiplexed bus without MTTC wait state this delay is zero.
7) The next external bus cycle may start here.
CLKOUT
ALE
t30
t34
Sync
READY
t35 t36 t35 t36
Async
READY
t58 t59 t58 t59
waitstate
READY
MUX/Tristate 6)
t32 t33
t29
Running cycle 1)
t31
t37
3) 3)
5)
Command RD, WR
t60 4)
see 6)
2)
7)
3) 3)
C165H
Package Outline
Data Sheet 497 2001-04-19
PRELIMINARY
- EXCERPT -
24 Package Outline
P-TQFP-144
(Plastic Thin Quad Flat Package)
C165H
Package Outline
Data Sheet 498 2001-04-19
PRELIMINARY
- EXCERPT -
http://www.infineon.com
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Infineon Technologies AG - Products-C165 H (HDLC)--~SAFC165H-LF
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Home > Products > Wired Communication Customer Premises Equipment > ISDN CPE
> SAFC165H-LF
The C165H is a new low-cost
member of the Infineon
Communication Controller
family
The device combines the
successful Infineon C166 16-bit
full static core with four
independent HDLC controllers,
IOM-2 interface and 3-Kbyte of
on-chip Dual-Port RAM. The
C165H addresses all embedded
HDLC features in ISDN-TA,
Intelligent-NT and low cost
SOHO-PBX designs offering up
to 18 MIPS along with legacy
peripherals, such as USART,
SSC/SCI and Timers. The
C165H device core has a built-in
DMA, which provides maximum
flexibility and performance. Off-
loading the CPU in such a
manner allows the user to
implement value add software
features enabling product
differentiation.
Links:
List of tools providers and 3rd
party SW providers
C165 H (HDLC) -- SAFC165H-LF
16-bit Microcontroller with HDLC and IOM-2
Features:
● Full-static core up to 18 MIPS (@ 36 MHz)
● Peripheral Event Controller (PEC) for 8 independent DMA channels
● IOM-2/PCM interface supporting TE, LT and PCM mode
● JTAG Boundary Scan Test Support according to IEEE 1149.1
● 3.3 V Single Supply Voltage, 5V (TTL-) Tolerant I/Os
Typelist (for details see Parameterlist)
Product Type Description Order Info To Distributor
SAFC165H-LF 16-Bit Microcontroller with HDLC Q67003H9459
Additional Documentation and Information:
Product Brief
Description Date/State Size
C165H Product Brief
(C165H.pdf) 02-2000 223 kB
Datasheet
Description Date/State Size
SAF C165 H
(safc165h.pdf) 04-2001 6 MB
Addendum to the C165H Dta Sheet, DS1
(C165H_ds1_v13addendum.pdf) 07-2002 125 kB
Application Notes
Description Date/State Size
Crystal Oscillator of the C500 and C166 Microcontroller Families
(ap242005.pdf) 07-1999 654 kB
Cristal Oscillator of C165UTAH/H and C161U
(crist-osc_13a.pdf) 11-2000 815 kB
Use of external crystals
(ExtCryst_13a.pdf) 11-2000 8.86 kB
EMC Design Guideline for Microcontroller Board Layout V.2
(ap242602_EMC_DesignGuideline.pdf) 04-2001 826 kB
EMC Design Guideline 2 for Microcontroller Board Layout V.1
(emcguideline1_0.pdf) 07-1999 298 kB
EMC Design Guideline 3 for Microcontroller Board Layout V.1
(ap242101.pdf) 07-1999 298 kB
EMC Addendum
(emcaddendum.pdf) 06-2000 34 kB
EMC by Simulation
(ap242101.pdf) 04-1997 288 kB
Understanding the IOM-2 interrupt structure including code files
IOMINT.C and IOMDEF.H
(c165utah-iom2_13a.pdf) 11-2000 703 kB
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Infineon Technologies AG - Products-C165 H (HDLC)--~SAFC165H-LF
Understanding the IOM-2 interrupt structure Code File IOMINT.C
(IOMINT.c) 06-2001 13.5 kB
Understanding the IOM-2 interrupt structure Code File H
(Iomdef.h) 06-2001 16.9 kB
Use of FIFOs in the IOM2 Module of the C165H/UTAH
(fifo.pdf) 11-2000 620 kB
Keil and Tasking Code 2
(UTAH-Autobaud-Code-2_1.zip) 07-2001 556 kB
Keil and Tasking Code 1
(UTAH-Autobaud-Code-1_1.zip) 07-2001 3.52
MB
ASC Autobaud Detection
(c165uh_ds1_v13a_1.pdf) 07-2001 260 kB
Development Tools
Description Date/State Size
SAF C165 UTAH Evaluation Board: Tool description
(syaa_12i.pdf) 09-2001 270 kB
Better way to develop and debug system- OCDS based
(C165UTAH_C165H_C161U_OCDS1.pdf) 06-2000 1.55
MB
Device Driver for IOM2
(codes_for_IOM-2_drivers.ZIP) 10-2001 1.19
MB
Documentation for IOM-2 driver
(IOM2_Software_Users_Manual.pdf) 08-2001 974 kB
For additional tooling information refer to "www.spacetools.com" 06-2001 0 Byte
Errata Sheet
Description Date/State Size
Please contact your local sales partner 04-2002 0 Byte
Additional Information
Description Date/State Size
Solution Guide ISDN Data Access
(data_access_solution_guide.pdf) 01-2002 702 kB
Solution Guide for SOHO PBX
(soho_solution_guide_pub_ds2.pdf) 01-2004 638 kB
Solution Guide for Intelligent Network Terminators
(iNT_Intelligent_Network_Termination_ds2.pdf) 06-2002 576 kB
Solution Guide for Terminal Adapter
(Terminal_Adapter_solution_guide_public.pdf) 06-2002 649 kB
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