Adaptation Layer Controller
The FUJITSU MB86687A is an ATM protocol controller
which autonomously terminates ATM Adaptation Layer
standards Type 3/4 and Type 5. The device is ideally suited
to applications in a variety of customer premises equipment
such as ATM workstation Adaptor Cards and ATM Hubs.
The device supports simultaneous segmentation and
reassembly on up to 1024 virtual circuits (VCs).
FEATURES
Supports Broadband ISDN Adaptation Layer standards T ype
3/4 and Type 5.
Supports simultaneous segmentation and reassembly on up
to 1024 VCs.
Supports up to 12 peak segmentation rates with leaky bucket
averaging on a per VC basis with optional bucket fill before
segmentation continues.
Programmable peak and average rates and leaky bucket
averaging on total ALC cell stream output.
Support for scatter / gather mode.
Transparent ATM cell and cell payload modes including
support for OAM and Resource Management cells.
UTOPIA Level 1 v2.01 functionally compatible cell stream
interface with optional HEC checking on receive.
Flexible routing tag append / remove mode for direct ATM
Switch connection.
Supports buffer chaining and buffer streaming.
Supports buffer ageing time-out.
Separate 32 bit data and 16 bit control ports with optimized
DMA interface including 128 circuit cache to reduce DMA bus
occupancy.
Supports JTAG to IEEE1149.1
Fabricated in sub–micron CMOS technology with CMOS/TTL
compatible I/O and single +5V power supply.
This device contains circuitry to protect the inputs
against damage due to high static voltages or
electric fields. However, it is advised that normal
precautions be taken to avoid application of any
voltage higher than maximum rated voltages to
this high impedance circuit.
PLASTIC PACKAGE
SQFP208
PIN ASSIGNMENT
1
156
157
208 52
53
104
105
INDEX
Adaptation Layer Controller (ALC)
DATA SHEET
Edition 2.0
April 1996
MB86687A
COPYRIGHT
1996 BY FUJITSU LIMITED
TABLE OF CONTENTS
MB86687A Edition 2.0
i
CONTENTS
1. OVERVIEW 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2. EXTERNAL INTERFACES 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.1 Logical Outline 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2 Detailed Description 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3. FUNCTIONAL DESCRIPTION 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1 DMA Controller and SAR Memory Interface 9. . . . . . . . . . .
3.2 Traffic Management Controller 15. . . . . . . . . . . . . . . . . . . . . .
3.3 Segmentation and Convergence Sub-layer Controller 17.
3.4 Reassembly and Convergence Sub-layer Controller 21. .
3.5 Cell Stream Interface 22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.6 Microprocessor Interface 26. . . . . . . . . . . . . . . . . . . . . . . . . . .
3.7 Segmentation and Reassembly Memory Interface 27. . . . .
4. DEVELOPERS NOTES 33. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.1 Configuration Control Issues 33. . . . . . . . . . . . . . . . . . . . . . . .
4.2 Transmit Data Structures 33. . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.3 Receive Data Structures 45. . . . . . . . . . . . . . . . . . . . . . . . . . . .
APPENDICES
A. REGISTER TABLE 52. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B. REGISTER MAPS 56. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
C. RA TINGS 83. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
C.1 Absolute Maximum Ratings 83. . . . . . . . . . . . . . . . . . . . . . . . .
C.2 DC Characteristics 83. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
D. AC TIMINGS 84. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
E. JT AG 106. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
E.1 JTAG Cells 106. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
F. PIN DESCRIPTION 110. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
F.1 Physical Pin Diagram 110. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
F.2 Pin Description Table 111. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
G. PACKAGE DIMENSIONS 115. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TABLE OF CONTENTS MB86687AEdition 2.0
ii
TABLES
Table 1 – Pull Values 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 2 – Single Buffer, Chaining and Streaming Modes 13. . . . . . . . . . . . . . . . . . . . .
Table 3 – JTAG Interface Timing 84. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 4 – Miscellaneous – AC Timing Parameters 84. . . . . . . . . . . . . . . . . . . . . . . . . .
Table 5 – Cell Stream Interface clocks – AC Timing Parameters 85. . . . . . . . . . . . . .
Table 6 – Cell Stream Interface Fujitsu Mode – AC Timing Parameters 86. . . . . . . .
Table 7 – Cell Stream Interface UTOPIA Mode – AC Timing Parameters 87. . . . . . .
Table 8 – Cell Stream Interface Token Passing – AC Timing Parameters 88. . . . . . .
Table 9 – Microprocessor Interface – AC Timing 90. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 10 – Microprocessor Interface – AC Timing 91. . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 11 – Microprocessor Interface – Intel DMA Access AC Timing 93. . . . . . . . . .
Table 12 – Microprocessor Interface – Motorola DMA Access AC Timing 95. . . . . .
Table 13 – DPR / DMA Interface – Intel Cycle AC Timing 98. . . . . . . . . . . . . . . . . . . .
Table 14 – DPR / DMA Interface – Motorola Cycle AC Timing 101. . . . . . . . . . . . . . . .
Table 15 – Single Cycle Burst – Intel Extended Cycle Timing 103. . . . . . . . . . . . . . . . .
Table 16 – Single Cycle Burst – Motorola Extended Cycle Timing 105. . . . . . . . . . . . .
FIGURES
Fig. 1 – Possible System Configurations 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 2 – ALC External Interfaces 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 3 – ALC Block Diagram 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 4 – Shared Data Structures 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 5 – Transmit Queue Structure 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 6 – ATM Protocol Data Units (a) AAL3/4 (b) AAL5 17. . . . . . . . . . . . . . . . . . . . . .
Fig. 7 – Convergence Sub-layer Protocol Data Units 18. . . . . . . . . . . . . . . . . . . . . . . .
Fig. 8 – Cell Stream Interface 21. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 9 – Cell Stream Receive Interface Timing 23. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 10 – UTOPIA Transmit Interface Timing 23. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 11 – UTOPIA Receive Interface Timing 23. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 12 – CSI Token In/Out Timing 24. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 13 – Motorola 32 Bit Mode – Normal Mode Read Timing 28. . . . . . . . . . . . . . . . .
Fig. 14 – Intel 32 Bit Mode – Normal Mode Extended Read Timing 28. . . . . . . . . . . .
Fig. 15 – Intel 486 Mode – Normal Reads Timing 29. . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 16 – Intel 486 Mode Single Cycle Burst Timing 29. . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 17 – Start of Cycle Signal Timing – Fast Mode Extended Read 30. . . . . . . . . . .
Fig. 18 – Transmit Data Structures 34. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 19 – Transmit Data Structures – Address Calculation 35. . . . . . . . . . . . . . . . . . .
Fig. 20 – Transmit Descriptor 36. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 21 – Circuit Reference Table Entry 39. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TABLE OF CONTENTS
MB86687A Edition 2.0
iii
FIGURES (CONTINUED)
Fig. 22 – ALC Queue Structures 42. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 23 – Transmit Pending Queue Format 43. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 24 – Transmit Buffer Release Queue Format 44. . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 25 – Receive Data Structures 46. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 26 – Receive Data Structures – Address Calculation 47. . . . . . . . . . . . . . . . . . . .
Fig. 27 – Receive Descriptor 48. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 28 – Buffer Free Queue Format 49. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 29 – Receive Buffer Ready Queue Format 50. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 30 – ALC REGISTER MAP (1 of 3) 53. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 31 – ALC REGISTER MAP (2 of 3) 54. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 32 – ALC REGISTER MAP (3 of 3) 55. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 33 – REGISTERS 0, 1 AND 2 56. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 34 – REGISTER 3, 4 AND 5 57. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 35 – REGISTER 6, 7 AND 8 58. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 36 – REGISTERS 9 and 10 59. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 37 – REGISTER 13 60. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 38 – REGISTER 14 61. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 39 – REGISTER 15 62. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 40 – REGISTER 15 contd. 63. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 41 – REGISTER 16 64. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 42 – REGISTER 16 contd. 65. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 43 – REGISTER 17 66. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 44 – REGISTER 17 (continued) 67. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 45 – REGISTER 18 68. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 46 – REGISTER 18 (continued) and 19 69. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 47 – REGISTERS 20 to 31 70. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 48 – REGISTER 32 71. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 49 – REGISTER 33 AND 34 72. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 50 – REGISTER 35 73. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 51 – REGISTERS 40 and 41 74. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 52 – REGISTER 42, 43 AND 44 75. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 53 – REGISTER 45, 46 AND 47 76. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 54 – REGISTER 48, 49 AND 50 77. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 55 – REGISTERS 51 AND 52 78. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 56 – REGISTER 53 AND 54 79. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 57 – REGISTER 55 AND 56 80. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 58 – REGISTER 57 AND 58 81. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 59 – REGISTER 59 82. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 60 – System Clock Timing 84. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TABLE OF CONTENTS MB86687AEdition 2.0
iv
FIGURES (CONTINUED)
Fig. 61 – Reset Timing 84. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 62 – Cell Stream Clock Timing 85. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 63 – Cell Stream Interface Transmit Port (Fujitsu Mode) Timing 86. . . . . . . . . .
Fig. 64 – Cell Stream Interface Receive Port (Fujitsu Mode) Timing 86. . . . . . . . . .
Fig. 65 – Cell Stream Interface Transmit Port (Utopia mode) Timing 87. . . . . . . . . . .
Fig. 66 – Cell Stream Interface Receive Port (Utopia mode) Timing 87. . . . . . . . . . .
Fig. 67 – CSI Token Transmit and Receive Timing 88. . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 68 – Microprocessor Interface – Read Timing 89. . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 69 – Microprocessor Interface – Write Timing 89. . . . . . . . . . . . . . . . . . . . . . . . . .
Fig. 70 – Microprocessor Interface – Write to Write Timing 91. . . . . . . . . . . . . . . . . . .
Fig. 71 – Microprocessor Interface – Interrupt Timing 91. . . . . . . . . . . . . . . . . . . . . . .
Fig. 72 – Microprocessor Interface – Intel DMA Access Timing (SYNC) 92. . . . . . . .
Fig. 73 – Microprocessor Interface – Intel DMA Access Timing (ASYNC) 92. . . . . .
Fig. 74 – Microprocessor Interface – Intel DMA Access Control Override Timing 93
Fig. 75 – Microprocessor Interface – Motorola DMA Access Timing (SYNC) 94. . . .
Fig. 76 – Microprocessor Interface – Motorola DMA Access Timing (ASYNC) 94. .
Fig. 77 – DPR / DMA Interface – Intel Read Cycle (SYNC) 96. . . . . . . . . . . . . . . . . . .
Fig. 78 – DPR / DMA Interface – Intel Read Cycle (ASYNC) 96. . . . . . . . . . . . . . . . .
Fig. 79 – DPR / DMA Interface – Intel Write Cycle (SYNC) 97. . . . . . . . . . . . . . . . . . .
Fig. 80 – DPR / DMA Interface – Intel Write Cycle (ASYNC) 97. . . . . . . . . . . . . . . . .
Fig. 81 – DPR / DMA Interface – Motorola Read Cycle (SYNC) 99. . . . . . . . . . . . . . .
Fig. 82 – DPR / DMA Interface – Motorola Read Cycle (ASYNC) 99. . . . . . . . . . . . .
Fig. 83 – DPR / DMA Interface – Motorola Write Cycle (SYNC) 100. . . . . . . . . . . . . . .
Fig. 84 – DPR / DMA Interface – Motorola Write Cycle (ASYNC) 100. . . . . . . . . . . . .
Fig. 85 – Single Cycle Burst – Intel Extended Cycle (SBL=0, SYNC) 102. . . . . . . . . .
Fig. 86 – Single Cycle Burst – Intel Extended Cycle (SBL=0, ASYNC) 102. . . . . . . . .
Fig. 87 – Single Cycle Burst – Motorola Extended Cycle (SBL=0, SYNC) 104. . . . . .
Fig. 88 – Single Cycle Burst – Motorola Extended Cycle (SBL=0, ASYNC) 104. . . . .
Fig. 89 – ALC Pin Assignment 110. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Edition 2.0 MB86687A
1
1. OVERVIEW
The ALC simultaneously supports
autonomous segmentation and
reassembly of user data packets on up to
1024 virtual circuits (VCs).
User data packets are transferred to and
from shared data structure memory
using a high speed intelligent DMA
controller with a 32 bit data bus.
Shared data structures are stored in SAR
(Segmentation and Reassembly)
memory which can be either dual port
memory or a partition of system memory .
Packets for segmentation and packets
being reassembled are stored in the SAR
memory together with external data
structures. These are accessed using the
ALC’s high speed intelligent DMA
controller. In non-demanding
applications, system memory can be
used as SAR memory. When dual port
memory is used the ALC’s DMA
controller has full access to the SAR
memory bus. When system memory is
used the DMA controller will negotiate
access to a portion of the system bus
bandwidth. The ALC provides the user
with the facility to partition the shared
data structures into dual port memory
and user data into shared memory.
The DMA controller supports
autonomous traffic shaping functions.
Up to twelve different peak rate queues
can be configured for packet
segmentation. In addition each VC can
be assigned to either 100%, 50% or 25%
of the nominal peak rate.
In this way the user can select from one of
36 possible peak rates. Average rate
management is in accordance with either
the single or double leaky bucket
averaging algorithms.
Fig. 1 shows three possible system
configurations.
Adaptation Layer Support
The ALC autonomously terminates the
protocols involved in segmenting and
reassembling data streams conforming
to Adaptation Layer Types 3/4 and 5. AAL
3/4 and AAL 5 traffic can be handled
simultaneously . Streaming and Message
Modes as defined for AAL 3/4 and AAL5
are supported.
In Message Mode, the Convergence
Sublayer payload (Service Data Unit) is
considered to be the user data
transmitted from or received into a single
entity. A single entity being regarded as
one user data buffer or linked chain of
user data buffers.
In Streaming Mode, the Convergence
Sublayer payload is considered to be the
user data transmitted from or received
into multiple entities separated in time.
This allows a partial segmentation or
reassembly. In Streaming Mode the
chaining of buffers is not supported.
The ALC Device supports two
transparent modes. In transparent
payload mode the 48 byte ATM cell
payload is received or transmitted
transparently into or from SAR Memory.
In transparent cell mode the ATM cell is
received or transmitted transparently into
or from SAR Memory.
Edition 2.0MB86687A
2
System Configurations
In adaptor card applications, the ALC
interfaces to the Fujitsu MB86683
Network Termination Controller Device
(NTC) (or compatible CCITT I.432
device) via a full duplex 8-bit wide
UTOPIA compliant cell stream interface
for connection to the transmission
medium.
In Hub or Router applications, the ALC
connects directly to the Fujitsu MB86680
Self-routing Switch Element (SRE) for
autonomous routing. In this case a
programmable Tag of 3 bytes must be
appended to each cell.
Alternatively, it may be connected to a
proprietary backplane architecture. To
support this application the ALC can be
configured to transmit and receive ATM
cells with a four byte header minus the
HEC field.
Fig. 1 – Possible System Configurations
Host
CPU
Host
CPU
SAR
Memory
System
Memory
ALC
ALC NTC
or
SRE
NTC
or
SRE
Host
CPU
System
Memory ALC NTC
or
SRE
SAR
Memory
ÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉ
Edition 2.0 MB86687A
3
2. EXTERNAL INTERFACES
2.1 Logical Outline
A logical view of the ALC’s external pins is illustrated in Fig. 2, and a physical pin
assignment is shown in Appendix F.
SRD0–SRD31
SRA2–SRA23
ALC
D0–D15
TXD0–TXD7
TXSOC
TXCLK
RXD0–RXD7
RXSOC
RXCLK
DCCK
TIN
TOUT
IRQ RD WR
BGACK
DTACK / READY / BERR
HOLD / BR
HLDA / BG
MRD / AS / ADS / TS
MWR / R/W / R/W
DS / BLAST / TIP
RXEN
RESET
Fig. 2 – ALC External Interfaces
CSA1–A6
SAR
Memory
Interface
Cell
Stream
Interface
Microprocessor
Interface
TXEN
TDI TCKTDO TMS
JTAG Test Port
TOCS
TDCS
ROCS
RDCS
TXDRV
SADRV
BE0 / A0
BE1 / A1
BE2 / SIZ0
BE3 / SIZ1
TXFULL
RXEMPTY
PRTY0–PRTY3
Edition 2.0MB86687A
4
2.2 Detailed Description
2.2.1 SAR Memory Interface
This interface provides the ALC DMA
controller with access to external dual
port memory or shared access to system
memory.
The interface comprises the following
signals:
SRD0 – SRD31
Bi–directional SAR memory data bus.
PRTY0 – PRTY3
Bi–directional SAR memory data bus
parity protection.
SRA2 – SRA23
Most significant 22 bits of the SAR
memory address bus. All bits are tri-state
outputs.
SADRV
This input allows the SAR memory
interface to be permanently driven.
BE0 / SRA0
Multifunction tri-state output. Functions
are as follows:
Intel mode: BE0
Byte Enable 0
Enables data byte on SRD0 – SRD7,
Motorola mode: SRA0
SAR Memory Address bus bit 0.
BE1 / SRA1
Multifunction tri-state output. Functions
are as follows:
Intel mode: BE1
Byte Enable 1
Enables data byte on SRD8 – SRD15.
Motorola mode: SRA1
SAR Memory Address bus bit 1.
BE2 / SIZ0
Multifunction tri-state output. Functions
are as follows:
Intel mode: BE2
Byte Enable 2
Enables data byte on
SRD16 – SRD23.
Motorola mode: SIZ0.
BE3 / SIZ1
Multifunction tri-state output. Functions
are as follows:
Intel mode:
BE3: Byte Enable 3
Enables data byte on
SRD24 – SRD31,
Motorola mode: SIZ1.
The coding of the SIZ signals has the
following meaning:
SIZ1 SIZ0 Meaning
0 1 Burst of 8
1 0 Word
1 1 Burst of 4
0 0 Long Word
MRD / AS / ADS / TS
Bi-function tri-state bi-directional signal.
SAR memory read signal (Intel mode),
SAR memory address strobe (Motorola
mode). This signal is used as an input
during Motorola mode bus arbitration
and is the ADS signal in extended modes.
In extended modes for Intel, it is ADS and
Motorola (TS).
Edition 2.0 MB86687A
5
MWR / R/W/ R/W
Multifunction tri-state output. SAR
Memory write signal (Intel mode), SAR
Memory read/write signal (Motorola
modes) and read/write (Intel Extended
mode).
DS / BLAST / TIP
Multifunction tri-state output. Data Strobe
in Motorola mode; BLAST (last in burst) in
Intel extended mode; TIP (transmission
in progress) in extended Motorola mode.
TOCS
Transmit Overhead Cycle Start output.
This is asserted before any transmit cycle
that is not a data cycle.
TDCS
T ransmit Data Cycle Start output. This is
asserted before a transmit data cycle.
ROCS
Receive Overhead Cycle Start output.
This is asserted before any receive cycle
that is not a data cycle.
RDCS
Receive Data Cycle Start output. This is
asserted before a receive data cycle.
HOLD / BR
Tri-state Hold/Bus request output used to
request bus access for ALC DMA
controller.
HLDA / BG
Hold/Bus Grant input used to pass
control of the bus to the ALC DMA
controller.
BGACK
Bus Grant Acknowledge output indicates
ALC DMA controller is assuming control
of the bus.
READY / DTACK / BERR
Ready/Data Transfer Acknowledge
input. In standard mode used to
terminate DMA / DPR cycles. In FAST
mode used to generate an ALC interrupt
indicating memory access conflict (Bus
error).
DCCK, DMA CYCLE CLOCK
Clock input used to drive the ALC DMA
cycles.
2.2.2 Microprocessor Interface
The microprocessor interface comprises
the following signals:
A1–A6
Microprocessor address bus inputs.
DATA0–DATA15
Bi-directional microprocessor data bus
signals DATA 0–15.
CS
Microprocessor bus chip select input.
RD
Microprocessor bus read input.
WR
Microprocessor bus write input.
IRQ
Interrupt request output.
RESET
ALC master reset input.
Edition 2.0MB86687A
6
2.2.3 Cell Stream Interface
This interface comprises the following
signals:
TXD0–TXD7
These tri–state output signals provide 8
bit parallel transmit data which is cell
aligned and asynchronous. To enable
daisy chaining of ALCs these signals are
tri-state.
TXSOC
Transmit start of cell sync output. This tri
–state output indicates that the first byte
of an ATM cell or routing tag is available
on the TXD0 – TXD7 data lines. The
frequency of this signal depends on the
cell transmission rate from the ALC. To
enable daisy chaining this pin is tri-state.
TXCLK
This input signal is used to clock transmit
data out of the ALC. The signal can be of
arbitrary frequency but should be
sufficient to support the bandwidth
specified by the ALC traffic shaping
parameters. No phase relationship is
assumed with RXCLK.
TXEN
This tri–state output signal is asserted in
UTOPIA mode when the cell stream
transmit is outputting valid data.
TXFULL
This input is used in UTOPIA mode to halt
the ALC transmit cell stream data.
RXD0–RXD7
These 8 input pins provide the ALC with 8
bit parallel, cell aligned receive data.
RXSOC
Receive start of cell sync input. This
signal indicates when the first byte of an
ATM cell or routing tag is available on the
RXD0 – RXD 7 pins.
RXCLK
This input signal is used to clock received
data into the ALC. No phase relationship
is assumed with TXCLK.
RXEN
This output signal is used in UTOPIA
mode to control the flow of receive cells
when using an external FIFO. The signal
indicates that the ALC receive buffers are
full.
RXEMPTY
This input signal is used to control the
flow of receive cells when using an
external FIFO. The signal indicates that
the FIFO is empty.
TOUT
Token out output. This signal is used to
enable daisy chaining. The ALC
transmits a ‘token’ pulse on the falling
edge of TXCLK to indicate that it has
completed a cell transfer or has no data
to transmit. The output is held low during
cell transmission.
TIN
Token In input. This input should be wired
to the TOUT output of other ALC devices
to form a daisy chain. If unused this pin
should be pulled high.
TXDRV
This input allows the ALC to permanently
drive the transmit cell stream interface
Edition 2.0 MB86687A
7
2.2.4 JTAG Test Port
TCK
JTAG test clock input
TMS
JTAG test mode input
TDI
JTAG test data input
TDO
JTAG test data output
SIGNAL PULL VALUE COMMENT
The following are essential for correct operation
BGACK High 2K7 DMA mode
High 10K Dual Port Memory mode
IRQ High 2K7
TXSOC Low 10K Only when TXDRV is not asserted
TXEN High 10K Only when TXDRV is not asserted
HOLD/BR Low 2K7 Only in Intel DMA mode
High 2K7 Only in Motorola DMA mode
MRD/AS High 10K DMA mode *
High 100K Dual Port Memory mode
HLDA/BG High 10K
DS High 100K
The following are not essential, but are advisable
TXD0–7 High/Low 100K Only when TXDRV is not asserted
SRD0–31 High 100K Only when SADRV is not asserted
The following can be omitted if the data bus can be guaranteed not to float
between 2.2v and 0.8v.
MWR/R/W High 100K *
BE0/A0 High 100K *
BE1/A1 High 100K *
BE2/SIZ0 High 100K *
BE3/SIZ1 High 100K *
A2–21 High 100K *
Note: * – These signals are continuously driven when Dual Port Ram mode is selected
or SADRV is asserted.
Table 1 – Pull Values
Edition 2.0MB86687A
8
3. FUNCTIONAL DESCRIPTION
This section describes the behaviour of
each major functional block within the
ALC, as illustrated in Fig. 3. The
descriptions in this section are from a
user’s perspective and are intended to
give a detailed description of device
functionality and modes of operation.
The ALC comprises the following major
components:
High Speed DMA Controller,
Traffic Management Controller,
Transmit and Receive Buffers,
Segmentation and Convergence
Sub-layer Controller,
Reassembly and Convergence
Sub-layer Controller,
Cell Stream Interface,
Microprocessor Interface,
Segmentation and Reassembly
Memory Interface.
Fig. 3 – ALC Block Diagram
SAR
Memory
Interface
High
Speed
DMA
Controller
Traffic Management
Controller
ALC Internal Registers
Cell
Stream
Interface
Cell
Stream Interface
Processor Interface
ATM
Cell
Transmitter
Transmit
Buffer
( 3 Cells )
Receive
Buffer
( 2 Cells )
Segmentation &
Convergence
Sub-layer
Controller
Reassembly and
Convergence
Sub-layer
Controller
ATM
Cell
Receiver
VCI Status/
Descriptor
Table
Edition 2.0 MB86687A
9
3.1 DMA Controller and SAR Memory Interface
3.1.1 General
The ALC contains an intelligent DMA
Controller to manage the segmentation
and reassembly of user data packets
using the minimum of host processor
intervention. Communication with the
host processor is mainly through shared
data structures in either dual port or
system memory.
The system implications of a dual port or
system memory approach are largely
performance related.
3.1.2 Shared Data Structures
The shared data structures used to
control the segmentation and
reassembly of user data are shown in
Fig. 4 on page 10. The transmit side is
controlled via the Transmit Pending
Queue, the Transmit Descriptor Table,
the Circuit Reference Table and the
Transmit Buffer Release Queue. The
ALC uses reserved fields in the T ransmit
Descriptor to compose peak rate queues
for segmentation at the specified peak
rate and for leaky bucket averaging. The
host can program up to 12 peak rates for
the ALC.
The receive side is controlled by the
Receive Buffer Free Queue, the Receive
Descriptor Table and the Receive Buffer
Ready Queue. In addition the DMA
Controller uses an internal RAM table,
the Receive Status / Descriptor Table to
store receive VCI status and descriptor
identifiers. The purpose of each of these
tables is described below.
3.1.3 Transmit Data Structures
The host writes commands to the
Transmit Pending Queue to instruct the
ALC to queue a data packet for
segmentation. The packet can be
queued for transmission on one of 12
peak rate queues. Each Transmit
Pending Queue entry contains a pointer
to a Transmit Descriptor in the Transmit
Descriptor Table.
The Transmit Descriptor Table is
composed of up to 4096 descriptors.
Each descriptor contains a pointer to
data for segmentation. The reserved
fields in the Transmit Descriptor are used
by the ALC to construct queues of
transmit packets for each selected peak
rate. The Transmit Descriptor also
contains a pointer to an entry in the
Circuit Reference Table (CRT).
The CRT is composed of up to 1024
entries, one entry for each active Virtual
Circuit. Each entry contains fields for the
ATM cell header, an optional routing tag,
and the leaky bucket parameters for the
virtual circuit. The ALC reads the cell
header and the leaky bucket parameters
from the CRT each time a cell is
segmented from a transmit buffer.
Management of the Peak Rate
segmentation queues is handled
autonomously by the ALC. The only host
intervention required is on a per packet
basis. To queue a packet the host
constructs the relevant descriptor and
writes the pointer to the descriptor into
the Transmit Pending Queue. Transmit
descriptors are recovered by the host by
reading the Transmit Buffer Release
Queue.
Edition 2.0MB86687A
10
Fig. 4 – Shared Data Structures
CR = b CR = b
ALC
QUEUE H1
QUEUE H2
QUEUE L3
QUEUE L4
CR = z
Packets Queued
For Segmentation
At Peak Service
Rate H1
Packets Queued
For Segmentation
At Peak Service
SAR MEMORY
Rate L4
CR = x
CIRCUIT REFERENCE TABLE TRANSMIT PENDING QUEUE
RECEIVE VCI STATUS TABLE
DMA
ALC
SEGMENTING WAITING
SEGMENTING WAITING
ENTRY 0
ENTRY 1023
HOST WRITE
ALC READ
ADDRESS
DATA
CR = Circuit Reference
ENTRY 0
1023
TRANSMIT DESCRIPTOR TABLE
TRANSMIT BUFFER
RECEIVE BUFFER READY QUEUE RECEIVE BUFFER FREE QUEUE
HOST WRITE
ALC READ
ENTRY 0
1023
RECEIVE DESCRIPTOR TABLE
RECEIVE BUFFER
Private ALC working space
for Peak Rate Management
and Leaky Bucket Averaging
ALC WRITE
HOST READ
TX BUFFER RELEASE QUEUE
CR = a
CR = n
CR = x
CR = z
ALC WRITE
HOST READ
Edition 2.0 MB86687A
11
After a packet has been transmitted, the
ALC will return the Transmit Descriptor
used to the host via the Transmit Buffer
Release Queue. Each entry in this queue
contains a pointer to the relevant
descriptor in the Transmit Descriptor
Table.
3.1.4 Receive Data Structures
At the start of reassembly for each new
packet the ALC finds a new Receive
Descriptor (RD) by reading the Receive
Buffer Free Queue. Each entry contains a
pointer to a RD in the Receive Descriptor
Table.
The Receive Descriptor Table is
composed of up to 4096 RDs. Each RD
contains a pointer to a receive buffer . The
RD also contains fields to support receive
buffer chaining and the received VCI or
MID fields. A reserved field in the RD is
used by the ALC to support a receive
buffer ageing timeout.
After reception is complete, the ALC
passes the receive descriptor to the host
using the Receive Buffer Ready Queue.
Each entry in the queue contains a
pointer to the appropriate RD and the
status of the receive buffer.
A more detailed description of the shared
data structures is provided in Section 4,
Developers Notes, of this datasheet.
3.1.5 Packet Segmentation
The DMA Controller is responsible for
linking transmit descriptors into one of
the 12 service rate queues. The queues
are composed of a linked list of TDs. The
structure of each of the service rate
queues is shown in Fig. 5.
When the ALC reads a transmit packet
command from the Transmit Pending
Queue, it links the packet into the service
rate queue specified in the appropriate
Circuit Reference Table entry (see
Fig. 20 on page 36).
VCI = N VCI = N VCI = N
VCI = L VCI = L
VCI = M
Fig. 5 – Transmit Queue Structure
Vertical
Queue
(Different
VCs)
Horizontal
Queue
(Same VCs)
Edition 2.0MB86687A
12
Packets with the same circuit reference,
ie same VPI/VCI or MID are queued
horizontally. Packets with different circuit
references for transmission on the same
service rate queue are queued vertically.
Horizontally queued packets will be
serviced when the packet at the front of
the queue is completed.
Each service rate queue is serviced
vertically at the specified peak rate under
the control of the Traffic Management
Controller. A queue entry has been
serviced when a complete SAR–PDU
payload of either 44 or 48 bytes has been
read from the packet. The queue has
been serviced when each queue entry
linked vertically has been serviced.
Message Mode Operation
In Message Mode, the user data buffer
associated with a Transmit Descriptor will
contain the full CS–PDU payload to
which the CS–PDU header and trailer will
be added to terminate the protocol.
Alternatively, the CS–PDU payload may
be spread across several user data
buffers when the host passes a chain of
TDs to the ALC. The CS–PDU header will
be added to the first user data buffer in
the chain. The ALC will work through the
chain until the CHAIN END bit is cleared
(CE = 0) and then the CS–PDU trailer will
be added.
Streaming Mode Operation
In Streaming Mode, a partial
segmentation can be accomplished. This
allows the user data unit to be partially
received into SAR memory and for
segmentation to commence before the
whole unit is received.
Table 2 describes single buffer, chaining
and streaming modes for the ALC. It
should be noted that the transmit and
receive sides work independently.
Transmit operation is controlled by the
Transmit Descriptor on a packet by
packet basis. The whole receive side is
controlled by Control Register17 (see
Fig. 43 in Appendix B.).
3.1.6 Packet Reassembly
The DMA Controller maintains the status
of each receive connection using the
internal Receive Descriptor / Status
table. This table is accessible to the host
for initialisation purposes, diagnostics
and support for scatter/gather mode.
The host must activate each connection
using the host access registers 57 to 59
(Fig. 58 & Fig. 59). The AAL type and
ACT bits must be initialised to the
required value.
Message Mode Operation
In Message Mode, the user data buffer
associated with a Receive Descriptor will
contain the full reassembled CS–PDU
payload.
If the size of this payload exceeds the
buffer size the buffer will be returned to
the host with a buffer overflow indication.
Alternatively, the CS–PDU payload may
be spread across several user data
buffers when the host programs the ALC
for receive buffer chaining operation. The
head of the chain of buffers will be passed
back to the host when the end of
message is received.
Edition 2.0 MB86687A
13
Streaming Mode Operation (PR)
The size of the CS–PDU payload may be
much greater than the size of one receive
data buffer. In addition, the memory
resource as a whole may be limited or the
user may require that sections of the
CS–PDU be forwarded to the host as
soon as they fill each buffer.
This partial reassembly is accomplished
by programming the ALC for streaming
mode operation.
Buffer Chaining is not possible when the
streaming mode register bit has been
programmed.
MESSAGE MODE STREAMING MODE
OPERATION DIR SINGLE BUFFER CHAINING
Queue
Packet Tx M=0, CS=0, CE=0
Whole packet in
single buffer
M=0
CS 1st buffer=0
CS other buffers=1
CE last buffer=0
CE other buffers=1
M=1, CS=0 in first
buffer
CE=0
Add buffers
via TPQ
*
Tx NA NA M=1 in extra buffers
M=0 in last buffer
CE=0
Release
buffer Tx When packet Tx
complete Released on a buffer
by buffer basis
(–> TRBQ)
Released on a buffer
by buffer basis
(–> TRBQ)
Start
Re-assembly Rx BCHAIN=O,
SMODE=O
Get next BFQ entry
BCHAIN=1,
SMODE=0
Get next BFQ entry
BCHAIN=O,
SMODE=1
Get next BFQ entry
Buffer full Rx Error buffer overflow Get next BFQ entry
Link buffers Get next BFQ entry
Release buffer to
host (–> RBRQ)
Packet
complete Rx Release buffer to
host Release first buffer
to host (–> RBRQ)
**
Release buffer to
host (–> RBRQ)
Notes:
* In Transmit Streaming mode the host must queue all current packet buffers on any given
circuit before starting a new packet.
** In Receive Chaining the host will be given the descriptor reference of the first buffer in
the chain. The host must follow the chain until the condition V=0 is set in the descriptor.
Table 2 – Single Buffer, Chaining and Streaming Modes
Edition 2.0MB86687A
14
Buffer Ageing Support
Buffer Ageing support is programmed by
setting bit D12 (BAS) in Register 17. If
set, upon reassembling the first cell of a
packet, the ALC stamps a time base in
the RD.
On reassembly of further cells for the
same packet, the ALC compares the time
elapsed against the value programmed
in Register 52 – Receive Buffer Timeout
Counter Register.
If the difference is greater than the value
in this register, the RD is returned to the
Buffer Ready Queue with a code ‘1100’
indicating Buffer Timed Out –
Reassembly Aborted. The rest of the
packet will be discarded by the ALC.
For a greater time range, Register 51 –
Receive Buffer Timeout Counter Period
Register – can be programmed. This
scales the DCCK used to increment the
time base counter . For example, a DCCK
at 25MHz provides a time range up to 170
seconds.
Buffer Ageing Support is only available in
Message Non–Chaining mode.
Maximum Packet Length
At the start of cell reassembly, the ALC
compares the value of Bytes Received
accumulated in the RD with the value
programmed in Register 54 – Maximum
Received Packet length Register.
If the register value is exceeded, the ALC
writes out the RD to the Buffer Ready
Queue with a code ‘1001’ indicating
Receive Maximum Length Exceeded.
For Message Chaining mode, the ALC
compares the accumulated value of
Bytes Received to date across the chain
at the moment of adding a further RD to
the chain.
Maximum Packet Length checking is not
supported in Streaming mode.
Edition 2.0 MB86687A
15
3.2 Traffic Management Controller
The Traffic Management Controller is
responsible for the following functions:
Initiate periodic packet segmentation
from one of the 12 Peak Rate Queues
at intervals specified in the Queue
Service Rate registers. The queues
are grouped into three priority
classes: high, medium and low , with 4
queues in each priority class.
Manage total ALC peak transmission
rate. If the total peak transmission rate
exceeds a specified threshold, the
traffic management controller will
service the queues according to their
priority until the total peak rate falls
below the threshold. This feature can
be used to ensure that the ALC will not
exceed the negotiated quality of
service for the overall link connection.
Manage average rate shaping of
transmit traffic on a per virtual circuit
basis using the leaky bucket
algorithm. The leaky bucket
parameters for this are supplied from
the Circuit Reference Table
referenced in the Transmit Descriptor.
Manage average rate shaping on the
total ALC transmission according to
the leaky bucket algorithm. The leaky
bucket parameters for this averaging
are determined by the ALC Peak Cell
Transmission and ALC Average Cell
Transmission registers. This feature
is also used to ensure that the ALC will
not exceed the quality of service for
the overall connection.
3.2.1 Peak Rate Queue Service
Requests
The ALC peak rate queue service control
logic is responsible for requesting the
transmission of cells queued to the peak
rate queues on a per virtual circuit basis.
Twelve programmable counters are used
to specify the peak transmission rate for
each queue.
The twelve counter values are
programmed using the Queue Service
Rate Registers and enabled using the
Queue Enable Registers. The counter is
clock TXCLK (for TXCLK period, see
Appendix C.) which can be pre-scaled to
increase it’s dynamic range. The peak
service rate value is used to determine
the frequency of access to the respective
peak rate queue. Each time the queue is
accessed one cell may be transmitted for
each queued entry (one per VC) if a leaky
bucket token is available for that queue
entry.
Each Circuit Reference Table contains a
sub rate select field which can be used to
further reduce the peak cell transmission
rate to 50% or 25% of the nominal peak
rate specified in the Queue Service Rate
Register. This gives a total available
range of 32 effective peak transmission
rates for entries of each peak rate queue.
3.2.2 Total ALC Peak Rate Control
The ALC contains link capacity control
logic which is used to ensure that the
overall ALC link transmission rate does
not exceed a pre-programmed value as
specified in the ALC Peak Cell
Transmission Rate register.
Edition 2.0MB86687A
16
If the overall required transmission rate
exceeds this programmed value, the link
capacity controller will mask the lower
priority queues. This will cause cell
transmission to cease on the low priority
queues until the overall peak rate falls
below the programmed total ALC value.
Note that the queues are masked in the
following priority: All four L queues
followed by all four M queues.
3.2.3 Per VC Leaky Bucket Traffic
Shaping
The leaky bucket algorithm is used to
shape the transmit data characteristics
on a per virtual circuit basis by controlling
the average rate of cell transmission and
the length of each burst of cells
generated. The leaky bucket parameters
are determined by the values in the
Circuit Reference Table for each active
VC. (See section 3.1.3, Transmit Data
Structures).
The parameters relevant to leaky bucket
management are the user
programmable parameters, Bucket
Capacity , M and the Bucket Utilization, U.
The bucket capacity is used to calculate
the maximum sustained burst of cells at
the specified peak rate. The average rate
of emptying the bucket is derived from
the utilisation.
The utilisation is expressed as a fraction
of the peak rate. See section 4 on ALC
configuration and control for full details.
Two modes of operation are supported:
single leaky bucket mode and double
leaky bucket mode.
In single leaky bucket mode, cells are
transmitted in an initial burst as defined
by M at the specified peak rate. The burst
length may exceed the bucket capacity
since tokens are added to the bucket at
the same time as tokens are removed.
Subsequent cells are transmitted at the
average rate as tokens are added to the
bucket.
In double leaky bucket mode, cell
transmission will only occur in bursts at
the peak rate when the bucket
associated with that VC is full of tokens.
3.2.4 Total ALC Leaky Bucket
Traffic Shaping
In addition to the traffic shaping applied to
the traffic transmitted from each virtual
circuit the ALC can manage both the
peak and average transmission rate on
the total ALC output traffic.
A total ALC Leaky bucket size is defined
in the ALC Leaky Bucket Capacity
Register. This capacity value is used in
conjunction with the leaky bucket
utilization to limit the ALC output burst
length. The total ALC utilisation value is
derived from the ALC Peak Cell Rate and
ALC Average Cell Rate Register
contents.
Edition 2.0 MB86687A
17
3.3 Segmentation and Convergence Sub-layer Controller
This block is responsible for managing
the transmission of cells according to the
specified Adaptation Layer protocol:
AAL3/4 or AAL5.
3.3.1 SAR Sub-layer functions
Fig. 6 shows the format of SAR Protocol
Data Units (SAR–PDU ) for AAL types 3/4
and 5. The following protocol actions are
performed on each SAR–PDU for AAL 3/4:
Preservation of SAR service data unit
integrity through generation of the
segment type field,
Error Protection through Sequence
Number and CRC generation,
Multiplexing/Demultiplexing using the
Multiplexing ID,
Support of the Abort function.
The fields of AAL T ype 3/4 are detailed in
the following text.
ST, Segment Type
The first SAR–PDU generated from a
user data packet carries the Beginning of
Message (BOM) code 10. Subsequent
SAR–PDUs carries the Continuation Of
Message (COM) code 00.
The final SAR–PDU carries the End of
Message (EOM) code 01. SAR–PDUs
which carry entire SAR–SDUs such as
those defined for signalling carry the
Single Segment Message (SSM) code 1 1.
SN, Sequence Number
The four bits of this field are used for
modulo 16 numbering of each
SAR–PDU. The Sequence Number is set
to zero at the start of each SAR–SDU.
MID, Multiplexing Identification
This field is used for multiplexing multiple
CS–PDU (Convergence Sub-layer
Protocol Data Units) connections on a
single ATM layer connection. When MID
mode is selected, this field carries the
MID specified in the Circuit Reference
Table. The MID field is set to zero when
multiplexing is not used.
ST SN MID SAR–PDU Payload LI CRC
SAR–PDU
CELL HEADER
CELL HEADER
(a)
(b)
Fig. 6 – ATM Protocol Data Units (a) AAL3/4 (b) AAL5
SAR–PDU Header SAR–PDU Trailer
52
bits 4
bits 10 44 bytes 6
bits 10
bits
5 bytes 48 bytes
bytes bits
Edition 2.0MB86687A
18
LI, Length Indicator
This field indicates the number of bytes
contained in the SAR–PDU. The
SAR–SDU bytes are left justified within
the SAR–PDU payload field and
remaining bytes will be set to 0.
CRC, Cyclic Redundancy Check
This field contains the 10 bit CRC code. It
is calculated (as defined in CCITT I.363
for AAL3/4) over the SAR–PDU including
header, trailer, payload and length
indication.
3.3.2 Convergence Sub-layer
Functions
Fig. 7, below , shows how the user data is
formatted in the convergence sub-layer
before segmentation. The ALC maintains
internal tables to manage AAL3/4
sequence numbers and AAL5 CRC
results.
The fields of the CS–PDU header and
trailer are listed and described on the
following pages.
CRC 32LENGTH
CONTROL
FIELD
PADCS–PDU Payload
(b) AAL5
(a) AAL3/4
4 bytes2 bytes2 bytes0–47 bytes
CS–PDU trailer
CPI Btag BASize PAD AL Etag LENGTHCS–PDU Payload
CS–PDU trailerCS–PDU header
0–3 2 2
Fig. 7 – Convergence Sub-layer Protocol Data Units
11bytesbytebyte 0 – 64k bytes bytes 11
byte byte
1bytes
0 – 64k bytes
CPCS–UU CPI
CPCS–UU: CPCS User to User Indication
CPI: Common Part Identifier
Length: Length of CPCS–SDU
CRC: Cyclic Redundancy Check
CPI: Common Part Identifier
Btag Beginning Tag
BASize Buffer Allocation Size
AL Alignment
Etag End Tag
Edition 2.0 MB86687A
19
AAL 3/4 HEADER AND TRAILER
CPI, Common Part Identifier
This field is coded to all zeros to indicate
that the values in BASize and Length
Fields are measured as unit multiples of
bytes.
BTAG, ETAG, Beginning & End Tags
These Fields are given the same modulo
256 value for each CS–PDU and
incremented on successive CS–PDUs.
The receiver will check that they are the
same value on a CS–PDU to CS–PDU
basis but will not check for
incrementation over successive
CS–PDUs.
BASize, Buffer Allocation Size
This value will be the size of the CS–PDU
payload when Message Mode Service is
being run. In Streaming Mode this value
may be greater than or equal to the
CS–PDU payload size. Its purpose is to
inform the receiving entity of the buffering
required to accommodate the
transmitted data.
AL, Alignment
No information is conveyed by this field. It
merely provides 32 bit alignment in the
CS–PDU trailer. The Pad field has the
effect of making the CS–PDU an integral
multiple of 4 bytes.
Length
Length of CS–PDU payload.
PAD, Padding Field
This field complements the CPCS–PDU
to an integral multiple of 4 bytes and
conveys no information.
AAL 5 TRAILER
For AAL 5 the CS–PDU has no header.
The trailer is derived from the data
structure and the 32 bit CRC stored in the
convergence sub-layer table. The fields
of the CS–PDU trailer are listed below.
PAD, Padding Field
The purpose of the PAD bytes is to align
the CS–PDU trailer into the last 8 bytes of
a SAR–PDU. If this calculation results in
the transmission of an extra cell it is not
transmitted back to back with the
previous SAR–PDU, as this would
compromise the transmission rate and
the Traffic Management Controller
parameters.
Control Field
The Control Field comprises 2 fields
shown in Fig. 7. These fields are:
CPCS–UU
This field is used to transparently
transfer CPCS user to user
information.
CPI
This field is used to align the
CPCS_PDU to 64 bits and should be
coded as zero.
Length
Length of CS–PDU payload.
CRC, Cyclic Redundancy Check
The CRC field is filled with the value of a
CRC calculation (as defined in CCITT
I.363 for AAL 5) which is performed over
the entire contents of the CS–PDU. This
includes the payload, the PAD field, and
the first four bytes of the trailer . The initial
CRC remainder is preset to all ones
before generation and checking.
Edition 2.0MB86687A
20
3.3.3 Error Recovery & Notification
The ALC provides provisions for sending
SAR–U–ABORT ATM Cells in streaming
mode in accordance with the selected
protocol. In accordance with AAL5
protocol the ABORT SAR–PDU is
defined as SDU=1, LENGTH FIELD
coded to zero and CRC32 correct. In
accordance with AAL3/4 protocol the
ABORT SAR–PDU is defined by ST=
EOM, payload coded to zero, and LI = 63.
The CRC–10 and MID field must be valid.
3.3.4 Transparent Modes
Transparent Cell Mode
In this mode the host provides cells of 52
bytes (4 header and 48 data) in a
transmit descriptor to the transmit
pending queue. The transmit side
generates and includes the HEC byte (if
mode register 17 bit D9 = 0) and
transmits the resulting 53 byte cell with an
optional CRC10 included otherwise no
further protocol carried out.
On receiving a transparent cell the
receive side checks and removes the
HEC byte before loading the remaining
52 bytes into the internal receive buffer.
The receive side DMA then obtains a
descriptor from the buffer free queue,
writes all 52 bytes into the buffer and then
writes out the descriptor to the buffer
ready queue.
Note that the only updated field within the
receive descriptor is the VCI field (the
bytes received is not updated as it is
always 52).
Transparent Payload Mode
In this mode the host provides a multiple
of 48 bytes of cell payload data within a
single transmit descriptor to the transmit
pending queue. The header information
is obtained from the Circuit reference
table, a HEC byte is generated (if mode
register 17, bit 9 = 0) and the cell is
transmitted. As with transparent cell
mode, apart from including an optional
CRC10, no further protocol is performed.
The receive operation is also similar to
transparent cell mode but with only the 48
payload bytes being transfered by DMA
to SAR memory. The CRC 10 can be
checked if the cell is detected to be an
OAM or Resource management cell.
Edition 2.0 MB86687A
21
3.4 Reassembly and Convergence Sub-layer Controller
This block is responsible for managing
the reception of cells according to the
specified Adaptation Layer protocol:
AAL3/4 or AAL5.
The following adaptation layer functions
are performed on a SAR–PDU basis:
Preservation of SAR service data unit.
Checking the Segment Type Field,
Error Detection and Handling.
CRC and Sequence Number
Integrity Checking,
Multiplexing / Demultiplexing using
the MID field,
Support of the Abort Function.
The following adaptation layer functions
are performed on a CS–PDU basis:
Detection of BTag, ETag fields,
Detection of Incorrect Length Field,
Detection of Alignment errors,
Detection of errors using CRC 32
calculation.
Fig. 8 – Cell Stream Interface
Tag
(0–3 bytes) ATM Cell (52 or 53 bytes) Tag
(0–3 bytes)
52 to 56 clock cycles idle period
(n clock cycles,
n > or = 0)
TXD[0–7]
TXSOC
TXCLK
Tag
(0–3 bytes) ATM Cell (52 or 53 bytes) Tag
(0–3 bytes)
52 to 56 clock cycles idle period
(m clock cycles,
n > or = 0)
RXD[0–7]
RXSOC
RXCLK
Edition 2.0MB86687A
22
3.5 Cell Stream Interface
The Cell Stream Interface will transmit
and receive an asynchronous stream of
ATM cells. Cells will be transmitted and
received in 8-bit parallel form with
separate synchronisation signals used to
identify the start of a cell.
The ALC cell stream interface may be
required to operate in one of two
environments either in a Switch Device or
a Termination Device.
3.5.1 Termination Device
Operation
In termination device operation the ALC
is intended to connect to the Fujitsu
MB86683 Network Termination
Controller or equivalent device for
physical media interfacing. Cells are
transmitted and received header to trailer
or with an idle period between each cell,
see Fig. 8.
The idle period may be of any number of
clock cycles including zero. There is no
relationship between the transmit and
receive sync pulses.
3.5.2 Switch Device Operation
In switch device operation, for example in
hub and router applications, the ALC can
be connected directly to an ATM switch
fabric port such as the Fujitsu MB86680
Self–routing A TM Switch Element, or to a
proprietary backplane structure.
In this environment the ALC will append a
programmable routing Tag of up to 3
bytes to the start of each cell. In the
receive direction the Tag is removed
before protocol processing of the cell
commences. In addition, the HEC field
can optionally be omitted resulting in a 52
byte cell. Switch Device timing is also
shown in Fig. 8.
3.5.3 Cell Stream and UTOPIA
The Fujitsu Cell Stream mode has been
superceded by the UTOPIA specification
from the A TM Forum, but is still supported
for backward compatibilty. The mode
selection is performed by tying the CS/UT
pin high or low as required. By default,
Fujitsu cell stream is selected by an
internal pull–up resistor.
3.5.4 Utopia Flow Control
Forward and backward byte-level flow
control is supported in both directions.
The forward flow control signal indicates
the validity of the current data. The
backward flow control signal indicates
whether data will be accepted in a
particular cycle. Neither flow control
signal is directly qualified by the other :
they can change state independently.
Unused flow control inputs should be tied
off to their active levels. All signals are
transmitted and sampled on the rising
edge of the clock.
Timings for UTOPIA are illustrated in
Fig. 10 and Fig. 11. Note that all of the
flow control signals can change state
independently.
Edition 2.0 MB86687A
23
3.5.5 Cell Stream Flow Control
In Cell Stream mode the ALC will provide
an indication that its receive buffer is full
by using the RXEN output signal as
shown in Fig. 9. The other flow control
signals are not supported in Cell Stream
mode.
Unused flow control inputs should be tied
off to their active levels.
3.5.6 Loopback
When loopback is enabled (by setting the
TSTLP bit in CR16) the transmit data is
internally looped back into the receive
path. For this operation TXCLK must be
present but RXCLK need not be. The
transmit data will still appear on the
transmit interface. Flow control is
handled in loopback only in UTOPIA
mode.
Fig. 9 – Cell Stream Receive Interface Timing
RXCLK
RXEN
RXD0–7
RXSOC
Fig. 10 – UTOPIA Transmit Interface Timing
TXCLK
TXFULL
TXD0–7
TXSOC
TXEN
Invalid Invalid
Fig. 11 – UTOPIA Receive Interface Timing
RXCLK
RXEMPTY
RXEN
RXD0–7
RXSOC Invalid
Invalid
Invalid
Invalid
Invalid
Edition 2.0MB86687A
24
3.5.7 Transmit Multiplex
Operations
A token passing mechanism is used
when more than one ALC share the same
cell stream interface. In this case the ALC
should be wired in a daisy chain
configuration using the TIN (Token In)
and TOUT (Token Out). This mechanism
is illustrated in Fig. 12.
TIN should be connected to the TOUT
output of an ALC higher up the daisy
chain. When the TIN input is inactive
(low), the ALC stops transmitting data
and places its TXD and TSN pins in high
impedance.
The ALC will transmit a Token pulse, on
TOUT, on the falling edge of TXCLK to
indicate that it has completed a cell
transfer or that it has no data to transmit.
Note that if one ALC is able to transmit
cells continuously on this interface (ie. no
gaps between cells) TOUT will only pulse
at the end of a cell if TIN is inactive one
clock period before the last byte in the
cell.
Fig. 12 – CSI Token In/Out Timing
Byte 52 Byte 53
TXD
TXCLK
TOUT
TXCLK
TXD
TIN (TOUT
ALC2)
TOUT
TXSOC
TOUT timing at the end of a Cell
TIN timing at the start of a Cell (2 ALCs Daisy Chained)
Byte 2Byte 1
Edition 2.0 MB86687A
25
3.5.8 TXDRV (TX cell stream Drive):
Earlier ALC devices needed pull down
resistors on the TX cell stream interface
because the selection of Cell Stream
Daisy Chaining was controlled by a
register. Using the TXDRV signal on
MB86687 allows these resistors to be
omitted.
This mode is selected by tying the
TXDRV pin low. By default, it is
deselected by an internal pull–up resistor
and the register controls the operation.
3.5.9 Receive Circuit Reference
and VPI/VCI Filter Mechanism
The ALC constructs a 10 bit receive
circuit value depending on the setting of
the RID bit in register 17.
RID 0
Receive Circuit Reference value is equal
to VPB least significant bits of the VPI
field concatenated with (10–VPB) least
significant bits of the VCI field where VPB
is the value of VPI bits to be used in the
receive address mapping, specified by
bits VPB2, VPB1 and VPB0 in register 16.
AF17–AF14 matched with VPI11–VPI8
for NNI mode.
AF17–AF14 are not considered for UNI
mode.
AF13–AF0 matched with unused VPI bits
concatenated with unused VCI bits.
For VPI filter inactive (VPF=0) the mask
bits for the unused VPI bits must be
cleared to zero.
RID 1
Receive Circuit Reference is equal to the
value in the MID field (AAL3/4 only).
The Receive Circuit Reference value
should be used during programming
register 59 when enabling receive
channels. When re–assembling a
packet, this value is loaded into the
receive circuit reference field in the
receive descriptor.
The ALC performs filtering on the VPI and
VCI bits not used for the receive circuit
value. Bits AF17 and AF16 in register 16
together with bits AF15 – AF0 in register
56 make up the mask value to be used to
filter incoming cells. Programming of the
mask bits AF17–AF0 is dependent on the
settings of the UNSEL bit in register 16
and the VPF bit in register 17.
Edition 2.0MB86687A
26
3.6 Microprocessor Interface
The Microprocessor Interface is
responsible for supporting the following
functions:
Providing Host Processor access to
all programmable ALC registers,
Providing the Host Processor
initialisation / test access to the
Receive Status / Descriptor Tables,
Managing the ALCs interrupt
mechanism.
3.6.1 Interrupt Controller
The ALC will indicate certain abnormal
conditions using the Interrupt signal. The
cause of an interrupt is provided in the
Interrupt status register.
Each interrupt condition can be
individually masked to prevent external
interrupt signal generation. A full
description of each interrupt source is
given in Appendix B., Fig. 45 and Fig. 46
as part of the interrupt status register
description.
Edition 2.0 MB86687A
27
3.7 Segmentation and Reassembly Memory Interface
3.7.1 Features
The SAR interface is responsible for
accessing queues, tables and data
stored in either dedicated dual port
memory or within the host system
memory. The SAR interface can support
the following features:
Motorola or Intel compatible bus
cycles
Examples of Motorola and Intel Mode
Normal Read cycles are shown in Fig. 13
and Fig. 14 respectively.
Extended Intel (486) & Motorola (040)
modes.
These modes allow Single Cycle data
bursts. Examples of the Intel extended
normal and burst read cycles are shown
in Fig. 15 and Fig. 16 respectively.
Addressing Schemes
Little or Big Endian addressing
schemes in Intel mode;
Big Endian addressing schemes in
Motorola mode.
Other Features
Direct connection to Dual Port RAM;
Bus arbitration as required in DMA
mode;
DMA burst length limiting in the range
1 to 255 memory cycles.
READY/DTACK extended cycles in
Ready dependent SAR memory
mode.
Memory contention interrupt
generation in response to
READY/DTACK transition when using
Fast Cycle Mode.
SADRV ( TX cell stream Drive) –
Using the SADRV signal on MB86687
allows pull–up resistors to be omitted.
Earlier ALC devices needed pull–up
resistors on all the address and
control signals because the selection
of DPR or DMA modes was controlled
by a register.
This mode is selected by tying the
SADRV pin low. By default, it is
deselected by an internal pull–up resistor
and the register controls the operation.
Edition 2.0MB86687A
28
**CS
A0 – 23
R/W
DATA
Fig. 13 – Motorola 32 Bit Mode – Normal Mode Read Timing
SIZ0–1
AS
DTACK
DCCK
DS
**CS
A0 – 23
BLAST
RD
DATA
Fig. 14 – Intel 32 Bit Mode – Normal Mode Extended Read Timing
BE0–3
READY
DCCK
READY is sampled on the falling edge of
DCCK at the end of state 3. The example
shown uses a synchronous READY
signal.
An asynchronous READY signal takes
one extra clock cycle to take effect due to
internal synchronisation.
Edition 2.0 MB86687A
29
**CS
A0 – 23
BLAST
R/W
DATA
Fig. 15 – Intel 486 Mode – Normal Reads Timing
BE0–3
ADS
READY
DCCK
**CSn
**CSn+1
ADDR
BLAST
R/W
DATA
Fig. 16 – Intel 486 Mode Single Cycle Burst Timing
BE0–3
ADS
READY
DCCK
Edition 2.0MB86687A
30
3.7.2 Start of Cycle Signals
There are four start of cycle signals. They
are as follows :–
TOCS
Transmit Overhead Cycle Start output.
TDCS
Transmit Data Cycle Start output.
ROCS
Receive Overhead Cycle Start output.
RDCS
Receive Data Cycle Start output.
These start of cycle signals are asserted
before the associated operation. In
normal mode, this will be one clock cycle
before the next operation. In Ready
Dependent mode where cycles are back
to back, the signal will be asserted during
the second clock of the previous cycle. In
shared memory systems, this period may
be indeterminate because an active start
of cycle may be asserted for an operation
that will occur after the bus has first been
released and then regained. When
stealing or forced bursting is enabled a
single start of cycle pulse may precede a
group of consecutive operations of the
same type.
DCCK
TDCS
TOCS
RDCS
ROCS
ADDRA
MRD
MWR
DATA
Memory Data ALC Data
Fig. 17 – Start of Cycle Signal Timing – Fast Mode Extended Read
Parity Bits
Parity generation and detection on a per byte basis is supported on the SAR memory
interface using four bi–directional signals.
Edition 2.0 MB86687A
31
A register bit determines if the parity
generation/ checking is to be odd or
even. If a parity error occurs an interrupt
is generated. This interrupt cannot be
disabled. The ALC does not drop bytes, it
purely informs the host that an error has
occurred.
3.7.3 DMA Cycle Optimisation
The ALC can be programmed to change
the cycle ordering on its DMA interface to
be optimal for different system
configurations This is achieved by
progressively setting more bits in the
most significant word of the DMA Mode
Register. The settings are as follows:–
0H – cycles are compatible with 86A
ready dependent cycles.
1H – cycles are compatible with 86A
fast cycles with stealing on data
cycles only.
7H – cycles are optimised for dual port
RAM systems with stealing of data
and overhead cycles.
1FH – cycles are optimised for shared
memory systems where there may be
different memory partitions. The
cycles will be grouped according to
their type.
3.7.4 Transmit DMA CACHE
The ALC uses shared or private memory
to create and maintain queues of data
packets, packet segmentation
information and traffic management
data.
To reduce the number of overhead cycles
used to access these, a caching
mechanism may be used whereby the
parameters for up to 128 circuits can be
stored on–chip.
The cache is operated in the following
way and requires a small processor
overhead to maintain a table of cached
entries.
The host software assesses the traffic
requirements of each circuit and
makes a decision about which circuits
would benefit being in the cache.
The host signals to the ALC that a
circuit should be cached via the
Circuit Reference Table using the
cache start bit and address fields.
The host then schedules a packet or
packets via the TPQ mechanism.
On its first pass through the data
structures, the ALC fetches the
appropriate parameters from the
Circuit Reference Table and the
current Transmit Descriptor and
stores them on chip.
Subsequently the ALC will process
the internal copies of its data
structures.
Further queued packets will cause the
ALC to fetch the new Transmit
Descriptor information only.
Edition 2.0MB86687A
32
On completion of the packet, if no
more packets are queued, the cache
entry will remain valid but idle until a
new packet is queued or the entry is
overwritten with a new entry.
Additional codes added to the Buffer
Release Queue return codes will
notify the host when all packets for a
particular circuit have been
assembled. At this time the host can
choose to re-use the cache entry for
another circuit.
Edition 2.0 MB86687A
33
4. DEVELOPERS NOTES
4.1 Configuration Control Issues
This section is intended to give an
overview of the ALC from a system
programmers perspective. The following
operations need to be performed by the
host to configure the ALC.
Set up the shared data structures,
Set up queue addresses,
Set up queue service rate
parameters,
Program ALC mode registers.
During normal operation the host is also
required to perform the following
operations.
Pass user data buffers to the ALC for
transmission,
Reclaim used transmit buffers from
the ALC for reuse after transmission
completes,
Allocate receive buffer space for use
by the ALC,
Receive packets when completion is
indicated by the ALC,
Activate and de-activate virtual
circuits,
Respond to exception interrupts as
required.
These operations are explained in more
detail below.
4.2 Transmit Data Structures
A diagramatic view of the transmit side
data structures is shown in Fig. 18, a
detailed view of the pointer mechanism in
Fig. 19 and a diagramatic view of the
queue structure in Fig. 22. Before data
can be transmitted the host has to
programme the ALC with the base
address of the following transmit data
structures: Transmit Descriptor Table,
Circuit Reference Table, Transmit
Pending Queue and the Transmit Buffer
Release Queue.
In addition the host has to initialise the
appropriate entries in the Transmit
Descriptor and Circuit Reference Tables.
4.2.1 Transmit Descriptor Table
The Transmit Descriptor Table is
composed of a contiguous list of Transmit
Descriptors (TDs). The host composes a
TD for each packet to be transmitted and
adds the TD to the TD table. The table
can contain up to 4096 TDs. A TD is
composed of the fields shown in Fig. 20
on page 36.
Diagrams showing the implementation of
transmit queue organisation and
calculation of pointer addresses for both
TDs and Circuit Reference table entries
are given on the following pages.
Edition 2.0MB86687A
34
TRANSMIT
PENDING
QUEUE
TRANSMIT
BUFFER
RELEASE
QUEUE
Entry 0
1
2
3
4
5
6
7
.
.
etc.
ALC
CIRCUIT REFERENCE TABLES
TRANSMIT DESCRIPTORS
PACKET
BUFFER
(PAYLOAD)
host write
host read
See Fig. 21 for CRT entry format
See Fig. 20 for TD format
Fig. 18 – Transmit Data Structures
Transmit Descriptors contain
packet information including:
– length
– start of data pointer
Circuit Reference Tables
include traffic parameters
and cell header information
Entry 0
1
2
3
4
5
6
7
.
.
etc.
SAR MEMORY
Edition 2.0 MB86687A
35
Fig. 19 – Transmit Data Structures – Address Calculation
00000
TRANSMIT PENDING QUEUE TRANSMIT BUFFER RELEASE QUEUE
ALC READ PTR
HOST WRITE PTR
TRANSMIT DESCRIPTOR BASE ADDRESS
TRANSMIT DESCRIPTOR REFERENCE
DESCRIPTOR REFERENCE0000
ALC WRITE PTR HOST READ PTR
CIRCUIT REFERENCE BASE ADDRESS
00000000 TRANSMIT DESCRIPTOR BASE ADDRESS 00000000
00000000
00000TRANSMIT DESCRIPTOR REFERENCE +
TRANSMIT DESCRIPTOR TABLE
+
ENTRY m
ENTRY n
+
CIRCUIT REFERENCE 0000
CIRCUIT REFERENCE TABLE
PACKET m PACKET n
CIRCUIT REFERENCE BASE ADDRESS 00000000
+
CIRCUIT REFERENCE 0000
CIRCUIT yCIRCUIT x
ENTRY x
ENTRY y
ADDRESS
POINTER
ADDRESS
POINTER
ADDRESS
POINTER
ADDRESS
POINTER
DESCRIPTOR REFERENCE0000
CCT REF
CCT REF
Edition 2.0MB86687A
36
CIRCUIT REFERENCEMID
031
M
Fig. 20 – Transmit Descriptor
CS CG
15
PT
UNUSED
AVAILABLE FOR USER SOFTWARE
RESERVED
RESERVED
TRANSMIT BUFFER SIZE
BUFFER START ADDRESS
AAL5 CONTROL FIELD /
NEXT CHAINED DESCRIPTOR REFERENCE
REMAINING BYTES FOR SEGMENTATION
CE
S
91326 25 10
RESERVED
2324
CBS LBRABT IOC CLP RES
BA SIZE/LENGTH FIELD
0
M (More)
The host sets this bit to 0 to indicate that
the transmit buffer associated with this
TD contains the End of Message
segment of the CS–PDU. The ALC will
append a CS–PDU trailer after the end of
this buffer. All other TDs associated with
the buffer should have M set to 1.
S (Segmenting)
This bit is set by the ALC to indicate that
segmentation is in progress on the
transmit buffer. The host sets the S bit to
zero before passing the TD to the
Transmit Descriptor Table.
CE (Chain End)
The host sets this bit to 0 to indicate that
this is the last TD in the chain. If CE is set,
the ALC assumes that the Next Chained
Descriptor Reference field is valid.
CS (Chain Start)
The host sets this bit to indicate that the
associated transmit buffer is not the first
buffer of a chain or stream of descriptors.
This bit is used for AAL3/4 or for AAL5
when using external calculation of
Convergence Sublayer parameters.
CG (Congestion indication)
The host sets this bit to indicate that ATM
cells generated from the associated
buffer should have the congestion
notification bit set in the Payload Type
Field.
Edition 2.0 MB86687A
37
PT (Pass Transparent)
The host sets this bit to indicate that the
ALC should set the CG bit in the PTI field
and CLP bit of the ATM cell header
directly as coded in the Circuit Reference
Table for each cell, otherwise the CG and
CLP bits are as programmed in the
Transmit Descriptor.
MID (Multiplexing Identification)
The ALC writes this ten bit field into the
ATM cell’s MID field.
ABT (Abort)
The host sets this bit to instruct the ALC to
transmit an Abort cell as defined for
streaming mode operation. When an
abort AAL3/4 or AAL5 cell has been
transmitted the following queued
descriptor should not have the CS bit set
ie. it should be the first descriptor in a new
packet.
IOC (Interrupt On Completion)
The host sets this bit to indicate that the
ALC should generate an interrupt when
segmentation of the Transmit Descriptor
buffer is complete.
CLP (Cell Loss Priority bit)
The host sets this bit to indicate that ATM
cells generated from the associated
buffer should have the CLP bit set = 1.
CBS (Copy Buffer Size)
The host should set this bit if the Transmit
Buffer Size field is the initial value for
bytes for segmentation.
LBR (Leaky Bucket Reset)
The host should set this bit if the leaky
bucket variable capacity is to be
re–initialised the first time data is
re–assembled from this TD.
Circuit Reference
This field is a 10 bit index into the Circuit
Reference Table. It is shifted left by 4 bits
then added to the Circuit Reference
Table base address (shifted left by 8 bits )
to generate a pointer to the appropriate
entry in the Circuit Reference Table. The
circuit reference index could be either the
VCI or MID of the connection.
Remaining Bytes for Segmentation
This field is initially loaded with the total
number of bytes in the packet for
segmentation. This field is modified by
the ALC during packet transmission. In
streaming and chaining modes, the
length of each buffer can be any number
of bytes provided that the next streamed
or chained buffer can fill any remaining
partially assembled cell. In streaming
mode a buffer that does not terminate on
a cell boundary will be held by the ALC
until a subsequent buffer is linked on.
BA Size / Length Field
In AAL 3 /4 mode the ALC transmits this
value in the BA Size field of the AAL 3/4
CS–PDU header . In AAL5 mode the AAL
transmits this value in the AAL5 CS–PDU
trailer LENGTH field.
Reserved 0
These fields are for internal ALC usage.
They should be initialised to 0 and reset
to 0 when the host retrieves the transmit
descriptor through the transmit buffer
release queue but otherwise should not
be used by the host.
Reserved
These fields are for internal ALC usage
and should not be used by the host.
Edition 2.0MB86687A
38
Buffer Start Address
This 24 bit pointer provides the ALC with
the start address of the associated
transmit buffer. Any number of header
bytes can be read from a user data buffer
by writing the correct byte (non 32 bit
aligned) address to this location.
AAL5 Control Field /
Next Descriptor Reference
In chaining mode the host programs the
next descriptor reference in the chain into
this field. In AAL5 mode, this field
contains the Control Field of the CS–PDU
trailer only if this is the final TD in the
chain.
Transmit Buffer Size
This 16 bit value is set by the host. It
specifies the number of bytes in the
associated transmit buffer. This field is
optionally used by the ALC, if the CBS bit
is set, as the initial value of bytes for
segmentation.
Available for User Software
This field is not used by the ALC and will
not be used by future ALC devices. This
field may be utilised by user software.
Re–initialisation of Transmit Descriptors
Field Mode
Message Chaining Streaming
Segmenting (S) bit 0 0 0
AAL5 Control/
Next Chain set AAL5: control in last TD
Next chain descriptor Set last TD only
Buffer
Start Address Programmed by Host
AAL3/4 BASIZE
AAL5 Length set * AAL3/4: BASIZE in first TD
AAL5: length in last TD *
Bytes remaining Programmed by Host **
Reserved 0 Program to 0
Note * In AAL5, if the MAAL5 bit is set, this value is computed automatically by the ALC.
Note ** If copy buffer size is set, this field will be refreshed by the ALC to the value in the Transmit Buffer Size field.
4.2.2 Circuit Reference Table
The Circuit Reference T able is composed
of a list of contiguous Circuit Reference
entries. There is a Circuit Reference for
each active Virtual Circuit. Each Circuit
Reference Table entry contains the ATM
Cell header and the Leaky Bucket
parameters for the relevant VC. The
Circuit Reference is composed of the
following fields, see Fig. 21.
Routing Tag 0 – 3
Optional routing tag appended in
applications where the ALC is interfacing
directly with a Fujitsu Self Routing Switch
Element MB86680 device or any similar
device. Up to three octets of routing is
supported.
GFC – Generic Flow Control,
VPI – Virtual Path Identifier,
Edition 2.0 MB86687A
39
VCI – Virtual Channel Identifier,
PTI – Payload Type Identifier,
CLP – Cell Loss Priority.
These form the ATM Header Field as
defined by the UNI Specification. The
ALC will code the PT bit of the PTI field
according to the state of assembly of the
SDU.
U, Leaky Bucket utilisation parameter
This field contains the average rate of cell
transmission for leaky bucket
management expressed as a ratio of the
peak rate. The coding is as follows:
891011
1 1/2 1/4 1/8
Bit no.
Peak Rate
Ratio
The host can select any combination of
bits to generate the required average
rate. If the ratio is programmed to 1, the
peak and average rates will be identical
which could be used for constant bit rate
traffic. Average rates greater than 1 are
not supported.
ECS (External Calculation of SPCS)
This single bit instruction is used to select
the use of external memory for AAL5
CRC32 and AAL3/4 length field and
sequence number storage. This set by
the host for non–cached entries when
internal memory is not available. (Each
cache entry uses the storage of 8
equivalent VC entries)
Additionally used in transparent cell and
transparent payload to indicate to the
ALC that the CRC10 should be
calculated and placed in the last 10 bits of
the payload.
LEAKY BUCKET CAPACITY
031
VPIGFC
ROUTING TAG0 ROUTING TAG1 ROUTING TAG2
VCI
Fig. 21 – Circuit Reference Table Entry
SRS SQN AALT
RESERVED VARIABLE (M*)
347811121516192023242728
LEAKY BUCKET CAPACITY
CONSTANT (M)
C
L
P
1256
00000000
RESERVED UTILISATION
(U)
RESERVED
E
C
S
C
H
S
C
H
S
T
S
C
E
VCADDRESSRESERVED
P
T
I
Edition 2.0MB86687A
40
CHS (Cache Start)
Set by HOST.
CHSTS (Cache Status)
Initialised to ’0’ by the HOST, set by ALC.
CEV (Chain End Valid)
Initialised to ’0’ by the HOST, set by ALC,
CADDRESS (Cache Address)
(7 bit field): set by HOST; valid if the CHS
bit is set.
SRS (Sub-Rate Select)
These bits are used to select the required
sub-rate of the nominal transmit queue
peak rate. The coding is as follows.
67
01
Bit no. Sub-rate
selected
10
11
25%
50%
100%
0 0 see below
If the Circuit Reference Table for a circuit
is programmed with SRS=00 and
AALT=11 (AAL5 only) then the ALC will
omit leaky bucket calculations on
transmit for that circuit. This reduces
transmit overhead accesses for circuits
with 100% utilisation. This facility is
available on the high and medium priority
queues only.
SQN (Service Queue Number)
The host uses this field to assign the
associated Virtual Circuit to one of the 12
peak rate queues. The coding is as
follows:
34
00
Bit no. Peak Rate Queue
1010
Queue 1
Queue 12
52
01
Queue 1 corresponds to Low Priority and
Queue 12 corresponds to High Priority.
AALT (ATM Adaption Layer Type)
This field is used to specify the AAL type
for the VC. Two transparent modes can
also be selected. The coding is as
follows:
01
01
AAL Type selected
10
11
AAL 3/4
Transparent Payload
Transparent Cell
00
AAL 5
Edition 2.0 MB86687A
41
M (Leaky Bucket capacity constant)
M in the Circuit Reference Table entry is
the bucket capacity used to implement
leaky bucket averaging on a per VC
basis. The host programmes this field
with a Leaky Bucket capacity in the range
of 1 – 255. The relationship between the
bucket capacity (M), the utilization (U)
and the maximum burst length (B) at the
selected peak rate is given by:
M = ( B – 1 ) x ( 1 – U )
for single leaky bucket method and by:
M = B x ( 1 – U )
for double leaky bucket method.
Note:
If the resulting M value is not an integer
then in the single leaky bucket case M
should be rounded DOWN to the nearest
integer and in the double leaky bucket
case M should be rounded UP to the next
integer.
Also, for the single leaky bucket case a
minimum value of B is specified for each
utilization value as given below:
U = 0.875 minimum allowed B = 9,
U = 0.75 minimum allowed B = 5,
U = 0.625 minimum allowed B = 4,
For all other values of U the minimum
value allowed for B is 3.
M* (Leaky Bucket capacity variable)
The ALC uses this variable to implement
leaky bucket averaging on a per virtual
circuit basis. The host initially sets M* to
the same value as M, M* is then modified
by the ALC as the ALC implements the
leaky bucket algorithm for that VC. The
ALC uses the constant value M for
reference when carrying out leaky bucket
calculations. M* may also be refreshed to
M when the LBR bit is set in a TD.
Reserved
These fields are for internal ALC usage
and should not be used by the host.
4.2.3 Transmit Pending Queue
The transmit pending queue is used by
the host to instruct the ALC to queue a
transmit packet for segmentation. Each
command passed to the queue includes
a 12 bit index reference into the T ransmit
Descriptor table. A Transmit Pending
Queue entry is shown in Fig. 23.
This queue is defined by registers 2 – 6.
The Host Processor must assign values
for the Transmit Pending Queue base,
start address, end, read and write
pointers. The initial values of the read
and write pointers should be the start
address to reflect an empty queue.
To pass a new entry to the TPQ the Host
Processor should read the current value
of the on-chip write register . This address
should be used to store the new TPQ
entry. The host should then update the
write pointer register , wrapping around to
the start address if necessary.
Edition 2.0MB86687A
42
When the DMA Controller has available
transmit bandwidth (or once every five
segmentation periods), i.e a cycle where
cell segmentation is not required, it reads
the value of the Transmit Descriptor
Reference addressed by its internal read
pointer.
In addition, the T ransmit Pending Queue
can be used as follows:
DUtilisation adjustment;
The U value in the CRT pointed to by the
associated TD will be set to the given
value.
For cached entries, a dummy circuit
reference entry should be used to point to
the required cached address and the
CHS bit set.
DSend Express Cell;
If an entry is placed on the queue with the
1 100 coding then it will not be assigned to
a rate queue but will be sent immediately .
For streaming mode when transmitting
packets using non–integral cell length
buffers, the host may queue a last stream
transmit descriptor which results in the
cell started in the current buffer being the
last cell of the packet. For this case, the
last stream transmit descriptor must be
queued as follows:
DTPQ code=1010 if remaining bytes for
segmentation is zero;
DTPQ code=1001 if remaining bytes for
segmentation is non–zero.
Transmit
Buffer
Ready
Queue
Transmit
Pending
Queue
Receive
Buffer
Ready
Queue
Receive
Buffer
Free
Queue
Read
Write
H
O
S
T
REG 5
: REG 3
: = Start and End addresses
: REG 4
REG
6REG
44
REG
9REG
48
REG 10
: REG 7
: REG 8
Read
Read Write
REG 43
Read
REG 49
WriteWrite
: REG 46
: REG 47
: REG 41
: REG 42
Fig. 22 – ALC Queue Structures
ALC
TRW Interrupt RRW Interrupt
H
O
S
T
Edition 2.0 MB86687A
43
0 0 0 0 Queue Packet
Fig. 23 – Transmit Pending Queue Format
TPQ Code
01115 TRANSMIT DESCRIPTOR REFERENCE
0 0 0 1 Set Utilisation to 0.125
0 0 1 0 Set Utilisation to 0.25
0 0 1 1 Set Utilisation to 0.375
0 1 0 0 Set Utilisation to 0.5
0 1 1 0 Set Utilisation to 0.75
0 1 1 1 Set Utilisation to 0.875
1 0 0 0 Set Utilisation to 1.0
0 1 0 1 Set Utilisation to 0.625
1 0 0 1 Queue last cell (streaming – bytes remaining)
1 0 1 0 Queue last cell (streaming – no bytes remaining)
1 1 0 0 Queue Express Cell
1 1 1 1 Set Utilisation to 0
4.2.4 Transmit Buffer Release
Queue
The ALC returns segmented transmit
buffers to the host using the Buffer
Release Queue. Each queue entry will
contain a 12 bit reference index into the
T ransmit Descriptor table. A queue entry
is shown in Fig. 24.
This queue is defined by registers 2 and
7 – 10. The Host Processor must assign
values for the Buffer Release Queue
base, start address, end, read and write
pointers.
The initial values of the read and write
pointers may be the start address to
reflect an empty queue or the write
pointer may be set to the read pointer
minus 1 to reflect a pool of free buffers.
To release a buffer to the host the ALC
increments the TBRQ write pointer and, if
the IOC bit in the Transmit descriptor is
set, generates an interrupt. The host may
then choose to immediately
acknowledge this action by updating the
TBRQ read pointer or if using the queue
as a pool of free buffers, only update the
pointer when reusing the TD.
Edition 2.0MB86687A
44
Fig. 24 – Transmit Buffer Release Queue Format
01115
0 0 0 0 Default code
0 0 0 1 Changed Utilisation
TRANSMIT DESCRIPTOR REFERENCE
0 0 1 0 Packet complete. No further packets for this circuit
0 0 1 1 Packet complete. No further packets for this queue
12
BRQ Code
0 1 0 0 Buffer complete. Moving to next streamed buffer
0 1 1 0 Buffer complete. Awaiting next streamed buffer
0 1 0 1 Changed utilisation to 0
0 1 1 1 Buffer complete. No further packets in this queue. Awaiting next streamed buffer
1 0 0 0 Buffer complete. Not end of chain
1 0 1 0 Express Cell Sent
1 1 0 0 Abort sent
1 1 1 1 Abort sent. No further packets in this queue
1 1 1 0 Abort sent. No further packets for this circuit
4.2.5 INCWRAP – Wrap and
Increment Mechanism
When writing to the host–controlled
queue registers, if the most significant bit
of the control data bus is set, the ALC will
automatically increment its internal copy
of the pointer being written to regardless
of the pointer value specified on the data
bus.
T wo status conditions are available when
reading the host–controlled pointers:
EMPTY condition
If this bit is set, it indicates that the ALC’s
pointer for the queue is at the same value
as the host pointer’s value returned by
the read and that the queue is empty.
FULL condition
If this bit is set, it indicates that the host
pointer and ALC pointer values are the
same and that the queue is full.
Edition 2.0 MB86687A
45
4.3 Receive Data Structures
A detailed view of the receive data
structures is shown in Fig. 25, a detailed
view of the pointer mechanism in Fig. 26
and a diagramatic view of the queue
structures in Fig. 22. Before data can be
received the host has to programme the
ALC with the base address of following
receive data structures: Receive
Descriptor Table, Receive Buffer Free
Queue and the Receive Buffer Ready
Queue.
4.3.1 Receive Descriptor Table
The Receive Descriptor Table is
composed of a contiguous list of Receive
Descriptors (RDs). The host is
responsible for composing sufficient RDs
to handle the expected number of receive
packets.
Each time a start of packet cell is received
the ALC will use the next entry in the
Receive Buffer Free Queue to locate the
relevant RD in the table. A typical RD is
composed of the fields shown in Fig. 27
on page 48.
Diagrams showing the implementation of
the Receive queue organisation and
calculation of pointer addresses for RDs
and field entries are given on the
following pages.
V (Valid)
The ALC sets this bit to 1 to indicate that
the Next Chain Descriptor field in this
descriptor is valid. This is used in
chaining mode when the received packet
does not terminate in the current receive
buffer. When this bit is cleared to 0 it
indicates that the chain of receive buffer
descriptors terminates with this
descriptor. The host is required to
initialise this bit to 0 and also in chaining
mode to clear this bit to 0 before returning
the receive descriptor to the ALC through
the buffer free queue.
Next Chain Descriptor Reference
When receive buffer chaining is used this
12 bit field is programmed by the ALC
with the descriptor reference of the next
receive descriptor in the chain.
Reserved
These fields are for internal ALC usage
and should not be accessed by the host.
Receive Circuit Reference
This 10 bit field is programmed by the
ALC with the receive channel supplying
data to the associated receive buffer.
This channel number will imply a
particular VP/VC according to the
programming of VPB2, VPB1 & VPB0 in
Register 16. If chaining is used, this value
is only valid in the first descriptor of the
chain.
CLP (Cell Loss Priority)
The ALC sets this bit to indicate that the
last ATM cell re–assembled into the
associated buffer had the CLP bit set = 1.
CI (Congestion Indication)
The ALC sets this bit to indicate that the
last ATM cell re–assembled into the
associated buffer had the CI bit set = 1.
GFC (Generic Flow Control)
The ALC sets this field to the GFC value
in the last ATM cell reassembled into the
associated buffer.
Edition 2.0MB86687A
46
BUFFER
FREE
QUEUE
BUFFER
READY
QUEUE
Entry 0
1
2
3
4
5
6
7
.
.
etc.
ALC
RECEIVE DESCRIPTORS
PACKET
BUFFER
(PAYLOAD)
host write
host read
See Fig. 27 for descriptor format
Fig. 25 – Receive Data Structures
Receive descriptors contain
reassembled packet
information including:
– length
– start of data pointer
Entry 0
1
2
3
4
5
6
7
.
.
etc. SAR MEMORY
RECEIVE
DESCRIPTOR
TABLE
1000
Edition 2.0 MB86687A
47
RECEIVE BUFFER FREE QUEUE RECEIVE BUFFER READY QUEUE
ALC READHOST WRITE HOST READALC WRITE
Fig. 26 – Receive Data Structures – Address Calculation
DESCRIPTOR REFERENCE
RECEIVE DESCRIPTOR BASE ADDR
+00000
DESCRIPTOR REFERENCE0000
00000000
0
1515 0
DESCRIPTOR REFERENCE
RECEIVE DESCRIPTOR BASE ADDR
+00000
00000000
PACKET m PACKET n
RECEIVE DESCRIPTOR TABLE
ENTRY m
ENTRY n
ADDRESS
POINTER
ADDRESS
POINTER
DESCRIPTOR REFERENCE0000
Unused
These fields should not be utilized by
user software but may be cleared to 0 by
the host.
Buffer Size
If the RDAU bit is set in Register 16, this
value is automatically copied into the
Remaining Capacity field when the RD is
first accessed. The value is not modified
by the ALC.
Available for User Software
This field is not used by the ALC and will
not be used by future ALC devices. This
field may be utilized by user software.
Edition 2.0MB86687A
48
NEXT CHAIN
RECEIVE CIRCUIT
031
Fig. 27 – Receive Descriptor
RESERVED
15
BUFFER START ADDRESS
TOTAL LENGTH
V
UNUSED
RESERVED
REMAINING CAPACITY
UNUSED
AVAILABLE FOR USER SOFTWARE
BYTES RECEIVED
AAL5 CONTROL FIELD /
11
DESCRIPT OR REFERENCE
14
REFERENCE
12 91013
RESERVED
23242728
AAL3 RESERVED
RESERVED
C
L
PC
I
BUFFER SIZE
GFC
Bytes Received
This 16 bit field is programmed by the
ALC with the number of bytes written to
the associated receive buffer.This field
should be initialized to 0 and reset to 0
before returning the descriptor for reuse
through the buffer free queue. This count
is always a multiple of 4 bytes and hence,
will include up to 3 bytes of pad at the end
of a packet.
Remaining Capacity
This field indicates the number of unused
bytes within the associated buffer. This
field should be initialized to the buffer
capacity and reset to the buffer capacity
before returning the descriptor for reuse
through the buffer free queue. This count
is always a multiple of 4 bytes and hence,
will include up to 3 bytes of pad at the end
of a packet.
Buffer Start Address
This 24 bit pointer is programmed by the
host with the start address of the receive
buffer associated with this descriptor.
AAL5 Control Field /
AAL3 Reserved
When AAL5 is selected this field is used
to hold the received AAL5 control value
obtained from the incoming CS–PDU
trailer. If chaining is enabled then this field
is only valid in the initial receive
descriptor of the chain. In all other
descriptors in the AAL5 chain this field is
reserved. In AAL 3 for all descriptors this
field is reserved. In chaining mode this
field should be initialized to 0 and reset to
0 before returning the descriptor for
re–use through the buffer free queue.
Total Length
This 16 bit value is programmed by the
ALC with the total length field received in
the CS–PDU trailer. If chaining is used
then this field contains the total length
only in the initial receive descriptor of the
chain. In chaining mode this field should
be initialized to 0 and reset to 0 before
returning the descriptor for reuse through
the buffer free queue.
Edition 2.0 MB86687A
49
Re–initialisation of Receive Descriptors
Field Mode
Message Chaining Streaming
V & next chain RD N/R 0 N/R
Bytes Received 0 *0 *0 *
Remaining Capacity buffer size ** buffer size ** buffer size **
BufferStart Address Programmed by Host
AAL5 Control/AAL3 Reserved 0 0 0
Total Length N/R 0 N/R
N/R Reinitialisation not required
Note * If RDAU is set in Register 16, Bytes Received is automatically cleared when the RD is first accessed;
Reinitialisation is then not required.
Note ** If RDAU is set in Register 16, Buffer Size is automatically copied into Remaining Capacity when the RD
is first accessed. Reinitialisation is then not required.
4.3.2 Receive Buffer Free Queue
The Receive Buffer Free Queue is used
by the ALC to locate the next Receive
Descriptor each time a new packet is
received.
Each queue entry contains a reference
into the Receive Descriptor table. The
format of a queue entry is shown in
Fig. 28.
4.3.3 Receive Buffer Ready Queue
The ALC passes reassembled packets to
the host using the Receive Buffer Ready
Queue. Each queue entry contains a
reference to the relevant Receive
Descriptor . In addition the ALC writes the
status of the received packet to the Buffer
Ready Queue. The format of each queue
entry is shown in Fig. 29.
4.3.4 Increment and Wrap
Mechanism
This mechanism is similar to that used by
the transmit queues and is described in
section 4.2.5.
Fig. 28 – Buffer Free Queue Format
UNUSED
01115
RECEIVE DESCRIPTOR REFERENCE
12
Edition 2.0MB86687A
50
Fig. 29 – Receive Buffer Ready Queue Format
RBRQ Status
01115
0 0 0 0 Reassembly Complete With No Errors ( M=0 )
0 0 0 1 Buffer Complete With No Errors (M = 1)
RECEIVE DESCRIPTOR REFERENCE
0 0 1 0 Reassembly Complete With f5 OAM cell – CRC10 passed
0 0 1 1 Reassembly Complete With f4 or f5 OAM cell – CRC10 failed
0 1 0 0 Reassembly Complete With f4 OAM cell – CRC10 passed
0 1 0 1 Sequence Number Error
0 1 1 0 Invalid Length Indication
0 1 1 1 Partial reassembly: Missing EOM
1 0 0 0 Receive Buffer Overflow
1 0 0 1 Receive Maximum Length Exceeded
1 0 1 0 No Chaining buffers Available
1 0 1 1 AAL3 Trailer Error Indication
1 1 0 0 Buffer Timed Out Reassembly Aborted
1 1 0 1 Packet Length Error Indication
1 1 1 0 RAS Abort Indication (Reassembly Streaming)
1 1 1 1 AAL5 CRC 32 Error Indication || AAL3 BTag / ETag mismatch
12
Edition 2.0 MB86687A
51
4.3.5 Receive Descriptor Table
Access Mechanism
Writing to the Table
The write to RSD table process operates
in the following way. The host sets the
data intended for the RSD by writing it to
the Host Receive Descriptor/Status
T able Write Register (Register 58) – (This
will normally involve setting the ACT bit
when a channel is about to be activated).
The host then writes to the Host Receive
Descriptor/Status Table Access Register
(Register 59). The HOSTR and RD/WR
must be set to generate the internal write
to the RSD table. The values in Register
58 together with the AAL bits from
Register 59 are written into the RSD table
at the address specified by the VCI
values in Register 59.
The TAC interrupt will be generated in
response to the write to Register 59 to
inform the host that the RSD table has
been updated.
Reading from the Table
The read from RSD table process
comprises the following sequence of
events. The host writes to Register 59
setting HOSTR and clearing RD/WR.
This causes the ALC to carry out an
internal read to the RSD table using the
address specified by the VCI value in
Register 59.
The contents of the read are written to the
Host Receive Descriptor/Status Table
Read Register (Register 57) and the T AC
interrupt is generated indicating to the
host that Register 57 has been updated.
The host then reads the RSD table
contents from Register 57.
Notes
Register 57 is read only.
Accesses to Registers 57 and 58 have no
effect on the RSD table until Register 59
is written to.
During normal operation, Register 59
should not be written to with HOSTR and
RD/WR (bits D15 and D14) set after the
initialisation stage.
4.3.6 OAM Cell Handling
The ALC will flexibly handle incoming
OAM cells.
The ALC considers a cell to be an F5
OAM cell if the most significant bit of the
PTI field is set. This means that resource
management cells (PTI field = 110) are
also treated as these cells.
The ALC considers a cell to be an F4
OAM cell if the cell arrives on a channel
which has the RIP bit set and the AAL bits
set for T ransparent Cell mode (10) in the
RSD table.
If the DCOAM bit (CR16) is set, only F5
OAM cells are discarded. Discarded
OAM cells do not alter the dropped cell
counter value.
If cleared, the OAMCRC bit (CR16) only
disables CRC10 checking on F5 OAM
cells. The ALC always performs CRC10
checking on F4 OAM cells.
Edition 2.0MB86687A APPENDICES
52
A. REGISTER TABLE
The ALC register address table is shown
on the following pages. Please note that
the Register Tables TYPE field indicates
the type of host access cycle used to
access each register.
Abbreviations used are as follows:
R/O = Host read access only.
W/R = Host read/write access
W/O = Host write access only.
(T) = After initialisation, these
registers are updated using TCLK
and have a recovery time dependent
on TCLK.
CW/R = Host write access only after
setting the control write enable bit
(CWRE) of the ALC Control Register.
The Registers listed in Fig. 30 to Fig. 32
are further described in Appendix B.
An ‘x’ symbol in a register bit location
indicates that that bit is not used by the
ALC. These unused bits should be
written to ‘0’ when writing to the register
and will return ’1’ when reading the
register.
All the ALC write registers are initialised
to 0 after power–up.
MB86687A APPENDICESEdition 2.0
53
Fig. 30 – ALC REGISTER MAP (1 of 3)
ADDRESS FUNCTION
0
1
2
3
TRANSMIT DESCRIPT OR TABLE BASE ADDRESS REGISTER
CIRCUIT REFERENCE TABLE BASE ADDRESS REGISTER
TRANSMIT QUEUE BASE ADDRESS REGISTER
TRANSMIT PENDING QUEUE START ADDRESS REGISTER
5
6
TRANSMIT PENDING QUEUE WRITE POINTER
7TRANSMIT BUFFER RELEASE QUEUE START ADDRESS REG.
9
10
11
12
13
14
15
16
17
TRANSMIT BUFFER RELEASE QUEUE WRITE POINTER
8TRANSMIT BUFFER RELEASE QUEUE END ADDRESS REG.
18
19
4TRANSMIT PENDING QUEUE END ADDRESS REGISTER
MODE REGISTER
CONTROL REGISTER
DMA MODE REGISTER
RESERVED
DMA BURST REGISTER
GFC/CI STATUS CHANGE REGISTER
TRANSMIT PENDING QUEUE READ POINTER
TRANSMIT BUFFER RELEASE QUEUE READ POINTER
RESERVED
INTERRUPT STATUS REGISTER
INTERRUPT MASK REGISTER
–––
–––
R/O
TYPE
W / O
CW / R
CW / R
W / O
W / O
W / O
W / O
W / O
W / O
W / O
W / O
W / O
W / O
W/R
R / O
Fig. 34
Fig. 35
Fig. 36
Fig. 33
Fig. 33
Fig. 39
Fig. 41
Fig. 43
Fig. 44
Fig. 45
Fig. 46
Fig. 47
W/R
REF
Fig. 33
W/R
Fig. 34
Fig. 34
Fig. 35
Fig. 35
Fig. 36
Fig. 36
Fig. 37
Edition 2.0MB86687A APPENDICES
54
Fig. 31 – ALC REGISTER MAP (2 of 3)
ADDRESS FUNCTION
20
21
22
23
25
26
27
29
30
31
32
33
34
35
ALC A VERAGE CELL TRANSMISSION RA TE REGISTER
ALC LEAKY BUCKET CAPACITY REGISTER
36
37
RESERVED
28
TRANSMIT QUEUE SERVICE ENABLE REGISTER
38
39
24
ALC PEAK CELL TRANSMISSION RATE REGISTER
RESERVED
RESERVED
RESERVED–––
–––
–––
–––
TYPE
W / O
W / O
W / O
W / O
W / O
W / O
W / O
W / O
W / O
W / O
W / O
W / O
W / O
W / O
W / O
W / O
TRANSMIT QUEUE SERVICE RATE REGISTER LOW 1
TRANSMIT QUEUE SERVICE RATE REGISTER LOW 2
TRANSMIT QUEUE SERVICE RATE REGISTER LOW 3
TRANSMIT QUEUE SERVICE RATE REGISTER LOW 4
TRANSMIT QUEUE SERVICE RATE REGISTER MEDIUM 1
TRANSMIT QUEUE SERVICE RATE REGISTER MEDIUM 2
TRANSMIT QUEUE SERVICE RATE REGISTER MEDIUM 3
TRANSMIT QUEUE SERVICE RATE REGISTER MEDIUM 4
TRANSMIT QUEUE SERVICE RATE REGISTER HIGH 1
TRANSMIT QUEUE SERVICE RATE REGISTER HIGH 2
TRANSMIT QUEUE SERVICE RATE REGISTER HIGH 3
TRANSMIT QUEUE SERVICE RATE REGISTER HIGH 4
Fig. 47
Fig. 48
Fig. 49
Fig. 50
REF
Fig. 47
Fig. 47
Fig. 47
Fig. 47
Fig. 47
Fig. 47
Fig. 47
Fig. 47
Fig. 47
Fig. 47
Fig. 47
Fig. 49
(T)
(T)
(T)
(T)
(T)
(T)
(T)
(T)
(T)
(T)
(T)
(T)
(T)
(T)
(T)
(T)
MB86687A APPENDICESEdition 2.0
55
Fig. 32 – ALC REGISTER MAP (3 of 3)
ADDRESS FUNCTION
40
41
42
43 RECEIVE BUFFER FREE QUEUE WRITE POINTER
RECEIVE BUFFER FREE QUEUE START ADDRESS REGISTER
45
46
47
49
50
RECEIVE DESCRIPTOR BASE ADDRESS REGISTER
51
52
53
54
55
RECEIVE BUFFER READY QUEUE WRITE POINTER
56
57
48
RECEIVE BUFFER READY QUEUE END ADDRESS REGISTER
58
59
RECEIVE BUFFER READY QUEUE STAR T ADDRESS REGISTER
44
RECEIVE BUFFER FREE QUEUE END ADDRESS REGISTER
HOST RECEIVE DESCRIPT OR / STATUS TABLE READ REG.
RECEIVE BUFFER READY QUEUE READ POINTER
RECEIVE BUFFER FREE QUEUE READ POINTER
RECEIVE BUFFER TIME OUT COUNTER PERIOD REGISTER
DROPPED CELL COUNTER
RECEIVE BUFFER TIME OUT INTER VAL REGISTER
DROPPED PACKET COUNTER
W / O
W / O
W / O
RECEIVE ADDRESS FILTER REGISTER
CW / R
W / O
W / O
W / O
CW / R
W / O
W / O
R / O
W / O
R / O
W / R
W / O
R / O
RECEIVE QUEUE BASE ADDRESS REGISTER
RECEIVED BUFFER READY DATA HOLD REGISTER
MAXIMUM RECEIVED PACKET LENGTH REGISTER
TYPE
R / O
W / O
HOST RECEIVE DESCRIPT OR / STATUS TABLE WRITE REG.
HOST RECEIVE DESCRIPT OR / STATUS TABLE ACCESS REG.
Fig. 51
Fig. 52
Fig. 53
Fig. 54
Fig. 55
Fig. 56
Fig. 57
Fig. 58
Fig. 59
W/R
REF
W/R
Fig. 51
Fig. 51
Fig. 52
Fig. 52
Fig. 53
Fig. 54
Fig. 54
Fig. 55
Fig. 56
Fig. 56
Fig. 58
Edition 2.0MB86687A APPENDICES
56
B. REGISTER MAPS
Fig. 33 – REGISTERS 0, 1 AND 2
Register 0 – Transmit Descriptor Table Base Address Register
Register 1 – Circuit Reference Table Base Address Register
This base address (shifted left by 8 bits) is added to the 12 bit Transmit Descriptor
address (shifted left by 5 bits) from the Transmit Pending or Release Queue to obtain
the full 24 bit address of the Transmit Descriptor required to execute a packet
transmission.
This base address (shifted left by 8 bits) is added to the 10 bit circuit reference address
(shifted left by 4 bits) from the Transmit Descriptor to obtain the full 24 bit address of the
Circuit Reference Table entry describing the circuit to be used when executing the
requested transmission.
Register 2 – Transmit Queue Base Address Register
XXXX00
TQA0TQA1TQA2TQA3TQA4TQA5TQA6
This register contains the upper10 bits of both the Transmit Pending and Buffer Release
Queue addresses. This base address is concatenated with the start or end address
(shifted left by 1 bit) or with the write or read pointers (shifted left by 1 bit) to obtain the
upper 23 bits of the system or dual port SAR memory address of the Pending or
Release Queue entry. Address bit 0 is always set to 0 by the ALC.
TDA15
TDA7
TDA14
TDA6
TDA13
TDA5
TDA12
TDA4
TDA11
TDA3
TDA10
TDA2
TDA9
TDA1
TDA8
TDA0
CRA15
CRA7
CRA14
CRA6
CRA13
CRA5
CRA12
CRA4
CRA11
CRA3
CRA10
CRA2
CRA9
CRA1
CRA8
CRA0
D0
D15
D0
D15
D0
D15
TQA7
TQA9 TQA8
MB86687A APPENDICESEdition 2.0
57
Fig. 34 – REGISTER 3, 4 AND 5
Register 3 – Transmit Pending Queue Start Address Register
TPS8TPS9TPS10TPS11TPS12XX
TPS0TPS1TPS2TPS3TPS4TPS5TPS6TPS7
Register 4 – Transmit Pending Queue End Address Register
TPE8TPE9TPE10TPE11TPE12XXX
TPE0TPE1TPE2TPE3TPE4TPE5TPE6TPE7
This offset address is shifted left by one bit and concatenated to the Transmit
Queue Base Address Register contents (shifted left by 14 bits) to obtain the
upper 23 bits of the Transmit Pending Queue end address. This end address
indicates the finish of the Transmit Pending Queue space which is used to pass
transmit request buffer descriptor addresses from the Host to the ALC. Address
bit 0 is always set to 0 by the ALC.
This offset address is shifted left by one bit and concatenated to the Transmit
Queue Base Address Register contents (shifted left by 14 bits) to obtain the upper
23 bits of the Transmit Pending Queue start address. This start address indicates
the beginning of the Transmit Pending Queue space which is used to pass
transmit request buffer descriptor addresses from the Host to the ALC. Address
bit 0 is always be set to 0 by the ALC.
Register 5 – Transmit Pending Queue Write Pointer
TPW8TPW9TPW10TPW11TPW12FULLEMPTYINCWRAP
TPW0TPW1TPW2TPW3TPW4TPW5TPW6TPW7
This offset address is shifted left by 1 bit and concatenated to the Transmit Queue
Base Address Register contents (shifted left by 14 bits) to obtain the upper 23 bits of
the Transmit Pending Queue write pointer. The Host uses this pointer when entering
transmit requests by writing a transmit descriptor reference address to the transmit
pending queue. Address bit 0 is always be set to 0 by the ALC.
X
D0
D15
D0
D15
D0
D15
INCWRAP When writing to the host–controlled queue registers, if the most
significant bit of the control data bus is set, the ALC will
automatically increment its internal copy of the pointer being
written to regardless of the pointer value specified on the data bus.
EMPTY If this bit is set, it indicates that the ALC’s pointer for the queue is
at the same value as the host pointer’s value returned by the read
and that the queue is empty.
FULL If this bit is set, it indicates that the host pointer and ALC pointer
values are the same and that the queue is full.
Edition 2.0MB86687A APPENDICES
58
Fig. 35 – REGISTER 6, 7 AND 8
TPR8TPR9TPR10TPR11TPR12ASYNCIXX
TPR0TPR1TPR2TPR3TPR4TPR5TPR6TPR7
Register 6 – Transmit Pending Queue Read Pointer
This offset address is shifted left by 1 bit and concatenated to the Transmit Queue
Base Address Register contents ( shifted left by 14 bits ) to obtain the upper 23 bits
of the Transmit Pending Queue read pointer. The ALC uses this pointer when
retrieving transmit requests by reading a transmit descriptor reference address
from the Transmit Pending Queue. Address bit 0 is always set to 0 by the ALC.
Register 7 – Buffer Release Queue Start Address Register
BRS8X
BRS0BRS7
Register 8 – Buffer Release Queue End Address Register
BRS1BRS2BRS3BRS4BRS5BRS6
BRS9BRS10BRS11BRS12XX
BRE0BRE7 BRE1BRE2BRE3BRE4BRE5BRE6
BRE8X BRE9BRE10BRE11BRE12XX
This offset address shifted left by 1 bit is concatenated to the Transmit Queue Base
Address Register contents (shifted left by 14 bits ) to obtain the upper 23 bits of the
Transmit Release Queue start address. This start address indicates the beginning of
the Transmit Release Queue space used by the ALC to indicate the availability of free
transmit descriptors to the host. Address 0 is always set to 0.
This offset address shifted left by 1 bit is concatenated to the Transmit Queue Base
Address Register contents (shifted left by 14 bits ) to obtain the upper 23 bits of the
Transmit Release Queue end address. This end address indicates the finish of the
Transmit Release Queue space used by the ALC to indicate the availability of free
transmit descriptors to the host. Address 0 is always set to 0.
D0
D15
D0
D15
D0
D15
ASYNCI When set this indicates value was changing during an
asynchronous microprocessor read. Since this means an incorrect
transitional value may have been recorded the register should be
re–read.
MB86687A APPENDICESEdition 2.0
59
BRW8X
BRW0BRW7 BRW1BRW2BRW3BRW4BRW5BRW6
BRW9BRW10BRW11BRW12ASYNCIX
Register 9 – Buffer Release Queue Write Pointer
Register 10 – Buffer Release Queue Read Pointer
BRR8INCWRAP BRR9BRR10BRR11BRR12FULLEMPTY
This offset address is shifted left by one bit and concatenated to the Transmit Queue
Base Address Register contents (shifted left by 14 bits ) to obtain the upper 23 bits of
the Transmit Buffer Release Queue write pointer. The ALC uses this pointer when a
packet transmission has been completed to return the transmit descriptor used to the
pool of free transmit descriptors for use by the host in future transmit requests.
Please refer to Register 6 on page 58 for a description of ASYNCI.
This offset address is shifted left by one bit and concatenated to the Transmit Queue
Base Address Register contents (shifted left by 14 bits) to obtain the upper 23 bits of
the Transmit Buffer Release Queue read pointer. The Host uses this read pointer to
obtain an available transmit descriptor when a packet is ready for transmission.
Fig. 36 – REGISTERS 9 and 10
D0
D15
D0
D15
BRR0BRR1BRR2BRR3BRR4BRR5BRR6BRR7
INCWRAP When writing to the host–controlled queue registers, if the most
significant bit of the control data bus is set, the ALC will
automatically increment its internal copy of the pointer being
written to regardless of the pointer value specified on the data bus.
EMPTY If this bit is set, it indicates that the ALC’s pointer for the queue is
at the same value as the host pointer’s value returned by the read
and that the queue is empty.
FULL If this bit is set, it indicates that the host pointer and ALC pointer
values are the same and that the queue is full.
Edition 2.0MB86687A APPENDICES
60
Register 13 – CE/GFC Change Indication
RCR9–0: Receive Circuit Reference of circuit with changed status.
Fig. 37 – REGISTER 13
D0
D15 X CE GFC3 GFC2 RCR9GFC0GFC1
CE: Status of Congestion Experienced Bit.
GFC3–0: Status of GFC Field (UNI mode only).
RCR8
RCR7 RCR6 RCR5 RCR4 RCR3 RCR2 RCR1 RCR0
This register shows the status of the latest change in congestion experienced and
GFC status with its associated Receive Circuit Reference.
MB86687A APPENDICESEdition 2.0
61
Register 14 – DMA Burst Length Register
DBL7–DBL0: This register may be set to limit the maximum number of ALC,
system memory DMA access cycles that may occur in a single
block. This burst length is applicable only when the ALC is
operating in ready dependent, DMA mode.
A burst length limit of 0 indicates unlimited burst length.
A burst length limit in the range 1 – 255 indicates the maximum
number of ALC DMA cycles that can occur before the bus is
released to allow re-arbitration for control of the system bus.
Fig. 38 – REGISTER 14
DBL7 DBL1DBL2DBL6 DBL4DBL5 DBL0DBL3 D0
D15 RIF3 RIF2 RIF1 RIF0 TIF0TIF1TIF2TIF3
RIF3–RIF0: Receive Buffer Ready Interrupt Frequency.
This count specifies the frequency of receive buffer ready
interrupts.
This value specifies the number of received buffers that are
completed before the ALC generates a service request to the
host using the Receive Buffer Ready Queue Write interrupt.
TIF3–TIF0: Transmit Buffer Release Interrupt Frequency.
This count specifies the frequency of transmit buffer release
interrupts.
This value specifies the number of transmitted buffers that are
completed with the IOC bit set before the ALC generates a
service request to the host using the Receive Buffer Ready
Queue Write interrupt.
Edition 2.0MB86687A APPENDICES
62
Fig. 39 – REGISTER 15
Register 15 – DMA Mode Register
STEALDSTEALODMAOPTBURSTDBRSTOSCEPARSELSBL
WMOD BMODE1ORDERRMOD CMODE BMODE0MMODE
BURSTO: Burst Overhead. If this bit is set then the ALC will finish all control
transfers for transmit before switching over to receive and vice
versa.
SYN
SBL: Single Cycle Burst Length. This selects between 8–transfer (set)
and 4–transfer (cleared) data bursts.
BURSTD: Burst Data. If this bit is set then the ALC will finish all data
transfers for transmit before switching over to receive and vice
versa.
SCE: Single Cycle Enable. This bit is set to enable single clock cycle
burst data transfers
PARSEL: Parity Select. This bit is set for odd parity and cleared for even
parity.
D0
D15
DMAOPT: DMA Optimise. Setting ths bit will cause the ALC to optimise the
dead cycles between overhead operations.
STEALO: Steal Overhead. If this bit is set then the ALC will allow transmit to
steal overhead cycles from receive and vice versa.
STEALD: Steal Data. If this bit is set then the ALC will allow transmit to
steal data cycles from receive and vice versa.
Note: Please refer to section 3.7.3 for an explanation of the setting
of the BURST and STEAL bits.
MB86687A APPENDICESEdition 2.0
63
Fig. 40 – REGISTER 15 contd.
Register 15 – DMA Mode Register (Continued)
STEALDSTEALODMAOPTBURSTDBRSTOSCEPARSELSBL
WMOD BMODE1ORDERRMOD CMODE BMODE0MMODE
ORDER: SAR Memory Byte Ordering Convention.
This bit is cleared to select Big Endian (Motorola/SPARC) byte
ordering and set to select Little Endian (Intel/DEC Alpha) byte
ordering. This byte ordering applies to the transmit and receive
buffer data and selected Endian word ordering applies to the queue
structures Descriptor data uses the Little Endian ordering convention.
The queue data format is configurable as Big Endian or Little Endian,
using word swapping.
SYN
SYN: 0 DMA treated as asynchronous.
1 DMA treated as synchronous.
BMODE1–0: SAR Memory Control Signal Mode.
00 Intel / GP Timings
01 Intel 486 Timings
10 Motorola Timings
11 Motorola 68x40 timings
MMODE: SAR Memory Mode.
This memory mode bit is set to select dual port RAM use for
segmentation and reassembly and cleared to select DMA use of
system memory for segmentation and reassembly.
CMODE: SAR Memory Cycle Time.
This bit is cleared to select ready dependent SAR memory cycles
(minimum cycle time = 2 x DCCLK) and set to select fast mode SAR
memory cycles (cycle time = 2 x DCCLK).
D0
D15
WMOD: 0 WR signal as MB86686
1 WR signal extended.
RMOD: 0 Data sampled on falling edge of DCLK, RD signal as
MB86686.
1 Data sampled on rising edge RD signal extended.
Edition 2.0MB86687A APPENDICES
64
Fig. 41 – REGISTER 16
Register 16 – Control Register
SRSTINIT CWRE
DCOAMUNSELAF16AF17
RSTRTTSTLP MAAL5L
VPB2–0: Virual Path Detect bits (Valid range 000 – 101). These are used to
control how many bits of the VP are used in the receive address
mapping.
AF17–16: Address Filter Bits 17 –16. These are the 2 msbs of the receive
address filter. For a full description of this function see section
3.5.9.
UNSEL: UNI/NNI Select. If set this bit uses an NNI address for filtering
(uses all 18 bits of Address Filter). If it is cleared it uses a UNI
address for filtering (used only 14 lsbs of the Address Filter)
MBRQE VPB2 VPB1 VPB0
D0
D15
OAMCRC RDAU
DCOAM: Discard OAM. If this bit is set the ALC will discard all cells
received (excepting F4 cells) which are not user data cells.
MBRQE: Enable Buffer Ready Queue Interrupt when M=0. When in
streaming mode setting this bit will cause a buffer ready queue
interrupt to occur every time a packet is terminated (M=0)
irrespective of the setting of the receive buffer Interupt frequency.
MB86687A APPENDICESEdition 2.0
65
Fig. 42 – REGISTER 16 contd.
Register 16 – Control Register (Continued)
SRSTINIT CWRE
DCOAMUNSEL
RSTRTTSTLP MAAL5L
TSTLP: Test Loop Enable.
When this bit is set the ALC’s transmit cell stream interface is
internally looped back into the receive cell stream interface using
TXCLK.
RSTRT: ALC Cell Stream Interface Daisy Chain Restart.
When this bit is set a daisy chain token pulse is generated on
ALC’s TOUT line. This is used to restart the token daisy chain
if the token has been lost.
CWRE: ALC Host Queue Pointer Initialisation Enable.
This bit is set to allow the Host to initialise the Transmit Pending
Queue Read Pointer, the Transmit Buffer Release Queue Write
Pointer, the Receive Buffer Free Queue Read Pointer and the
Receive Buffer Ready Queue Write Pointer.
This bit should be cleared after initialisation for normal operation.
INIT: Host Initialisation Complete.
This bit is set by the Host when it (the host) has completed all
required initialisation of ALC registers and memory structures.
SRST: ALC Software Reset.
This bit is set to reset all internal ALC circuitry.
MBRQE VPB0 VPB1 VPB2
D0
D15
OAMCRC RDAU
RDAU: Receive Descriptor Auto Update of Remaining Capacity. Setting
this bit enables automatic initialisation of the bytes remaining field
in the Receive Descriptor with the Buffer Size field and automatic
clearing of the Bytes Received field.
MAAL5L: Maintain AAL5 Length. Setting this bit will cause the ALC to
automatically compute the AAL5 length field across multiple
chained or streamed transmit buffers.
OAMCRC: OAM CRC checking. This bit should be set to enable CRC–10
checking on all non–user data cells excepting F4 cells.
AF17 AF16
Edition 2.0MB86687A APPENDICES
66
Fig. 43 – REGISTER 17
Register 17 – Mode Register
RIDDMASKDCHAINSMODEBCHAIN
HEC0HEC1HEC2VPFBASAMTRTL0TRTL1
TRTL1 – TRTL0: Transmit Routing Tag Length.
This field specifies the length (if any) of routing tag to be
appended to all transmitted cells.
00: No Routing Tag
01: One Octet Routing Tag
10: Two Octet Routing Tag
11: Three Octet Routing Tag.
AM: Traffic Rate Averaging Method.
This bit is cleared to select the single leaky bucket (trickle) method
of traffic rate averaging and set to select the double leaky bucket
(burst) method. The method chosen applies to averaging for each
individual virtual circuit and also for the total ALC output traffic.
BAS: Buffer Ageing Support.
This bit is set to support receive buffer ageing. For a full description of
this function, please refer to section 3.1.6.
VPF: Virtual Path Filter Enable.
If this bit is set then only incoming cells whose VPI matches the
value specified in the Receive Address Filter Register are processed.
If this bit is cleared then the incoming VPI value is ignored.
HEC2 – HEC0: Header Error Check Operation.
Cell header error check mask byte value.
HEC2 = 0 Mask = 0x55.
HEC2 = 1 Mask = 0x00.
HEC1 = 0 Transmitted cell header check octet included
( 53 byte cell ).
HEC1 = 1 Transmitted cell header check octet omitted
(52 byte cell ).
HEC0 = 0 Cell header error checking enabled.
HEC0 = 1 Cell header error checking disabled.
D0
D15
0 RTL1 RTL0
MB86687A APPENDICESEdition 2.0
67
BCHAIN: Receive Buffer Chaining Mode Enable
Set to enable chaining mode whereby a single packet may be
located in different reassembly buffers each described by a different
descriptor but linked using pointers into a single chain.
Cleared to disable buffer chaining.
SMODE: Receive Streaming Mode Enable
Set to enable ALC streaming mode whereby processing of large
received packets can begin before all the packet data is available.
Cleared to disable streaming mode.
DCHAIN: Transmit Cell Stream Daisy Chain Enable
Set to allow multiple ALC devices to share a single network
interface device by using token passing. Cleared if using a single
ALC device per network interface device.
DMASK: Disable Transmit Queue Masking
Set to disable automatic service request masking from medium
and low priority queues when the total ALC data rate limit is
exceeded. Cleared to enable masking.
ie. DMASK = 0 High Queue Enabled Only
DMASK = 1 Low, Medium and High Queues Enabled
RTL1–RTL0: Receive Routing Tag Length
This field specifies the length (if any) of routing tag expected to be
appended to received cells.
00: No Routing Tag
01: One Octet Routing Tag
10: Two Octet Routing Tag
11: Three Octet Routing Tag.
RID: Reassembly ID Select (applies to entire receive side of the ALC)
RID = 0: VCI is used for addressing.
RID = 1: MID field is used for addressing.
Fig. 44 – REGISTER 17 (continued)
RIDDMASKDCHAINSMODEBCHAIN
HEC0HEC1HEC2VPFBASAMTRTL0TRTL1
Register 17 – Mode Register (continued)
D0
D15
RTL1 RTL00
Edition 2.0MB86687A APPENDICES
68
Fig. 45 – REGISTER 18
Register 18 – Interrupt Status / Service Register
TAC: Receive Status / Descriptor Table Access Complete.
Set when the host read or write access to the receive status/
descriptor table as requested through register 59 has completed.
RFE: Receive Buffer Free Queue Empty.
Set if no receive buffer descriptors are available for ALC use. Host
must service previously received packets.
TRF: Transmit Buffer Release Queue Full.
Set if the last available location in the transmit buffer release
queue has been used by the ALC. The host must respond to
previously completed transmissions by reading the transmit release
queue entries.
RRFL: Receive Buffer Ready Queue Write Fail.
Set if the ALC attempts to write to an already full receive buffer ready
queue. The host must service previously received packets.
RRW: Receive Buffer Ready Queue Write.
Set when the ALC has completed reception of a packet (or number of
packets – see register 16). Host must acknowledge reception by reading
the associated receive buffer ready queue entry.
RRFU: Receive Buffer Ready Queue Full.
Set when the receive buffer ready queue is full. The host must service
previously received packets.
INIT: Initialisation Complete.
Set when the ALC internal initialisation is complete.
TRW: Transmit Buffer Release Queue Write.
Set when the ALC has completed the requested packet transmission.
Host should acknowledge this by reading the corresponding release
queue entry.
On detection of an interrupt condition the ALC sets an interrupt flag in this register.
If the corresponding interrupt mask bit in Register 19 is set then the ALC activates
the output interrupt pin. The host processor may determine the interrupt cause by
reading this register. An interrupt is cleared and disabled by writing a ”1” to the
associated bit and re–enabled by writing a ”0”.
INITRRFUTRFRFE RRFLTAC TRW RRW
BUSERRSRCOMRRCOMDTCOMGFCCCECPARERRX
D0
D15
MB86687A APPENDICESEdition 2.0
69
Fig. 46 – REGISTER 18 (continued) and 19
Register 18 – Interrupt Status Register (continued)
RRCOM: Receive RAM Test Complete.
Set by the ALC to indicate that the ALC’s internal receive scratch pad
memory test has completed.
SRCOM: Send RAM Test Complete.
Set by the ALC to indicate that the ALC’s internal transmit scratch pad
memory test has completed.
Register 19 – Interrupt Mask Register
1 = Interrupt generation enabled
This interrupt mask register contains one bit for each possible interrupt source as
described for the Interrupt Status Register 18. above. Each interrupt condition can be
enabled to activate the ALC’s output interrupt signal by setting the corresponding interrupt
mask bit in this register. Likewise each interrupt source can be prevented from activating
the external interrupt pin by clearing the corresponding bit in this register.
For each mask location:
0 = Interrupt generation masked.
1 = Interrupt generation enabled.
INITRRFUTRFRFE RRFLTAC TRW RRW
BUSERRSRCOMRRCOMCECPARERRX
D0
D15
DTCOM: Descriptor Table Test Complete.
Set by the ALC to indicate that the ALC’s internal RSD
memory test has completed.
PARERR: .
DTCOMGFCC
CEC: Congestion Experienced Change. Circuit Changed in register 13
GFCC: GFC Field Change (UNI Mode only). Circuit changed in register 13
Parity Error on DMA Interface
In addition this register, when read indictes the revision of the MB86687A. This is set to
0xXX01h.
BUSERR Set by the ALC in Fast Mode when host activates the DTACK/READY
input to indicate a bus error
These three fields are used only during the manufacturing phase.
Edition 2.0MB86687A APPENDICES
70
Fig. 47 – REGISTERS 20 to 31
Registers 20 to 31 – Transmit Queue Service Rate Registers
SC0SC1XXXXX
SR0SR1SR2SR3SR4SR5SR6SR7
X
L
SCP
Note: The maximum value which SR0 – SR7 can take is given by:
Where L is cell width in nano-seconds, SCP the selected counter
period integer multiple of the system clock period.
This maximum value corresponds to a single active Virtual Circuit
using the total link capacity.
D0
D15
The Service Rate counters are used to implement leaky bucket traffic management on
each of the ALC’s 12 peak rate queues. Bits SR7 – SR0 are used to specify the rate at
which tokens are removed from the leaky buckets of each circuit associated with that
queue. In single leaky bucket mode this value determines the rate of cell transmission
during the initial burst. In double leaky bucket mode this value determines the rate of cell
transmission in each burst.
The counter value specified is decremented using a scaled version of the input
transmission clock (TCLK). TCLK is divided by the scaling factor specified in bits SC0
and SC1 of this register as shown below. Each time the counter reaches zero it is
reloaded to its initial value.
SC1 SC0 Scaling Factor
0 0 4
0 1 16
1 0 64
1 1 256
Register 20 = LP1
Register 31 = HP4
MB86687A APPENDICESEdition 2.0
71
Fig. 48 – REGISTER 32
Register 32 – Transmit Queue Service Enable Register
ENM2ENM1ENL3
ENAP
XX ENL1 ENL2
ENH4ENH3ENH2ENH1ENM4ENM3
ENL4
Servicing of each of the 12 available transmission descriptor queues can be enabled by
setting and disabled by clearing their respective peak cell transmission rate counter enables
as shown below. Also the total ALC peak and average rate counters can be individually
enabled by setting and disabled by clearing the ENAP and ENAA bits respectively.
Low Priority Transmit Queue Service Enables:
ENL1: Enable counter for low priority service queue 1
ENL2: Enable counter for low priority service queue 2
ENL3: Enable counter for low priority service queue 3
ENL4: Enable counter for low priority service queue 4
Medium Priority Transmit Queue Service Enables:
ENM1: Enable counter for medium priority service queue 1
ENM2: Enable counter for medium priority service queue 2
ENM3: Enable counter for medium priority service queue 3
ENM4: Enable counter for medium priority service queue 4
High Priority Transmit Queue Service Enables:
ENH1: Enable counter for high priority service queue 1
ENH2: Enable counter for high priority service queue 2
ENH3: Enable counter for high priority service queue 3
ENH4: Enable counter for high priority service queue 4
Total ALC Traffic Management Counter Enables:
ENAP: Enable counter for ALC peak transmission rate.
ENAA: Enable counter for ALC average transmission rate.
ENAA
D0
D15
Edition 2.0MB86687A APPENDICES
72
Fig. 49 – REGISTER 33 AND 34
Register 33 – ALC Peak Cell Transmission Rate Register
PS0PS1XXXXX
PR0PR1PR2PR3PR4PR5PR6PR7
X
Register 34 – ALC Average Cell Transmission Rate Register
AS0AS1XXXXXX
AR0AR1AR2AR3AR4AR5AR6AR7
This total ALC output peak rate counter is used to implement leaky bucket traffic
management on the ALC’s transmitted cell stream. Bits PR7 – PR0 are used to specify
the rate at which tokens are removed from the leaky bucket. In single leaky bucket
mode this value determines the rate of cell transmission during the initial burst. In double
leaky bucket mode this value determines the rate of cell transmission in each burst.
The counter value specified is decremented using a scaled version of the input
transmission clock (TCLK). TCLK is divided by the scaling factor specified in bits PS0
and PS1 of this register as shown below. Each time the counter reaches zero it is
reloaded to its initial value.
PS1 PS0 Scaling Factor
0 0 1
0 1 2
1 0 4
1 1 8
This total ALC output average rate counter is used to implement leaky bucket traffic
management on the ALC’s transmitted cell stream. Bits AR7 – AR0 are used to specify
the rate at which tokens are removed from the leaky bucket. In single leaky bucket
mode this value determines the rate of cell transmission during the initial burst. In double
leaky bucket mode this value determines the length of time that the output cell stream is
idle between bursts.
The counter value specified is decremented using a scaled version of the input
transmission clock (TCLK). TCLK is divided by the scaling factor specified in bits AS0
and AS1 of this register as shown below. Each time the counter reaches zero it is
reloaded to its initial value.
AS1 AS0 Scaling Factor
0 0 1
0 1 2
1 0 4
1 1 8
D0
D15
D0
D15
MB86687A APPENDICESEdition 2.0
73
Fig. 50 – REGISTER 35
Register 35 – ALC Leaky Bucket Capacity Register
XXXXXX
LBC0LBC1LBC2LBC3LBC4LBC5LBC6LBC7
XX
Note:
If the resulting value of M is not a positive integer then in the single leaky bucket
method it should be rounded DOWN to the nearest positive integer and in the
double leaky bucket method it should be rounded UP to the next positive integer.
In this case a minimum allowed value of B is specified for each selected U.
U = 0.875 minimum B = 9.
U = 0.75 minimum B = 5
U = 0.625 minimum B = 4
All other values of U minimum B = 3.
D0
D15
This register specifies the number of tokens held in the ALC total traffic
management leaky bucket. This parameter together with the ALC peak transmission
rate register setting and the ALC average transmission rate register setting
determines the total cell transmission rate at the ALC’s output.
This capacity value can be used together with the ALC peak cell rate and average
cell rate to calculate the maximum burst length of transmitted cells generated by the
ALC.
For Single Leaky Bucket Mode:
M = (B–1) x (1–U) Note that M 0
For Double Leaky Bucket Mode:
M = B x (1–U)
B = maximum number of cells in the output burst.
M = leaky bucket capacity as specified in LBC7 – LBC0
U = utilisation = average cell output rate / peak cell output rate
= (AR7 – AR0) / (PR7 – PR0)
Edition 2.0MB86687A APPENDICES
74
Register 40 – Receive Queue Base Address Register
RQA0RQA1RQA2RQA3RQA4RQA5RQA6RQA7
Fig. 51 – REGISTERS 40 and 41
NAM SIFC ADCCK ARXCLK DMID X RQA9 RQA8
D0
D15
This register contains the upper10 bits of both the Recieve Buffer Free Queue and
Buffer Ready Queue addresses. This base address is concatenated with the start or
end address (shifted left by 1 bit) or with the write or read pointers (shifted left by 1
bit) to obtain the upper 23 bits of the system or dual port SAR memory address of the
Pending or Release Queue entry. Address bit 0 is always set to 0 by the ALC.
NAM: Non Assured Mode – If set the ALC receive will dma out to
system memory the AAL5 SAR payload within the trailer
cell even if the packet CRC32 check fails.
SIFC: Streaming Interrupt First Cell – If set, after writing out the
payload from the first cell of a packet the ALC will write the
receive descriptor to the RBRQ and generate an RRW interrupt.
ADCCK: Set if microprocessor reads are asynchronous to DCCK.
ARXCLK: Set if microprocessor reads are asynchronous to RXCLK.
DMID: For AAL3/4 receive traffic. If set, the ALC will not discard
cells with non–zero MID fields.
Register 41 – Receive Buffer Free Queue Start Address Register
RBFS8RBFS9RBFS10RBFS11RBFS12XXX
RBFS0RBFS1RBFS2RBFS3RBFS4RBFS5RBFS6RBFS7 D0
D15
This offset address is shifted left by one bit and concatenated to the Recieve Queue
Base Address Register contents (shifted left by 14 bits) to obtain the upper 23 bits of
the Recieve Pending Queue start address. This start address indicates the beginning
of the Recieve Pending Queue space which is used to pass recieve request buffer
descriptor addresses from the Host to the ALC. Address bit 0 is always be set to 0 by
the ALC.
MB86687A APPENDICESEdition 2.0
75
Fig. 52 – REGISTER 42, 43 AND 44
Register 42 – Receive Buffer Free Queue End Address Register
RBFE0RBFE1RBFE2RBFE3RBFE4RBFE5RBFE6RBFE7
RBFE8RBFE9RBFE10RBFE11RBFE12XXX
Register 43 – Receive Buffer Free Queue Write Pointer
RBFW8RBFW9RBFW10RBFW11RBFW12FULLEMPTYINCWRAP
RBFW0RBFW1RBFW2RBFW3RBFW4RBFW5RBFW6RBFW7
D0
D15
D0
D15
This offset address is shifted left by one bit and concatenated to the Recieve Queue
Base Address Register contents (shifted left by 14 bits) to obtain the upper 23 bits of
the Recieve Pending Queue end address. This end address indicates the finish of
the Receive Pending Queue space which is used to pass Receive request buffer
descriptor addresses from the Host to the ALC. Address bit 0 is always set to 0 by
the ALC.
This offset address is shifted left by 1 bit and concatenated to the Receive Queue Base
Address Register contents (shifted left by 14 bits) to obtain the upper 23 bits of the
Receive Pending Queue write pointer. The Host uses this pointer when entering Receive
requests by writing a receive descriptor reference address to the Receive pending queue.
Address bit 0 is always be set to 0 by the ALC.
INCWRAP When writing to the host–controlled queue registers, if the most
significant bit of the control data bus is set, the ALC will
automatically increment its internal copy of the pointer being
written to regardless of the pointer value specified on the data bus.
EMPTY If this bit is set, it indicates that the ALC’s pointer for the queue is
at the same value as the host pointer’s value returned by the read
and that the queue is empty.
FULL If this bit is set, it indicates that the host pointer and ALC pointer
values are the same and that the queue is full.
Register 44 – Receive Buffer Free Queue Read Pointer
RBFR0RBFR1RBFR2RBFR3RBFR4RBFR5RBFR6RBFR7
RBFR8RBFR9RBFR10RBFR11RBFR12ASYNCIXX
D0
D15
This offset address is shifted left by 1 bit and concatenated to the Receive Queue
Base Address Register contents ( shifted left by 14 bits ) to obtain the upper 23 bits
of the Receive Pending Queue read pointer. The ALC uses this pointer when
retrieving transmit requests by reading a receive descriptor reference address from
the Receive Pending Queue. Address bit 0 is always set to 0 by the ALC.
Please refer to Register 6 on page 58 for a description of ASYNCI.
Edition 2.0MB86687A APPENDICES
76
Fig. 53 – REGISTER 45, 46 AND 47
Register 47 – Receive Buffer Ready Queue End Address Register
RBRE0RBRE1RBRE2RBRE3RBRE4RBRE5RBRE6RBRE7
RBRE8RBRE9RBRE10RBRE11RBRE12XXX
D0
D15
This offset address shifted left by 1 bit is concatenated to the Receive Queue Base
Address Register contents (shifted left by 14 bits ) to obtain the upper 23 bits of the
Receive Release Queue end address. This end address indicates the finish of the
Receive Release Queue space used by the ALC to indicate the availability of free
Receive descriptors to the host. Address 0 is always set to 0.
Register 46 – Receive Buffer Ready Queue Start Address Register
RBRS8RBRS9RBRS10RBRS11RBRS12XXX
RBRS0RBRS1RBRS2RBRS3RBRS4RBRS5RBRS6RBRS7 D0
D15
This offset address shifted left by 1 bit is concatenated to the Receive Queue Base
Address Register contents (shifted left by 14 bits ) to obtain the upper 23 bits of the
Receive Release Queue start address. This start address indicates the beginning of
the Receive Release Queue space used by the ALC to indicate the availability of free
Receive descriptors to the host. Address 0 is always set to 0.
Register 45 – Receive Descriptor Table Base Address Register
This base address (shifted left by 8 bits) is added to the 12 bit receive descriptor address
(shifted left by 5 bits) from the Receive Buffer Ready Queue or Receive Buffer Free queue
entry to obtain the full 24 bit address of the receive descriptors.
D0
D15
RDA0
RDA8
RDA1
RDA9
RDA2
RDA10
RDA3
RDA11
RDA4
RDA12
RDA5
RDA13
RDA6
RDA14
RDA7
RDA15
MB86687A APPENDICESEdition 2.0
77
Fig. 54 – REGISTER 48, 49 AND 50
Register 48 – Receive Buffer Ready Queue Write Pointer
RBRW8
Register 49 – Receive Buffer Ready Queue Read Pointer
RBRR0
RBRW9RBRW10RBRW11RBRW12ASYNCIXX
RBRW0RBRW1RBRW2RBRW3RBRW4RBRW5RBRW6RBRW7
RBRR1RBRR2RBRR3RBRR4RBRR5RBRR6RBRR7
RBRR8RBRR9RBRR10RBRR11RBRR12FULLEMPTYINCWRAP
This offset address is shifted left by 1 bit and concatenated to the Receive Queue Base
Address Register contents (shifted left by 14 bits ) to obtain the upper 23 bits of the
Receive Buffer Ready Queue write pointer. The ALC uses this pointer to write the
address of the Receive Descriptor for a received packet which has been reassembled
and placed in the receive buffer. Address bit 0 is always set to 0.
Please refer to Register 6 on page 58 for a description of ASYNCI.
This offset address is shifted left by 1 bit and concatenated to the Receive Queue
Base Address Register contents (shifted left by 14 bits ) to obtain the upper 23 bits of
the Receive Buffer Ready Queue read pointer. The Host uses this pointer to read the
address of the Receive Descriptor for a received packet which has been reassembled
and placed in the receive buffer. Address bit 0 is always set to 0.
Register 50 – Dropped Packet Counter
DPC0DPC1DPC2DPC3DPC4DPC5DPC6DPC7
DPC8DPC9DPC10DPC11DPC12DPC13DPC14ASYNCI
This counter is incremented each time a received packet is lost due to no receive
buffers being available to start reassembly of the incoming data.
N.B. This register is not cleared when read unlike previous revisions of the ALC.
Please refer to Register 6 on page 58 for a description of ASYNCI.
D0
D15
D0
D15
D0
D15
Edition 2.0MB86687A APPENDICES
78
Fig. 55 – REGISTERS 51 AND 52
Register 51 – Receive Buffer Time Out Counter Period Register
BTC0
Register 52 – Receive Buffer Time Out Counter Interval Register
BTC1BTC2BTC3BTC4BTC5BTC6BTC7
BTC8BTC9BTC10BTC11BTC12BTC13BTC14BTC15
BTI8BTI9BTI10BTI11BTI12BTI13BTI14BTI15
The value in this register represents the number of DCCK clock periods required to
increment the receive buffer ageing time base counter. this value is used to pre scale
the ALC input DCCK clock before clocking the ALC’s time base counter. The time base
counter is used to check for receive buffer time out conditions.
The value written to this register defines the maximum time period allowed between the
arrival of a incoming packet and the host servicing the receive buffer.
If the time required by the host to service received packets exceeds this value then the
Received Buffer Ready Queue Status code of 1100b indicating receive buffer timeout
condition is written to the Receive Buffer Ready Queue entry corresponding to that
channel. The ALC’s time base counter is incremented using the DCCK clock pre-scaled
by the value in the Receive Buffer Time Out Counter Period register as described
above.
BTI0BTI1BTI2BTI3BTI4BTI5BTI6BTI7
D0
D15
D0
D15
MB86687A APPENDICESEdition 2.0
79
Register 53 – Receive Buffer Ready Data Hold Register
DHR0DHR1DHR2DHR3DHR4DHR5DHR6DHR7
DHR8DHR9DHR10DHR11DHR12DHR13DHR14DHR15
This register contains the maximum number of bytes of incoming packet data that can
be received by the ALC. If the length of the received packet exceeds this number then
the ALC will deliver the packet but drop the cells beyond the level programmed.
Register 54 – Maximum Received Packet Length Register
When the ALC receives an incoming packet while only a single location is available in
the Receive Buffer Ready Queue, writing the Receive Buffer entry corresponding to this
packet will cause the generation of the Receive Buffer Ready Queue Full Interrupt . If a
further packet is received after this interrupt but before the host has serviced the
Receive Buffer Ready Queue then no Receive Buffer Ready queue space is available to
hold the packet received indication. In this case the ALC instead writes the Receive
Buffer Ready Queue entry to this Receive Buffer Ready Data Hold Register and
generates the Receive Buffer Ready Queue Write Fail interrupt. Note that if additional
packets are received the value in this register will be overwritten with the most recently
received packet’s Receive Buffer Ready Queue entry data.
D0
D15
D0
D15
MPL0
MPL8
MPL1
MPL9
MPL2
MPL10
MPL3
MPL11
MPL4
MPL12
MPL5
MPL13
MPL6
MPL14
MPL7
MPL15
Fig. 56 – REGISTER 53 AND 54
Edition 2.0MB86687A APPENDICES
80
Fig. 57 – REGISTER 55 AND 56
Register 56 – Receive Address Filter Register
AF9AF15
Address Filter These bits, together with AF17 and AF16 in Register 16, are used
as a filter for those address bits not covered in the 10 bits of the
ALC mapped address.
D0
D15 AF14 AF13 AF12 AF11 AF10 AF8
AF7 AF6 AF5 AF4 AF3 AF2 AF1 AF0
Register 55 – Dropped Cell Counter
This counter value is incremented each time a received cell is dropped by the ALC
due to:
1) Cell received for a packet which the receive has previously aborted due to:
Buffer overflow
No buffers available
No chaining buffers available
Buffer time out
Maximum packet length exceeded
2) EOM/COM received with no BOM (for AAL3/4)
3) CRC10 error (with RID=0 CR17, VCI used for addressing) (for AAL3/4)
4) Non–zero MID (with RID=0 CR17, VCI used for addressing and DMID=0)
(for AAL3/4)
N.B. This register is not cleared when read unlike previous revisions of the ALC.
Please refer to Register 6 on page 58 for a description of ASYNCI.
D0
D15
DCC0
DCC8
DCC1
DCC9
DCC2
DCC10
DCC3
DCC11
DCC4
DCC12
DCC5
DCC13
DCC6
DCC14
DCC7
ASYNCI
MB86687A APPENDICESEdition 2.0
81
Fig. 58 – REGISTER 57 AND 58
Register 57 – Host Receive Descriptor / Status Table Read Register
DSC8DSC9DSC10DSC11
DCRD
RIP
ACT
DP
DSC0DSC1DSC2DSC3DSC4DSC5
DSC6DSC7
This register is used in conjunction with the Host Receive Descriptor / Status Table
Access Register by the host to write Receive Descriptor / Status Table entries.
The host normally accesses this table only during initialisation.
DSC0 – DSC11: Receive descriptor pointer for this Receive Circuit Reference.
DP: Receive descriptor pointer in DSC0 – DSC11 above is valid.
RIP: Set Receive in progress on the Receive Circuit Reference
corresponding to this entry.
ACT: Activate monitoring of the Receive Circuit Reference corresponding
to this entry
DCRD: Discard received packets on the channel referenced by this entry.
Register 58 – Host Receive Descriptor / Status Table Write Register
DSC8DSC9DSC10DSC11
DCRD
RIP
ACT
DP
DSC0DSC1DSC2DSC3DSC4DSC5
DSC6DSC7
D0
D15
D0
D15
This register is used by the host to read the Receive Descriptor / Status Table.
This table specifies the location and status of specific receive channel descriptors.
DSC0 – DSC11: Receive descriptor pointer for this Receive Circuit Reference.
DP: Receive descriptor pointer in DSC0 – DSC11 above is valid.
RIP: Reception in progress on the Receive Circuit Reference
corresponding to this entry.
ACT: Active monitoring of the Receive Circuit Reference corresponding
to this entry.
DCRD: Discard in progress on the channel referenced by this entry.
Edition 2.0MB86687A APPENDICES
82
Fig. 59 – REGISTER 59
Register 59 – Host Receive Descriptor / Status Table Access Register
RESRESAAL TYP1AAL TYP0HOSTR RD/WR
This register is used, together with registers 57 and 58 to gain read and write access to
the ALC’s internal Receive Descriptor / Status Table. The tables need to be accessed
by the host for initialization, scatter/gather mode and emergency buffer recovery.
When the Host Access Request (HOSTR) bit is set and the read/write control (RD/WR)
bit is SET, the contents of register 58 and the AAL Type bits are written to the table
entry at the address indicated by RCR 0:9. The ALC will generate a TAC interrupt to
indicate that the write operation is complete.
When the Host Access Request (HOSTR) bit is set and the read/write control bit
(RD/WR) is CLEARED, the ALC is configured to read the internal Receive
Descriptor / Status Table entry at the address indicated by RCR 0:9. The ALC will
generate a TAC interrupt to indicate that the read operation is complete. At this time
Register 57 will contain the requested table entry contents.
D0
D15
RCR0 –RCR9: This is the Table address Receive Circuit Reference.
AAL TYP: 00 AAL3/4
01 Transparent Mode
10 Transparent Cell Mode
11 AAL5.
HOSTR: Set to 1: Host Access Requested
Cleared to 0: Host Access Completed.
RD/WR: Set to 1: Write Request
Cleared to 0: Read Request.
RCR9 RCR8
RCR7 RCR6 RCR5 RCR4 RCR3 RCR2 RCR1 RCR0
MB86687A APPENDICESEdition 2.0
83
C. AC TIMINGS
Parameter Signal Abbrev Values Units
(ns)
g
Min Typical Max (ns)
Setup time of TDI TDI 1 ns
Hold time of TDI TDI 2 ns
TDO delay TDO 5 13 ns
TMS setup TMS 4 ns
TMS hold TMS 2 ns
Table 3 – JTAG Interface Timing
Fig. 60 – System Clock Timing
tDCKH tDCKL
tDCLK
DCCK
RESET
tRST
Fig. 61 – Reset Timing
Parameter Signal Abbrev Values Units
(ns)
g
Min Typical Max (ns)
Clock High Time DCCK tDCKH 13 ns
Clock Low Time DCCK tDCKL 15 ns
Clock Period DCCK tDCLK 30* ns
Reset Pulse Width RESET tRST 10 tDCLK ns
Table 4 – Miscellaneous – AC Timing Parameters
* Note: When the device is configured for Single cycle operation with 0 wait states
the clock period is restricted to 40ns
Note: On the following pages the following notation is used:
RMOD=0/1 means normal/extended read mode – CR15 RMOD bit
WMOD=0/1 means normal/extended write mode CR15 WMOD bit
ASYNC/SYNC means asynchronous/synchronous DMA interface CR15 SYN bit
Edition 2.0MB86687A APPENDICES
84
tTCKH
tTCKL
tTCLK
TXCLK
RXCLK
tRCKH
tRCKL
tRCLK
Fig. 62 – Cell Stream Clock Timing
Parameter Signal Abbrev Values Units
(ns)
g
Min Typical Max (ns)
Transmit Clock High Time TXCLK tTCKH 18 ns
Transmit Clock Low Time TXCLK tTCKL 18 ns
Transmit Clock Period TXCLK tTCLK 40* ns
Receive Clock High Time RXCLK tRCKH 16 ns
Receive Clock Low Time RXCLK tRCKL 17 ns
Receive Clock Period RXCLK tRCLK 40* ns
Table 5 – Cell Stream Interface clocks – AC Timing Parameters
* Note: In Fujitsu Cell Stream Mode the clock period is restricted to 50ns.
* Note: The period of TXCLK and RXCLK must be greater or equal to the period of
DCCK.
MB86687A APPENDICESEdition 2.0
85
TXCLK
TXD0–7 Output Data Byte 1 Output Data Byte 2
tOC
TXSOC
Output Data Byte 3
Fig. 63 – Cell Stream Interface Transmit Port (Fujitsu Mode) Timing
tOCI
Fig. 64 – Cell Stream Interface Receive Port (Fujitsu Mode) Timing
RXCLK
RXD0–7 Input Data Input Data
tDS tDH
RXSOC
RXEN
tOC tOC
Input Data Input Data
Parameter Signal Abbrev Values Units
(ns)
g
Min Typical Max (ns)
TXSOC, TXD Active Delay TXCLK tOC 10 20 ns
TXD Inactive Delay TXCLK tOCI 5ns
RXSOC, RXD Setup Time RXCLK tDS 0ns
RXSOC, RXD Hold Time RXCLK tDH 6ns
RXEN Delay RXCLK tOC 14 23 ns
Table 6 – Cell Stream Interface Fujitsu Mode – AC Timing Parameters
Edition 2.0MB86687A APPENDICES
86
Fig. 65 – Cell Stream Interface Transmit Port (Utopia mode) Timing
TXFULL
tDH
tOC
TXCLK
TXD0–7
TXSOC
TXEN
tDS
tOC tOCI
tOC
Fig. 66 – Cell Stream Interface Receive Port (Utopia mode) Timing
RXEMPTY
tDH
tOC
RXCLK
RXD0–7
tDS tDH
RXSOC
RXEN
tDS
tOC
Parameter Signal Abbrev Values Units
(ns)
g
Min Typical Max (ns)
TXSOC, TXD, TXEN Delay TXCLK tOC 822 ns
TXD Inactive Delay TXCLK tOC 5ns
TXFULL Setup Time TXCLK tDS 2ns
TXFULL Hold Time TXCLK tDH 2ns
RXSOC, RXD, RXEMPTY Setup RXCLK tDS 0ns
RXSOC, RXD, RXEMPTY Hold RXCLK tDH 6ns
RXEN Delay RXCLK tOC 15 28 ns
Table 7 – Cell Stream Interface UTOPIA Mode – AC Timing Parameters
MB86687A APPENDICESEdition 2.0
87
Fig. 67 – CSI Token Transmit and Receive Timing
tOC
ÌÌ
TOUT
Token Transmit
tDS tDH
TIN
TXCLK
Token Receive
tOC
Parameter Signal Abbrev Values Units
(ns)
g
Min Typical Max (ns)
TIN Setup Time TXCLK tDS 0ns
TIN Hold Time TXCLK tDH 5ns
TOUT Delay TXCLK tOC 11 20 ns
Table 8 – Cell Stream Interface Token Passing – AC Timing Parameters
Edition 2.0MB86687A APPENDICES
88
Ì
Ì
CS
RD
Valid Address
ÌÌ
ÌÌ
Fig. 68 – Microprocessor Interface – Read Timing
A1–A6
Valid Data
D0–D15
tAHR
tARD
tRDD tDRD
ÑÑÑ
ÑÑÑ
tRDCS
ÑÑÑ
tCSRD
ÌÌ
ÌÌ
CS
WR
Valid Address
A1–A6
Valid Data
D0–D15
tDH
tDS
tAWR
tWRW
tAHW
ÑÑÑ
ÑÑÑ
tWRCS
Fig. 69 – Microprocessor Interface – Write Timing
ÑÑÑ
tCSWR
MB86687A APPENDICESEdition 2.0
89
Parameter Signal Abbrev Values Units
(ns)
g
Min Typical Max (ns)
Address Valid to Read
Active RD tARD 0ns
CS Valid to Read Active RD tCSRD 0ns
Read Active to Valid Data RD tRDD 19 36 ns
Read Inactive to Invalid Data RD tDRD 5ns
Read Active to Invalid
Address RD tAHR 6ns
Read Inactive to CS
Inactive RD tRDCS 0ns
Address Active to Write
Active WR tAWR 0ns
CS Valid to Write Active WR tCSWR 0 ns
Write Pulse Width WR tWRW 5 ns
Data Setup Time WR tDS 5ns
Data Hold Time WR tDH 1ns
Write Active to Invalid
Address WR tAHW 6ns
Write Inactive to CS
Inactive WR tWRCS 0ns
Table 9 – Microprocessor Interface – AC Timing
Edition 2.0MB86687A APPENDICES
90
WR
tWWD
ÌÌ
Fig. 70 – Microprocessor Interface – Write to Write Timing
Fig. 71 – Microprocessor Interface – Interrupt Timing
DCCK
IRQ
RD
tIRQA tIRQI
WR
tWRIRQI
tIRQDEL
Parameter Signal Abbrev Values Units
(ns)
g
Min Typical Max (ns)
Write to Write Delay – DCCK WR tWWD 4DCCK ns
Write to Write Delay – TXCLK WR tWWT 4TXCLK* ns
IRQ Active Delay IRQ tIRQA 916 ns
WR Inactive to IRQ Inactive WR IRQ tWRIRQI 3DCCK 4DCCK ns
IRQ Inactive Delay IRQ tIRQI 40 ns
IRQ Inactive to Active IRQ tIRQDEL 2DCCK ns
Table 10 – Microprocessor Interface – AC Timing
*Note: See Fig. 30 – ALC Register Map, registers marked (T) denotes TXCLK write
recovery.
MB86687A APPENDICESEdition 2.0
91
Fig. 72 – Microprocessor Interface – Intel DMA Access Timing (SYNC)
HOLD
HLDA
A2–A23
BE0–3
RD & WR u processor u processor
DCLK
tHOLDA
tHLDAS
tADDRAZ tADDRIZ
tHOLDI
tHLDAH
BGACK
ALC bus valid
Fig. 73 – Microprocessor Interface – Intel DMA Access Timing (ASYNC)
HOLD
HLDA
A2–A23
BE0–3
RD & WR u processor u processor
DCLK
tHOLDA
tHLDAS
tADDRAZ tADDRIZ
tHOLDI
tHLDAH
BGACK
ALC bus valid
Edition 2.0MB86687A APPENDICES
92
Fig. 74 – Microprocessor Interface – Intel DMA Access Control Override Timing
ALC bus valid
tHLDAH
tHLDAS tHOLDI
tHOLDA
HOLD
HLDA
A2–A23
BE0–3
RD & WR u processor
DCLK
tHOLDA
tHLDAS
tADDRAZ
BGACK tADDRIZ
Parameter Signal Abbrev Values Units
(ns)
g
Min Typical Max (ns)
HOLD Active Delay HOLD tHOLDA 814 ns
HOLD Inactive Delay – ASYNC HOLD tHOLDI 75 ns
HOLD Inactive Delay –SYNC HOLD tHOLDI 10 22 ns
Setup Time of HLDA Active –
ASYNC HLDA tHLDAS 1 ns
Setup Time of HLDA Active –
SYNC HLDA tHLDAS 7 ns
Hold Time of HLDA Invalid –
ASYNC HLDA tHLDAH 1 ns
Hold Time of HLDA Invalid –
SYNC HLDA tHLDAH 2 ns
ALC Bus Active Delay A2–A23,
BE3–0,
MRD,
MWR,
tADDRAZ 516 ns
ALC Bus Inactive Delay A2–A23,
BE3–0,
MRD,
MWR
tADDRIZ 75 ns
Table 11 – Microprocessor Interface – Intel DMA Access AC Timing
MB86687A APPENDICESEdition 2.0
93
Fig. 75 – Microprocessor Interface – Motorola DMA Access Timing (SYNC)
DCLK
BR
BG
u processor
ALC bus valid
tBRA
tBGS
tADDRA
tBRI
A2–A23,
SIZ0–1,
DS, AS
& R/W
BGACK
tADDRIZ
tBGH
u processor
Fig. 76 – Microprocessor Interface – Motorola DMA Access Timing (ASYNC)
DCLK
BR
BG
u processor
ALC bus valid
tBRA
tBGS
tADDRA
tBRI
A2–A23,
SIZ0–1,
DS, AS
& R/W
BGACK
tADDRIZ
tBGH
u processor
Edition 2.0MB86687A APPENDICES
94
Parameter Signal Abbrev Values Units
(ns)
g
Min Typical Max (ns)
BR Active Delay BR tBRA 814 ns
BR Inactive Delay – ASYNC BR tBRI 75 ns
BR Inactive Delay – SYNC BR tBRI 10 22 ns
Setup Time of BG, AS & BGACK
Active – ASYNC BG tBGS 1ns
Setup Time of BG, AS & BGACK
Active – SYNC BG tBGS 8ns
Hold Time of BG, AS & BGACK
Invalid – ASYNC BG tBGH 1ns
Hold Time of BG, AS & BGACK
Invalid – SYNC BG tBGH 0ns
ALC Bus Active Delay A2–A23,
SIZ0–1,
DS, AS,
R/W
tADDRAZ 516 ns
ALC Bus Inactive Delay A2–A23,
SIZ0–1,
DS, AS,
R/W
tADDRIZ 75 ns
Table 12 – Microprocessor Interface – Motorola DMA Access AC Timing
MB86687A APPENDICESEdition 2.0
95
DCCK
RD
DATA
Fig. 77 – DPR / DMA Interface – Intel Read Cycle (SYNC)
A2–A23
BE0 BE1
BE2 BE3
READY
tADDRA tRDA
tRDYH
tRDYS
tDATS
tDATH
tRDI
tADDRI
tRDW
D0–D31
**CS
(TOCS etc)
tCSA tCSI
DCCK
RD
DATA
Fig. 78 – DPR / DMA Interface – Intel Read Cycle (ASYNC)
A2–A23
BE0 BE1
BE2 BE3
READY
tADDRA tRDA
tRDYS tRDYH
tDATS tDATH
tRDI
tADDRI
tRDW
D0–D31
**CS
(TOCS etc)
tCSA tCSI
Edition 2.0MB86687A APPENDICES
96
Fig. 79 – DPR / DMA Interface – Intel Write Cycle (SYNC)
DCCK
WR
DATA
A2–A23
BE0 BE1
BE2 BE3
READY
tADDRA
tWRA
tDATA
tWRW
tADDRI
tWRI
tDATI
tRDYH
tRDYS
D0–D31
Fig. 80 – DPR / DMA Interface – Intel Write Cycle (ASYNC)
DCCK
WR
DATA
A2–A23
BE0 BE1
BE2 BE3
READY
tADDRA
tWRA
tDATA
tWRW
tADDRI
tWRI
tDATI
tRDYH
tRDYS
D0–D31
MB86687A APPENDICESEdition 2.0
97
Parameter Signal Abbrev Values Units
(ns)
g
Min Typical Max (ns)
Address Active Delay A2–A23 tADDRA 15 28 ns
BE Active Delay – non burst BE0–BE3 tADDRA 13 22 ns
BE Active Delay – burst BE0–BE3 tADDRA 15 24 ns
Address BE Inactive Delay A2–A23 tADDRI 5ns
Read Active Delay RD tRDA 10 17 ns
Read Inactive Delay – RMOD=0 RD tRDI 916 ns
Read Inactive Delay – RMOD=1 RD tRDI 916 ns
Setup Time of Ready – ASYNC READY tRDYS 1ns
Setup Time of Ready – SYNC READY tRDYS 2ns
Hold Time of Ready – ASYNC READY tRDYH 2ns
Hold Time of Ready – SYNC READY tRDYH 1ns
Read Active Width (RMOD=0) RD tRDW tDCCK 1ns ns
Setup Time of Data – RMOD=0 D0–D31 tDATS 0 ns
Setup Time of Data – RMOD=1 D0–D31 tDATS 6 ns
Hold Time of Data – RMOD=0 D0–D31 tDATH 10 ns
Hold Time of Data – RMOD=1 D0–D31 tDATH 7 ns
Write Active Delay WR tWRA 10 17 ns
Write Inactive Delay –
WMOD=0 WR tWRI 916 ns
Write Inactive Delay –
WMOD=1 WR tWRI 916 ns
Write Active Width (WMOD=0) WR tWRW tDCCK 1ns ns
Write Data Active Delay D0–D31 tDATA 13 22 ns
Write Data Inactive delay D0–D31 tDATI 5 ns
Parity Active delay PRTY 0–3 15 24 ns
Cycle Start Active delay **CS tCSA 11 20 ns
Cycle State Inactive delay **CS tCSI 917 ns
Table 13 – DPR / DMA Interface – Intel Cycle AC Timing
Edition 2.0MB86687A APPENDICES
98
DCCK
AS
DATA
Fig. 81 – DPR / DMA Interface – Motorola Read Cycle (SYNC)
A0–A23
DTACK
DS
D0–D31
SIZ0, SIZ1
tADDRA tASDSA
tDTKS
tASDSI
tADDRI
tDATS tDATH
tDTKH
tASDSW
DCCK
AS
DATA
Fig. 82 – DPR / DMA Interface – Motorola Read Cycle (ASYNC)
A0–A23
DTACK
DS
D0–D31
SIZ0, SIZ1
tADDRA tASDSA
tDTKS
tASDSI
tADDRI
tDATS tDATH
tDTKH
tASDSW
MB86687A APPENDICESEdition 2.0
99
DCCK
R / W
DATA
A0–A23
SIZ0, SIZ1
DTACK
AS
DS
D0–D31
tADDRA
tASA
tDATA
tDSA
tDSW
tASW
tDTKS
tDTKH
tASDSI
tDATI
tADDRI
Fig. 83 – DPR / DMA Interface – Motorola Write Cycle (SYNC)
Fig. 84 – DPR / DMA Interface – Motorola Write Cycle (ASYNC)
DCCK
R / W
DATA
A0–A23
SIZ0, SIZ1
DTACK
AS
DS
D0–D31
tADDRA
tASA
tDATA
tDSA
tDSW
tASW
tDTKS tDTKH
tASDSI
tDATI
tADDRI
Edition 2.0MB86687A APPENDICES
100
Parameter Signal Abbrev Values Units
(ns)
g
Min Typical Max (ns)
Address Active delay A2–A23 tADDRA 15 28 ns
SIZ0/1 Active Delay – non burst SIZ0/1 tADDRA 13 22 ns
SIZ0/1 Active Delay – burst SIZ0/1 tADDRA 15 24 ns
Address SIZ0/1 Inactive Delay A2–A23 tADDRI 5ns
R/W Delay R/W 15 24 ns
Read AS Active Delay AS tASDSA 11 17 ns
Read DS Active Delay DS tASDSA 9 16 ns
Read AS Inactive Delay –
RMOD=0 AS tASDSI 10 17 ns
Read DS Inactive Delay –
RMOD=0 DS tASDSI 9 16 ns
Read AS Inactive Delay –
RMOD=1 AS 8 14 ns
Setup Time of DTACK –
ASYNC DTACK tDTKS 1 ns
Setup Time of DTACK – SYNC DTACK tDTKS 2 ns
Hold Time of DTACK – ASYNC DTACK tDTKH 2 ns
Hold Time of DTACK – SYNC DTACK tDTKH 1 ns
Read DS Active Width DS tDSW tDCCK 1ns ns
Setup Time of Data – RMOD=0 D0–D31 tDATS 0 ns
Setup Time of Data – RMOD=1 D0–D31 6 ns
Hold Time of Data – RMOD=0 D0–D31 tDATH 10 ns
Hold Time of Data – RMOD=1 D0–D31 7 ns
Write AS Active Delay AS tASA 11 17 ns
Write DS Active Delay DS tDSA 916 ns
Write AS Inactive Delay AS tASDSI 10 17 ns
Write DS Inactive Delay DS tASDSI 9 16 ns
Write AS Active Width AS tASW tDCCK 1ns ns
Write DS Active Width DS tDSW 1/2 tDCCK
1ns ns
Write Data Active Delay D0–D31 tDATA 13 22 ns
Write Data Inactive Delay D0–D31 tDATI 5 ns
Table 14 – DPR / DMA Interface – Motorola Cycle AC Timing
MB86687A APPENDICESEdition 2.0
101









Fig. 85 – Single Cycle Burst – Intel Extended Cycle (SBL=0, SYNC)
 
 

 
  
 
 


Fig. 86 – Single Cycle Burst – Intel Extended Cycle (SBL=0, ASYNC)









 
 



  
 
 


Edition 2.0MB86687A APPENDICES
102
Parameter Signal Abbrev Values Units
(ns)
g
Min Typical Max (ns)
Address Active Delay A23–2 tADDRA 15 28 ns
Write/Read Active Delay W/R tADDRA 16 26 ns
BE Active Delay BE3–0 tADDRA 15 24 ns
Address BE Write/Read Inactive
Delay A23–2,
BE3–0 W/R tADDRI 5ns
ADS Active Delay ADS tADSA 13 22 ns
ADS Inactive Delay ADS tADSI 11 19 ns
BLAST Active Delay BLAST tBLSTA 17 29 ns
BLAST Inactive Delay BLAST tBLSTI 7 14 ns
Setup Time of Data (Data Burst no
parity) SRD31–0 tDATS 0 ns
Hold Time of Data SRD31–0 tDATH 7 ns
Write Active Delay1 SRD31–0 tDATA1 13 22 ns
Write Active Delay2 SRD31–0 tDATA2 17 28 ns
Write Inactive Delay SRD31–0 tDATI 5 ns
Setup Time of SYNC READY READY tSRDYS 2ns
Hold T ime of SYNC READY READY tSRDYH 1ns
Setup T ime of ASYNC READY READY tARDYS 1ns
Hold T ime of ASYNC READY READY tARDYH 2ns
Table 15 – Single Cycle Burst – Intel Extended Cycle Timing
MB86687A APPENDICESEdition 2.0
103
Fig. 87 – Single Cycle Burst – Motorola Extended Cycle (SBL=0, SYNC)








 
 



  
 
 



Fig. 88 – Single Cycle Burst – Motorola Extended Cycle (SBL=0, ASYNC)








 
 

 
  
 
 



Edition 2.0MB86687A APPENDICES
104
Parameter Signal Abbrev Values Units
(ns)
g
Min Typical Max (ns)
Address Active Delay A23–2 tADDRA 15 28 ns
R/W Active Delay R/W tADDRA 15 24 ns
SIZ0, SIZ1 Active Delay SIZ0, SIZ1 tADDRA 15 24 ns
Address BE Write/Read Inactive
Delay A23–2,
SIZ0, SIZ1,
W/R
tADDRI 5ns
TS Active Delay TS tTSA 13 22 ns
TS Inactive Delay TS tTSI 11 19 ns
TIP Active Delay TIP tTIPA 12 20 ns
TIP Inactive Delay TIP tTIPI 10 18 ns
Setup Time of Data (Data Burst no
parity) SRD31–0 tDATS 0 ns
Hold Time of Data SRD31–0 tDATH 7 ns
Write Active Delay1 SRD31–0 tDATA1 13 22 ns
Write Active Delay2 SRD31–0 tDATA2 17 28 ns
Write Inactive Delay SRD31–0 tDATI 5 ns
Setup Time of SYNC DTACK DTACK tSDTKS 2 ns
Hold Time of SYNC DTACK DTACK tSDTKH 1 ns
Setup Time of ASYNC DTACK DTACK tADTKS 1 ns
Hold Time of ASYNC DTACK DTACK tADTKH 2 ns
Table 16 – Single Cycle Burst – Motorola Extended Cycle Timing
MB86687A APPENDICESEdition 2.0
105
D. RATINGS
D.1 Absolute Maximum
Ratings
Rating Symbol Values Units
g
y
Min Max
Positive Supply Voltage +VDD –0.5 6.0 V
Input Voltage VDIN –0.5 +VDD + 0.5 V
Output Voltage VO1 –0.5 +VDD + 0.5 V
Input Current IMAX –10.0 125 
Storage Temperature TSTG –40 125 oC
NOTE: Permanent device damage may occur if the above Absolute Maximum Ratings are exceeded. Functional operation
should be restricted to the conditions as detailed in the operational sections of this datasheet. Exposure to absolute maximum
rating conditions for extended periods may affect device reliability.
D.2 DC Characteristics
Parameter Symbol Pin Test Condition Value Unit
y
Min. Typ. Max.
Positive Supply Voltage VDD +4.75 +4.75 +5.0 +5.25 V
Positive Supply Current +IVS Static no load 100 mA
Input High Voltage (TTL) VIH 2.2 +VDD V
Input Low Voltage (TTL) VIL 0 0.8 V
Input Leakage Current IL0<=VI<=+VDD –10 10 A
Pull–up Input Leakage Current ILUL2 0<=VI<=+VDD –190 –38 A
Input Leakage Current ILZH1 0<=VI<=+VDD –10 10 A
Output Low Voltage VOL IOL=3.2mA VSS 0.4 V
Output High Voltage VOH IOH=–2mA 4.2 VDD V
Output Off Leakage Current ILO –10 10 mA
Input Pin Capacitance Cin 8 pF
Output Pin Capacitance Cout 16 pF
I/O Pin Capacitance Ci/o 21 pF
Loading capacitance Cl60 pF
Operating Temperature TA0 +70 oC
Power Dissipation (operating) PO1000 mW
Edition 2.0MB86687A APPENDICES
106
E. JTAG
E.1 JTAG Cells
The Boundary Scan Register (BSR) consists of 123 registers, which form a serial shift
register starting from pin 83, moving in a generally anti–clockwise direction around the
chip to finish at pin 24.
It should be noted that none of the internal D–types which form the BSR are reset, and
hence are initially undefined. A valid pattern needs to be shifted into the register prior
to any testing. However, while the JTAG TAP controller is reset, the I/O pins are
connected through to the system logic.
I / O Pin Type: I = Input
C = Clock input
O = Output
B = Bidirectional
T = Tristate
Iu = Input with pull-up resistor.
BSR Cell Type: BSI 1 allows capture of device input pin and control of logic
input pin.
BSI 3 allows capture of device input pin only.
BSO allows capture of logic output pin and control of device
output pin ( = BSI1 ).
BSOE allows control of tristate-able output pin
(preset–able).
BSDI allows control of bidirectional pin (= BSOE).
BSBI allows capture and control of bidirectional input and
output pin ( = BSI 1 + BSO ).
Control Group No.: Denotes a JTAG BSR cell which controls a (group of)
tristate-able output(s) or bidirectional pin(s).
Controlled Group No.: Denotes a JTAG BSR cell which connects to a tristate-able
output or bidirectional pin which is controlled by the JTAG
BSR cell numbered in the previous column.
MB86687A APPENDICESEdition 2.0
107
1 BSI1 Iu 83 TXDRV
2 BSOE 1
3 BSO 1 T 88 DS/BLAST/TIP
4 BSDI 2
5 & 6 BSBI 2 B 93 MRD / AS/ ASD
7 BSO 1 T 94 MWR / R/W R/W
8 BSOE 3
9 BSO 3 T 95 HOLD / BR
10 BSI1 I 98 HLDA / BG
11 BSDI 4
12 & 13 BSBI 4 B 99 BGACK
14 BSI1 I 100 DTACK / READY
15 BSI1 I 101 RESET
16 BSI1 I 102 CS
17 BSOE 5
18 BSO 5 T 103 IRQ
19 BSI1 I 104 RD
20 BSI1 I 105 WR
21 BSI1 I 106 A1
22 BSI1 I 108 A2
23 BSI1 I 109 A3
24 BSI1 I 110 A4
25 BSI1 I 111 A5
26 BSI1 I 112 A6
27 BSI1 I 113 TEST
28 BSDI 6
29 & 30 BSBI 6 B 115 DATA0
31 & 32 BSBI 6 B 116 DATA1
33 & 34 BSBI 6 B 117 DATA2
35 & 36 BSBI 6 B 118 DATA3
37 & 38 BSBI 6 B 121 DATA4
39 & 40 BSBI 6 B 122 DATA5
41 & 42 BSBI 6 B 123 DATA6
43 & 44 BSBI 6 B 125 DATA7
45 & 46 BSBI 6 B 126 DATA8
47 & 48 BSBI 6 B 127 DATA9
49 & 50 BSBI 6 B 128 DATA10
51 & 52 BSBI 6 B 133 DATA11
53 & 54 BSBI 6 B 134 DATA12
55 & 56 BSBI 6 B 135 DATA13
57 & 58 BSBI 6 B 136 DATA14
59 & 60 BSBI 6 B 138 DATA15
Edition 2.0MB86687A APPENDICES
108
61 BSI3 C 139 DCCK
62 BSO O 140 TOUT
63 BSI1 I 155 TIN
64 BSOE 7
65 BSDI 8
66 BSO 7 T 143 TXSOC
67 BSI3 C 144 TXCLK
68 BSO 7 T 145 TXD0
69 BSO 7 T 146 TXD1
70 BSO 7 T 148 TXD2
71 BSO 7 T 149 TXD3
72 BSO 7 T 150 TXD4
73 BSO 7 T 151 TXD5
74 BSO 7 T 152 TXD6
75 BSO 7 T 153 TXD7
76 BSO O 156 RXEN
77 BSI1 I 157 RXSOC
78 BSI3 C 158 RXCLK
79 BSI1 I 159 RXD0
80 BSI1 I 160 RXD1
81 BSI1 I 161 RXD2
82 BSI1 I 162 RXD3
83 BSI1 I 163 RXD4
84 BSI1 I 166 RXD5
85 BSI1 I 168 RXD6
86 BSI1 I 169 RXD7
87 BSI1 Iu 167 TXFULL
88 BSO 7 T 55 TXEN
89 BSI1 Iu 56 RXEMPTY
90 BSI1 Iu 57 CS / UT
91 BSO 1 T 89 BE0 / SRA0
92 BSO 1 T 90 BE1 / SRA1
93 BSO 1 T 91 BE2 / SIZ0
94 BSO 1 T 92 BE3 / SIZ1
95 BSO 1 T 87 SRA2
96 BSO 1 T 197 SRA3
97 BSO 1 T 199 SRA4
98 BSO 1 T 202 SRA5
99 BSO 1 T 203 SRA6
100 BSO 1 T 204 SRA7
MB86687A APPENDICESEdition 2.0
109
101 BSO 1 T 8 SRA8
102 BSO 1 T 9 SRA9
103 BSO 1 T 11 SRA10
104 BSO 1 T 12 SRA11
105 BSO 1 T 13 SRA12
106 BSO 1 T 37 SRA13
107 BSO 1 T 39 SRA14
108 BSO 1 T 40 SRA15
109 BSO 1 T 41 SRA16
110 BSO 1 T 59 SRA17
111 BSO 1 T 62 SRA18
112 BSO 1 T 63 SRA19
113 BSO 1 T 64 SRA20
114 BSO 1 T 66 SRA21
115 BSO 1 T 67 SRA22
116 BSO 1 T 68 SRA23
117 BSO O 44 TOCS
118 BSO O 45 TDCS
119 BSO O 46 ROCS
120 BSO O 47 RDCS
121 & 122 BSBI 8 B 29 PRTY0
123 & 124 BSBI 8 B 31 PRTY1
125 & 126 BSBI 8 B 32 PRTY2
127 & 128 BSBI 8 B 33 PRTY3
129 BSI1 Iu 35 SADRV
130 & 131 BSBI 8 B 170 SRD0
132 & 133 BSBI 8 B 172 SRD1
134 & 135 BSBI 8 B 173 SRD2
136 &137 BSBI 8 B 175 SRD3
138 & 139 BSBI 8 B 178 SRD4
140 & 141 BSBI 8 B 179 SRD5
142 & 143 BSBI 8 B 181 SRD6
144 & 145 BSBI 8 B 185 SRD7
146 & 147 BSBI 8 B 187 SRD8
148 & 149 BSBI 8 B 190 SRD9
150 & 151 BSBI 8 B 192 SRD10
Edition 2.0MB86687A APPENDICES
110
152 & 153 BSBI 8 B 193 SRD11
154 & 155 BSBI 8 B 195 SRD12
156 & 157 BSBI 8 B 196 SRD13
158 & 159 BSBI 8 B 205 SRD14
160 & 161 BSBI 8 B 206 SRD15
162 & 163 BSBI 8 B 207 SRD16
164 & 165 BSBI 8 B 208 SRD17
166 & 167 BSBI 8 B 1 SRD18
168 & 169 BSBI 8 B 2 SRD19
170 & 171 BSBI 8 B 4 SRD20
172 & 173 BSBI 8 B 5 SRD21
174 & 175 BSBI 8 B 6 SRD22
176 & 177 BSBI 8 B 7 SRD23
178 & 179 BSBI 8 B 14 SRD24
180 & 181 BSBI 8 B 16 SRD25
182 & 183 BSBI 8 B 17 SRD26
184 & 185 BSBI 8 B 18 SRD27
186 & 187 BSBI 8 B 20 SRD28
188 & 189 BSBI 8 B 21 SRD29
190 & 191 BSBI 8 B 22 SRD30
192 & 193 BSBI 8 B 24 SRD31
C 73 TCK
I 75 TMS
I 77 TDI
T 81 TDO
RXSOC
RXCLK
RXD0
RXD1
RXD2
VSS
RXD3
RXD4
RXD5
RXD6
RXD7
VDD
N/C
N/C
N/C
N/C
VSS
SRD0
SRD1
SRD2
SRD3
SRD4
SRD5
SRD6
SRD7
SRD8
SRD9
VSS
SRD10
SRD11
SRD12
SRD13
VDD
SRA3
SRA4
SRA5
SRA6
SRA7
VSS
SRD14
SRD15
SRD16
SRD17
RD
IRQ
CS
RESET
VSS
DTACK/READY/BERR
BGACK
HLDA/BG
HOLD/BR
MWR / R/W / R/W
VDD
MRD/AS/ADS/TS
BE3/SIZ1
BE2/SIZ0
BE1/SRA1
VSS
BE0/SRA0
DS/ TIP/ BLAST
SRA2
N/C
TXDRV
TDO
TDI
N/C
TMS
N/C
VSS
N/C
RESERVED
SRA23
SRA22
VDD
SRA21
SRA20
SRA19
SRA18
SRA17
VSS
SRD19
SRD20
SRD21
SRD22
SRD23
SRA8
SRA9
SRA10
SRA11
SRA12
SRD24
SRD25
SRD26
SRD27
VSS
SRD28
SRD29
SRD30
SRD31
PRTY0
PRTY1
TOCS
TDCS
ROCS
RDCS
N/C
N/C
SRA16
PRTY2
SADRV
N/C
VSS
SRA13
SRA14
SRA15
VDD
VDD
RXEN
TIN
TXD7
TXD6
TXD5
VSS
TXD4
TXD3
TXD2
TXD1
TXD0
VDD
TXCLK
TXSOC
TOUT
DCCK
VSS
DATA15
DATA14
DATA13
DATA12
DATA11
DATA10
DATA9
DATA8
DATA7
DATA6
VSS
DATA5
DATA4
DATA3
DATA2
VDD
DATA1
DATA0
TEST
A6
A5
A4
A3
A2
A1
WR
ALC
PRTY3
126 52
53
78
105130156
157
182
208
Fig. 89 – ALC Pin Assignment
104
VDD
N/C
VSS
VSS
N/C
N/C
N/C
N/C
N/C
N/C
VDD
N/C
N/C
N/C
VDD
TXFULL
N/C
N/C
N/C
N/C
N/C
N/C
VSS
VDD
VSS
N/C
N/C
N/C
N/C
N/C
N/C
TCK
N/C
N/C
SRD18
N/C
N/C
VSS
CS/UT
N/C
TXEN
N/C
RXEMPTY
N/C
N/C
N/C
(T OP VIEW)
MB86687A
MB86687A APPENDICESEdition 2.0
111
F. PIN DESCRIPTION
F.1 Physical Pin Diagram
Edition 2.0MB86687A APPENDICES
112
F.2 Pin Description Table
Pin No. Pin Name Type Function
1 SRD18 I/O SAR Memory data bus bit 18
2 SRD19 I/O SAR Memory data bus bit 19
ÍÍÍÍÍ
3
ÍÍÍÍÍÍÍÍ
VSS
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
4 SRD20 I/O SAR Memory data bus bit 20
5 SRD21 I/O SAR Memory data bus bit 21
6 SRD22 I/O SAR Memory data bus bit 22
7 SRD23 I/O SAR Memory data bus bit 23
8 SRA8 O (3-state) SAR Memory address bit 8
9 SRA9 O (3-state) SAR Memory address bit 9
ÍÍÍÍÍ
ÍÍÍÍÍ
10
ÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍ
VDD
ÍÍÍÍ
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
11 SRA10 O (3-state) SAR Memory address bit 10
12 SRA11 O (3-state) SAR Memory address bit 11
13 SRA12 O (3-state) SAR Memory address bit 12
14 SRD24 I/O SAR Memory data bus bit 24
ÍÍÍÍÍ
ÍÍÍÍÍ
15
ÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍ
VSS
ÍÍÍÍ
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
16 SRD25 I/O SAR Memory data bus bit 25
17 SRD26 I/O SAR Memory data bus bit 26
18 SRD27 I/O SAR Memory data bus bit 27
19 N/C Not Connected
20 SRD28 I/O SAR Memory data bus bit 28
21 SRD29 I/O SAR Memory data bus bit 29
22 SRD30 I/O SAR Memory data bus bit 30
23 N/C Not Connected
24 SRD31 I/O SAR Memory data bus bit 31
25 N/C Not Connected
ÍÍÍÍÍ
ÍÍÍÍÍ
26
ÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍ
VSS
ÍÍÍÍ
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍ
ÍÍÍÍÍ
27
ÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍ
VDD
ÍÍÍÍ
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
28 N/C Not Connected
29 PRTY0 I/O Parity for SRD7 – SRD0
30 N/C Not Connected
31 PRTY1 I/O Parity for SRD15 – SRD8
32 PRTY2 I/O Parity for SRD23 – SRD16
33 PRTY3 I/O Parity for SRD31 – SRD24
34 N/C Not Connected
35 SADRV I SAR Memory constant drive
36 N/C Not Connected
37 SRA13 O (3-state) SAR Memory address bit 13
ÍÍÍÍÍ
ÍÍÍÍÍ
38
ÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍ
VSS
ÍÍÍÍ
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
39 SRA14 O (3-state) SAR Memory address bit 14
40 SRA15 O (3-state) SAR Memory address bit 15
MB86687A APPENDICESEdition 2.0
113
Pin No. Pin Name Type Function
41 SRA16 O (3-state) SAR Memory address bit 16
42 N/C Not Connected
ÍÍÍÍÍ
ÍÍÍÍÍ
43
ÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍ
VDD
ÍÍÍÍ
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
44 TOCS O Transmit Overhead Start of Cycle
45 TDCS O Transmit Data Start of Cycle
46 ROCS O Receive Overhead Start of Cycle
47 RDCS O Receive Data Start of Cycle
48 N/C Not Connected
49 N/C Not Connected
ÍÍÍÍÍ
ÍÍÍÍÍ
50
ÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍ
VSS
ÍÍÍÍ
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
51 N/C Not Connected
52 N/C Not Connected
53 N/C Not Connected
54 N/C Not Connected
55 TXEN O (high–Z) UTOPIA Transmit Enable
56 RXEMPTY I UTOPIA Receive Empty
57 CS/UT I Fujitsu Cell Stream / UTOPIA Select
58 N/C Not Connected
59 SRA17 O (3-state) SAR Memory address bit 53
ÍÍÍÍÍ
ÍÍÍÍÍ
60
ÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍ
VSS
ÍÍÍÍ
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍ
ÍÍÍÍÍ
61
ÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍ
VDD
ÍÍÍÍ
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
62 SRA18 O (3-state) SAR Memory address bit 18
63 SRA19 O (3-state) SAR Memory address bit 19
64 SRA20 O (3-state) SAR Memory address bit 20
65 N/C Not Connected
66 SRA21 O (3-state) SAR Memory address bit 21
67 SRA22 O (3-state) SAR Memory address bit 22
68 SRA23 O (3-state) SAR Memory address bit 23
69 N/C Not Connected
70 N/C Reserved
71 N/C Not Connected
ÍÍÍÍÍ
ÍÍÍÍÍ
72
ÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍ
VSS
ÍÍÍÍ
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
73 TCK I JTAG Port Clock
74 N/C Not Connected
75 TMS I JTAG Test Mode Select
76 N/C Not Connected
77 TDI I JTAG Data Input
78 N/C Not Connected
ÍÍÍÍÍ
79
ÍÍÍÍÍÍÍÍ
VDD
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
80 N/C Not Connected
Edition 2.0MB86687A APPENDICES
114
Pin No. Pin Name Type Function
81 TDO O JTAG Data Output
82 N/C Not Connected
83 TXDRV I Cell Stream Constant Drive
84 N/C Not Connected
ÍÍÍÍÍ
ÍÍÍÍÍ
85
ÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍ
VSS
ÍÍÍÍ
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
86 N/C Not Connected
87 SRA2 O (high–Z) SAR Memory data bus bit 62
88 DS / BLAST / TIP O (3–state) Data Strobe / Burst Last / Transfer in Progress
89 BE0 O (3-state) SAR Memory BE0/SRA0
90 BE1 O (3-state) SAR Memory BE1/SRA1
91 BE2 O (3-state) SAR Memory BE2/SIZ0
92 BE3 O (3-state) SAR Memory BE3/SIZ1
93 MRD/AS/ ADS / TS I/O SAR Memory MRD/AS/ADS / TS
94 MWR/ R/W/ R/W O (3-state) SAR Memory MWR/R/W / R/W
95 HOLD/BR O (high-Z) SAR Memory HOLD/BR
ÍÍÍÍÍ
ÍÍÍÍÍ
96
ÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍ
VSS
ÍÍÍÍ
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍ
ÍÍÍÍÍ
97
ÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍ
VDD
ÍÍÍÍ
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
98 HLDA/BG I SAR Memory HLDA/BG
99 BGACK O (high-Z) SAR Memory BGACK
100 DTACK/READY/BERR I SAR Memory DTACK/READY or Bus Error
101 RESET I ALC Master Reset input
102 CS I p Chip Select
103 IRQ O (high-Z) Interrupt Request
104 RD I p Read
105 WR I p Write
106 A1 I Microprocessor Address bit 1
107 VSS
108 A2 I Microprocessor Address bit 2
109 A3 I Microprocessor Address bit 3
110 A4 I Microprocessor Address bit 4
111 A5 I Microprocessor Address bit 5
112 A6 I Microprocessor Address bit 6
113 TEST I Test Input – connect to Vss
114 VDD
115 DATA0 I/O Microprocessor Data Bus bit 0
116 DATA1 I/O Microprocessor Data Bus bit 1
117 DATA2 I/O Microprocessor Data Bus bit 2
118 DATA3 I/O Microprocessor Data Bus bit 3
ÍÍÍÍÍ
119
ÍÍÍÍÍÍÍÍ
VSS
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
120 N/C Not Connected
MB86687A APPENDICESEdition 2.0
115
Pin No. Pin Name Type Function
121 DATA4 I/O Microprocessor Data Bus bit 4
122 DATA5 I/O Microprocessor Data Bus bit 5
123 DATA6 I/O Microprocessor Data Bus bit 6
124 N/C Not Connected
125 DATA7 I/O Microprocessor Data Bus bit 7
126 DATA8 I/O Microprocessor Data Bus bit 8
127 DATA9 I/O Microprocessor Data Bus bit 9
128 DATA10 I/O Microprocessor Data Bus bit 10
129 N/C Not Connected
ÍÍÍÍÍ
ÍÍÍÍÍ
130
ÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍ
VSS
ÍÍÍÍ
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍ
ÍÍÍÍÍ
131
ÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍ
VDD
ÍÍÍÍ
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
132 N/C Not Connected
133 DATA11 I/O Microprocessor Data Bus bit 11
134 DATA12 I/O Microprocessor Data Bus bit 12
135 DATA13 I/O Microprocessor Data Bus bit 13
136 DATA14 I/O Microprocessor Data Bus bit 14
137 N/C Not Connected
138 DATA15 I/O Microprocessor Data Bus bit 15
139 DCCK I DMA Cycle Clock input
140 TOUT O Token Out output
141 N/C Not Connected
ÍÍÍÍÍ
ÍÍÍÍÍ
142
ÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍ
VSS
ÍÍÍÍ
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
143 TXSOC O (3-state) Cell Stream Interface Transmit Sync
144 TXCLK I Cell Stream Interface Transmit
145 TXD0 O (3-state) Cell Stream Interface Transmit data bit 0
146 TXD1 O (3-state) Cell Stream Interface Transmit data bit 1
147 VDD
148 TXD2 O (3-state) Cell Stream Interface Transmit data bit 2
149 TXD3 O (3-state) Cell Stream Interface Transmit data bit 3
150 TXD4 O (3-state) Cell Stream Interface Transmit data bit 4
151 TXD5 O (3-state) Cell Stream Interface Transmit data bit 5
152 TXD6 O (3-state) Cell Stream Interface Transmit data bit 6
153 TXD7 O (3-state) Cell Stream Interface Transmit data bit 7
ÍÍÍÍÍ
154
ÍÍÍÍÍÍÍÍ
VSS
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
155 TIN Token In input
156 RXEN O Indicates ALC receive buffers full
157 RXSOC I Cell Stream Interface Receive Sync
158 RXCLK I Cell Stream Interface Receive
159 RXD0 I Cell Stream Interface Receive data bit 0
160 RXD1 I Cell Stream Interface Receive data bit 1
Edition 2.0MB86687A APPENDICES
116
Pin No. Pin Name Type Function
161 RXD2 I Cell Stream Interface Receive data bit 2
162 RXD3 I Cell Stream Interface Receive data bit 3
163 RXD4 I Cell Stream Interface Receive data bit 4
ÍÍÍÍÍ
164
ÍÍÍÍÍÍÍÍ
VSS
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍ
ÍÍÍÍÍ
165
ÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍ
VDD
ÍÍÍÍ
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
166 RXD5 I Cell Stream Interface Receive data bit 5
167 TXFULL I UTOPIA Transmit Full
168 RXD6 I Cell Stream Interface Receive data bit 6
169 RXD7 I Cell Stream Interface Receive data bit 7
170 SRD0 I/O SAR Memory data bus bit 0
171 N/C Not Connected
172 SRD1 I/O SAR Memory data bus bit 1
173 SRD2 I/O SAR Memory data bus bit 2
174 N/C Not Connected
175 SRD3 I/O SAR Memory data bus bit 3
ÍÍÍÍÍ
ÍÍÍÍÍ
176
ÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍ
VSS
ÍÍÍÍ
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
177 N/C Not Connected
178 SRD4 I/O SAR Memory data bus bit 4
179 SRD5 I/O SAR Memory data bus bit 5
180 N/C Not Connected
181 SRD6 I/O SAR Memory data bus bit 6
182 N/C Not Connected
ÍÍÍÍÍ
ÍÍÍÍÍ
183
ÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍ
VDD
ÍÍÍÍ
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
184 N/C Not Connected
185 SRD7 I/O SAR Memory data bus bit 7
186 N/C Not Connected
187 SRD8 I/O SAR Memory data bus bit 8
188 N/C Not Connected
ÍÍÍÍÍ
189
ÍÍÍÍÍÍÍÍ
VSS
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
190 SRD9 I/O SAR Memory data bus bit 9
191 N/C Not Connected
192 SRD10 I/O SAR Memory data bus bit 10
193 SRD11 I/O SAR Memory data bus bit 11
194 N/C Not Connected
195 SRD12 I/O SAR Memory data bus bit 12
196 SRD13 I/O SAR Memory data bus bit 13
197 SRA3 O (3-state) SAR Memory address bit 3
198 N/C Not Connected
199 SRA4 O (3-state) SAR Memory address bit 4
ÍÍÍÍÍ
ÍÍÍÍÍ
200
ÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍ
VSS
ÍÍÍÍ
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍ
ÍÍÍÍÍ
201
ÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍ
VDD
ÍÍÍÍ
ÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
202 SRA5 O (3-state) SAR Memory address bit 5
203 SRA6 O (3-state) SAR Memory address bit 6
204 SRA7 O (3-state) SAR Memory address bit 7
205 SRD14 I/O SAR Memory data bus bit 14
206 SRD15 I/O SAR Memory data bus bit 15
207 SRD16 I/O SAR Memory data bus bit 16
208 SRD17 I/O SAR Memory data bus bit 17
MB86687A APPENDICESEdition 2.0
117
G. PACKAGE DIMENSIONS
.006 ± .002
.016 (0.40)
MAX
FPT-208P-M01
Dimensions in
inches (millimeters)
208-LEAD PLASTIC FLAT PACKAGE
(CASE No.: FPT-208P-M01)
1992 FUJITSU LIMITED F208001S–3C
1
156
157
208
52
53
104
105 0 (0) MIN
(STAND OFF HEIGHT)
Details of “A” part
.006 (0.15)
MAX
1.102 ±.004
(28.00 ±0.10)
LEAD No.
(MOUNTING HEIGHT)
.152 (3.85) MAX
(0.15 ± 0.05)
.020 ± .008
(0.50 ± 0.20)
1.205 ±.008
(30.60 ±0.20)
.0197 (0.50)
TYP
INDEX “A”
.008 (0.20)
.010 (0.25)
SQ
SQ
1.004
(25.50)
REF
Details of “B” part
.004 (0.10)
.003 (0.08)
“B”
1.165 (29.60)
NOM
.008 ± .004
(0.20 ± 0.10) M
0° to 10°
All Rights Reserved.
Circuit diagrams utilizing Fujitsu products are included as a means of illustrating typical applications.
Complete information sufficient for construction purposes is not necessarily given.
This information contained in this document does not convey any license under copyrights, patent
rights, software rights or trademarks claimed by Fujitsu.
The information contained in this document has been carefully checked and believed to be reliable.
However Fujitsu assumes no responsibility for inaccuracies.
Fujitsu reserves the right to change the product specifications without notice.
No part of this publication may be copied or reproduced in any form without the prior written consent
of Fujitsu.
Microelectronics
ATM–DS–20357–8/96
Worldwide Headquarters
Japan Fujitsu Limited
Tel: ++81 44 754 3753 1015 Kamiodanaka
Fax: ++81 44 754 3332 Nakahara–ku
Kawasaki 211
Japan
http://www.fujitsu.co.jp/
U.S.A
Tel: ++1 408 922 9000 Fujitsu Microelectronics Inc.
Fax: ++1 408 922 9179 3545 North First Street
San José CA 95134–1804
USA
Tel: ++1 800 866 8608 Customer Response Center
Fax: ++1 408 922 9179 Mon–Fri: 7am–5pm (PST)
http://www.fujitsumicro.com/
Asia Fujitsu Microelectronics Asia
PTE Limited
Tel: ++65–336 1600 No. 51 Bras Basah Road
Fax: ++65–336 1609 Plaza by the Park
#06–04/07
Singapore 0718
http://www.fsl.com.sg/
Europe
Tel: +49 (0) 6103 6900 Fujitsu Mikroelektronik GmbH
Fax:+49 (0) 6103 690122 Am Siebenstein 6–10
D–63303 Dreieich–Buchschlag
Germany
http://www.fujitsu.ede.com/