S1C62L81D - Seiko Epson Corporation

MF362-04

Technical Manual

CMOS 4-BIT SINGLE CHIP MICROCOMPUTER

S1C62N81 Technical Hardware/S1C62N81 Technical Software

S1C62N81

NOTICE

No part of this material may be reproduced or duplicated in any form or by any means without the written permission of Seiko

Epson. Seiko Epson reserves the right to make changes to this material without notice. Seiko Epson does not assume any

liability of any kind arising out of any inaccuracies contained in this material or due to its application or use in any product or

circuit and, further, there is no representation that this material is applicable to products requiring high level reliability, such

as medical products. Moreover, no license to any intellectual property rights is granted by implication or otherwise, and there

is no representation or warranty that anything made in accordance with this material will be free from any patent or copyright

infringement of a third party. This material or portions thereof may contain technology or the subject relating to strategic

products under the control of the Foreign Exchange and Foreign Trade Law of Japan and may require an export license from

the Ministry of International Trade and Industry or other approval from another government agency.

Royalty on Copyrighted Musical Pieces

When a musical selection under copyright is created in the melody ROM section of EPSON’s S1C62N81 and then marketed

in your country or any other country, permission to use the copyright is required in accordance with the Copyright Law.

For such purpose, in connection with the contract we have concluded with the Japan Music Copyright Association regarding

copyrights, customers using the S1C62N81 are required to apply with us before starting any software developments,

regardless of whether the melody ROM section will be used or not. We shall process the necessary copyrights based on said

application.

Due to the above-stated reasons, we shall bear no responsibility whatsoever in the following cases:

• When the musical selection applied with us differs from the actual musical selection used;

• When no application has been made with us in spite of the fact that musical selection has been incorporated in the ROM

section (this also applies to pirated musical pieces).

Moreover, please take note that there are exceptional cases in which processing anew of copyrights may be required in

accordance with the laws of the country of destination of the marketed product(s).

PREFACE

This manual is individualy described about the hardware and the software

of the S1C62N81.

I. S1C62N81 Technical Hardware

This part explains the function of the S1C62N81, the circuit configu-

rations, and details the controlling method.

II. S1C62N81 Technical Software

This part explains the programming method of the S1C62N81.

Hardware

Software

The information of the product number change

Configuration of product number

Devices

Comparison table between new and previous number

S1C60 Family processors

Starting April 1, 2001, the product number will be changed as listed below. To order from April 1,

2001 please use the new product number. For further information, please contact Epson sales

representative.

S1 C60N01 F0A01 Packing specification

Specification

Package (D: die form; F: QFP)

Model number

Model name (C: microcomputer, digital products)

Product classification (S1: semiconductor)

Development tools

S5U1 C60R08 D1 1Packing specification

Version (1: Version 1 ∗2)

Tool type (D1: Development Tool ∗1)

Corresponding model number (60R08: for S1C60R08)

Tool classification (C: microcomputer use)

Product classification

(S5U1: development tool for semiconductor products)

∗1: For details about tool types, see the tables below. (In some manuals, tool types are represented by one digit.)

∗2: Actual versions are not written in the manuals.

Previous No.

E0C6001

E0C6002

E0C6003

E0C6004

E0C6005

E0C6006

E0C6007

E0C6008

E0C6009

E0C6011

E0C6013

E0C6014

E0C60R08

New No.

S1C60N01

S1C60N02

S1C60N03

S1C60N04

S1C60N05

S1C60N06

S1C60N07

S1C60N08

S1C60N09

S1C60N11

S1C60N13

S1C60140

S1C60R08

S1C62 Family processors

Previous No.

E0C621A

E0C6215

E0C621C

E0C6S27

E0C6S37

E0C623A

E0C623E

E0C6S32

E0C6233

E0C6235

E0C623B

E0C6244

E0C624A

E0C6S46

New No.

S1C621A0

S1C62150

S1C621C0

S1C6S2N7

S1C6S3N7

S1C6N3A0

S1C6N3E0

S1C6S3N2

S1C62N33

S1C62N35

S1C6N3B0

S1C62440

S1C624A0

S1C6S460

Previous No.

E0C6247

E0C6248

E0C6S48

E0C624C

E0C6251

E0C6256

E0C6292

E0C6262

E0C6266

E0C6274

E0C6281

E0C6282

E0C62M2

E0C62T3

New No.

S1C62470

S1C62480

S1C6S480

S1C624C0

S1C62N51

S1C62560

S1C62920

S1C62N62

S1C62660

S1C62740

S1C62N81

S1C62N82

S1C62M20

S1C62T30

Comparison table between new and previous number of development tools

Development tools for the S1C60/62 Family

Previous No.

ASM62

DEV6001

DEV6002

DEV6003

DEV6004

DEV6005

DEV6006

DEV6007

DEV6008

DEV6009

DEV6011

DEV60R08

DEV621A

DEV621C

DEV623B

DEV6244

DEV624A

DEV624C

DEV6248

DEV6247

New No.

S5U1C62000A

S5U1C60N01D

S5U1C60N02D

S5U1C60N03D

S5U1C60N04D

S5U1C60N05D

S5U1C60N06D

S5U1C60N07D

S5U1C60N08D

S5U1C60N09D

S5U1C60N11D

S5U1C60R08D

S5U1C621A0D

S5U1C621C0D

S5U1C623B0D

S5U1C62440D

S5U1C624A0D

S5U1C624C0D

S5U1C62480D

S5U1C62470D

Previous No.

DEV6262

DEV6266

DEV6274

DEV6292

DEV62M2

DEV6233

DEV6235

DEV6251

DEV6256

DEV6281

DEV6282

DEV6S27

DEV6S32

DEV6S37

EVA6008

EVA6011

EVA621AR

EVA621C

EVA6237

EVA623A

New No.

S5U1C62620D

S5U1C62660D

S5U1C62740D

S5U1C62920D

S5U1C62M20D

S5U1C62N33D

S5U1C62N35D

S5U1C62N51D

S5U1C62560D

S5U1C62N81D

S5U1C62N82D

S5U1C6S2N7D

S5U1C6S3N2D

S5U1C6S3N7D

S5U1C60N08E

S5U1C60N11E

S5U1C621A0E2

S5U1C621C0E

S5U1C62N37E

S5U1C623A0E

Previous No.

EVA623B

EVA623E

EVA6247

EVA6248

EVA6251R

EVA6256

EVA6262

EVA6266

EVA6274

EVA6281

EVA6282

EVA62M1

EVA62T3

EVA6S27

EVA6S32R

ICE62R

KIT6003

KIT6004

KIT6007

New No.

S5U1C623B0E

S5U1C623E0E

S5U1C62470E

S5U1C62480E

S5U1C62N51E1

S5U1C62N56E

S5U1C62620E

S5U1C62660E

S5U1C62740E

S5U1C62N81E

S5U1C62N82E

S5U1C62M10E

S5U1C62T30E

S5U1C6S2N7E

S5U1C6S3N2E2

S5U1C62000H

S5U1C60N03K

S5U1C60N04K

S5U1C60N07K

Hardware

S1C62N81

Technical Har d ware

Hardware

S1C62N81 TECHNICAL HARDWARE EPSON I-i

CONTENTS

CHAPTER 1 INTRODUCTION............................................................... I-1

1.1 Configuration ................................................................... I-1

1.2 Features .......................................................................... I-2

1.3 Block Diagram ................................................................. I-3

1.4 Pin Layout Diagram......................................................... I-4

1.5 Pin Description ................................................................ I-5

CHAPTER 2 POWER SUPPLY AND INITIAL RESET ................................ I-6

2.1 Power Supply .................................................................. I-6

2.2 Initial Reset...................................................................... I-7

Oscillation detection circuit...................................... I-8

Reset pin (RESET) .................................................... I-8

Simultaneous high input to input ports (K00–K03) ... I-8

Internal register following initialization..................... I-9

2.3 Test Pin (TEST, MTEST) ................................................ I-9

CHAPTER 3 CPU, ROM, RAM ............................................................ I-10

3.1 CPU................................................................................ I-10

3.2 ROM ............................................................................... I-11

3.3 RAM ............................................................................... I-11

I-ii EPSON S1C62N81 TECHNICAL HARDWARE

CONTENTS

CHAPTER 4 PERIPHERAL CIRCUITS AND OPERATION ...................... I-12

4.1 Memory Map .................................................................. I-12

4.2 Oscillation Circuit............................................................ I-20

Crystal oscillation circuit......................................... I-20

CR oscillation circuit ............................................... I-21

4.3 Input Ports (K00–K03, K10) ........................................... I-22

Configuration of input ports .................................... I-22

Input comparison registers and interrupt function .. I-23

Mask option ............................................................ I-25

Control of input ports.............................................. I-26

4.4 Output Ports (R00–R03, R10–R12) ............................... I-29

Configuration of output ports .................................. I-29

Mask option ............................................................ I-30

Control of output ports............................................ I-32

4.5 I/O Ports (P00–P03) ....................................................... I-34

Configuration of I/O port ........................................ I-34

I/O control register and I/O mode........................... I-35

Mask option ............................................................ I-35

Control of I/O port .................................................. I-36

4.6 LCD Driver (COM0–COM3, SEG0–SEG25) .................. I-38

Configuration of LCD driver..................................... I-38

Switching between dynamic and static drive............ I-41

Mask option (segment allocation)............................. I-42

Control of LCD driver .............................................. I-44

4.7 Clock Timer .................................................................... I-45

Configuration of clock timer .................................... I-45

Interrupt function ................................................... I-46

Control of clock timer.............................................. I-47

Hardware

S1C62N81 TECHNICAL HARDWARE EPSON I-iii

CONTENTS

4.8 Stopwatch Timer ............................................................ I-50

Configuration of stopwatch timer ............................ I-50

Count-up pattern .................................................... I-51

Interrupt function ................................................... I-52

Control of stopwatch timer ...................................... I-53

4.9 Battery Voltage Low Detection (BLD) Circuit

and Heavy Load Protection Function ............................. I-56

Configuration of BLD circuit

and heavy load protection function.......................... I-56

Operation of BLD detection timing........................... I-58

Operation of heavy load protection function ............ I-59

Control of BLD circuit

and heavy load protection function.......................... I-60

4.10 Analog Voltage Comparator ........................................... I-62

Configuration of analog voltage comparator............. I-62

Operation of analog voltage comparator................... I-63

Control of analog voltage comparator ...................... I-64

4.11 Melody Generator........................................................... I-65

Outline of melody generator .................................... I-65

Melody data ............................................................ I-84

Playing of silent note ............................................... I-87

Envelope function ................................................... I-88

Playing tempo ......................................................... I-90

Playing mode........................................................... I-92

Control of the melody generator .............................. I-96

4.12 Interrupt and HALT........................................................ I-100

Interrupt factors..................................................... I-102

Specific masks and factor flags for interrupt........... I-103

Interrupt vectors and priorities............................... I-104

Control of interrupt ................................................ I-105

I-iv EPSON S1C62N81 TECHNICAL HARDWARE

CONTENTS

CHAPTER 5 BASIC EXTERNAL WIRING DIAGRAM........................... I-109

CHAPTER 6 ELECTRICAL CHARACTERISTICS ................................... I-112

6.1 Absolute Maximum Rating ............................................ I-112

6.2 Recommended Operating Conditions ........................... I-113

6.3 DC Characteristics ........................................................ I-114

6.4 Analog Circuit Characteristics

and Power Current Consumption .................................. I-116

6.5 Oscillation Characteristics ............................................. I-124

CHAPTER 7 PACKAGE ..................................................................... I-126

7.1 Plastic Package (1) ....................................................... I-126

7.2 Plastic Package (2) ....................................................... I-127

7.3 Ceramic Package for Test Sample................................ I-128

CHAPTER 8 PAD LAYOUT ................................................................. I-129

8.1 Diagram of Pad Layout.................................................. I-129

8.2 S1C62N81 List of Pad Names ...................................... I-130

8.3 Pad Coordinates............................................................ I-131

S1C62N81 TECHNICAL HARDWARE EPSON I-1

CHAPTER 1: INTRODUCTION

INTRODUCTION

Each member of the S1C62N81 Series of single chip micro-

computers feature a 4-bit S1C6200 core CPU, 1,024 words

of ROM (12 bits per word), 96 words of RAM (4 bits per

word), an LCD driver, 5 bits for input ports (K00–K03 and

K10), 7 bits for output ports (R00–R03 and R10–R12), one 4-

bit I/O port (P00–P03), two timer (clock timer and stopwatch

timer), and a melody generator.

Because of their low voltage operation and low power con-

sumption, the S1C62N81 Series are ideal for a wide range

of applications, and are especially suitable for battery-driven

systems with a melody.

CHAPTER 1

1.1

Table 1.1.1

Configuration of the

S1C62N81 Series

Configuration

The S1C62N81 Series are configured as follows, depending

on the supply voltage and oscillation circuits.

Model Supply Voltage Oscillation Circuits

S1C62N81 3.0 V Crystal

S1C62L81 1.5 V Crystal

S1C62A81 3.0 V CR

S1C62B81 1.5 V CR

I-2 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 1: INTRODUCTION

Features

Crystal or CR oscillation circuit, 32.768 kHz (typ.)

100 instructions

1,024 words ×12 bits

96 words × 4 bits

5 bits (Supplementary pull-down resistors may be used *1)

7 bits (*2), 1 bit melody output (Piezo buzzer can be driven

directry by mask option)

4 bits

26 segments × 4 common duty (or 3 common duty)

2 systems: clock timer/stopwatch timer

1 channel

Single-tone source generation, 15 tone intervals among 3

octaves, 8 notes, 2 tempos among 16 types

Optional number of melodies, within ROM capacity (80

words)

Supplementary envelope output may be used (*1)

Piezo buzzer can be driven directry (*1)

1.2 V / 2.4 V (*1)

Input port interrupt 2 systems

Timer interrupt 2 systems

Melody interrupt 1 system

1.5 V (0.9–3.5 V) S1C62L81, S1C62B81

3.0 V (1.8–3.5 V) S1C62N81, S1C62A81

1.0 µA (CLK = 32.768 kHz, when halted)

3.0 µA (CLK = 32.768 kHz, when executing)

64-pin QFP (plastic) or chip

1. May be selected with mask option

2. FOUT output is possible through mask option selections

1.2

Built-in oscillation circuit

Instruction set

ROM capacity

RAM capacity (data RAM)

Input port

Output port

Input/output port

LCD driver

Timer

Analog comparator

Melody generation circuit

Battery voltage low detec-

tion circuit (BLD)

Interrupts:External interrupt

Internal interrupt

Supply voltage

Current consumption (typ.)

Supply form

Note

S1C62N81 TECHNICAL HARDWARE EPSON I-3

CHAPTER 1: INTRODUCTION

1.3 Block Diagram

Fig. 1.3.1

Block diagram

Melody

Comparator

& BLD

Power

Controller

LCD

Driver

RAM

96x4 Interrupt

Generator

I Port

Test Port

I/O Port

O Port

Timer

Stop

Watch

Core CPU S1C6200

ROM

1,024x12 OSC System

Reset

Control

RESE

OSC1

COM0

COM3

SEG0

SEG25

K00–K03

K10

TEST

MTEST

P00–P03

R00–R03

R10, R11

OSC2

CMPP

CMPM

R12

I-4 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 1: INTRODUCTION

1.4

Index

116

48 33

Pin No

Pin Name

COM1

COM2

COM3

SEG25

SEG0

SEG1

SEG2

SEG3

SEG4

SEG5

SEG6

SEG7

SEG8

SEG9

SEG10

SEG11

Pin No

Pin Name

TEST

SEG12

SEG13

SEG14

SEG15

SEG16

SEG17

SEG18

SEG19

SEG20

SEG21

SEG22

SEG23

SEG24

N.C.

P00

Pin No

Pin Name

P01

P02

P03

CMPM

CMPP

MTEST

RESET

K00

K01

K02

K03

K10

R10

R11

R12

Pin No

Pin Name

R00

R01

R02

R03

OSC2

OSC1

COM0

(N.C. = No Connection)

Pin Layout Diagram

Fig. 1.4.1

Pin assignment

S1C62N81 TECHNICAL HARDWARE EPSON I-5

CHAPTER 1: INTRODUCTION

1.5

Table 1.5.1 Pin description

Terminal Name

CA–CC

OSC1

OSC2

K00–K10

P00–P03

R00–R03

R10

R11

R12

CMPP

CMPM

SEG0–25

COM0–3

RESET

TEST

MTEST

Pin No.

61, 62, 63

40–44

32–35

49–52

4–17

19–30

64, 1–3

Input/Output

(I)

–

I/O

Function

Power source (+) terminal

Power source (-) terminal

Oscillation and internal logic system regulated voltage output terminal

LCD system regulated voltage output terminal (approx. -1.05V)

LCD system booster output terminal (V 2)

LCD system booster output terminal (V 3)

Booster capacitor connecting terminal

Crystal or CR oscillation input terminal

Crystal or CR oscillation output terminal

Input terminal

I/O terminal

Output terminal

Output terminal (FOUT output available through mask option selection)

Ouput terminal

Output terminal (melody inverted output and

envelope function available through mask option selection)

Melody signal output terminal

Analog comparator non-inverted input terminal

Analog comparator inverted input terminal

LCD segment output terminal

(convertible to DC output terminal by mask option)

LCD common output terminal

Initial setting input terminal

Test input terminal

Melody test input terminal

Pin Description

I-6 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 2: POWER SUPPLY AND INITIAL RESET

POWER SUPPLY AND INITIAL

RESET

CHAPTER 2

2.1

Note

External

power

supply

Internal

circuit

Oscillation

circuit

LCD driver

circuit

LCD system

voltage

booster circuit

LCD system regulated

voltage circuit

Internal system

regulated voltage

circuit

VL1

VL2

VL3

Vss

VL1

VL2

VL3

VL1

OSC1, 2

COM0–3

SEG0–25

S1 S1

Power Supply

With a single external power supply (*1) supplied to VDD

through VSS, the S1C62N81 Series generate the necessary

internal voltages with the regulated voltage circuit (<VS1> for

oscillators and internal circuit, <VL1> for LCDs) and the

voltage booster circuit (<VL2, VL3> for LCDs).

Figure 2.1.1 shows the power supply configuration.

*1 Supply voltage: S1C62N81/62A81...3.0 V

S1C62L81/62B81...1.5 V

- External loads cannot be driven by the output voltage of the

regulated voltage circuit and voltage booster circuit.

- See Chapter 6, "ELECTRICAL CHARACTERISTICS", for

voltage values.

Fig. 2.1.1

Configuration of

power supply

S1C62N81 TECHNICAL HARDWARE EPSON I-7

CHAPTER 2: POWER SUPPLY AND INITIAL RESET

Initial Reset

To initialize the S1C62N81 Series circuits, an initial reset

must be executed. There are three ways of doing this.

(1)Initial reset by the oscillation detection circuit

(2)External initial reset via the RESET pin

(3)External initial reset by simultaneous high input to pins

K00–K03 (depending on mask option)

Figure 2.2.1 shows the configuration of the initial reset

circuit.

2.2

Vss

RESET

K03

K02

K01

K00

OSC2

OSC1

Oscillation

circuit

Vss

Oscillation

detection

circuit Noise

rejection

circuit

Initial

reset

Noise

rejection

circuit

Fig. 2.2.1

Configuration of

initial reset circuit

I-8 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 2: POWER SUPPLY AND INITIAL RESET

The oscillation detection circuit outputs the initial reset

signal at power-on until the crystal oscillation circuit starts

oscillating, or when the crystal oscillation circuit stops

oscillating for some reason.

An initial reset can be invoked externally by making the

reset pin high. This high level must be maintained for at

least 5 ms (when oscillating frequency, fosc = 32 kHz),

because the initial reset circuit contains a noise rejection

circuit. When the reset pin goes low the CPU begins to

operate.

Another way of invoking an initial reset externally is to input

a high signal simultaneously to the input ports (K00–K03)

selected with the mask option. The specified input port pins

must be kept high for 2–4 sec (when oscillating frequency

fosc = 32 kHz), because of the noise rejection circuit. Table

2.2.1 shows the combinations of input ports (K00–K03) that

can be selected with the mask option.

ANot used

BK00*K01

CK00*K01*K02

DK00*K01*K02*K03

When, for instance, mask option D (K00*K01*K02*K03) is

selected, an initial reset is executed when the signals input

to the four ports K00–K03 are all high at the same time.

If you use this function, make sure that the specified ports

do not go high at the same time during normal operation.

Oscillation detection

circuit

Reset pin (RESET)

Simultaneous high

input to input ports

(K00–K03)

Table 2.2.1

Input port combinations

S1C62N81 TECHNICAL HARDWARE EPSON I-9

CHAPTER 2: POWER SUPPLY AND INITIAL RESET

Internal register fol-

lowing initialization

2.3

An initial reset initializes the CPU as shown in the table

below.

Name

Program counter step

Program counter page

New page pointer

Stack pointer

Index register X

Index register Y

General register A

General register B

Interrupt flag

Decimal flag

Zero flag

Carry flag

Signal

PCS

PCP

NPP

Number of Bits

Setting Value

00H

Undefined

Peripheral Circuits

Name

RAM

Display memory

Other peripheral circuit

Number of Bits

96 × 4

26 × 4

–

Setting Value

Undefined

*1: See section 4.1, "Memory Map"

Test Pin (TEST, MTEST)

This pin is used when IC is inspected for shipment.

During normal operation connect it to VSS.

CPU Core

Table 2.2.2

Initial values

I-10 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 3: CPU, ROM, RAM

CPU, ROM, RAMCHAPTER 3

3.1 CPU

The S1C62N81 Series employs the S1C6200 core CPU, so

that register configuration, instructions, and so forth are

virtually identical to those in other processors in the family

using the S1C6200. Refer to the "S1C6200/6200A Core

CPU Manual" for details of the S1C6200.

Note the following points with regard to the S1C62N81

Series:

(1)The SLEEP operation is not provided, so the SLP instruc-

tion cannot be used.

(2)Because the ROM capacity is 1,024 words, 12 bits per

word, bank bits are unnecessary, and PCB and NBP are

not used.

(3)The RAM page is set to 0 only, so the page part (XP, YP) of

the index register that specifies addresses is invalid.

PUSH XP PUSH YP

POP XP POP YP

LD XP,r LD YP,r

LD r,XP LD r,YP

S1C62N81 TECHNICAL HARDWARE EPSON I-11

CHAPTER 3: CPU, ROM, RAM

ROM

The built-in ROM, a mask ROM for the program, has a

capacity of 1,024 × 12-bit steps. The program area is 4

pages (0–3), each consisting of 256 steps (00H–FFH). After

an initial reset, the program start address is page 1, step

00H. The interrupt vector is allocated to page l, steps 02H–

0BH.

Fig. 3.2.1

ROM configuration

3.2

3.3

00H step

02H step

0BH step

0CH step

FFH step

12 bits

Program start address

Interrupt vector area

Bank 0

Program area

0 page

1 page

2 page

3 page

01H step

RAM

The RAM, a data memory for storing a variety of data, has a

capacity of 96 words, 4-bit words. When programming,

keep the following points in mind:

(1)Part of the data memory is used as stack area when

saving subroutine return addresses and registers, so be

careful not to overlap the data area and stack area.

(2)Subroutine calls and interrupts take up three words on

the stack.

(3)Data memory 000H–00FH is the memory area pointed by

the register pointer (RP).

I-12 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Memory Map)

PERIPHERAL CIRCUITS AND OPERA-

TION

Peripheral circuits (timer, I/O, and so on) of the S1C62N81

Series are memory mapped. Thus, all the peripheral circuits

can be controlled by using memory operations to access the

I/O memory. The following sections describe how the pe-

ripheral circuits operate.

CHAPTER 4

4.1

Address

Page High

Low 0123456789ABCDEF

M0 M1 M2 M3 M4 M5 M6 M7 M8 M9 MA MB MC MD ME MF

RAM area (000H–05FH)

96 words x 4 bits (R/W)

I/O memory area Table 4.1.1 (a)–(g)

Display memory area (090H–0AFH)

32 words x 4 bits (Write only)

Unused area

Memory Map

The data memory of the S1C62N81 Series has an address

space of 154 words, of which 32 words are allocated to

display memory and 26 words, to I/O memory. Figure 4.1.1

show the overall memory mas for the S1C62N81 Series, and

Tables 4.1.1 (a)–(g), the memory maps for the peripheral

circuits (I/O space).

Fig. 4.1.1

Memory map

Memory is not mounted in unused area within the memory map

and in memory area not indicated in this chapter. For this reason,

normal operation cannot be assured for programs that have been

prepared with access to these areas.

Note

S1C62N81 TECHNICAL HARDWARE EPSON I-13

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Memory Map)

Table 4.1.1 (a) I/O memory map (0E0H–0E3H)

Address Comment

D3 D2 D1 D0 Name SR *1 10

0E0H

0E1H

0E2H

0E3H

K03 K02 K01 K00

0 0 0 K10

SWL3 SWL2 SWL1 SWL0

SWH3 SWH2 SWH1 SWH0

K03

K02

K01

K00

–

K10 –

Input port (K10)

SWL3

SWL2

SWL1

SWL0

SWH3

SWH2

SWH1

SWH0

MSB

Stopwatch timer

1/100 sec (BCD)

LSB

Input port (K00–K03)

High

Low

High Low

MSB

Stopwatch timer

1/10 sec (BCD)

LSB

* 1 Initial value following initial reset

* 2 Not set in the circuit

* 3 Undefined

* 4 Reset (0) immediately after being read

* 5 Constantly 0 when being read

* 6 Refer to main manual

I-14 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Memory Map)

Address Comment

D3 D2 D1 D0 Name SR *1 10

0E4H

0E5H

0E6H

0E7H

TM3 TM2 TM1 TM0

KCP03 KCP02 KCP01 KCP00

0 0 0 KCP10

0 0 0 EIMEL

R/W

TM3

TM2

TM1

TM0

–

KCP03

KCP02

KCP01

KCP00

Input comparison register (K03)

Input comparison register (K02)

Input comparison register (K01)

Input comparison register (K00)

KCP10 0

EIMEL 0 Enable Mask

Input comparison register (K10)

Timer data (clock timer 2 Hz)

Timer data (clock timer 4 Hz)

Timer data (clock timer 8 Hz)

Timer data (clock timer 16 Hz)

High

Low

Falling

Rising

Interrupt mask register (melody)

Falling Rising

R/W

Table 4.1.1 (b) I/O memory map (0E4H–0E7H)

* 1 Initial value following initial reset

* 2 Not set in the circuit

* 3 Undefined

* 4 Reset (0) immediately after being read

* 5 Constantly 0 when being read

* 6 Refer to main manual

S1C62N81 TECHNICAL HARDWARE EPSON I-15

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Memory Map)

Address Comment

D3 D2 D1 D0 Name SR *1 10

0E8H

0E9H

0EAH

0EBH

EIK03 EIK02 EIK01 EIK00

0 0 0 EIK10

0 0 EISW1 EISW0

0 EIT2 EIT8 EIT32

R/W

EIK03

EIK02

EIK01

EIK00

EIK10 0

Interrupt mask register (K10)

EISW1

EISW0

EIT2

EIT8

EIT32

Enable

Mask

Interrupt mask register (stopwatch 1 Hz)

Interrupt mask register (stopwatch 10 Hz)

Interrupt mask register (K03)

Interrupt mask register (K02)

Interrupt mask register (K01)

Interrupt mask register (K00)

Enable

Mask

Enable Mask

Interrupt mask register (clock timer 2 Hz)

Interrupt mask register (clock timer 8 Hz)

Interrupt mask register (clock timer 32 Hz)

Enable

Mask

R/W

Table 4.1.1 (c) I/O memory map (0E8H–0EBH)

* 1 Initial value following initial reset

* 2 Not set in the circuit

* 3 Undefined

* 4 Reset (0) immediately after being read

* 5 Constantly 0 when being read

* 6 Refer to main manual

I-16 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Memory Map)

Address Comment

D3 D2 D1 D0 Name SR *1 10

0ECH

0EDH

0EEH

0EFH

0 0 0 IMEL

00IK1IK0

0 0 ISW1 ISW0

0 IT2 IT8 IT32

IMEL 0

IK1

IK0

Interrupt factor flag (K10)

Interrupt factor flag (K00–K03)

ISW1

ISW0

IT2

IT8

IT32

Yes

Interrupt factor flag (stopwatch 1 Hz)

Interrupt factor flag (stopwatch 10 Hz)

Interrupt factor flag (melody)

Yes No

Yes

Interrupt factor flag (clock timer 2 Hz)

Interrupt factor flag (clock timer 8 Hz)

Interrupt factor flag (clock timer 32 Hz)

Yes

Table 4.1.1 (d) I/O memory map (0ECH–0EFH)

* 1 Initial value following initial reset

* 2 Not set in the circuit

* 3 Undefined

* 4 Reset (0) immediately after being read

* 5 Constantly 0 when being read

* 6 Refer to main manual

S1C62N81 TECHNICAL HARDWARE EPSON I-17

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Memory Map)

Address Comment

D3 D2 D1 D0 Name SR *1 10

0F0H

0F1H

0F2H

0F3H

MAD3 MAD2 MAD1 MAD0

0 MAD6 MAD5 MAD4

CLKC1 CLKC0 TEMPC MELC

R03 R02 R01 R00

R/W

MAD3

MAD2

MAD1

MAD0

MAD6

MAD5

MAD4

Melody ROM address (AD6, MSB)

Melody ROM address (AD5)

Melody ROM address (AD4)

CLKC1

CLKC0

TEMPC

MELC

R03

R02

R01

R00

High

Low

CLKC1(0)&CLKC0(0) : melody speed 1

CLKC1(0)&CLKC0(1) : melody speed 8

CLKC1(1)&CLKC0(0) : melody speed 16

CLKC1(1)&CLKC0(1) : melody speed 32

Tempo change control

Melody control ON/OFF

Melody ROM address (AD3)

Melody ROM address (AD2)

Melody ROM address (AD1)

Melody ROM address (AD0, LSB)

High

Low

High

Low

Output port data (R00–R03)

High

Low

OFF

R/W

Table 4.1.1 (e) I/O memory map (0F0H–0F3H)

* 1 Initial value following initial reset

* 2 Not set in the circuit

* 3 Undefined

* 4 Reset (0) immediately after being read

* 5 Constantly 0 when being read

* 6 Refer to main manual

I-18 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Memory Map)

Address Comment

D3 D2 D1 D0 Name SR *1 10

0F4H

0F6H

0F9H

0FAH

R12

ENV R11 R10

FOUT

P03 P02 P01 P00

0 TMRST SWRUN SWRST

HLMOD 0 BLDDT BLDON

R/W R12

ENV

R11

R10

FOUT

P03

P02

P01

P00

–

I/O port (P00–P03)

TMRST

SWRUN

SWRST

Reset

HLMOD

BLDDT

BLDON

0 ON OFF

Clock timer reset

Stopwatch timer RUN/STOP

Stopwatch timer reset

Output port data (R12)

Inverting melody output

Melody envelope control

Output port data (R11)

Output port data (R10)

Frequency output

High

–

High

Low

–

Low

OFF

High

Low

Heavy load protection mode register

Battery voltage detector data

Battery voltage detector ON/OFF

Reset

Run

Reset

–

Stop

–

R/W

R/W WR

R/W R/W

Heavy

load

Battery

voltage

low

Normal

load

Battery

voltage

normal

Table 4.1.1 (f) I/O memory map (0F4H, 0F6H, 0F9H–0FAH)

* 1 Initial value following initial reset

* 2 Not set in the circuit

* 3 Undefined

* 4 Reset (0) immediately after being read

* 5 Constantly 0 when being read

* 6 Refer to main manual

S1C62N81 TECHNICAL HARDWARE EPSON I-19

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Memory Map)

Address Comment

D3 D2 D1 D0 Name SR *1 10

0FBH

0FCH

CSDC 0 CMPDT CMPON

00 0IOC

IOC 0

I/O port P00–P03 Input/Output

LCD drive switch

Analog voltage comparator ON/OFF

Static

+ > -

Dynamic

- > +

Off

Output Input

R/W

R/W R/W

CSDC

CMPDT

CMPON

Comparator's voltage condition:

1 = CMPP(+)input > CMPM(-)input,

0 = CMPM(-)input > CMPP(+)input

Table 4.1.1 (g) I/O memory map (0FBH–0FCH)

* 1 Initial value following initial reset

* 2 Not set in the circuit

* 3 Undefined

* 4 Reset (0) immediately after being read

* 5 Constantly 0 when being read

* 6 Refer to main manual

I-20 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Oscillation Circuit)

Oscillation Circuit

The S1C62N81 Series have a built-in crystal oscillation

circuit. This circuit generates the operating clock for the

CPU and peripheral circuit on connection to an external

crystal oscillator (typ. 32.768 kHz) and trimmer capacitor

(5–25 pF).

Figure 4.2.1 is the block diagram of the crystal oscillation

circuit.

As Figure 4.2.1 indicates, the crystal oscillation circuit can

be configured simply by connecting the crystal oscillator

(X'tal) between the OSC1 and OSC2 pins and the trimmer

capacitor (CG) between the OSC1 and VDD pins.

4.2

Crystal oscillation

circuit

VDD CG

X'tal

OSC2

OSC1

CDVDD

To CPU and

peripheral circuits

The S1C62N81 Series

Fig. 4.2.1

Crystal oscillation circuit

S1C62N81 TECHNICAL HARDWARE EPSON I-21

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Oscillation Circuit)

For the S1C62N81 Series, CR oscillation circuit (typ. 32.768

kHz) may also be selected by a mask option. Figure 4.2.2 is

the block diagram of the CR oscillation circuit.

As Figure 4.2.2 indicates, the CR oscillation circuit can be

configured simply by connecting the register (R) between

pins OSC1 and OSC2 since capacity (C) is built-in.

See Chapter 6, "ELECTRICAL CHARACTERISTICS" for R

value.

CR oscillation circuit

OSC2

OSC1

To CPU and

peripheral circuits

The S1C62N81 Series

Fig. 4.2.2

CR oscillation circuit

I-22 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Input Ports)

Input Ports (K00–K03, K10)

The S1C62N81 Series have a general-purpose input (4 bits +

1 bit). Each of the input port pins (K00–K03, K10) has an

internal pull-down resistance. The pull-down resistance can

be selected for each bit with the mask option.

Figure 4.3.1 shows the configuration of input port.

Kxx

Vss

Mask option

Address

Interrupt

request

Data bus

Selecting "pull-down resistance enabled" with the mask

option allows input from a push button, key matrix, and so

forth. When "pull-down resistance disabled" is selected, the

port can be used for slide switch input and interfacing with

other LSIs.

4.3

Configuration of

input ports

Fig. 4.3.1

Configuration of input port

S1C62N81 TECHNICAL HARDWARE EPSON I-23

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Input Ports)

All five input port bits (K00–K03, K10) provide the interrupt

function. The conditions for issuing an interrupt can be set

by the software for the five bits. Also, whether to mask the

interrupt function can be selected individually for all five

bits by the software. Figure 4.3.2 shows the configuration of

K00–K03 and K10.

Input comparison

registers and inter-

rupt function

The input interrupt timing for K00–K03 and K10 depends on

the value set in the input comparison registers (KCP00–

KCP03 and KCP10). An interrupt can be set to occur on the

rising or falling edge of the input.

The interrupt mask registers (EIK00–EIK03, EIK10) enable

the interrupt mask to be selected individually for K00–K03

and K10. An interrupt occurs when the input value which

are not masked change so they no longer match those of the

input comparison register. An interrupt for K10 can be

generated by setting the same conditions individually.

When an interrupt is generated, the interrupt factor flag (IK0

and IK1) is set to 1.

Figure 4.3.3 shows an example of an interrupt for K00–K03.

Writing to the interrupt mask registers (EIK00–EIK03, EIK10)

should be done only in the DI status (interrupt flag = 0).

Otherwise, it causes malfunction.

Note

Data bus

Address

Interrupt mask

Input comparison

Kxx

Address

Mask option

(K00–K03, K10)

Noise

rejector

One for each pin series

Interrupt factor

flag (IK)

Interrupt

request

Address

Fig. 4.3.2

Input interrupt

circuit configuration

(K00–K03, K10)

I-24 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Input Ports)

Interrupt mask registers Input comparison registers

EIK03 EIK02 EIK01 EIK00 KCP03 KCP02 KCP01 KCP00

1110 1010

With the above setting, an interrupt for K00–K03 occurs under the

following conditions.

Input ports

(1) K03 K02 K01 K00

1010 (Initial value)

↓

(2) K03 K02 K01 K00

1011

↓

(3) K03 K02 K01 K00

0011

↓

(4) K03 K02 K01 K00

0111

↓

(5) K03 K02 K01 K00

1011

→Interrupt generated

K00 is masked, so the three bits of

K01–K03 cease to match those of the

input comparison register KCP01–

KCP03, and an interrupt occurs.

K00 is masked by the interrupt mask register (EIK00), so an

interrupt does not occur at (2). At (3), K03 changes to 0; the

data of the pin that is interrupt-enabled no longer matches

the data of the input comparison register, so an interrupt

occurs. As already explained, the condition for the interrupt

to occur is the change in the port data and contents of the

input comparison register so they no longer match. Hence,

in (4) or (5), when the nonmatching pattern changes to

another nonmatching pattern or matching pattern, an

interrupt does not occur. Also, pins that have been masked

for interrupt do not affect the conditions for interrupt gen-

eration.

Fig. 4.3.3

Example of interrupt

of K00–K03

S1C62N81 TECHNICAL HARDWARE EPSON I-25

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Input Ports)

The contents that can be selected with the input port mask

option are as follows:

(1) An internal pull-down resistance can be selected for each

of the five bits of the input ports (K00–K03, K10). Having

selected "pull-down resistance disabled", take care that

the input does not float. Select "pull-down resistance

enabled" for input ports that are not being used.

(2) The input interrupt circuit contains a noise rejection

circuit to prevent interrupts form occurring through

noise. The mask option enables selection of the noise

rejection circuit for each separate pin series. When "use"

is selected, a maximum delay of 0.5 ms (fosc = 32 kHz)

occurs from the time an interrupt condition is established

until the interrupt factor flag (IK) is set to 1.

Mask option

I-26 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Input Ports)

Tables 4.3.1 (a) and 4.3.1 (b) list the input port control bits

and their addresses.

Table 4.3.1 (a) Input port control bits (1)

Control of input ports

Address Comment

D3 D2 D1 D0 Name SR 1 0

0E0H

0E1H

K03 K02 K01 K00

0 0 0 K10

K03

K02

K01

K00

–

K10 –

Input port (K10)

Input port (K00–K03)

High

Low

High Low

0E5H

0E6H

KCP03 KCP02 KCP01 KCP00

0 0 0 KCP10

R/W

KCP03

KCP02

KCP01

KCP00

Input comparison register (K03)

Input comparison register (K02)

Input comparison register (K01)

Input comparison register (K00)

KCP10 0

Input comparison register (K10)

Falling

Rising

Falling Rising

R/W

S1C62N81 TECHNICAL HARDWARE EPSON I-27

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Input Ports)

Table 4.3.1 (b) Input port control bits (2)

Input port data (0E0H, 0E1H D0)

The input data of the input port pins can be read with these

registers.

When 1 is read: High level

When 0 is read: Low level

Writing: Invalid

The value read is 1 when the pin voltage of the five bits of

the input ports (K00–K03, K10) goes high (VDD), and 0 when

the voltage goes low (VSS). These bits are reading, so writing

cannot be done.

K00–K03, K10

Address Comment

D3 D2 D1 D0 Name SR 1 0

0E8H

0E9H

EIK03 EIK02 EIK01 EIK00

0 0 0 EIK10

R/W

EIK03

EIK02

EIK01

EIK00

EIK10 0

Interrupt mask register (K10)

Interrupt mask register (K03)

Interrupt mask register (K02)

Interrupt mask register (K01)

Interrupt mask register (K00)

Enable

Mask

Enable Mask

R/W

0EDH

00IK1IK0

IK1

IK0

Interrupt factor flag (K10)

Interrupt factor flag (K00–K03)

Yes

I-28 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Input Ports)

Input comparison registers (0E5H, 0E6H D0)

The interrupt conditions for pins K00–K03 and K10 can be

set with these registers.

When 1 is read: Falling edge

When 0 is read: Rising edge

Reading: Valid

Of the five bits of the input ports, the interrupt conditions

can be set for the rising or falling edge of the input for each

of the five bits (K00–K03 and K10) through the input com-

parison registers (KCP00–KCP03 and KCP10).

After an initial reset, these registers are set to 0.

Interrupt mask registers (0E8H, 0E9H D0)

Masking the interrupt of the input port pins can be done

with these registers.

When 1 is written: Enable

When 0 is written: Mask

Reading: Valid

With these registers, masking of the input port bits can be

done for each of the five bits. After an initial reset, these

registers are all set to 0.

Writing to these registers should be done only in the DI

status (interrupt flag = 0). Otherwise, it causes malfunction.

Interrupt factor flags (0EDH D0 and D1)

These flags indicate the occurrence of an input interrupt.

When 1 is read: Interrupt has occurred

When 0 is read: Interrupt has not occurred

Writing: Invalid

The interrupt factor flags IK0 and IK1 are associated with

K00–K03 and K10, respectively. From the status of these

flags, the software can decide whether an input interrupt

has occurred.

These flags are reset when the software has read them.

Reading should be done only in the DI status (interrupt flag

= 0). Otherwise, it causes malfunction.

After an initial reset, these flags are set to 0.

KCP00–KCP03, KCP10

EIK00–EIK03, EIK10

K0, IK1

S1C62N81 TECHNICAL HARDWARE EPSON I-29

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Output Ports)

Output Ports (R00–R03, R10–R12)

The S1C62N81 Series have 7 bits for general output ports

(R00–R03 and R10–R12).

Output specifications of the output ports can be selected

individually with the mask option. Two kinds of output

specifications are available: complementary output, and Pch

open drain output. Also, the mask option enables the

output ports R10 and R12 to be used as special output

ports. Figure 4.4.1 shows the configuration of the output

ports.

Configuration of

output ports

4.4

Data bus

Address

VDD

VSS

Rxx

Mask option

Complementary

Pch open drain

Fig. 4.4.1

Configuration of output ports

I-30 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Output Ports)

The mask option enables the following output port selection.

(1)Output specifications of output ports

The output specifications for the output ports (R00–R03,

R10–R12) may be either complementary output or Pch

open drain output for each of the seven bits. However,

even when Pch open drain output is selected, a voltage

exceeding the source voltage must not be applied to the

output port.

(2)Special output

In addition to the regular DC output, special output can

be selected for output ports R10 and R12, as shown in

Table 4.4.1. Figure 4.4.2 shows the structure of output

ports R10–R12.

Pin Name When Special Output is Selected

R12 MO or ENV

R10 FOUT

Mask option

Address

(0F4H)

FOUT

Data bus

R10

R11

R12

Mask option

(R12)

(R11)

(R10)

MO or

ENV

Table 4.4.1

Special output

Fig. 4.4.2

Structure of output port

R10–R12

S1C62N81 TECHNICAL HARDWARE EPSON I-31

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Output Ports)

When output port R10 is set for FOUT output, it outputs the

clock of fosc or the divided fosc. The clock frequency is

selectable by mask option from the frequencies listed in

Table 4.4.2.

Setting Value Clock Frequency (Hz)

fosc/1 32,768

fosc/2 16,384

fosc/4 8,192

fosc/8 4,096

fosc/16 2,048

fosc/32 1,024

fosc/64 512

fosc/128 256

(fosc = 32,768 Hz)

A hazard may occur when the FOUT signal is turned on or off.

R12 can select the following two functions using the mask

option as special output.

(1)Inverse output (MO) of melody output (MO)

Using the MO and MO terminals together, piezoelectric

buzzer may be driven directly. This means the minimum

number of external parts is necessary to play melodies.

(2)Envelope function

An envelope can be added when playing a melody by

connecting the play sound pressure damping capacitor to

terminal R12.

For details, see Chapter 5, "BASIC EXTERNAL WIRING

DIAGRAM", and Section 4.11, "Melody Generator".

FOUT (R10)

Note

MO, ENV (R12)

Table 4.4.2

FOUT clock frequency

I-32 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Output Ports)

Table 4.4.3 lists the output port control bits and their ad-

dresses.

Table 4.4.3 Control bits of output ports

Control of output

ports

Output port data (0F3H, 0F4H D0–D2)

Sets the output data for the output ports.

When 1 is written: High output

When 0 is written: Low output

Reading: Valid

The output port pins output the data written to the corre-

sponding registers (R00–R03, R10–R12) without changing it.

When 1 is written to the register, the output port pin goes

high (VDD), and when 0 is written, the output port pin goes

low (VSS). After an initial reset, all registers are set to 0.

R00–R03, R10–R12

(DC output)

Address Comment

D3 D2 D1 D0 Name SR 1 0

0F3H

R03 R02 R01 R00 R03

R02

R01

R00

High

Low

Output port data (R00–R03)

R/W

0F4H

R12

ENV

R11 R10

FOUT

R/W R12

ENV

R11

R10

FOUT

Output port data (R12)

Inverting melody output

Melody envelope control

Output port data (R11)

Output port data (R10)

Frequency output

High

–

High

Low

–

Low

OFF

S1C62N81 TECHNICAL HARDWARE EPSON I-33

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Output Ports)

Special output port data (0F4H D2)

This bit will not affect the melody (MO) or envelope (ENV)

signal at Rl2. R12 register is a general purpose register

which can be read and written.

When 1 is written: No effect at R12

When 0 is written: No effect at R12

Reading: Valid

Special output port data (0F4H D0)

Controls the FOUT (clock) output.

When 1 is written: Clock output

When 0 is written: Low level (DC) output

Reading: Valid

FOUT output can be controlled by writing data to R10. After

an initial reset, this register is set to 0.

Figure 4.4.3 shows the output waveform for FOUT output.

R12 (when MO or ENV is

selected)

R10 (when FOUT is

selected)

R10 Register

FOUT output

waveform

Fig. 4.4.3

FOUT output waveform

I-34 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (I/O Ports)

I/O Ports (P00–P03)

The S1C62N81 Series have a 4-bit general-purpose I/O port.

Figure 4.5.1 shows the configuration of the I/O port. The

four bits of the I/O port P00–P03 can be set to either input

mode or output mode. The mode can be set by writing data

to the I/O control register (IOC).

4.5

Configuration of I/O

port

Address

Input

control

I/O control

(IOC)

Data bus

Pxx

Fig. 4.5.1

Configuration of I/O port

S1C62N81 TECHNICAL HARDWARE EPSON I-35

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (I/O Ports)

Input or output mode can be set for the four bits of I/O port

P00–P03 by writing data into I/O control register IOC.

To set the input mode, 0 is written to the I/O control regis-

ter. When an I/O port is set to input mode, its impedance

becomes high and it works as an input port. However, the

input line is pulled down when input data is read.

The output mode is set when 1 is written to the I/O control

as an output port, it outputs a high signal (VDD) when the

port output data is 1, and a low signal (VSS) when the port

output data is 0.

After an initial reset, the I/O control register is set to 0, and

the I/O port enters the input mode.

The output specification during output mode (IOC = 1) of the

I/O port can be set with the mask option for either comple-

mentary output or Pch open drain output. This setting can

be performed for each bit of the I/O port. However, when

Pch open drain output has been selected, voltage in excess

of the supply voltage must not be applied to the port.

Mask option

I/O control register

and I/O mode

I-36 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (I/O Ports)

Table 4.5.1 lists the I/O port control bits and their ad-

dresses.

Control of I/O port

Table 4.5.1 I/O port control bits

Address Comment

D3 D2 D1 D0 Name SR 1 0

0F6H

P03 P02 P01 P00 P03

P02

P01

P00

–

I/O port (P00–P03)

High

Low

R/W

0FCH

0 0 0 IOC

IOC 0

I/O port P00–P03 Input/Output

Output Input

R/W

I/O port data (0F6H)

I/O port data can be read and output data can be written

through the port.

• When writing data

When 1 is written: High level

When 0 is written: Low level

When an I/O port is set to the output mode, the written

data is output from the I/O port pin unchanged. When 1

is written as the port data, the port pin goes high (VDD),

and when 0 is written, the level goes low (VSS). Port data

can also be written in the input mode.

• When reading data

When 1 is read: High level

When 0 is read: Low level

P00–P03

S1C62N81 TECHNICAL HARDWARE EPSON I-37

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (I/O Ports)

The pin voltage level of the I/O port is read. When the I/O

port is in the input mode the voltage level being input to

the port pin can be read; in the output mode the output

voltage level can be read. When the pin voltage is high

(VDD) the port data read is 1, and when the pin voltage is

low (VSS) the data is 0. Also, the built-in pull-down resis-

tance functions during reading, so the I/O port pin is

pulled down.

- When the I/O port is set to the output mode and a low-imped-

ance load is connected to the port pin, the data written to the

- When the I/O port is set to the input mode and a low-level

voltage (Vss) is input by the built-in pull-down resistance, an

erroneous input results if the time constant of the capacitive

load of the input line and the built- in pull-down resistance load

is greater than the read-out time. When the input data is being

read, the time that the input line is pulled down is equivalent to

0.5 cycles of the CPU system clock. Hence, the electric poten-

tial of the pins must settle within 0.5 cycles. If this condition

cannot be met, some measure must be devised, such as

arranging a pull-down resistance externally, or performing

multiple read-outs.

I/O control register (0FCH D0)

The input or output I/O port mode can be set with this

When 1 is written: Output mode

When 0 is written: Input mode

Reading: Valid

The input or output mode of the I/O port is set in units of

four bits. For instance, IOC sets the mode for P00–P03.

Writing 1 to the I/O control register makes the I/O port

enter the output mode, and writing 0, the input mode.

After an initial reset, the IOC register is set to 0, so the I/O

port is in the input mode.

Note

IOC

I-38 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (LCD Driver)

LCD Driver (COM0–COM3, SEG0–SEG25)

The S1C62N81 Series have four common pins and 26

(SEG0–SEG25) segment pins, so that an LCD with a maxi-

mum of 104 (26 × 4) segments can be driven. The power for

driving the LCD is generated by the CPU internal circuit, so

there is no need to supply power externally.

The driving method is 1/4 duty (or 1/3 duty by mask op-

tion) dynamic drive, adopting the four types of potential,

VDD, VL1, VL2 and VL3. The frame frequency is 32 Hz for 1/4

duty, and 42.7 Hz for 1/3 duty (in the case of fosc = 32.768

kHz). Figure 4.6.1 shows the drive waveform for 1/4 duty,

and Figure 4.6.2 shows the drive waveform for 1/3 duty.

fosc indicates the oscillation frequency of the oscillation circuit.

Configuration of LCD

driver

4.6

Note

S1C62N81 TECHNICAL HARDWARE EPSON I-39

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (LCD Driver)

LCD lighting status

COM0

COM1

COM2

COM3

Not lit

Lit

-V

COM0

COM1

COM2

COM3

SEG

0–25

Frame frequency

SEG0–25

Fig. 4.6.1

Drive waveform

for 1/4 duty

I-40 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (LCD Driver)

Frame frequency

SEG

0–25

COM3

COM2

COM1

COM0 -V

-V

Not lit

Lit

SEG0–25

LCD lighting status

COM0

COM1

COM2

Fig. 4.6.2

Drive waveform

for 1/3 duty

S1C62N81 TECHNICAL HARDWARE EPSON I-41

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (LCD Driver)

The S1C62N81 Series members allow software setting of the

LCD static drive. This function enables easy adjustment

(cadence adjustment) of the oscillation frequency of the OSC

circuit.

The procedure for executing of the LCD static drive is as

follows:

➀Write 1 to the CSDC register at address 0FBH D3.

➁Write the same value to all registers corresponding to

COM0–COM3 of the display memory.

- Even when l/3 duty is selected, the display data corresponding

to COM3 is valid for static drive. Hence, for static drive, set the

same value to all display memory corresponding COM0–COM3.

- For cadence adjustment, set the display data including display

data corresponding to COM3, so that all the LCD segments go

on.

Figure 4.6.3 shows the drive waveform for static drive.

Switching between

dynamic and static

drive

Note

SEG

0–25

COM

0–3

Frame frequency

LCD lighting status

COM0

COM1

COM2

COM3

SEG0–25

-V

Not lit Lit

-V

Fig. 4.6.3

LCD static drive waveform

I-42 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (LCD Driver)

(1)Segment allocation

As shown in Figure 4.l.1, the S1C62N81 Series display

data is decided by the display data written to the display

memory (write-only) at address 090H–0AFH.

The address and bits of the display memory can be made

to correspond to the segment pins (SEG0–SEG25) in any

combination through mask option. This simplifies design

by increasing the degree of freedom with which the liquid

crystal panel can be designed.

Figure 4.6.4 shows an example of the relationship be-

tween the LCD segments (on the panel) and the display

memory in the case of 1/3 duty.

Mask option

(segment allocation)

aa'

ff'

ee'

dd' p'

SEG10 SEG11 SEG12

Common 0

Common 1

Common 2

09AH

09BH

09CH

09DH

Address

Data

Display data memory allocation

SEG10

SEG11

SEG12

9A, D0

(a)

9A, D1

(b)

9D, D1

(f')

9B, D1

(f)

9B, D2

(g)

9A, D2

(c)

9B, D0

(e)

9A, D3

(d)

9B, D3

(p)

Pin address allocation

Common 0 Common 1 Common 2

Fig. 4.6.4

Segment allocation

S1C62N81 TECHNICAL HARDWARE EPSON I-43

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (LCD Driver)

(2)Drive duty

According to the mask option, either 1/4 or 1/3 duty can

be selected as the LCD drive duty.

Table 4.6.1 shows the differences in the number of seg-

ments according to the selected duty.

Pins Used Maximum Number Frame Frequency

in Common of Segments (when fosc = 32 kHz)

1/4 COM0–3 104 (26 × 4) 32 Hz

1/3 COM0–2 78 (26 × 3) 42.7 Hz

(3)Output specification

➀The segment pins (SEG0–SEG25) are selected by mask

option in pairs for either segment signal output or DC

output (VDD and VSS binary output). When DC output

is selected, the data corresponding to COM0 of each

segment pin is output.

➁When DC output is selected, either complementary

output or Pch open drain output can be selected for

each pin by mask option.

The pin pairs are the combination of SEG (2

n) and SEG (2

n +

1) (where n is an integer from 0 to 12).

Table 4.6.1

Differences according to

selected duty

Note

Duty

I-44 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (LCD Driver)

Table 4.6.2 shows the control bits of the LCD driver and

their addresses. Figure 4.6.5 shows the display memory

map.

Table 4.6.2 Control bits of LCD driver

LCD drive switch (0FBH D3)

The LCD drive format can be selected with this switch.

When 1 is written: Static drive

When 0 is written: Dynamic drive

Reading: Valid

After an initial reset, dynamic drive (CSDC = 0) is selected.

(090H–0AFH)

The LCD segments are turned on or off according to this

data.

When 1 is written: On

When 0 is written: Off

Reading: Invalid

By writing data into the display memory allocated to the

LCD segment (on the panel), the segment can be turned on

or off. After an initial reset, the contents of the display

memory are undefined.

Control of LCD

driver

CSDC

Display memory

Address Comment

D3 D2 D1 D0 Name SR 1 0

0FBH

CSDC 0 CMPDT CMPON

LCD drive switch

Voltage comparator ON/OFF

Static

+ > -

Dynamic

- > +

Off

R/W R/W

CSDC

CMPDT

CMPON

Comparator's voltage condition:

1 = CMPP(+)input > CMPM(-)input,

0 = CMPM(-)input > CMPP(+)input

Address 0123456789ABCDEF

090

0A0 Display memory (Write only)

32 words x 4 bits

Fig. 4.6.5

Display

memory map

S1C62N81 TECHNICAL HARDWARE EPSON I-45

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Clock Timer)

Clock Timer

The S1C62N81 Series have a built-in clock timer driven by

the source oscillator. The clock timer is configured as a

seven-bit binary counter that serves as a frequency divider

taking a 256 Hz source clock from a prescaler. The four

high-order bits (16 Hz–2 Hz) can be read by the software.

Figure 4.7.1 is the block diagram of the clock timer.

Normally, this clock timer is used for all kinds of timing

purpose, such as clocks.

4.7

Configuration of

clock timer

128 Hz–32 Hz

Data bus

32 Hz, 8 Hz, 2 Hz

256 Hz

Clock timer reset signal

OSC

(oscillation

circuit)

Interrupt

request

Interrupt

control

16 Hz–2 Hz

Fig. 4.7.1

Block diagram of

clock timer

I-46 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Clock Timer)

Fig. 4.7.2 Timing chart of the clock timer

The clock timer can interrupt on the falling edge of the 32

Hz, 8 Hz, and 2 Hz signals. The software can mask any of

these interrupt signals.

Figure 4.7.2 is the timing chart of the clock timer.

Interrupt function

As shown in Figure 4.7.2, an interrupt is generated on the

falling edge of the 32 Hz, 8 Hz, and 2 Hz frequencies. When

this happens, the corresponding interrupt event flag (IT32,

IT8, IT2) is set to 1. Masking the separate interrupts can be

done with the interrupt mask register (EIT32, EIT8, EIT2).

However, regardless of the interrupt mask register setting,

the interrupt event flags will be set to 1 on the falling edge of

their corresponding signal (e.g. the falling edge of the 2 Hz

signal sets the 2 Hz interrupt factor flag to 1).

Write to the interrupt mask register (EIT32, EIT8, EIT2) and read

the interrupt factor flags (IT32, IT8, IT2) only in the DI status

(interrupt flag = 0). Otherwise, it causes malfunction.

Note

Clock timer timing chart

Frequency

bits

Address

0E4H

D0 16 Hz

8 Hz

4 Hz

2 Hz

Occurrence of

32 Hz interrupt request

Occurrence of

8 Hz interrupt request

Occurrence of

2 Hz interrupt request

S1C62N81 TECHNICAL HARDWARE EPSON I-47

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Clock Timer)

Table 4.7.1 shows the clock timer control bits and their

addresses.

Control of clock

timer

Table 4.7.1 Control bits of clock timer

Address Comment

D3 D2 D1 D0 Name SR 1 0

0E4H

TM3 TM2 TM1 TM0

TM3

TM2

TM1

TM0

–

Timer data (clock timer 2 Hz)

Timer data (clock timer 4 Hz)

Timer data (clock timer 8 Hz)

Timer data (clock timer 16 Hz)

High

Low

0EBH

0 EIT2 EIT8 EIT32

EIT2

EIT8

EIT32

Enable

Mask

Interrupt mask register (clock timer 2 Hz)

Interrupt mask register (clock timer 8 Hz)

Interrupt mask register (clock timer 32 Hz)

R/W

0EFH

0 IT2 IT8 IT32 0

IT2

IT8

IT32

Yes

Interrupt factor flag (clock timer 2 Hz)

Interrupt factor flag (clock timer 8 Hz)

Interrupt factor flag (clock timer 32 Hz)

0F9H

0 TMRST SWRUN SWRST

TMRST

SWRUN

SWRST

Reset

Clock timer reset

Stopwatch timer RUN/STOP

Stopwatch timer reset

Reset

Run

Reset

–

Stop

–

R/W WR

I-48 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Clock Timer)

Timer data (0E4H)

The 16 Hz to 2 Hz timer data of the clock timer can be read

from this register. These four bits are read-only, and write

operations are invalid.

After an initial reset, the timer data is initialized to 0H.

Interrupt mask registers (0EBH D0–D2)

These registers are used to mask the clock timer interrupt.

When 1 is written: Enabled

When 0 is written: Masked

Reading: Valid

The interrupt mask register bits (EIT32, EIT8, EIT2) mask

the corresponding interrupt frequencies (32 Hz, 8 Hz, 2 Hz).

Writing to the interrupt mask registers should be done only

in the DI status. Otherwise, it causes malfunction.

After an initial reset, these registers are all set to 0.

Interrupt factor flags (0EFH D0–D2)

These flags indicate the status of the clock timer interrupt.

When 1 is read: Interrupt has occurred

When 0 is read: Interrupt has not occurred

Writing: Invalid

The interrupt factor flags (IT32, IT8, IT2) correspond to the

clock timer interrupts (32 Hz, 8 Hz, 2 Hz). The software can

determine from these flags whether there is a clock timer

interrupt. However, even if the interrupt is masked, the

flags are set to 1 on the falling edge of the signal. These

flags can be reset when the register is read by the software.

Also, the flags should be read only in the DI status (inter-

rupt flag = 0). Otherwise, it causes malfunction.

After an initial reset, these flags are set to 0.

EIT32, EIT8, EIT2

TM0–TM3

IT32, IT8, IT2

S1C62N81 TECHNICAL HARDWARE EPSON I-49

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Clock Timer)

Clock timer reset (0F9H D2)

This bit resets the clock timer.

When 1 is written: Clock timer reset

When 0 is written: No operation

Reading: Always 0

The clock timer is reset by writing 1 to TMRST. The clock

timer starts immediately after this. No operation results

when 0 is written to TMRST.

This bit is write-only, and so is always 0 when read.

TMRST

I-50 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Stopwatch Timer)

Stopwatch Timer

The S1C62N81 Series incorporate a 1/100 sec and 1/10 sec

stopwatch timer. The stopwatch timer is configured as a

two-stage, four-bit BCD timer serving as the clock source for

an approximately 100 Hz signal (obtained by approximately

dividing the 256 Hz signal output from the prescaler). Data

can be read out four bits at a time by the software.

Figure 4.8.1 is the block diagram of the stopwatch timer.

Configuration of

stopwatch timer

4.8

The stopwatch timer can be used separately from the clock

timer. In particular, digital stopwatch functions can be

easily realized by software.

SWL timer

Data bus

10 Hz, 1 Hz

256 Hz

Stopwatch timer reset signal

Stopwatch timer RUN/STOP signal

OSC

(oscillation

circuit)

Interrupt

request

Interrupt

control

10 Hz SWH timer

Fig. 4.8.1

Block diagram of

stopwatch timer

S1C62N81 TECHNICAL HARDWARE EPSON I-51

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Stopwatch Timer)

The stopwatch timer is configured as two four-bit BCD

timers, SWL and SWH. The SWL timer, at the stage preced-

ing the stopwatch timer, has an approximate l00 Hz signal

as its input clock. It counts up every 1/100 sec and gener-

ates an approximate 10 Hz signal. The SWH timer has an

approximate 10 Hz signal generated by the SWL timer for its

input clock. It counts up every 1/10 sec and generates a 1

Hz signal.

Figure 4.8.2 shows the count-up pattern of the stopwatch

timer.

SWL generates an approximate 10 Hz signal from the 256

Hz based signal. The count-up intervals are 2/256 sec and

3/256 sec, so that two final patterns are generated: a 25/

256 sec interval and a 26/256 sec interval. Consequently,

the count-up intervals are 2/256 sec and 3/256 sec, which

do not amount to an accurate 1/100 sec. SWH counts the

approximate 10 Hz signals generated by the 25/256 sec,

and 26/256 sec intervals in the ratio of 4:6 to generate a l

Hz signal. The count-up intervals are 25/256 sec and 26/

256 sec, which do not amount to an accurate 1/10 sec.

Count-up pattern

256 26

256

256 25

256

256 2

256 3

256 2

256

256 3

256

256 2

256

256 2

256

256 3

256

256 2

256

256 25

256

x 6 + x 4 = 1 (S)

0 1 2 3 4 5 6 7 8 9 0

1 Hz

signal

generation

Approximate

10 Hz

signal

generation

Approximate

10 Hz

signal

generation

SWH count value

Counting time (S)

(S)

SWL count value

Counting time (S)

SWL count value

Counting time (S)

SWH count-up pattern

SWL count-up pattern 1

SWL count-up pattern 2

Fig. 4.8.2

Count-up pattern of

stopwatch timer

I-52 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Stopwatch Timer)

The 10 Hz (approximate 10 Hz) and 1 Hz interrupts can be

generated by the overflow of the SWL and SWH stopwatch

timers, respectively. Also, software can separately mask the

frequencies as described earlier.

Figure 4.8.3 is the timing chart for the stopwatch timer.

As shown in Figure 4.8.3, the interrupts are generated by

the overflow of the respective timers (9 changing to 0). Also

when this happens, the corresponding interrupt factor flags

(ISW0, ISW1) are set to 1. The respective interrupts can be

masked separately with the interrupt mask registers

(EISW0, EISW1). However, regardless of the setting of the

interrupt mask registers, the interrupt factor flags are set to

1 by the overflow of the corresponding timers.

Write to the interrupt mask registers (EISW0, EISW1) and read the

interrupt factor flags (ISW0, ISW1) only in the DI status (interrupt

flag = 0). Otherwise, it causes malfunction.

Interrupt function

Note

Address

Stopwatch timer (SWH) timing chart

Occurrence of

10 Hz interrupt request

Occurrence of

1 Hz interrupt request

0E3H

(1/10 sec BCD)

0E2H

(1/100 sec BCD)

Fig. 4.8.3

Timing chart for

stopwatch timer

S1C62N81 TECHNICAL HARDWARE EPSON I-53

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Stopwatch Timer)

Table 4.8.1 shows the stopwatch timer control bits and their

addresses.

Table 4.8.1 Stopwatch timer control bits

Control of stopwatch

timer

Address Comment

D3 D2 D1 D0 Name SR 1 0

0E2H

0E3H

SWL3 SWL2 SWL1 SWL0

SWH3 SWH2 SWH1 SWH0

SWL3

SWL2

SWL1

SWL0

SWH3

SWH2

SWH1

SWH0

MSB

Stopwatch timer

1/100 sec (BCD)

LSB

MSB

Stopwatch timer

1/10 sec (BCD)

LSB

0EAH

0 0 EISW1 EISW0

EISW1

EISW0

Interrupt mask register (stopwatch 1 Hz)

Interrupt mask register (stopwatch 10 Hz)

Enable

Mask

R/W

0EEH

0 0 ISW1 ISW0

ISW1

ISW0

Interrupt factor flag (stopwatch 1 Hz)

Interrupt factor flag (stopwatch 10 Hz)

Yes

0F9H

0 TMRST SWRUN SWRST

TMRST

SWRUN

SWRST

Reset

Clock timer reset

Stopwatch timer RUN/STOP

Stopwatch timer reset

Reset

Run

Reset

–

Stop

–

R/W WR

I-54 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Stopwatch Timer)

1/100 sec stopwatch timer (0E2H)

Data (BCD) of the 1/100 sec column of the stopwatch timer

can be read. These four bits are read-only, and cannot be

written to.

After an initial reset, the timer data is set to 0H.

1/10 sec stopwatch timer (0E3H)

Data (BCD) of the 1/10 sec column of the stopwatch timer

can be read. These four bits are read-only, and cannot be

written to.

After an initial reset, the timer data is set to 0H.

Interrupt mask register (0EAH D0 and D1)

These registers mask the stopwatch timer interrupt.

When 1 is written: Enabled

When 0 is written: Masked

Reading: Valid

The interrupt mask register bits (EISW0, EISW1) are used to

mask the 10 Hz and 1Hz interrupts, respectively. Writing to

the interrupt mask registers should be done only in the DI

status (interrupt flag = 0). Otherwise, it causes malfunction.

After an initial reset, these registers are both set to 0.

Interrupt factor flags (0EEH D0 and D1)

These flags indicate the status of the stopwatch timer inter-

rupt.

When 1 is read: Interrupt has occurred

When 0 is read: Interrupt has not occurred

Writing: Invalid

The interrupt factor flags (ISW0, ISW1) correspond to the 10

Hz and 1 Hz interrupts, respectively. With these flags, the

software can determine whether a stopwatch timer interrupt

has occurred. However, regardless of the interrupt mask

flow. They are reset when the register is read by the soft-

ware. Also, reading should be done only in the DI status

(interrupt flag = 0). Otherwise, it causes malfunction.

After an initial reset, these flags are set to 0.

SWL0–SWL3

SWH0–SWH3

EISW0, EISW1

ISW0, ISW1

S1C62N81 TECHNICAL HARDWARE EPSON I-55

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Stopwatch Timer)

Stopwatch timer reset (0F9H D0)

This bit resets the stopwatch timer.

When 1 is written: Stopwatch timer reset

When 0 is written: No operation

Reading: Always 0

The stopwatch timer is reset when 1 is written to SWRST.

When the stopwatch timer is reset while running, operation

restarts immediately. Also,while stopped, the reset data is

maintained.

This bit is write-only, and is always 0 when read.

Stopwatch timer run/stop (0F9H D1)

This bit controls run/stop of the stopwatch timer.

When 1 is written: Run

When 0 is written: Stop

Reading: Valid

The stopwatch timer runs when 1 is written to SWRUN, and

stops when 0 is written.

When stopped, the timer data is maintained until the timer

next Run or is reset. Also, when the timer runs after being

stopped, the data that was maintained can be used to res-

ume the count.

If the timer data is read while running, a correct read may

be impossible because of the carry from the low-order bit

(SWL) to the high-order bit (SWH). This occurs if reading

has extended over the SWL and SWH bits when the carry

occurs. To prevent this, read after stopping, and then

continue running. Also, the stopped duration must be

within 976 µs (256 Hz, 1/4 cycle).

After an initial reset, this register is set to 0.

SWRST

SWRUN

I-56 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (BLD Circuit and Heavy Load Protection Function)

Battery Voltage Low Detection (BLD) Circuit

and Heavy Load Protection Function

The S1C62N81 Series have a built-in battery voltage low

detection (BLD) circuit and a heavy load protection function.

Figure 4.9.1 shows the configuration of the circuit.

BLD circuit

The BLD circuit monitors the conditions of the battery

voltage (supply voltage), and software can check whether the

battery voltage has dropped below the detecting voltage level

of the BLD circuit: 2.4 V when supply voltage is 3.0 V

(S1C62N81), or 1.2 V when supply voltage is 1.5 V

(S1C62L81). Registers BLDON (BLD control on/off) and

BLDDT (BLD data) are used for the BLD circuit. The soft-

ware can turn BLD operation on and off. When BLD is on,

the IC draws a large current, so keep BLD off unless it is.

Since battery voltage detection is automatically performed

by the hardware every 2 Hz (0.5 second) when the heavy

load protection function operates, do not permit the opera-

tion of the BLD circuit by the software in order to minimize

power current consumption.

Heavy load protection function circuit

When using the S1C62N81, the melody, lamp, and other

features impose a heavy load on the battery. Therefore, a

heavy load protection function is incorporated in case of a

voltage drop. Software-initiated switching can be effected in

heavy load protection mode. The HLMOD register controls

the heavy load protection function. Conversely, when the

BLD circuit detects a voltage drop below 1.2 V (S1C62L81),

or 2.4 V (S1C62N81), switching to heavy load protection

mode is carried out automatically.

This function enables 0.9 V operation (S1C62L81/62B81).

4.9

Configuration of BLD

circuit and heavy

load protection

function

S1C62N81 TECHNICAL HARDWARE EPSON I-57

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (BLD Circuit and Heavy Load Protection Function)

In the heavy load protection mode, the BLD circuit is acti-

vated intermittently by hardware. The cycle is 2 Hz and the

operating time is 122 µs (when the oscillation frequency,

fosc, of the oscillation circuit is 32.768 kHz). If the source

voltage is reduced by a heavy load while in the heavy load

protection mode, the rate of decrease can be detected by

hardware. The result is that the heavy load is lost. Even

when the heavy load protection mode is released by soft-

ware, the mode continues until the source voltage exceeds

the voltage detected by the BLD circuit. Therefore, malfunc-

tioning due to a reduced source voltage can be prevented

completely.

Vss

HLMOD

BLDDT

Vss

BLDON

BLD

circuit

Regulated

voltage

circuit

Data bus

Address 0FAH

BLD

sampling

control

Fig. 4.9.1

Configuration of BLD and

heavy load protection circuits

I-58 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (BLD Circuit and Heavy Load Protection Function)

The following explains the timing when the BLD circuit

writes the result of battery voltage detection to the BLDDT

The result of battery voltage detection is written to the

BLDDT register by the BLD circuit, and this data can be

read by the software to determine the battery voltage.

There are two methods, explained below, for executing the

detection by the BLD circuit.

(1)Sampling with HLMOD set to 1

When HLMOD is set to 1 and BLD sampling is executed,

the detection results can be written to the BLDDT register

with the following timing:

Immediately after sampling with the 2 Hz cycle output by

the oscillation circuit while HLMOD = 1 (sampling time is

122 µs in the case of fosc = 32.768 kHz).

Consequently, after HLMOD has been set to 1, the new

detection result is written in a 2 Hz.

(2)Sampling with BLDON set to 1

When BLDON is set to 1, BLD detection is executed. As

soon as BLDON is reset to 0, the result is loaded to in the

BLDDT register. To obtain a stable BLD detection result,

the BLD circuit must be on for at least 100 µs. So, to

obtain the BLD detection result, follow the programming

sequence below.

➀Set BLDON to 1

➁Maintain for 100 µs minimum

➂Set BLDON to 0

➃Read BLDDT

However, at 32 kHz for the S1C62N81 and S1C62L81,

the instruction cycles are long enough, so there is no

need to worry about maintaining 100 µs for BLDON = 1

in the software.

Operation of BLD

detection timing

S1C62N81 TECHNICAL HARDWARE EPSON I-59

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (BLD Circuit and Heavy Load Protection Function)

Notice that even if the BLD circuit detects a drop in the

supply voltage (1.2 V/2.4 V or less) and invokes the heavy

load protection mode, this will be the same as when the

software invokes the heavy load protection mode, in that the

BLD circuit will be sampled with a timing synchronized to

the 2 Hz output from the prescaler. If the BLD circuit

detects a voltage drop and enters the heavy load protection

mode, it will return to the normal mode once the supply

voltage recovers and the BLD circuit determines that the

supply voltage is 1.2 V/2.4 V or more.

The S1C62N81 has a heavy load protection function for

when the battery load becomes heavy and the supply voltage

drops, such as when a melody is played or an external lamp

lights. This functions works in the heavy load protection

mode. The normal mode changes to the heavy load protec-

tion mode in the following two cases:

➀When the software changes the mode to the heavy load

protection mode

➁When the BLD circuit detects a supply voltage less than

2.4 V (S1C62N81) or 1.2 V (S1C62L81), in which case the

mode is automatically changed to the heavy load protec-

tion mode

Based on the operation of the BLD circuit and the heavy

load protection function, the S1C62L81 obtains an opera-

tion supply voltage as low as 0.9 V. See the electrical char-

acteristics for the precision of voltage detection by the BLD

circuit.

In the heavy load protection mode, the internally regulated

voltage is generated by the liquid crystal driver supply

output, VL2, in order to operate the internal circuit. Conse-

quently, more current is consumed in the heavy load protec-

tion mode than in the normal mode. Unless necessary, do

not select the heavy load protection mode with the software.

Operation of heavy

load protection

function

Note Activation of the BLD circuit by software in the heavy load protec-

tion mode causes a malfunction. Avoid such activation if possible.

I-60 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (BLD Circuit and Heavy Load Protection Function)

Table 4.9.1 shows the control bits and their addresses for

the BLD circuit and the heavy load protection function.

Table 4.9.1 Control bits for BLD circuit and heavy load protection function

Control of BLD circuit

and heavy load

protection function

Heavy load protection mode on/off (0FAH D3)

When 1 is written: Heavy load protection mode on

When 0 is written: Heavy load protection mode off

Reading: Valid

When HLMOD is set to 1, the IC enters the heavy load

protection mode, and sampling control is executed for the

time the BLD circuit is on. The sampling timing is as fol-

lows:

Sampling in cycles of 2 Hz output by the oscillation circuit

while HLMOD = 1 (sampling time is 122 µs in the case of

fosc = 32.768 kHz).

When BLD sampling is done with HLMOD set to 1, the

results are written to the BLDDT register with the as follow-

ing timing:

Immediately on completion of sampling in cycles of 2 Hz

output by the oscillation circuit while HLMOD = 1.

Consequently, after HLMOD is set to 1, the new detected

result is written in 2 Hz.

In the heavy load protection mode, the consumed current

becomes larger. Unless necessary, do not select the heavy

load protection mode with the software.

HLMOD

Address Comment

D3 D2 D1 D0 Name SR 1 0

0FAH

HLMOD 0 BLDDT BLDON HLMOD

BLDDT

BLDON

0 ON OFF

Heavy load protection mode register

BLD data

BLD ON/OFF

RR/W R/W

Heavy

load

Battery

voltage

low

Normal

load

Battery

voltage

normal

S1C62N81 TECHNICAL HARDWARE EPSON I-61

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (BLD Circuit and Heavy Load Protection Function)

BLD control on/off (0FAH D0)

When 0 is written: BLD detection off

When 1 is written: BLD detection on

Reading: Valid

When this bit is written, the BLD detection on/off operation

is controlled. Large current is drawn during BLD detection,

so keep BLD detection off except when necessary. When

BLDON is set to 1, BLD detection is executed. As soon as

BLDON is reset to 0, the detected result is loaded into the

BLDDT register.

BLDON

BLD data (0FAH D1)

When 0 is read: Supply voltage ≥ Criteria voltage

When 1 is read: Supply voltage < Criteria voltage

When BLDDT is 1, the S1C62N81 enters the heavy load

protection mode. In this mode, the detection operation of

the BLD circuit is sampled in 2 Hz cycles and the respective

detection results are written to the BLDDT register.

BLDDT

I-62 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Analog Voltage Comparator)

Analog Voltage Comparator

The S1C62N81 Series have a built-in analog voltage com-

parator that compares two analog input voltages to produce

result data 0 or 1 in register CMPDT, according to the com-

pared voltages, CMPP and CMPM. The configuration of the

analog voltage comparator circuit is shown in Figure 4.10.1.

The voltage comparator has two analog voltage inputs,

CMPP (non-inverting input, +) and CMPM (inverting input,

-). When the voltage comparator is turned on by control

will be stored in register CMPDT. Therefore, the result in

the register will indicate whether CMPP is greater than

CMPM (when CMPDT = 1) or smaller than CMPM (when

CMPDT = 0).

4.10

Configuration of

analog voltage

comparator

CMPON

Output

control

Power

control

Data bus (D1)

Address (0FBH)

Data bus (D0)

Address (0FBH)

CMPP

CMPM

CMPDT

Fig. 4.10.1

Configuration of analog

voltage comparator circuit

S1C62N81 TECHNICAL HARDWARE EPSON I-63

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Analog Voltage Comparator)

Two registers, CMPON and CMPDT, are used in the analog

voltage comparator. The CMPON register switches the

analog voltage comparator on or off to reduce power con-

sumption. The CMPDT register indicates the result of

comparison of the CMPP and CMPM pins.

Writing 1 to the CMPON register turns on the comparator

circuit. After an initial reset, this bit is set to 0. Data in the

CMPON register is read-accessible or write-accessible. A

wait time of at least 3 ms is required for analog voltage

comparator to become stable after its power is turned on.

The comparator response time depends on the potential

difference between the CMPP and CMPM inputs.

When analog voltage comparator is turned on, the circuit

compares the two analog voltages from the CMPP and

CMPM inputs, then outputs the result as binary 0

(CMPM>CMPP) or 1 (CMPP>CMPM). The result of the com-

parison is read from the CMPDT register. Writing to the

CMPDT register is prohibited.

Data in the CMPDT register becomes 1 when CMPON is 0 (analog

voltage comparator circuit is off), and undefined when the CMPP

and / or CMPM input is disconnected. Avoid reading operation

under those conditions.

Operation of analog

voltage comparator

Note

I-64 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Analog Voltage Comparator)

Table 4.10.1 lists the control bits of the analog voltage

comparator and their addresses.

Control of analog

voltage comparator

Comparator on/off control (0FBH D0)

Switches the analog voltage comparator circuit to on or off.

When 1 is written: Comparator turns on

When 0 is written: Comparator turns off

Reading: Valid

After an initial reset, this bit is set to 0.

While analog voltage comparator is ON, the consumed current

becomes large. Unless necessary, do not turn on the analog

comparator.

Comparator data (0FBH D1)

Shows the result of comparing CMPP and CMPM.

When 1 is read: CMPP voltage is greater than

CMPM voltage

When 0 is read: CMPP voltage is smaller than

CMPM voltage

Writing: Invalid

This bit is undefined when the CMPP and/or CMPM input

pin is disconnected, and is 1 when CMPON is 0.

After an initial reset, this bit is set to 1.

CMPON

Table 4.10.1 Control bits of analog voltage comparator

Note

CMPDT

Address Comment

D3 D2 D1 D0 Name SR 1 0

0FBH

CSDC 0 CMPDT CMPON

LCD drive switch

Voltage comparator ON/OFF

Static

+ > -

Dynamic

- > +

Off

R/W R/W

CSDC

CMPDT

CMPON

Comparator's voltage condition:

1 = CMPP(+)input > CMPM(-)input,

0 = CMPM(-)input > CMPP(+)input

S1C62N81 TECHNICAL HARDWARE EPSON I-65

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

4.11 Melody Generator

Outline of melody

generator

The S1C62N81 Series has built-in melody generator. Out-

puts related to the melody function are generated from MO

terminal or R12 terminal. The following 3 types of melody

playing may be selected through the mask option:

(1)Piezo buzzer single terminal driving through the MO

terminal

The R12 output is set to DC output through the mask

option. Melody is output from the MO terminal alone.

This setting increases the number of externally fitted

parts to play the melody but since the R12 output may be

used as a common high-power current output, it is useful

when high-power current driving common output is

required.

(2)Piezo buzzer direct driving through the MO and R12

outputs

The R12 output is set to piezo direct driving through the

mask option. Reversed signal of the MO terminal output

signal is output from the R12 terminal. This allows the

piezo buzzer direct driving to materialize. This setting

makes it possible to keep the number of externally fitted

parts to the minimum.

(3)Envelope driving

The R12 output is set to the envelope function through

the mask option. Sound pressure of the playing is at-

tenuated with time, making it possible to implement a

fully expressive playing.

Refer to Chapter 5, "BASIC EXTERNAL WIRING DIAGRAM"

for the respective external wirings.

I-66 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

The characteristics of the melody generator are as follows:

(1)Size of the Melody ROM: 80 words

Basically, one note is equivalent to one word. Any num-

ber of melodies may be written as long as it is within 80

words. Data such as note length, intervals and end of

melody may be written.

(2)Size of Scale ROM: 15 scales

C3–C6# (without frequency booster) or C4–C7# (with

frequency booster) may be selected from among 15 scales.

The use of frequency booster may also be selected by the

mask option.

(3)Playing mode:

There are 3 playing modes.

➀One shot mode (only 1 melody is played)

➁Level hold mode (the same or a different melody is

continuously played)

➂Retrigger mode (forced change or termination of

melody)

(4)Tempo:

2 types may be selected from among 16 types through the

mask option.

(5)Playing speed:

Aside from the normal speed mode, 8 times, 16 times,

and 32 times speed mode may be controlled through

software. This function allows the generation of sound

effects.

S1C62N81 TECHNICAL HARDWARE EPSON I-67

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

The block diagram of the melody generator is shown in

Figure 4.11.1. The note and interval data of the melody to

be played is pre-written on the melody ROM. The interval

data of the melody ROM is used to specify the scale ROM

address and according to the scale ROM data read from it,

the interval generating circuit generates the interval. The

output is controlled at the melody output control circuit and

is output at the MO and R12 terminals. The note generator

is generated according to the melody ROM data. The output

is entered in the melody ROM address counter; every time

the playing of a note is completed, one address is

incremented. This results in continuous melody being

automatically played. The playing tempo is created by the

tempo generator based on the signal which divided the

oscillation frequency in the oscillation circuit. Through the

mask option, 2 types of tempo may be selected from among

16 types. Moreover, the division ratio of the divider may be

modified by software and 4 types of playing speed can be

implemented. Envelope function may also be added to the

output melody and R12 output may be implemented by

setting it to correspond with the envelope.

I-68 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

Fig. 4.11.1

Melody generator

block diagram

Frequency

booster

Interval

generating

circuit

Melody

output

control circuit

Scale

ROM

Melody

interrupt

generator

Address

counter Melody

ROM

End-of-melody

signal

generator

Controller Divider Tempo

generator Note

generator

To CPU

R12

32.768 kHz

Address bus

Data bus

Address bus

S1C62N81 TECHNICAL HARDWARE EPSON I-69

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

A detailed description of the circuits which form the melody

generator is provided below.

(a)Frequency booster

The configuration of the frequency booster is shown in

Figure 4.11.2. It is a circuit which raises the input

frequency (32.768 kHz) for the melody generator to 2

times the frequency. The output of this frequency

booster is provided with a switch through the mask

option; by selecting this switch, scale which can be

output may be changed. In other words, if frequency

booster output were selected for input to interval

generating circuit, interval can be created between C4 to

C7# and if 32.768 kHz were selected as is, interval can be

created between C3 to C6#.

Fig. 4.11.2

Frequency booster

Booster

32.768 kHz To interval

generating circuit

I-70 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

(b)Controller

The configuration of the controller is shown in Figure

4.11.3. The controller consists of a 4-bit register located

in the I/O RAM space and an ON/OFF control circuit and

controls the melody's ON/OFF, tempo selection, playing

speed selection. The ON/OFF control circuit controls the

turning ON/OFF of the melody playing by entering the

MELC register output and the signal from the end-of-

melody signal generator. The address of the 4-bit register

is "0F2H" and the meaning of each bit is as follows:

D0 (MELC):

This is the bit that controls the turning ON/OFF of the

melody playing. The controlling function of this bit

makes it possible to control the above-described 3

types of playing. Refer to "Playing mode" regarding the

method of control.

D1 (TEMPC):

This is the bit that selects the tempo. 2 types of tempo

selected by mask option may be changed. The timing

of tempo change is not done when data is written on

this bit but rather, when the next melody begins.

D2 and D3 (CLKC0 and CLKC1):

This is the bit that changes playing speed. By the

combination of CLKC0 and CLKC1, 4 types of playing

speed may be selected. The playing speed for the

selectable tempo listed in Table 4.11.7 is the normal

speed; playing speeds which are 8, 16 and 32 times

the normal speed may also be selected. This is useful

in generating sound effects. For details, see "Playing

tempo".

Note Since playing speed is modified simultaneously with data writing

on these bits, caution must be observed when operating these

bits in the middle of a playing.

S1C62N81 TECHNICAL HARDWARE EPSON I-71

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

Fig. 4.11.3

Controller

(c)Address register

The configuration of the melody ROM address registers is

shown in Figure 4.11.4. It consists of the 7-bit register in

the I/O RAM space. The addresses are "0F0H" and

"0F1H". The data of these registers indicate the ad-

dresses of the melody ROM which become the addresses

of the melody ROM when the melody is started. These

melody ROM addresses are written to the melody ROM

address counter when the melody playing begins, i.e.,

before the the melody playing begins, the desired melody

may be played from among the melodies written in the

melody ROM by setting data on these registers.

MELC

(D0)

ON/OFF

control

circuit

TEMPC

(D1)

CLKC0

(D2)

CLKC1

(D3)

Data bus

Address "0F2H"

Playing speed

control signal

Tempo control

signal

ON/OFF

control signal

End-of-melody signal

I-72 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

Fig. 4.11.5

Address counters

Note Caution must be observed because when an address from

"50H" to "7FH" is set on the address register, since the address

does not exist in the melody ROM hardware-wise, all melody

ROM output will become "1" and silent notes equivalent to 32

notes will be played.

(d)Address counter

The configuration of the melody ROM address counters is

shown in Figure 4.11.5. It consists of a counter in which

note playing end signal generated from the note generator

is entered and which increases the melody ROM ad-

dresses by 1 address every time a note playing is com-

pleted. Moreover, when a melody playing begins, address

This causes the address set in the address register to

specify the melody ROM address.

MAD0

(D0)

MAD1

(D1)

MAD2

(D2)

MAD3

(D3)

Data bus

Address "0F0H" To Address counter

MAD4

(D0)

MAD5

(D1)

MAD6

(D2)

Address "0F1H"

Fig. 4.11.4

Address register

MAD0

Melody ROM Address

MAD1

MAD2

MAD3

MAD4

MAD5

MAD6

Note playing

end signal

S1C62N81 TECHNICAL HARDWARE EPSON I-73

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

(e)Melody ROM

The melody ROM is a mask ROM with 80 words × 9 bits

capacity in which data of the melody to be played (note,

interval, end-of-melody, etc.) is stored beforehand. Any

number of melodies may be stored as long as the total

number of notes is within 80 words (basically, 1 note/

word). Details regarding the melody ROM configuration,

etc., can be found in next ection, "Melody data".

Note When the melody ROM is set with a non-existent address

("50H" and above), all of its output will become "1" (i.e., 32

silent notes) by the hardware.

(f) Divider

The configuration of the divider is shown in Figure

4.11.6. It is a circuit that divides the clock (32.768 kHz)

which is input in the melody generator and inputs the

divided clock into the tempo generator. The dividing ratio

may be controlled by software. The data of the "CLKC0"

and "CLKC1" registers in the above-mentioned controller

is input and the dividing ratio will differ according to the

value of the input data. The dividing ratio and playing

speed for the combinations of CLKC0 and CLKC1 values

are shown in Table 4.11.1. The "normal" speed in the

playing speed column refers to the playing speed by

which the tempo listed in Table 4.11.7 may be imple-

mented. playing speeds 8 times (the normal speed) or

more are useful for generating sound effects.

Table 4.11.1

Dividing ratio

1/512

1/64

1/32

1/16

Normal

8 times

16 times

32 times

CLKC1 CLKC0 Dividing

Ratio Playing

Speed

I-74 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

32.768 kHz 1/2

divider 1/2

divider 1/8

divider

CLKC0

CLKC1

To tempo

generator

(g)Tempo generator

The configuration of the tempo generator is shown in

Figure 4.11.7. The tempo generator is a circuit which

generates the 2 types of tempo selected by mask option

and consists of the 4-bit counter in which the output

signal from the divider is input and the 4 switches which

set their respective bit. The 4-bit counter output serves

as the note generator input. The 4 switches are auto-

matically set to generate the 2 types of tempo selected by

mask option. Bit settings and the corresponding tempo

generated are shown in Table 4.11.2. On the other hand,

the relationship between the 2 types of tempo selected by

mask option and switch settings are shown in Table

4.11.3. For example, if the respective bit values of the 2

types of tempo selected by mask option are "1" for

TEMPC = 0 and "0" for TEMPC = 1, the switch setting for

this bit combination will be TEMPC (reverse signal of the

TEMPC register output).

Fig. 4.11.6

Divider

S1C62N81 TECHNICAL HARDWARE EPSON I-75

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

Table 4.11.2

Counter setting and tempo

Table 4.11.3

Tempo and switch setting

TS2 0

TS1 0

TS0 30

34.3

36.9

43.6

53.3

68.6

120

160

240

480

TS3

1/2

divider 1/2

divider To note generator

Divider

output

signal 1/2

divider

TEMPC

Mask option

TS3TS2TS1TS0

TEMPC

Fig. 4.11.7

Tempo generator

TEMPC=0

TEMPC=1 Pull down

TEMPC

Pull up

Switch Setting

I-76 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

(h)Note generator

This is a generator which counts the tempo generator

output and creates various notes. Its configuration is

shown in Figure 4.11.8. It consists of counters in which

3 bits can be set. Each counter is set by the 3 bits (D5–

D7) from the melody ROM causing the counter dividing

ratio to change and hence various notes are generated.

The bit settings and the corresponding notes generated

are shown in Table 4.11.4. The counter output becomes

the note playing end signal and the address of the melody

ROM is incremented 1 step at a time.

Table 4.11.4

Note data and notes

D5 Note

Tempo generator

output signal 1/2

divider 1/2

divider

Note playing

signal

Melody ROM output

(D5–D7)

Fig. 4.11.8

Note generator

S1C62N81 TECHNICAL HARDWARE EPSON I-77

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

(i) Scale ROM

This is a mask ROM in which 15 scale types which have

been optionally selected and created from either C3–C6#

(available output frequency range: 4,096 Hz–125.5 Hz;

without frequency booster) or C4–C7# (available output

frequency range: 8,192 Hz–251.1 Hz; with frequency

booster) are stored beforehand. The 15 available ad-

dresses are "00H"–"0EH". Word length is 8 bits; the data

written on them and the corresponding scale (frequency)

generated are shown in Tables 4.11.5 (a) and (b). The

maximum value which may be written as a data is "FDH".

The address is specified by the melody ROM output and

the output is entered in the interval generating circuit.

Note Bear in mind that the range of the data which can be written on

the scale ROM is from "00H" to "FDH". If any data beyond this

range is written, the interval generating circuit will not function

normally.

I-78 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

Table 4.11.5 (a) Scale ROM data and interval (without frequency booster)

Scale

Data Scale ROM Code

Hex.

Frequency

(Hz) Dividing

Ratio Absolute

Error (%) Standard

Frequency (Hz)

C3#

D3#

F3#

G3#

A3#

C4#

D4#

F4#

G4#

A4#

C5#

D5#

F5#

G5#

A5#

C6#

128

135.405

143.719

152.409

161.419

170.667

181.039

191.626

203.528

215.579

227.556

240.941

256

270.810

287.439

303.407

321.255

341.333

360.088

385.506

404.543

431.158

455.111

481.882

512

546.133

574.877

606.815

642.510

682.667

728.178

762.047

819.200

862.316

910.222

963.765

1024

1092.267

1/128

1/121

1/114

1/107

1/101

1/96

1/90

1/85

1/80

1/76

1/72

1/68

1/64

1/60

1/57

1/54

1/51

1/48

1/45

1/42

1/40

1/38

1/36

1/34

1/32

1/30

1/28

1/27

1/25

1/24

1/22

1/21

1/20

1/19

1/18

1/17

1/16

1/15

1/2

103

102

1/2

-0.152

0.031

0.024

0.092

-0.113

0.010

-0.030

0.167

0.143

-0.226

-0.287

-0.153

0.031

-0.339

-0.400

-0.113

-0.542

0.503

-0.453

0.144

-0.226

-0.287

0.675

0.031

-0.339

-0.400

-0.113

0.563

-0.668

0.787

0.144

-0.226

-0.287

0.675

128

135.611

143.675

152.218

161.270

170.860

181.019

191.783

203.187

215.270

228.070

241.632

256

271.222

287.350

304.436

322.540

341.720

362.038

383.566

406.374

430.540

456.140

483.264

512

542.444

574.700

608.872

645.080

683.440

724.076

767.132

812.748

861.080

912.280

966.528

1024

1084.888

S1C62N81 TECHNICAL HARDWARE EPSON I-79

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

Table 4.11.5 (b) Scale ROM data and interval (with frequency booster)

Scale

Data Scale ROM Code

Hex.

Frequency

(Hz) Dividing

Ratio Absolute

Error (%) Standard

Frequency (Hz)

C4#

D4#

F4#

G4#

A4#

C5#

D5#

F5#

G5#

A5#

C6#

D6#

F6#

G6#

A6#

C7#

256

270.810

287.439

304.819

322.837

341.333

362.077

383.251

407.056

431.158

455.111

481.882

512

541.620

574.877

606.815

642.510

682.667

720.176

771.012

809.086

862.316

910.222

963.765

1024

1092.267

1149.754

1213.630

1285.020

1365.333

1456.356

1524.093

1638.400

1724.632

1820.444

1927.529

2048

2194.533

1/128

1/121

1/114

1/107

1/101

1/96

1/90

1/85

1/80

1/76

1/72

1/68

1/64

1/60

1/57

1/54

1/51

1/48

1/45

1/42

1/40

1/38

1/36

1/34

1/32

1/30

1/28

1/27

1/25

1/24

1/22

1/21

1/20

1/19

1/18

1/17

1/16

1/15

1/2

103

102

1/2

-0.152

0.031

2.448

0.092

-0.113

0.011

-0.082

0.168

0.143

-0.226

-0.287

-0.152

0.031

-0.339

-0.400

-0.113

-0.541

0.503

-0.453

0.143

-0.226

-0.287

0.676

0.031

-0.339

-0.399

-0.113

0.563

-0.667

0.788

0.143

-0.226

-0.287

0.676

256

271.222

287.350

304.436

322.540

341.720

362.038

383.566

406.374

430.540

456.140

483.264

512

542.444

574.700

608.872

645.080

683.440

724.076

767.132

812.748

861.080

912.280

966.528

1024

1084.888

1149.400

1217.748

1290.160

1366.880

1448.152

1534.264

1625.496

1722.160

1824.560

1933.056

2048

2169.776

I-80 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

(j) Interval generating circuit

The interval generating circuit generates the interval

(frequency) corresponding to the scale ROM output. Its

configuration is shown in Figure 4.11.9. Using the input

clock (32.768 kHz) to the melody generator or the 8-bit

divider with the booster output (65.536 kHz) as input

clock, dividing ratios (1/8–1/261) set by the scale ROM

output (S0–S7) can be attained. The divider output

passes through the output controller and becomes sound

output. Scales which can be output are C3–C6# (avail-

able output frequency range: 4,096 Hz–125.5 Hz; without

frequency booster) or C4–C7# (available output frequency

range: 8,192 Hz–251.1 Hz; with frequency booster). The

dividing ratio may be derived from S0–S7 values which

are the scale ROM output using the following equation:

N (dividing ratio) = (/S7 × 26 + /S6 × 2 5 + /S5 × 24 + /S4 × 23 + /S3

× 22 + /S2 × 21 + /S1 × 20 +3) × 2 + S0

(Note: /SX = reversed value of SX)

Example:

(S7, S6, S5, S4, S3, S2, S1, S0) = (1, 1, 1, 0, 0, 1, 0, 0),

then,

N = (0 × 26 + 0 × 25 + 0 × 24 + 1 × 23 + 1 × 22 + 0 × 21 + 1 × 20

+3) × 2 + 0 = 32

In other words, if the input clock were 32.768 kHz,

the output will be 32,768/32 = 1,024 Hz (C6).

The selection of input clock may be done by changing the

switch (by mask option) explained in the section on

booster.

Fig. 4.11.9

Interval generating circuit

Divider (dividing ratio: 1/8–1/261)

Booster

output To melody output

control circuit

S0–S7

Scale ROM output (8 bits)

S1C62N81 TECHNICAL HARDWARE EPSON I-81

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

(k)End-of-melody signal generator

This is a circuit that receives the end-of-melody data

written on the melody ROM and generates the end-of-

melody signal which synchronized with the end of a note

playing. The output is entered into the controller and the

melody interrupt generator and becomes the source

signal which informs the end of a melody.

(l) Melody interrupt generator

The configuration of the melody interrupt generator is

shown in Figure 4.11.10. It is a circuit that receives the

end-of-melody signal from the end-of-melody signal

generator and generates the melody interrupt signal

which informs the CPU that a certain melody has been

completed. At the same time, it sets an interrupt factor

flag the timing of which is shown in Figure 4.11.11. The

interrupt factor flag becomes valid approximately 7.8 ms

(in case of normal speed) after the end-of-melody signal is

generated. The interrupt factor flag may be read out by

software and is reset simultaneously with the read out.

The register address is "ECH D0". It can also be masked

for the interrupt signal and masking can be controlled by

software. The mask register address is "E7H D0".

Fig. 4.11.10

Melody interrupt generator

IMEL

EIMEL

Address "0ECH"

Address "0E7H"

Data bus

End-of-melody signal

Interrupt signal

I-82 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

Valid

Approx. 7.8 ms

PlayingPlaying

End-of-melody

signal

Melody interrupt

signal

Interrupt factor

flag

Note Reading out the interrupt request flag or writing on the mask

ited)" state. Otherwise, misoperation may result.

(m)Melody output control circuit

This is a circuit that determines the form of melody

playing (piezo buzzer direct driving and addition of enve-

lope function) according to the mask option selection.

(n) Melody output terminal (M0 and R12)

This is a terminal which produces melody during playing.

Its output configuration and output waveform are shown

in Figure 4.11.12. The configuration differs if the mask

option selection were R12.

Fig. 4.11.11

Interrupt generation timing

S1C62N81 TECHNICAL HARDWARE EPSON I-83

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

Fig. 4.11.12 Melody terminal output configuration and output waveform

(1) R12: DC output (2) R12: Melody reverse output (3) R12: With envelope function

(1)R12: DC output

Melody is output from the MO terminal and from the

R12 terminal, data written on the "R12" register is

output. The MO terminal is a complementary output

terminal and goes high when melody is not played.

Complementary output or Pch open-drain output may

be selected for the R12 terminal by mask option.

(2)R12: Melody reverse output

Using MO and R12 terminals, the piezo buzzer may be

directly driven. During playing, reverse signal of the

MO terminal is output from the R12 terminal. Both

terminals go high when melody is not being played.

The output configuration of both terminals becomes

complementary.

R12

(with external

capacitor)

R12

output

Melody signal

Vss

R12

output

Melody signal

V DD

Vss

R12

Attack signal

Melody signal

Analog switch

Vss

I-84 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

(3)R12: With envelope function

Envelope function can be implemented by connecting

an external capacitor to the R12 terminal. Melody is

output from the MO terminal and the signal which will

recharge the external capacitor will be output from the

R12 terminal. The R12 electric potential will turn out

supplying the negative electric potential of the MO

terminal output and when the melody signal goes

high, it will pass the analog switch and will be sup-

plied to the MO terminal. For details regarding the

envelope function, refer to "Envelope function".

Melody data • Melody ROM

The melody ROM has an 80-word capacity, the length of a

word being 9 bits. Basically, data of 1 note is stored in 1

word. These data are continuously read out by the hard-

ware and melody is played. The 4 types of data which

may be written as 1-note data are as follows:

(1)Interval data

(2)Note data

(3)End data

(4)Attack data

When melody playing starts, the start address is specified

with the address written on the address register. The

melody ROM address is then automatically increased by

the address counter one step at a time and melody is

played. The melody automatically stops at the point

where the end-of-melody data written on the melody ROM

is read out by the hardware. At the same time, interrupt

flag is set and interrupt for the CPU is generated.

Fig. 4.11.13

Data format of

the melody ROM

D8 D7 D6 D5 D4 D3 D2 D1 D0

Attack

data

Note data Scale data

End

data

S1C62N81 TECHNICAL HARDWARE EPSON I-85

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

Since only melody start address setting and melody start

control may be controlled by software, optional melodies

which have been written on the melody ROM can easily

be played by lessening the load of the software.

The format of the data contained in a melody ROM word

is shown in Figure 4.11.13. These melody data are

explained in details below.

• Note data (D5–D7)

Note data are data which indicate the notes to be used.

As shown in Figure 4.11.13, note data are written on 3

bits: D5–D7. There are 8 types of notes which can be

used in the S1C62N81 Series and the corresponding 3

note data bits are shown in Table 4.11.6. Although notes

shorter than 32 notes may not be played, notes longer

than 2 notes may be played by operating the above-

mentioned attack note. This procedure is explained in

the section on attack data.

Table 4.11.6

Note data and notes

D7 0

D6 0

D5 Note

I-86 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

• Scale data (D1–D4)

Intervals to be used are pre-written on the scale ROM.

There are 15 scale ROM addresses which can be used:

"00H" to "0EH". The addresses are written on the 4 bits

(D1–D4; see Figure 4.11.13) which serve as interval data

area. Intervals written on the interval ROM address which

has been specified with the interval data (refer to Table

4.11.5) are generated at the interval generating circuit.

Although the scale ROM addresses are only from "00H" to

"0EH", "0FH" also exists in the hardware and is set for

silent notes. Because of this, writing "0FH" on the

melody ROM interval data area will result in the playing

of silent notes. The length of a silent note depends on the

note data written on the same word.

• Attack data (D8)

The attack data is a 1-bit data which determines whether

or not to make the break between notes clear. In each

melody first word, set this data to "1". Otherwise, there

will be no melody play even if the user starts play.

If envelope function is not available, writing "1" for this

bit will produce an approximately 12 ms rest every time

the melody ROM address increases by 1 step (i.e., at the

break of the playing of different notes). This is particu-

larly useful when the same notes follow one another. As

a rule, "1" is written on the attack bit of all words. How-

ever, when long notes other than those listed in Table

4.11.6 are desired, they can be implemented by linking

several words of the same interval to a continuous ad-

dress and at the same time setting the attack bit to "0".

On the other hand, when envelope function is available,

setting this bit to "1" will cause the capacitor for the

envelope function which is externally installed to be

recharged when the playing starts and increase the

sound pressure of the playing. Moreover, when this bit is

set to "0", since the capacitor will be continuously dis-

charged without being recharged, the sound pressure of

the playing will continue to diminish. The principle of the

envelope function is explained in details in the next

section.

S1C62N81 TECHNICAL HARDWARE EPSON I-87

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

• End data (D0)

This is 1-bit data which indicate the end of a set of played

melody. If this bit were written with "1", when the word

is played, end-of-melody signal will be generated at the

end-of-melody signal generator and will then be input to

the melody interrupt generator and the controller. This

signal is received at the melody interrupt generator which

issues interrupt request to the CPU and generates inter-

rupt flag. Moreover, the controller stops the playing

when the melody ON/OFF control register is set to "0"

when the signal is received and either repeats the same

melody or continuously plays new melodies when it is set

to "1". By dividing the 80-word melody ROM with end-of-

melody data, any number of melodies may be written as

long as it is within the capacity. Also, a melody which

will be repeatedly used need be written only once, i.e.,

there is no need to write the melody for as many number

of times you wish to repeat it. Repeated playing can be

easily accomplished by merely specifying the playing start

address repeatedly through the software. Control of

playing is explained in details in "Control of playing".

Playing of silent note Silent note may be played by writing "0FH" on the melody

ROM interval data. The length of the silent note is the same

as the length of the note written on the same word. For

details, refer to "Melody data".

I-88 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

Envelope function The S1C62N81 Series may be added with envelope function

for melody playing by mask option. The IC internal circuit

when the envelope function is valid and the external circuit

required is shown in Figure 4.11.14. The IC internal setting

is done by mask option and the following need to be exter-

nally installed:

- piezo buzzer sounding body;

- booster coil for raising the sound pressure of the playing;

- PNP bipolar transistor to drive the sounding body (piezo

buzzer);

- capacitor for implementing smooth sound pressure

attenuation; and

- resistor for controlling the power current discharge of the

capacitor.

The output waveform when envelope function is shown in

Figure 4.11.15. The attack signal indicated in the diagram

will go high ("H" level) when the playing of the word starts if

the attack data written on the melody ROM were "1". The

pulse width is approximately 12 ms. The ATK (attack) signal

recharges the externally installed capacitor and the R12

terminal output level will be recharged up to the power

voltage as shown in Figure 4.11.15. This will result in the

MO terminal output amplitude becoming the power voltage

since they (R12 and MO terminals) are wired together inside

the IC as shown in Figure 4.11.14. The sound pressure of

the melody played then will be maximum. Henceforth,

because the capacitor connected to the R12 terminal is

discharged as the base current of the externally installed

transistor as time passes, the base current will drop and the

playing sound pressure will attenuate with the passing of

time. The MO terminal output waveform is shown in Figure

4.11.15. The MO terminal output amplitude will decrease

with capacitor discharge. This is the principle of the enve-

lope function.

S1C62N81 TECHNICAL HARDWARE EPSON I-89

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

Fig. 4.11.14

Configuration of the

envelope function

Fig. 4.11.15

Envelope output waveform

Attack signal

R12 pin output

Melody signal

MO pin output

R12

Vss

Attack signal

Melody signal

Analog switch

Piezo

buzzer Booster

coil

PNP

Transistor

Capacitor

S1C62N81

I-90 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

Playing tempo In the S1C62N81 Series, 2 types of melody playing tempo

may be selected from among 16 types by mask option.

Tempos which may be selected are shown in Table 4.11.7

(see also "Tempo generator"). The proper use of the 2 types

of tempo selected is specified through the software. The 2

types of tempo which may selected are: the tempo to be

played when "0" is written on the TEMPC register of the

controller and the tempo to be played when "1" is written on

the said register.

Note Changing the 2 types of tempo selected by mask option is not done

on the spot when data is written on the TEMPC register but rather,

the tempo is changed when a new melody is played after the data

has been written, i.e., the tempo cannot be changed in the middle

of a melody playing.

Table 4.11.7

Tempos available

for selection

TS2 0

TS1 0

TS0 30

34.3

36.9

43.6

53.3

68.6

120

160

240

480

TS3

S1C62N81 TECHNICAL HARDWARE EPSON I-91

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

Furthermore, 4 types of playing speed may be selected in

the S1C62N81 Series. The selection can be done through

the software and control is performed by writing data on

CLKC0 and CLKC1 registers of the controller. The data

written on the registers and the corresponding playing speed

are shown in Table 4.11.8. By writing "0" on CLKC0 and

CLKC1, normal speed tempo (i.e., tempo selected by mask

option) may be played. playing at 8 times, 16 times and 32

times of the normal speed is useful for producing sound

effects for games and animal sounds.

Table 4.11.8

Playing speed

Changing the playing speed is instantly accomplished by writing

data on CLKC0 and CLKC1 registers. When speed need not be

changed in the middle of a melody, write the playing speed data

upon completion of a melody playing, i.e., during rest.

Normal

8 times

16 times

32 times

CLKC1 CLKC0 Playing Speed

Note

I-92 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

Playing mode The S1C62N81 Series have 3 modes for melody playing: one

shot mode, level hold mode and retrigger mode. The control

of these modes is done through operation of the MELC

(a)One shot mode

In this mode, only one specified melody is played; playing

automatically stops when the melody ends. Control

procedures are as follows:

(1)Set the melody ROM address (start address) of the

desired melody in the address register (MAD0–MAD6).

(2)Immediately after writing "1" (before the melody play-

ing ends), write "0" on the MELC register.

The above operation will allow only one melody to be

played. Melody playing is started from the address writ-

ten on the address register, by writing "1" on the MELC

of-melody data is "1") ends, end-of-melody signal is gener-

ated and interrupt request to the CPU and interrupt flag

are generated in the melody interrupt generator. At this

point, since "0" has previously been written on the MELC

ing is generated in the controller and hence, playing will

stop.

The relationship between MELC register value and play-

ing output is shown in Figure 4.11.16.

Fig. 4.11.16

One shot mode

100

Approx. 125 ms

Generation of

melody interrupt

PlayingPlaying

"MELC"

S1C62N81 TECHNICAL HARDWARE EPSON I-93

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

Note Bear in mind that playing will start approximately 125 ms (in

case of normal speed) after writing "1" on the MELC register.

(b)Level hold mode

Repetition of the same melody or continuous playing of

different melodies is possible in this mode. The operating

procedure are as follows:

(1)Set the melody ROM address (start address) of the

desired melody in the address register (MAD0–MAD6).

(2)Write "1" on the MELC register.

(3)Immediately after procedure (2) above (before the

melody being played ends), write the start address of

the second melody on the address register (MAD0–

MAD6). When repeating the same melody, there is no

need to write anew on the address register.

(4)Since melody interrupt will be generated when the first

melody ends, write the address for the third melody on

the address register (MAD0–MAD6) with the interrupt

routine. This operation must be completed before the

second melody ends. When the same melody is to be

repeatedly played, there is no need for this operation.

The optional melody in the melody ROM may continu-

ously be played by repeating the above steps.

(5)To stop playing, write "0" on the MELC register while

the last melody is being played. This will cause the

playing to be automatically stopped when playing of

the last melody is completed.

I-94 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

The relationship between MELC register value and play-

ing output is shown in Figure 4.11.17.

(c)Retrigger mode

This playing mode is for modifying or stopping the melody

forcedly in the middle of playing. Its operating procedure

is as follows:

(1)In the middle of a melody playing, write the melody

ROM address of the next melody to be played on the

address register (MAD0–MAD6).

(2)Change the MELC register setting from "0" to "1". At

this point, the played melody will be forcedly changed.

(3)After this operation, the 3 types of playing mode may

be selected freely again.

To stop a melody in the middle of its playing is also

implemented by employing this mode. The operation is

as follows:

(1)In the middle of a melody playing, set the melody ROM

address written with silent notes on the address regis-

ter (MAD0–MAD6).

(2)Change the MELC register setting from "0" to "1" and

then to "0" again.

Fig. 4.11.17

Level hold mode

Approx. 125 ms

Generation of

melody interrupt

Melody

Playing

"MELC"

Melody

....

Melody

n-1 Melody

S1C62N81 TECHNICAL HARDWARE EPSON I-95

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

With the above operation, the melody being played will be

forced to change into silent note playing; as soon as the

playing of the silent notes is completed, the playing will

automatically stop. In the above operation (2), writing

operation for the last "0" must be done before the playing

of silent notes ends.

The relationship between MELC register value and play-

ing output is shown in Figure 4.11.18.

Bear in mind that when melody playing is forcedly modified with

the above operations, playing of the modified melody will start

approximately 125 ms (in case of normal speed) after "1" has

been written on the MELC register.

Note

Fig. 4.11.18

Retrigger mode

Approx.

125 ms

Generation of

melody interrupt

Playing

"MELC"

Melody 1 Melody 2

Approx.

125 ms

I-96 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

Control of the

melody generator

Operation of registers for melody control is explained in this

section.

Table 4.11.9 Control bits of melody generator

Address Comment

D3 D2 D1 D0 Name SR 1 0

0E7H

0 0 0 EIMEL

EIMEL 0 Enable Mask

Interrupt mask register (melody)

R/W

0ECH

0 0 0 IMEL

IMEL 0

Interrupt factor flag (melody)

Yes No

0F0H

0F1H

0F2H

MAD3 MAD2 MAD1 MAD0

0 MAD6 MAD5 MAD4

CLKC1 CLKC0 TEMPC MELC

R/W

MAD3

MAD2

MAD1

MAD0

MAD6

MAD5

MAD4

Melody ROM address (AD6, MSB)

Melody ROM address (AD5)

Melody ROM address (AD4)

CLKC1

CLKC0

TEMPC

MELC

CLKC1(0)&CLKC0(0) : melody speed 1

CLKC1(0)&CLKC0(1) : melody speed 8

CLKC1(1)&CLKC0(0) : melody speed 16

CLKC1(1)&CLKC0(1) : melody speed 32

Tempo change control

Melody control ON/OFF

Melody ROM address (AD3)

Melody ROM address (AD2)

Melody ROM address (AD1)

Melody ROM address (AD0, LSB)

High

Low

High

Low

High

Low

OFF

R/W

S1C62N81 TECHNICAL HARDWARE EPSON I-97

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

–MELC: Melody ON/OFF Control Register (F2H D0)

By operating this register, control of the melody playing

ON/OFF and the 3 types playing modes—one shot mode,

level hold mode and retrigger mode—can be performed.

When 1 is written: Playing starts

When 0 is written: Playing stops

Reading: Valid

–TEMPC: Tempo Control Register (F2H D1)

By operating this register, 1 type of tempo may be se-

lected from the 2 types previously selected by mask

option.

When 1 is written: Selects the tempo of TEMPC1

selected by mask option

When 0 is written: Selects the tempo of TEMPC0

selected by mask option

Reading: Valid

Note Changing the tempo through this register is not possible in the

middle of a melody playing even if this register is operated while

a melody is being played. Change of melody will synchronize

with the playing of a new melody.

–CLKC0: Playing Speed Control Register (F2H D2)

CLKC1: Playing Speed Control Register (F2H D3)

By operating these registers, playing speed of a melody

may be changed. The combination of CLKC0 and CLKC1

4.11.10.

When 1 is written: 1

When 0 is written: 0

Reading: Valid

I-98 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

Table 4.11.10

Playing speed

Note Playing speeds are changed the moment these registers are

operated. Take caution when operating these registers in the

middle of a melody playing.

–MAD0–MAD6: Address Registers

(F0H D0–D3 and F1H D0–D2)

These registers are used to set the melody playing start.

By operating the "MELC" register, when playing of a new

melody starts, the addresses set in these registers are

read by the melody ROM address counter and become the

melody start addresses.

When 1 is written: 1

When 0 is written: 0

Reading: Valid

When these registers are written with "50H" –"7FH", since these

addresses do not exist in the melody ROM, the hardware will

cause silent notes equivalent to 32 notes to be played and so,

caution must be observed.

–EIMEL: Melody Interrupt Mask Register (E7H D0)

By operating this register, melody interrupt can be

masked.

When 1 is written: Interrupt is valid

When 0 is written: Interrupt is invalid

Reading: Valid

Normal

8 times

16 times

32 times

CLKC1 CLKC0 Playing Speed

Note

S1C62N81 TECHNICAL HARDWARE EPSON I-99

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

Note Be sure to operate this register in the "DI (interrupt not allowed)"

state. Otherwise, it may result in misoperation.

–IMEL: Melody Interrupt Factor Flag (ECH D0)

The moment the melody playing (i.e., playing of the

address the end-of-melody data in the melody ROM of

which is "1") ends, a flag is set on this register. Due to

this, the end of a melody playing can be known by read-

ing out this register. This register is also reset by the

hardware after the readout.

When 1 is read: Interrupt generation; 0 after readout

When 0 is read: Interrupt is not generated

Writing: Invalid

I-100 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Interrupt and HALT)

Interrupt and HALT

The S1C62N81 Series provide the following interrupt set-

tings, each of which is maskable.

External interrupt: Input interrupt (two)

Internal interrupt: Timer interrupt (one)

Stopwatch interrupt (one)

Melody interrupt (one)

To enable interrupts, the interrupt flag must be set to 1 (EI)

and the necessary related interrupt mask registers must be

set to 1 (enable). When an interrupt occurs, the interrupt

flag is automatically reset to 0 (DI) and interrupts after that

are inhibited.

When a HALT instruction is input, the CPU operating clock

stops and the CPU enters the halt state. The CPU is reacti-

vated from the halt state when an interrupt request occurs.

Figure 4.12.1 shows the configuration of the interrupt

circuit.

4.12

S1C62N81 TECHNICAL HARDWARE EPSON I-101

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Interrupt and HALT)

IMEL

EIMEL

KCP10

EIK10

K10

KCP00

EIK00

K00

KCP01

EIK01

K01

KCP02

EIK02

K02

KCP03

EIK03

K03

ISW0

EISW0

ISW1

EISW1

IT2

EIT2

IT8

EIT8

IT32

EIT32

IK1

IK0

Highest

Lowest

Program counter of CPU

(four low-order bits)

Interrupt vector

10A

108

106

104

102

Interrupt factor flag

Interrupt mask register

Input comparison register

Address Priority

Interrupt flag

INT

(Interrupt request)

Fig. 4.12.1 Configuration of interrupt circuit

I-102 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Interrupt and HALT)

Table 4.12.1 shows the factors that generate interrupt

requests.

The interrupt factor flags are set to 1 depending on the

corresponding interrupt factors.

The CPU is interrupted when the following two conditions

occur and an interrupt factor flag is set to 1.

• The corresponding mask register is 1 (enabled)

• The interrupt flag is 1 (EI)

The interrupt factor flag is a read-only register, but can be

reset to 0 when the register data is read.

After an initial reset, the interrupt factor flags are reset to 0.

Read the interrupt factor flags only in the DI status (interrupt flag =

0). A malfunction could result from a read during the EI status

(interrupt flag = 1).

Interrupt Factor

Clock timer 2 Hz falling edge

Clock timer 8 Hz falling edge

Clock timer 32 Hz falling edge

Stopwatch timer

1 Hz falling edge

Stopwatch timer

10 Hz falling edge

Input data (K00–K03)

Rising or falling edge

Input data (K10)

Rising or falling edge

Melody generator

End of melody

Interrupt Factor Flag

IT2 (0EFH D2)

IT8 (0EFH D1)

IT32 (0EFH D0)

ISW1 (0EEH D1)

ISW0 (0EEH D0)

IK0 (0EDH D0)

IK1 (0EDH D1)

IMEL (0ECH D0)

Interrupt factors

Note

Table 4.12.1

Interrupt factors

S1C62N81 TECHNICAL HARDWARE EPSON I-103

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Interrupt and HALT)

The interrupt factor flags can be masked by the correspond-

ing interrupt mask registers. The interrupt mask registers

are read/write registers. They are enabled (interrupt en-

abled) when 1 is written to them, and masked (interrupt

disabled) when 0 is written to them. After an initial reset,

the interrupt mask register is set to 0.

Table 4.12.2 shows the correspondence between interrupt

mask registers and interrupt factor flags.

Interrupt Mask Register

EIT2 (0EBH D2)

EIT8 (0EBH D1)

EIT32 (0EBH D0)

EISW1 (0EAH D1)

EISW0 (0EAH D0)

EIK03 * (0E8H D3)

EIK02 * (0E8H D2)

EIK01 * (0E8H D1)

EIK00 * (0E8H D0)

EIK10 * (0E9H D0)

EIMEL (0E7H D0)

Interrupt Factor Flag

IT2 (0EFH D2)

IT8 (0EFH D1)

IT32 (0EFH D0)

ISW1 (0EEH D1)

ISW0 (0EEH D0)

IK0 (0EDH D0)

IK1 (0EDH D1)

IMEL (0ECH D0)

* There is an interrupt mask register for each input port pin.

Writing to the interrupt mask registers should be done only in the

DI status (interrupt flag = 0). Otherwise it causes malfunction.

Specific masks and

factor flags for inter-

rupt

Table 4.12.2

Interrupt mask registers and

interrupt factor flags

Note

I-104 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Interrupt and HALT)

When an interrupt request is input to the CPU, the CPU

begins interrupt processing. After the program being exe-

cuted is suspended, interrupt processing is executed in the

following order:

➀The address data (value of the program counter) of the

program step to be executed next is saved on the stack

(RAM).

➁The interrupt request causes the value of the interrupt

vector (page 1, 02H–0BH) to be loaded into the program

counter.

➂The program at the specified address is executed (execu-

tion of interrupt processing routine).

Table 4.12.3 shows the correspondence of interrupt vectors

and priorities.

The processing in steps 1 and 2, above, takes 12 cycles of the

CPU system clock.

Vector Priority Interrupt Request

10AH 1 Melody interrupt

108H 2 Input (K10) interrupt

106H 3 Input (K00–K03) interrupt

104H 4 Stopwatch timer interrupt

102H 5 Clock timer interrupt

When multiple interrupts occur simultaneously, the interrupt vec-

tors with higher priority will be executed.

Interrupt vectors and

priorities

Note

Table 4.12.3

Interrupt vectors

and priorities

Note

S1C62N81 TECHNICAL HARDWARE EPSON I-105

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Interrupt and HALT)

Tables 4.12.4 (a)–(c) shows the interrupt control bits and

their addresses.

Table 4.12.4 (a) Interrupt control bits (1)

Control of interrupt

Address Comment

D3 D2 D1 D0 Name SR 1 0

0E5H

0E6H

0E7H

KCP03 KCP02 KCP01 KCP00

0 0 0 KCP10

00 0EIMEL

R/W

KCP03

KCP02

KCP01

KCP00

Input comparison register (K03)

Input comparison register (K02)

Input comparison register (K01)

Input comparison register (K00)

KCP10 0

EIMEL 0 Enable Mask

Input comparison register (K10)

Falling

Rising

Interrupt mask register (melody)

Falling Rising

R/W

0E8H

EIK03 EIK02 EIK01 EIK00

R/W

EIK03

EIK02

EIK01

EIK00

Interrupt mask register (K03)

Interrupt mask register (K02)

Interrupt mask register (K01)

Interrupt mask register (K00)

Enable

Mask

I-106 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Interrupt and HALT)

Table 4.12.4 (b) Interrupt control bits (2)

Address Comment

D3 D2 D1 D0 Name SR 1 0

0E9H

0EAH

0EBH

0 0 0 EIK10

0 0 EISW1 EISW0

0 EIT2 EIT8 EIT32

EIK10 0

Interrupt mask register (K10)

EISW1

EISW0

EIT2

EIT8

EIT32

Enable

Mask

Interrupt mask register (stopwatch 1 Hz)

Interrupt mask register (stopwatch 10 Hz)

Enable Mask

Interrupt mask register (clock timer 2 Hz)

Interrupt mask register (clock timer 8 Hz)

Interrupt mask register (clock timer 32 Hz)

Enable

Mask

R/W

0ECH

0 0 0 IMEL

IMEL 0

Interrupt factor flag (melody)

Yes No

S1C62N81 TECHNICAL HARDWARE EPSON I-107

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Interrupt and HALT)

Table 4.12.4 (c) Interrupt control bits (3)

Address Comment

D3 D2 D1 D0 Name SR 1 0

0EDH

0EEH

0EFH

00IK1IK0

0 0 ISW1 ISW0

0 IT2 IT8 IT32

IK1

IK0

Interrupt factor flag (K10)

Interrupt factor flag (K00–K03)

ISW1

ISW0

IT2

IT8

IT32

Yes

Interrupt factor flag (stopwatch 1 Hz)

Interrupt factor flag (stopwatch 10 Hz)

Yes

Interrupt factor flag (clock timer 2 Hz)

Interrupt factor flag (clock timer 8 Hz)

Interrupt factor flag (clock timer 32 Hz)

Yes

I-108 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Interrupt and HALT)

Interrupt mask registers (0EBH D0–D2)

Interrupt factor flags (0EFH D0–D2)

See 4.7, "Clock Timer".

Interrupt mask registers (0EAH D0–D1)

Interrupt factor flags (0EEH D0–D1)

See 4.8, "Stopwatch Timer".

Input comparison registers (0E5H)

Interrupt mask registers (0E8H)

Interrupt factor flag (0EDH D0)

See 4.3, "Input Ports".

Input comparison register (0E6H D0)

Interrupt mask register (0E9H D0)

Interrupt factor flag (0EDH D1)

See 4.3, "Input Ports".

Interrupt mask register (0E7H D0)

Interrupt factor flag (0ECH D0)

See 4.11, "Melody Generator".

EIT32, EIT8, EIT2

IT32, IT8, IT2

EISW0, EISW1

ISW0, ISW1

KCP00–KCP03

EIK00–EIK03

IK0

KCP10

EIK10

IK1

EIMEL

IMEL

S1C62N81 TECHNICAL HARDWARE EPSON I-109

CHAPTER 5: BASIC EXTERNAL WIRING DIAGRAM

BASIC EXTERNAL WIRING DIA-

GRAM

(1) Piezo Buzzer Single Terminal Driving

CHAPTER 5

OSC1

OSC2

RESET

TEST

MTEST

Vss

X'tal

S1 1.5V

3.0V

Piezo

Buzzer

R12

K00

K03

K10

P00

P03

CMPP

CMPM

R00

R03

R10

R11

I/O

SEG0

SEG25

COM0

COM3

LCD

PANEL

S1C62N81/62L81

Coil

X'tal

C1–C6

Crystal oscillator

Trimmer capacitor

Capacitor

32.768kHz CI(MAX)=35k

5–25pF

0.1 F

3.3 F

Ω

I-110 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 5: BASIC EXTERNAL WIRING DIAGRAM

(2) Piezo Buzzer Direct Driving

OSC1

OSC2

RESET

TEST

MTEST

Vss

X'tal

S1 1.5V

3.0V

Piezo

Buzzer

R12

K00

K03

K10

P00

P03

CMPP

CMPM

R00

R03

R10

R11

I/O

SEG0

SEG25

COM0

COM3

LCD

PANEL

S1C62N81/62L81

R1 R2

X'tal

C1–C6

R1, R2

Crystal oscillator

Trimmer capacitor

Capacitor

Protection resistance

32.768kHz CI(MAX)=35k

5–25pF

0.1 F

3.3 F

100

Ω

S1C62N81 TECHNICAL HARDWARE EPSON I-111

CHAPTER 5: BASIC EXTERNAL WIRING DIAGRAM

(3) Envelope Driving

OSC1

OSC2

RESET

TEST

MTEST

Vss

X'tal

S1 1.5V

3.0V

Piezo

Buzzer

R12

K00

K03

K10

P00

P03

CMPP

CMPM

R00

R03

R10

R11

I/O

SEG0

SEG25

COM0

COM3

LCD

PANEL

S1C62N81/62L81

Coil

X'tal

C1–C6

Crystal oscillator

Trimmer capacitor

Capacitor

Resistor

32.768kHz CI(MAX)=35k

5–25pF

0.1 F

1 F–10 F

3.3 F

1k or more

Ω

µµ

Ω

I-112 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 6: ELECTRICAL CHARACTERISTICS

CHAPTER 6 ELECTRICAL CHARACTERISTICS

6.1 Absolute Maximum Rating

S1C62N81/62A81

Power voltage

Input voltage (1)

Input voltage (2)

Permissible total output current *1

Operating temperature

Storage temperature

Soldering temperature / Time

Allowable dissipation *2

Item Symbol

Vss

Ivss

Topr

Tstg

Tsol

Rated Value

-5.0 to 0.5

Vss-0.3 to 0.5

-20 to 70

-65 to 150

260°C, 10sec (lead section)

250

Unit

°C

–

(V =0V)DD

IOSC

*1 The permissible total output current is the sum total of

the current (average current) that simultaneously flows

from the output pins (or is drawn in).

*2 In case of 64-pin plastic package.

S1C62L81/62B81

Power voltage

Input voltage (1)

Input voltage (2)

Permissible total output current *1

Operating temperature

Storage temperature

Soldering temperature / Time

Allowable dissipation *2

Item Symbol

Vss

Ivss

Topr

Tstg

Tsol

Rated Value

-5.0 to 0.5

Vss-0.3 to 0.5

-20 to 70

-65 to 150

260°C, 10sec (lead section)

250

Unit

°C

–

(V =0V)DD

IOSC

*1 The permissible total output current is the sum total of

the current (average current) that simultaneously flows

from the output pins (or is drawn in).

*2 In case of 64-pin plastic package.

S1C62N81 TECHNICAL HARDWARE EPSON I-113

CHAPTER 6: ELECTRICAL CHARACTERISTICS

6.2 Recommended Operating Conditions

S1C62N81/62A81

S1C62L81/62B81

*1 When switching to the heavy load protection mode.

The BLD circuit and analog voltage comparator are

turned OFF.

(For details, refer to Section 4.9).

*2 The voltage which can be displayed on the LCD panel will

differ according to the characteristics of the LCD panel.

Item

Power voltage

Oscillation frequency

Symbol

Vss

fosc

Condition

V =0V

Min

-3.5 Typ

-3.0

32.768

Unit

kHz

Max

-1.8

(Ta=-20 to 70°C)

Item

Power voltage

Oscillation frequency

Symbol

Vss

fosc

Condition

V =0V

V =0V,

With software correspondence

V =0V, When analog

comparator is used

Min

-3.5

Typ

-1.5

32.768

Unit

kHz

Max

-1.1

-0.9

-1.3

(Ta=-20 to 70°C)

I-114 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 6: ELECTRICAL CHARACTERISTICS

6.3 DC Characteristics

S1C62N81/62A81

Unless otherwise specified

VDD=0 V, VSS=-3.0 V, fosc=32.768 kHz, Ta=25°C, VS1,

VL1, VL2 and VL3 are internal voltages, and

C1=C2=C3=C4=C5=C6=0.1 µF

Item

High level input voltage (1)

High level input voltage (2)

Low level input voltage (1)

Low level input voltage (2)

High level input current (1)

High level input current (2)

High level input current (3)

Low level input current

Symbol

Condition

V =0V

Without pull down resistor

V =0V

With pull down resistor

V =0V

With pull down resistor

V =Vss

V =0.1•Vss

V =0.9•Vss

V =-0.05V

V =V +0.05V

Min

0.2•Vss

0.10•Vss

Vss

-0.5

3.0

4.5

300

Typ Unit

µA

Max

0.8•Vss

0.90•Vss

0.5

100

-1.0

-2.0

-3

-300

High level output current (1)

High level output current (2)

High level output current (3)

Low level output current (1)

Low level output current (2)

Low level output current (3)

Common output current

V =-0.05V

V =V +0.05V

V =0.1•Vss

V =0.9•Vss

K00–K03, K10, P00–P03

CMPP, CMPM

K00–K03, K10

P00–P03

RESET, TEST, MTEST

K00–K03, K10

P00–P03

CMPP, CMPM

RESET, TEST, MTEST

R11

R00–R03, R10

P00–P03

MO, R12

R11

R00–R03, R10

P00–P03

MO, R12

COM0–COM3

SEG0–SEG25

IH1

IH2

IL1

IL2

IH1

IH2

IH3

OH1

OH2

OH3

OL1

OL2

OL3

OH4

OL4

OH5

OL5

OH6

OL6

OH1

OH2

OH3

OL1

OL2

OL3

OH4

OL4

OH5

OL5

OH6

OL6

Segment output current

(during LCD output)

Segment output current

(during DC output)

K00–K03, K10, P00–P03, MTEST

RESET, TEST

K00–K03, K10, P00–P03, MTEST

RESET, TEST

S1C62N81 TECHNICAL HARDWARE EPSON I-115

CHAPTER 6: ELECTRICAL CHARACTERISTICS

S1C62L81/62B81

Unless otherwise specified

VDD=0 V, VSS=-1.5 V, fosc=32.768 kHz, Ta=25°C, VS1,

VL1, VL2 and VL3 are internal voltages, and

C1=C2=C3=C4=C5=C6=0.1 µF

Item

High level input voltage (1)

High level input voltage (2)

Low level input voltage (1)

Low level input voltage (2)

High level input current (1)

High level input current (2)

High level input current (3)

Low level input current

Symbol

Condition

V =0V

Without pull down resistor

V =0V

With pull down resistor

V =0V

With pull down resistor

V =Vss

V =0.1•Vss

When envelope is used

V =0.9•Vss

V =-0.05V

V =V +0.05V

Min

0.2•Vss

0.10•Vss

Vss

2.0

9.0

-0.5

1300

700

1.5

130

Typ Unit

µA

Max

0.8•Vss

0.90•Vss

0.5

-450

-200

-0.8

-0.4

-3

-100

High level output current (1)

High level output current (2)

High level output current (3)

High level output current (4)

Low level output current (1)

Low level output current (2)

Low level output current (3)

Common output current

V =-0.05V

V =V +0.05V

V =0.1•Vss

V =0.9•Vss

K00–K03, K10, P00–P03

CMPP, CMPM

K00–K03, K10

P00–P03

RESET, TEST, MTEST

K00–K03, K10

P00–P03

CMPP, CMPM

RESET, TEST, MTEST

R11

R00–R03, R10

P00–P03

MO, R12

R11

R00–R03, R10

P00–P03

MO, R12

COM0–COM3

SEG0–SEG25

IH1

IH2

IL1

IL2

IH1

IH2

IH3

OH1

OH2

OH3

OH4

OL1

OL2

OL3

OH5

OL5

OH6

OL6

OH7

OL7

OH1

OH2

OH3

OH4

OL1

OL2

OL3

OH5

OL5

OH6

OL6

OH7

OL7

Segment output current

(during LCD output)

Segment output current

(during DC output)

K00–K03, K10, P00–P03, MTEST

RESET, TEST

K00–K03, K10, P00–P03, MTEST

RESET, TEST

I-116 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 6: ELECTRICAL CHARACTERISTICS

6.4 Analog Circuit Characteristics and Power

Current Consumption

S1C62N81 (Normal Operating Mode)

Unless otherwise specified

VDD=0 V, VSS=-3.0 V, fosc=32.768 kHz, Ta=25°C,

CG=25 pF, VS1, VL1, VL2 and VL3 are internal voltages,

and C1=C2=C3=C4=C5=C6=0.1 µF

Item

Internal voltage

BLD voltage

BLD circuit response time

Analog comparator

input voltage

Analog comparator

offset voltage

Analog comparator

response time

Power current

consumption

Symbol

Condition

Connect 1M load resistor between V and V

(without panel load)

Connect 1M load resistor between V and V

(without panel load)

Connect 1M load resistor between V and V

(without panel load)

Non-inverted input (CMPP)

Inverted input (CMPM)

Min

-1.15

2•V

-0.1

3•V

-0.1

-2.55

Vss+0.3

Typ

-1.05

-2.40

1.0

2.5

Unit

µs

µA

Max

-0.95

2•V

0.9

3•V

0.9

-2.25

100

V -0.9

2.5

5.0

During HALT

During execution Without panel load

BLD

CMP

Ω

V =-1.5V

V =V ±15mV

IM IP

*1 The BLD circuit and analog voltage comparator are

turned OFF.

S1C62N81 TECHNICAL HARDWARE EPSON I-117

CHAPTER 6: ELECTRICAL CHARACTERISTICS

Item

Internal voltage

BLD voltage

BLD circuit response time

Analog comparator

input voltage

Analog comparator

offset voltage

Analog comparator

response time

Power current

consumption

Symbol

Condition

Connect 1M load resistor between V and V

(without panel load)

Connect 1M load resistor between V and V

(without panel load)

Connect 1M load resistor between V and V

(without panel load)

Non-inverted input (CMPP)

Inverted input (CMPM)

Min

-1.15

2•V

-0.1

3•V

-0.1

-2.55

Vss+0.3

Typ

-1.05

-2.40

2.0

5.5

Unit

µs

µA

Max

-0.95

2•V

0.85

3•V

0.85

-2.25

100

V -0.9

5.5

10.0

During HALT

During execution Without panel load

BLD

CMP

Ω

V =-1.5V

V =V ±15mV

IM IP

S1C62N81 (Heavy Load Protection Mode)

Unless otherwise specified

VDD=0 V, VSS=-3.0 V, fosc=32.768 kHz, Ta=25°C,

CG=25 pF VS1, VL1, VL2 and VL3 are internal voltages, and

C1=C2=C3=C4=C5=C6=0.1 µF

*1 The BLD circuit and analog voltage comparator are

turned OFF.

I-118 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 6: ELECTRICAL CHARACTERISTICS

S1C62L81 (Normal Operating Mode)

Unless otherwise specified

VDD=0 V, VSS=-1.5 V, fosc=32.768 kHz, Ta=25°C, CG=25

pF VS1, VL1, VL2 and VL3 are internal voltages, and

C1=C2=C3=C4=C5=C6=0.1 µF

Item

Internal voltage

BLD voltage

BLD circuit response time

Analog comparator

input voltage

Analog comparator

offset voltage

Analog comparator

response time

Power current

consumption

Symbol

Condition

Connect 1M load resistor between V and V

(without panel load)

Connect 1M load resistor between V and V

(without panel load)

Connect 1M load resistor between V and V

(without panel load)

Non-inverted input (CMPP)

Inverted input (CMPM)

Min

-1.15

2•V

-0.1

3•V

-0.1

-1.30

Vss+0.3

Typ

-1.05

-1.20

1.0

2.5

Unit

µs

µA

Max

-0.95

2•V

0.9

3•V

0.9

-1.10

100

V -0.9

2.5

5.0

During HALT

During execution Without panel load

BLD

CMP

Ω

V =-1.1V

V =V ±30mV

IM IP

*1 The BLD circuit and analog voltage comparator are

turned OFF.

S1C62N81 TECHNICAL HARDWARE EPSON I-119

CHAPTER 6: ELECTRICAL CHARACTERISTICS

Item

Internal voltage

BLD voltage

BLD circuit response time

Analog comparator

input voltage

Analog comparator

offset voltage

Analog comparator

response time

Power current

consumption

Symbol

Condition

Connect 1M load resistor between V and V

(without panel load)

Connect 1M load resistor between V and V

(without panel load)

Connect 1M load resistor between V and V

(without panel load)

Non-inverted input (CMPP)

Inverted input (CMPM)

Min

-1.15

2•V

-0.1

3•V

-0.1

-1.30

Vss+0.3

Typ

-1.05

-1.20

2.0

5.5

Unit

µs

µA

Max

-0.95

2•V

0.85

3•V

0.85

-1.10

100

V -0.9

5.5

10.0

During HALT

During execution Without panel load

BLD

CMP

Ω

V =-1.1V

V =V ±30mV

IM IP

S1C62L81 (Heavy Load Protection Mode)

Unless otherwise specified

VDD=0 V, VSS=-1.5 V, fosc=32.768 kHz, Ta=25°C, CG=25

pF VS1, VL1, VL2 and VL3 are internal voltages, and

C1=C2=C3=C4=C5=C6=0.1 µF

*1 The BLD circuit and analog voltage comparator are

turned OFF.

I-120 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 6: ELECTRICAL CHARACTERISTICS

S1C62A81 (Normal Operating Mode)

Unless otherwise specified

VDD=0 V, VSS=-3.0 V, fosc=32.768 kHz, Ta=25°C,

CG=25pF VS1, VL1, VL2 and VL3 are internal voltages, and

C1=C2=C3=C4=C5=C6=0.1 µF

*1 The BLD circuit and analog voltage comparator are

turned OFF.

Item

Internal voltage

BLD voltage

BLD circuit response time

Analog comparator

input voltage

Analog comparator

offset voltage

Analog comparator

response time

Power current

consumption

Symbol

Condition

Connect 1M load resistor between V and V

(without panel load)

Connect 1M load resistor between V and V

(without panel load)

Connect 1M load resistor between V and V

(without panel load)

Non-inverted input (CMPP)

Inverted input (CMPM)

Min

-1.15

2•V

-0.1

3•V

-0.1

-2.55

Vss+0.3

Typ

-1.05

-2.40

5.5

7.2

Unit

µs

µA

Max

-0.95

2•V

0.9

3•V

0.9

-2.25

100

V -0.9

10.0

12.0

During HALT

During execution Without panel load

BLD

CMP

Ω

V =-1.5V

V =V ±15mV

IM IP

S1C62N81 TECHNICAL HARDWARE EPSON I-121

CHAPTER 6: ELECTRICAL CHARACTERISTICS

S1C62A81 (Heavy Load Protection Mode)

Unless otherwise specified

VDD=0 V, VSS=-3.0 V, fosc=32.768 kHz, Ta=25°C,

CG=25pF VS1, VL1, VL2 and VL3 are internal voltages, and

C1=C2=C3=C4=C5=C6=0.1 µF

*1 The BLD circuit and analog voltage comparator are

turned OFF.

Item

Internal voltage

BLD voltage

BLD circuit response time

Analog comparator

input voltage

Analog comparator

offset voltage

Analog comparator

response time

Power current

consumption

Symbol

Condition

Connect 1M load resistor between V and V

(without panel load)

Connect 1M load resistor between V and V

(without panel load)

Connect 1M load resistor between V and V

(without panel load)

Non-inverted input (CMPP)

Inverted input (CMPM)

Min

-1.15

2•V

-0.1

3•V

-0.1

-2.55

Vss+0.3

Typ

-1.05

-2.40

11.0

15.0

Unit

µs

µA

Max

-0.95

2•V

0.85

3•V

0.85

-2.25

100

V -0.9

20.0

25.0

During HALT

During execution Without panel load

BLD

CMP

V =-1.5V

V =V ±15mV

Ω

IM IP

I-122 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 6: ELECTRICAL CHARACTERISTICS

S1C62B81 (Normal Operating Mode)

Unless otherwise specified

VDD=0 V, VSS=-1.5 V, fosc=32.768 kHz, Ta=25°C,

CG=25pF VS1, VL1, VL2 and VL3 are internal voltages, and

C1=C2=C3=C4=C5=C6=0.1 µF

*1 The BLD circuit and analog voltage comparator are

turned OFF.

Item

Internal voltage

BLD voltage

BLD circuit response time

Analog comparator

input voltage

Analog comparator

offset voltage

Analog comparator

response time

Power current

consumption

Symbol

Condition

Connect 1M load resistor between V and V

(without panel load)

Connect 1M load resistor between V and V

(without panel load)

Connect 1M load resistor between V and V

(without panel load)

Non-inverted input (CMPP)

Inverted input (CMPM)

Min

-1.15

2•V

-0.1

3•V

-0.1

-1.30

Vss+0.3

Typ

-1.05

-1.20

5.5

7.2

Unit

µs

µA

Max

-0.95

2•V

0.9

3•V

0.9

-1.10

100

V -0.9

10.0

12.0

During HALT

During execution Without panel load

BLD

CMP

Ω

V =-1.1V

V =V ±30mV

IM IP

S1C62N81 TECHNICAL HARDWARE EPSON I-123

CHAPTER 6: ELECTRICAL CHARACTERISTICS

S1C62B81 (Heavy Load Protection Mode)

Unless otherwise specified

VDD=0 V, VSS=-1.5 V, fosc=32.768 kHz, Ta=25°C, VS1,

VL1, VL2 and VL3 are internal voltages, and

C1=C2=C3=C4=C5=C6=0.1 µF

*1 The BLD circuit and analog voltage comparator are

turned OFF.

Item

Internal voltage

BLD voltage

BLD circuit response time

Analog comparator

input voltage

Analog comparator

offset voltage

Analog comparator

response time

Power current

consumption

Symbol

Condition

Connect 1M load resistor between V and V

(without panel load)

Connect 1M load resistor between V and V

(without panel load)

Connect 1M load resistor between V and V

(without panel load)

Non-inverted input (CMPP)

Inverted input (CMPM)

Min

-1.15

2•V

-0.1

3•V

-0.1

-1.30

Vss+0.3

Typ

-1.05

-1.20

11.0

15.0

Unit

µs

µA

Max

-0.95

2•V

0.85

3•V

0.85

-1.10

100

V -0.9

20.0

25.0

During HALT

During execution Without panel load

BLD

CMP

Ω

V =-1.1V

V =V ±30mV

IM IP

I-124 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 6: ELECTRICAL CHARACTERISTICS

Item

Oscillation start

voltage

Oscillation stop

voltage

Built-in capacity (drain)

Frequency voltage deviation

Frequency IC deviation

Frequency adjustment range

Higher harmonic oscillation

start voltage

Allowable leak resistor

Symbol

Vsta

(Vss)

Vstp

(Vss)

f/V

f/I

f/C

hho

(Vss)

leak

Condition

tsta 3 sec

tstp 10 sec

Including the parasitic capacity inside the IC

Vss=-1.1 to -3.5 V (-0.9)

C =5–25pF

Between OSC1 and V and Vss

Min

-1.1

(-0.9)

-10

200

Typ

Unit

ppm

Max

-3.5

Ω

≤

Item

Oscillation start

voltage

Oscillation stop

voltage

Built-in capacity (drain)

Frequency voltage deviation

Frequency IC deviation

Frequency adjustment range

Higher harmonic oscillation

start voltage

Allowable leak resistor

Symbol

Vsta

(Vss)

Vstp

(Vss)

f/V

f/I

f/C

Vhho

(Vss)

Rleak

Condition

sta 3 sec

stp 10 sec

Including the parasitic capacity inside the IC

Vss=-1.8 to -3.5 V

C =5–25pF

Between OSC1 and V and Vss

Min

-1.8

-10

200

Typ

Unit

ppm

Max

-3.5

Ω

≤

6.5 Oscillation Characteristics

Oscillation characteristics will vary according to different

conditions. Use the following characteristics are as refer-

ence values.

S1C62N81

Unless otherwise specified,

VDD=0 V, VSS=-3.0 V, Crystal: Q13MC146, CG=25 pF,

CD=built-in, Ta=25°C

S1C62L81

Unless otherwise specified,

VDD=0 V, VSS=-1.5 V, Crystal: Q13MC146, CG=25 pF,

CD=built-in, Ta=25°C

*1 Items enclosed in parentheses ( ) are those used when

operating at heavy load protection mode.

S1C62N81 TECHNICAL HARDWARE EPSON I-125

CHAPTER 6: ELECTRICAL CHARACTERISTICS

S1C62B81

Unless otherwise specified,

VDD=0 V, VSS=-1.5 V, RCR=850 kΩ, Ta=25°C

Item

Oscillation frequency dispersion

Oscillation start voltage

Oscillation start time

Oscillation stop voltage

Symbol

fosc

Vsta

sta

Vstp

Condition

Vss=-0.9 to -3.5V

Min

-20

-0.9

Typ

32.768 kHz

Unit

Max

S1C62A81

Unless otherwise specified,

VDD=0 V, VSS=-3.0 V, RCR=850 kΩ, Ta=25°C

Item

Oscillation frequency dispersion

Oscillation start voltage

Oscillation start time

Oscillation stop voltage

Symbol

fosc

Vsta

sta

Vstp

Condition

Vss=-1.8 to -3.5V

Min

-20

-1.8

Typ

32.768 kHz

Unit

Max

I-126 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 7: PACKAGE

CHAPTER 7 PACKAGE

7.1 Plastic Package (1)

QFP6-64pin

Index

116

48 33

14.0

16.8

±0.2

±0.4

14.0

16.8

±0.2

±0.4

0.35 ±0.15

0.8 ±0.15

0.15 ±0.05

2.7 ±0.1

±0.3

1.4

0.6

0~12°

S1C62N81 TECHNICAL HARDWARE EPSON I-127

CHAPTER 7: PACKAGE

7.2 Plastic Package (2)

QFP13-64pin

Index

116

48 33

10.0

12.0

±0.1

±0.4

10.0

12.0

±0.1

±0.4

0.18 ±0.1

0.5 ±0.1

0.127

±0.05

1.4

±0.1

±0.2

1.0

0.5

0~12°

I-128 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 7: PACKAGE

7.3

12Pin No. Index Mark 3132

64 63 3433

81.28

78.78

23.11

2.54

SEG4

SEG5

SEG6

SEG7

SEG8

SEG9

SEG10

SEG11

TEST

SEG12

SEG13

SEG14

SEG15

SEG16

SEG17

SEG18

SEG19

SEG20

SEG21

SEG22

SEG23

SEG24

P00

P01

P02

P03

CMPM

CMPP

MTEST

RESET

K00

SEG3

SEG2

SEG1

SEG0

SEG25

COM3

COM2

COM1

COM0

VL1

VL2

VL3

OSC1

OSC2

VSS

VDD

VS1

R03

R02

R01

R00

R12

R11

R10

K10

K03

K02

K01

Ceramic Package for Test Sample

S1C62N81 TECHNICAL HARDWARE EPSON I-129

CHAPTER 8: PAD LAYOUT

CHAPTER 8 PAD LAYOUT

8.1 Diagram of Pad Layout

171615141312111098765 4321

32 33 34 35 36 37 38 39 40 41 42 46 47 4843 44 45

Die No.

Chip size: 3.84 mm × 3.84 mm

Chip thickness: 400 µm

Pad opening: 95 µm

I-130 EPSON S1C62N81 TECHNICAL HARDWARE

CHAPTER 8: PAD LAYOUT

8.2 S1C62N81 List of Pad Names

PAD Name

COM0

COM1

COM2

COM3

SEG25

SEG0

SEG1

SEG2

SEG3

SEG4

SEG5

SEG6

SEG7

SEG8

SEG9

SEG10

SEG11

TEST

SEG12

SEG13

SEG14

PAD Name

SEG15

SEG16

SEG17

SEG18

SEG19

SEG20

SEG21

SEG22

SEG23

SEG24

P00

P01

P02

P03

CMPM

CMPP

MTEST

RESET

K00

K01

K02

PAD Name

K03

K10

R10

R11

R12

R00

R01

R02

R03

OSC2

OSC1

S1C62N81 TECHNICAL HARDWARE EPSON I-131

CHAPTER 8: PAD LAYOUT

8.3 Pad Coordinates

PAD No

1722.0

1560.4

1400.4

1238.8

616.0

456.0

296.0

136.0

-24.0

-184.0

-344.0

-504.0

-664.0

-824.0

-984.0

-1144.0

-1304.0

-1753.2

1753.2

1538.8

1317.2

1157.2

997.2

PAD No

-1753.2

-1714.0

-1554.0

-1393.2

-1233.2

-1025.6

-685.2

-524.8

-349.6

92.4

251.6

412.4

837.2

677.2

517.2

357.2

197.2

37.2

-122.8

-282.8

-442.8

-602.8

-1752.4

PAD No

571.6

732.4

914.0

1090.0

1249.6

1679.2

1753.2

-1752.4

-856.0

-696.0

-536.0

-376.0

-210.8

-50.8

109.2

269.2

430.8

613.2

773.2

937.2

1097.2

1261.2

1421.2

Software

S1C62N81

II.

Technical Software

Software

S1C62N81 TECHNICAL SOFTWARE EPSON II-i

CONTENTS

CHAPTER 1 CONFIGURATION ........................................................... II-1

1.1 S1C62N81 Block Diagram ............................................. II-1

1.2 ROM Map ....................................................................... II-2

1.3 Interrupt Vectors............................................................. II-3

1.4 Data Memory Map.......................................................... II-4

CHAPTER 2 INITIAL RESET .................................................................. II-12

2.1 Internal Register Status on Initial Reset ........................ II-12

2.2 Initialize Program Example............................................ II-14

CHAPTER 3 PERIPHERAL CIRCUITS.................................................... II-16

3.1 Input Ports ..................................................................... II-16

Input port memory map .......................................... II-16

Control of the input port ......................................... II-18

Examples of input port control program .................. II-18

3.2 Output Ports .................................................................. II-20

Output port memory map........................................ II-20

Control of the output port ....................................... II-21

Examples of output port control program ................ II-21

3.3 Special Use Output Ports .............................................. II-23

Special use output port memory map ...................... II-23

Control of the special use output port ..................... II-24

Example of special use output port control program .. II-25

3.4 I/O Ports ........................................................................ II-26

I/O port memory map ............................................. II-26

Control of the I/O port ............................................ II-27

Examples of I/O port control program ..................... II-28

II-ii EPSON S1C62N81 TECHNICAL SOFTWARE

CONTENTS

3.5 LCD Driver..................................................................... II-31

LCD driver memory map ......................................... II-31

Control of the LCD driver ........................................ II-32

Examples of LCD driver control program ................. II-34

3.6 Timer ............................................................................. II-36

Timer memory map ................................................. II-36

Control of the timer................................................. II-37

Examples of timer control program.......................... II-38

3.7 Stopwatch Timer ........................................................... II-40

Stopwatch timer memory map................................. II-40

Control of the stopwatch timer ................................ II-41

Examples of stopwatch timer control program ......... II-42

3.8 Battery Voltage Low Detection (BLD) Circuit

and Heavy Load Protection Function ............................ II-44

BLD circuit and heavy load protection

function memory map ............................................. II-44

Control of the BLD circuit ....................................... II-45

Example of BLD circuit control program.................. II-45

Heavy load protection function ................................ II-46

Examples of heavy load protection

function control program......................................... II-48

3.9 Analog Comparator ....................................................... II-51

Analog comparator memory map ............................. II-51

Example of CMP control program ............................ II-52

3.10 Melody Generator.......................................................... II-53

Melody generator memory map................................ II-53

Address setting (Addresses 0F0H and 0F1H) ........... II-54

Play mode control.................................................... II-54

Melody interrupt ..................................................... II-61

Melody ROM ........................................................... II-61

Scale ROM .............................................................. II-63

Examples of melody control program....................... II-64

Software

S1C62N81 TECHNICAL SOFTWARE EPSON II-iii

CONTENTS

3.11 Interrupt and Halt........................................................... II-67

Interrupt memory map ............................................ II-67

Control of interrupts and halt ................................. II-70

Examples of interrupt and halt control program ...... II-81

CHAPTER 4 SUMMARY OF PROGRAMMING POINTS....................... II-85

APPENDIX A Table of Instructions ...................................................... II-89

B The S1C62N81 I/O Memory Map.................................. II-94

C Table of the ICE Commands ......................................... II-96

D Cross-assembler Pseudo Instruction List...................... II-98

E The Format of Melody Source File ................................ II-99

Source File Name .................................................... II-99

Statement (line)....................................................... II-99

Attack field ........................................................ II-100

Note field ........................................................... II-100

Scale field .......................................................... II-100

End bit field....................................................... II-100

Comment field ................................................... II-100

F Dividing Table............................................................... II-101

G RAM Map ..................................................................... II-103

S1C62N81 TECHNICAL SOFTWARE EPSON II-1

CHAPTER 1: CONFIGURATION

CHAPTER 1

1.1

CONFIGURATION

S1C62N81 Block Diagram

Fig. 1.1.1

S1C62N81 block diagram

Melody

Comparator

& BLD

Power

Controller

LCD

Driver

RAM

96x4 Interrupt

Generator

I Port

Test Port

I/O Port

O Port

Timer

Stop

Watch

Core CPU S1C6200

ROM

1,024x12 OSC System

Reset

Control

RESE

OSC1

COM0

COM3

SEG0

SEG25

K00–K03

K10

TEST

MTEST

P00–P03

R00–R03

R10, R11

OSC2

CMPP

CMPM

R12

II-2 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 1: CONFIGURATION

ROM Map

The S1C62N81 has a built-in mask ROM with a capacity of

1,024 steps × 12 bits for program storage. The configura-

tion of the ROM is shown in Figure 1.2.1.

00H step

02H step

0BH step

0CH step

FFH step

12 bits

Program start address

Interrupt vector area

Bank 0

Program area

0 page

1 page

2 page

3 page

01H step

1.2

Fig. 1.2.1

Configuration of built-in ROM

S1C62N81 TECHNICAL SOFTWARE EPSON II-3

CHAPTER 1: CONFIGURATION

1.3 Interrupt Vectors

When an interrupt request is received by the CPU, the CPU

initiates the following interrupt processing after completing

the instruction being executed.

(1)The address of the next instruction to be executed (the

value of the program counter) is saved on the stack

(RAM).

(2)The interrupt vector address corresponding to the inter-

rupt request is loaded into the program counter.

(3)The branch instruction written in the vector is executed

to branch to the software interrupt processing routine.

Steps 1 and 2 require 12 cycles of the CPU system clock.

The correspondence between interrupt requests and vectors

are shown in Table 1.3.1.

When multiple interrupts occur simultaneously, they are

executed in order of priority.

Note

Table 1.3.1

Interrupt requests and vectors

Vector Priority Interrupt Request

10AH

108H

106H

104H

102H

Melody interrupt

Input (K10) interrupt

Input (K00–K03) interrupt

Stopwatch timer interrupt

Clock timer interrupt

II-4 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 1: CONFIGURATION

Data Memory Map

The S1C62N81 built-in RAM has 96 words of data memory,

32 words of display memory for the LCD, and I/O memory

for controlling the peripheral circuit. When writing pro-

grams, note the following:

(1)Since the stack area is in the data memory area, take

care not to overwrite the stack with data. Subroutine

calls or interrupts use 3 words on the stack.

(2)Data memory addresses 000H–00FH are memory register

areas that are addressed with register pointer RP.

Address

Page High

Low 0123456789ABCDEF

M0 M1 M2 M3 M4 M5 M6 M7 M8 M9 MA MB MC MD ME MF

RAM (96 words x 4 bits)

R/W

Unused area

I/O memory

Display memory

Unused area

Fig. 1.4.1

Data memory map

1.4

Memory is not mounted in unused area within the memory map

and in memory area not indicated in this chapter. For this reason,

normal operation cannot be assured for programs that have been

prepared with access to these areas.

Note

S1C62N81 TECHNICAL SOFTWARE EPSON II-5

CHAPTER 1: CONFIGURATION

Table 1.4.1 (a) I/O memory map (0E0H–0E3H)

*1 Initial value following initial reset

*2 Not set in the circuit

*3 Undefined

*4 Reset (0) immediately after being read

*5 Always 0 when being read

*6 Refer to main manual

Address Comment

D3 D2 D1 D0 Name SR *1 10

0E0H

0E1H

0E2H

0E3H

K03 K02 K01 K00

0 0 0 K10

SWL3 SWL2 SWL1 SWL0

SWH3 SWH2 SWH1 SWH0

K03

K02

K01

K00

–

K10 –

Input port (K10)

SWL3

SWL2

SWL1

SWL0

SWH3

SWH2

SWH1

SWH0

MSB

Stopwatch timer

1/100 sec (BCD)

LSB

Input port (K00–K03)

High

Low

High Low

MSB

Stopwatch timer

1/10 sec (BCD)

LSB

II-6 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 1: CONFIGURATION

Table 1.4.1 (b) I/O memory map (0E4H–0E7H)

Address Comment

D3 D2 D1 D0 Name SR *1 10

0E4H

0E5H

0E6H

0E7H

TM3 TM2 TM1 TM0

KCP03 KCP02 KCP01 KCP00

0 0 0 KCP10

0 0 0 EIMEL

R/W

TM3

TM2

TM1

TM0

–

KCP03

KCP02

KCP01

KCP00

Input comparison register (K03)

Input comparison register (K02)

Input comparison register (K01)

Input comparison register (K00)

KCP10 0

EIMEL 0 Enable Mask

Input comparison register (K10)

Timer data (clock timer 2 Hz)

Timer data (clock timer 4 Hz)

Timer data (clock timer 8 Hz)

Timer data (clock timer 16 Hz)

High

Low

Falling

Rising

Interrupt mask register (melody)

Falling Rising

R/W

*1 Initial value following initial reset

*2 Not set in the circuit

*3 Undefined

*4 Reset (0) immediately after being read

*5 Always 0 when being read

*6 Refer to main manual

S1C62N81 TECHNICAL SOFTWARE EPSON II-7

CHAPTER 1: CONFIGURATION

Table 1.4.1 (c) I/O memory map (0E8H–0EBH)

Address Comment

D3 D2 D1 D0 Name SR *1 10

0E8H

0E9H

0EAH

0EBH

EIK03 EIK02 EIK01 EIK00

0 0 0 EIK10

0 0 EISW1 EISW0

0 EIT2 EIT8 EIT32

R/W

EIK03

EIK02

EIK01

EIK00

EIK10 0

Interrupt mask register (K10)

EISW1

EISW0

EIT2

EIT8

EIT32

Enable

Mask

Interrupt mask register (stopwatch 1 Hz)

Interrupt mask register (stopwatch 10 Hz)

Interrupt mask register (K03)

Interrupt mask register (K02)

Interrupt mask register (K01)

Interrupt mask register (K00)

Enable

Mask

Enable Mask

Interrupt mask register (clock timer 2 Hz)

Interrupt mask register (clock timer 8 Hz)

Interrupt mask register (clock timer 32 Hz)

Enable

Mask

R/W

*1 Initial value following initial reset

*2 Not set in the circuit

*3 Undefined

*4 Reset (0) immediately after being read

*5 Always 0 when being read

*6 Refer to main manual

II-8 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 1: CONFIGURATION

Table 1.4.1 (d) I/O memory map (0ECH–0EFH)

*1 Initial value following initial reset

*2 Not set in the circuit

*3 Undefined

*4 Reset (0) immediately after being read

*5 Always 0 when being read

*6 Refer to main manual

Address Comment

D3 D2 D1 D0 Name SR *1 10

0ECH

0EDH

0EEH

0EFH

0 0 0 IMEL

00IK1IK0

0 0 ISW1 ISW0

0 IT2 IT8 IT32

IMEL 0

IK1

IK0

Interrupt factor flag (K10)

Interrupt factor flag (K00–K03)

ISW1

ISW0

IT2

IT8

IT32

Yes

Interrupt factor flag (stopwatch 1 Hz)

Interrupt factor flag (stopwatch 10 Hz)

Interrupt factor flag (melody)

Yes No

Yes

Interrupt factor flag (clock timer 2 Hz)

Interrupt factor flag (clock timer 8 Hz)

Interrupt factor flag (clock timer 32 Hz)

Yes

S1C62N81 TECHNICAL SOFTWARE EPSON II-9

CHAPTER 1: CONFIGURATION

Table 1.4.1 (e) I/O memory map (0F0H–0F3H)

Address Comment

D3 D2 D1 D0 Name SR *1 10

0F0H

0F1H

0F2H

0F3H

MAD3 MAD2 MAD1 MAD0

0 MAD6 MAD5 MAD4

CLKC1 CLKC0 TEMPC MELC

R03 R02 R01 R00

R/W

MAD3

MAD2

MAD1

MAD0

MAD6

MAD5

MAD4

Melody ROM address (AD6, MSB)

Melody ROM address (AD5)

Melody ROM address (AD4)

CLKC1

CLKC0

TEMPC

MELC

R03

R02

R01

R00

High

Low

CLKC1(0)&CLKC0(0) : melody speed 1

CLKC1(0)&CLKC0(1) : melody speed 8

CLKC1(1)&CLKC0(0) : melody speed 16

CLKC1(1)&CLKC0(1) : melody speed 32

Tempo change control

Melody control ON/OFF

Melody ROM address (AD3)

Melody ROM address (AD2)

Melody ROM address (AD1)

Melody ROM address (AD0, LSB)

High

Low

High

Low

Output port data (R00–R03)

High

Low

OFF

R/W

*1 Initial value following initial reset

*2 Not set in the circuit

*3 Undefined

*4 Reset (0) immediately after being read

*5 Always 0 when being read

*6 Refer to main manual

II-10 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 1: CONFIGURATION

Table 1.4.1 (f) I/O memory map (0F4H, 0F6H, 0F9H–0FAH)

*1 Initial value following initial reset

*2 Not set in the circuit

*3 Undefined

*4 Reset (0) immediately after being read

*5 Always 0 when being read

*6 Refer to main manual

Address Comment

D3 D2 D1 D0 Name SR *1 10

0F4H

0F6H

0F9H

0FAH

R12

ENV R11 R10

FOUT

P03 P02 P01 P00

0 TMRST SWRUN SWRST

HLMOD 0 BLDDT BLDON

R/W R12

ENV

R11

R10

FOUT

P03

P02

P01

P00

–

I/O port (P00–P03)

TMRST

SWRUN

SWRST

Reset

HLMOD

BLDDT

BLDON

0 ON OFF

Clock timer reset

Stopwatch timer RUN/STOP

Stopwatch timer reset

Output port data (R12)

Inverting melody output

Melody envelope control

Output port data (R11)

Output port data (R10)

Frequency output

High

Low

OFF

High

Low

Heavy load protection mode register

Battery voltage low detector data

Battery voltage low detector ON/OFF

Reset

Run

Reset

–

Stop

–

R/W

R/W WR

R/W R/W

Heavy

load

Battery

voltage

low

Normal

load

Battery

voltage

normal

S1C62N81 TECHNICAL SOFTWARE EPSON II-11

CHAPTER 1: CONFIGURATION

Table 1.4.1 (g) I/O memory map (0FBH–0FCH)

Address Comment

D3 D2 D1 D0 Name SR *1 10

0FBH

0FCH

CSDC 0 CMPDT CMPON

00 0IOC

IOC 0

I/O port P00–P03 Input/Output

LCD drive switch

Analog comparator ON/OFF

Static

+ > -

Dynamic

- > +

Off

Output Input

R/W

R/W R/W

CSDC

CMPDT

CMPON

Comparator's voltage condition:

1 = CMPP(+)input > CMPM(-)input,

0 = CMPM(-)input > CMPP(+)input

*1 Initial value following initial reset

*2 Not set in the circuit

*3 Undefined

*4 Reset (0) immediately after being read

*5 Always 0 when being read

*6 Refer to main manual

II-12 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 2: INITIAL RESET

Bit Length Address

INITIAL RESET

Internal Register Status on Initial Reset

Following an initial reset, the internal registers and internal

data memory area are initialized to the values shown in

Tables 2.1.1 and 2.1.2.

Internal Register Bit Length Initial Value Following Reset

Program counter step PCS 8 00H

Program counter page PCP 4 1H

New page pointer NPP 4 1H

Stack pointer SP 8 Undefined

Index register X 8 Undefined

Index register Y 8 Undefined

General register A 4 Undefined

General register B 4 Undefined

Interrupt flag I 1 0

Decimal flag D 1 Undefined

Zero flag Z 1 Undefined

Carry flag C 1 Undefined

Internal Data Initial Value

Memory Area Following Reset

RAM data 4 × 96 Undefined 000H–05FH

Display memory 4 × 26 Undefined 090H–0AFH

Internal I/O register See Tables 1.4.1 (a)–1.4.1 (g) 0E0H–0FCH

2.1

Table 2.1.1

Initial values of internal

registers

CHAPTER 2

Table 2.1.2

Initial values of internal data

memory area

S1C62N81 TECHNICAL SOFTWARE EPSON II-13

CHAPTER 2: INITIAL RESET

After an initial reset, the program counter page (PCP) is

initialized to 1H, and the program counter step (PCS), to

00H. This is why the program is executed from step 00H of

the first page.

The initial values of some internal registers and internal

data memory area locations are undefined after a reset. Set

them as necessary to the proper initial values in the pro-

gram.

The peripheral I/O functions (memory-mapped I/O) are

assigned to internal data memory area addresses 0E0H to

0FCH. Each address represents a 4-bit internal I/O register,

allowing access to the peripheral functions in 1-word (4-bit)

read/write units.

II-14 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 2: INITIAL RESET

Initialize Program Example

The following is a program that clears the RAM and LCD,

resets the flags, registers, timer, and stopwatch timer, and

sets the stack pointer immediately after resetting the sys-

tem.

Label Mnemonic/operand Comment

ORG 100H

JP INIT ;Jump to "INIT"

;ORG 110H

INIT RST F,0011B ;Interrupt mask, decimal

;adjustment off

;LD X,0 ;

RAMCLR LDPX MX,0 ;

CP XH,6H ;

JP NZ,RAMCLR ;

LD X,90H ;

LCPCLR LDPX MX,0 ;

CP X,0BH ;

JP NZ,LCDCLR ;

;LD A,0 ;

LD B,5 ;

LD SPL,A ;

LD SPH,B ;

;LD X,0F9H ;

OR MX,0101B ;

;LD X,0EBH ;

OR MX,0111B ;

;LD X,0E8H ;

OR MX,1111B ;

;LD X,0 ;

LD Y,0 ;

LD A,0 ;

LD B,0 ;

RST F,0 ;

EI ;Enable interrupt

Clear RAM (00H–5FH)

Enable timer interrupt

Enable input interrupt

(K03–K00)

Clear LCD (90H–AFH)

Reset timer and stopwatch

timer

Set stack pointer to 50H

2.2

Reset register flags

S1C62N81 TECHNICAL SOFTWARE EPSON II-15

CHAPTER 2: INITIAL RESET

The above program is a basic initialization program for the

S1C62N81. The setting data are all initialized as shown in

Table 2.1.1 by executing this program. When using this

program, add setting items necessary for each specific

application. (Figure 2.2.1 is the flow chart for this program.)

Initialization

Reset

I (Interrupt flag)

D (Decimal adjustment flag)

Clear RAM

Set SP

Reset timer,

stopwatch timer

Enable timer interrupt

Enable input interrupt

Reset registers (X, Y, A, B)

flags (I, Z, D, C)

EI (enable interrupt)

Clear data RAM (00H to 05FH)

Clear segment RAM (90H to 0AFH)

Set stack pointer to 50H

Enable K03–K00 input port interrupt

To next process

Interrupt flag

Decimal adjustment flag

Enable timer interrupt 2 Hz, 8 Hz, 32 Hz

Fig. 2.2.1

Flow chart of the initialization

program

Internal circuit

General register A

General register B

Index register X

Index register Y

Stack pointer SP

Interrupt flag I

Decimal flag D

Zero flag Z

Carry flag C

RAM data (00H∼5FH)

Segment data (90H∼0AFH)

Clock timer: reset, Clock timer interrupt: valid

Stopwatch timer: reset

K00–K03 interrupt: valid

Setting value

00H

50H

Table 2.2.2

Execution result of the

initialization program

II-16 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Input Ports)

PERIPHERAL CIRCUITS

Details on how to control the S1C62N81 peripheral circuit is

given in this chapter.

Input Ports

CHAPTER 3

3.1

Input port memory

map

Table 3.1.1 (a) I/O memory map

*4 Reset (0) immediately after being read

*5 Always 0 when being read

*6 Refer to main manual

*1 Initial value following initial reset

*2 Not set in the circuit

*3 Undefined

Address Comment

D3 D2 D1 D0 Name SR

0E0H

0E1H

K03 K02 K01 K00

0 0 0 K10

K03

K02

K01

K00

–

K10 –

Input port (K10)

Input port (K00–K03)

High

Low

High Low

0E5H

0E6H

KCP03 KCP02 KCP01 KCP00

0 0 0 KCP10

R/W

KCP03

KCP02

KCP01

KCP00

Input comparison register (K03)

Input comparison register (K02)

Input comparison register (K01)

Input comparison register (K00)

KCP10 0

Input comparison register (K10)

Falling

Rising

Falling Rising

R/W

S1C62N81 TECHNICAL SOFTWARE EPSON II-17

CHAPTER 3: PERIPHERAL CIRCUITS (Input Ports)

Table 3.1.1 (b) I/O memory map

*1 Initial value following initial reset

*2 Not set in the circuit

*3 Undefined

*4 Reset (0) immediately after being read

*5 Always 0 when being read

*6 Refer to main manual

Address Comment

D3 D2 D1 D0 Name SR

0E8H

0E9H

EIK03 EIK02 EIK01 EIK00

0 0 0 EIK10

R/W

EIK03

EIK02

EIK01

EIK00

EIK10 0

Interrupt mask register (K10)

Interrupt mask register (K03)

Interrupt mask register (K02)

Interrupt mask register (K01)

Interrupt mask register (K00)

Enable

Mask

Enable Mask

R/W

0EDH

0 0 IK1 IK0

IK1

IK0

Interrupt factor flag (K10)

Interrupt factor flag (K00–K03)

Yes

II-18 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Input Ports)

The S1C62N81 Series have a 4-bit input port (K00–K03) and

a 1-bit input port (K10).

The data registers for the input ports K00–K03 and K10 are

assigned to the addresses 0E0H (D0–D3) and 0E1H (D0),

respectively. The status of the input port terminals can be

read from the addresses in 4-bit units (K00–K03 and K10).

The input ports have an interrupt function that can be

controlled using the interrupt factor flags and interrupt

mask registers which have been set in each bit. See Section

3.11, "Interrupt and Halt", for details.

• Loading K00–K03 into the A register

Label Mnemonic/operand Comment

LD Y,0E0H ;Set address of port

LD A,MY ;A register ← K00–K03

As shown in Figure 3.1.1, the two instruction steps above

load the data of the input port into the A register.

Control of the input

port

K03

K02

K01

K00

A register

The data of the input port can be loaded into the B register

or MX instead of the A register.

Fig. 3.1.1

Loading the A register

Examples of input

port control program

S1C62N81 TECHNICAL SOFTWARE EPSON II-19

CHAPTER 3: PERIPHERAL CIRCUITS (Input Ports)

• Bit-unit checking of input ports

Label Mnemonic/operand Comment

DI ;Disable interrupt

LD Y,0E0H ;Set address of port

INPUT1: FAN MY,0010B ;

JP NZ,INPUT1 ;Loop until K01 becomes "0"

INPUT2: FAN MY,0010B ;

JP Z,INPUT2 ;Loop until K01 becomes "1"

This program loopes until a rising edge is input to input port

K01.

The input port can be addressed using the Y register instead

of the X register.

When the input port is changed from high level to low level with a

pull-down resistor, the signal falls following a certain delay caused

by the time constants of the pull-down resistance and the input

gate capacitance. It is therefore necessary to observe a proper

wait time before the input port data is read.

Note

II-20 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Output Ports)

Output Ports3.2

Output port memory

map

Table 3.2.1 I/O memory map

Address Comment

D3 D2 D1 D0 Name SR *1 10

0F3H

R03 R02 R01 R00 R03

R02

R01

R00

High

Low

Output port data (R00–R03)

R/W

0F4H

R12

ENV

R11 R10

FOUT

R/W R12

ENV

R11

R10

FOUT

Output port data (R12)

Inverting melody output

Melody envelope control

Output port data (R11)

Output port data (R10)

Frequency output

High

Low

OFF

*1 Initial value following initial reset

*2 Not set in the circuit

*3 Undefined

*4 Reset (0) immediately after being read

*5 Always 0 when being read

*6 Refer to main manual

S1C62N81 TECHNICAL SOFTWARE EPSON II-21

CHAPTER 3: PERIPHERAL CIRCUITS (Output Ports)

The S1C62N81 Series have 7 bits of general output ports

(R00–R03, R10–R12).

The output ports are assigned to the address 0F3H (D0–D3)

for R00–R03 and the address 0F4H (D0–D2) for R10–R12 as

the registers that can read and write. The output port termi-

nals output the contents written to the registers. In addition,

since the output status of the output port can be read via the

registers, the output ports can be controlled in each bit using

a logical operation instruction such as AND and OR.

At initial reset, the output ports go to a low level (the regis-

ters are 0).

• Loading B register data into R00–R03

Label Mnemonic/operand Comment

LD Y,0F3H ;Set address of port

LD MY,B ;R00–R03 ← B register

As shown in Figure 3.2.1, the two instruction steps above

load the data of the B register into the output ports.

Control of the output

port

D3 D2 D1 D0

Data register R00

Data register R01

Data register R02

Data register R03

B register

Examples of output

port control program

Fig. 3.2.1

Control of the output port

II-22 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Output Ports)

The output data can be taken from the A register, MX, or

immediate data instead of the B register.

• Bit-unit operation of output ports

Label Mnemonic/operand Comment

LD Y,0F3H ;Set address of port

OR MY,0010B ;Set R01 to 1

AND MY,1011B ;Set R02 to 0

The three instruction steps above cause the output port to

be set, as shown in Figure 3.2.2.

R03 R02 R01 R00

No change

Sets "1"

Sets "0"

No change

Address 0F3H D3 D2 D1 D0

Fig. 3.2.2

Setting of the output port

S1C62N81 TECHNICAL SOFTWARE EPSON II-23

CHAPTER 3: PERIPHERAL CIRCUITS (Special Use Output Ports)

Special Use Output Ports3.3

Special use output

port memory map

Table 3.3.1 I/O memory map

Address Comment

D3 D2 D1 D0 Name SR

0F4H

R12

ENV

R11 R10

FOUT

R/W R12

ENV

R11

R10

FOUT

Output port data (R12)

Inverting melody output

Melody envelope control

Output port data (R11)

Output port data (R10)

Frequency output

High

Low

OFF

*1 Initial value following initial reset

*2 Not set in the circuit

*3 Undefined

*4 Reset (0) immediately after being read

*5 Always 0 when being read

*6 Refer to main manual

II-24 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Special Use Output Ports)

In addition to the regular DC, special output can be selected

for output ports R10–R12, as shown in Table 3.3.2. Figure

3.3.1 shows the structure of output ports R10–R12.

Pin Name When Special Output is Selected

R12 MO or ENV

R10 FOUT

Control of the spe-

cial use output port

Table 3.3.2

Special output

Fig. 3.3.1

Structure of output ports

R10–R12

Address

(0F4H)

FOUT

Data bus

R10

R11

R12

Mask option

(R12)

(R11)

(R10)

or ENV

S1C62N81 TECHNICAL SOFTWARE EPSON II-25

CHAPTER 3: PERIPHERAL CIRCUITS (Special Use Output Ports)

• Melody output MO, MO or envelope output (R12)

MO and MO (or ENV) are the melody signal output pins for

driving a piezo or speaker through an amplifying transistor.

Refer to 3.10, "Melody Generator".

• FOUT (R10)

When output port R10 is set for FOUT, it outputs the fosc

clock or the divided fosc. The clock frequencies listed in

Table 3.3.3 selectable by mask option.

Label Mnemonic/operand Comment

LD Y,0F4H ;Set address of port

OR MY,0001B ;Turn on FOUT

AND MY,1110B ;Turn off FOUT

Example of special

use output port

control program

Table 3.3.3

Selectable by mask option

fosc / 1

fosc / 2

fosc / 4

fosc / 8

fosc / 16

fosc / 32

fosc / 64

fosc / 128

32,768

16,384

8,192

4,096

2,048

1,024

512

256

Setting Value fosc = 32,768

Clock Frequency (Hz)

II-26 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (I/O Ports)

3.4 I/O Ports

I/O port memory

map

Table 3.4.1 I/O memory map

Address Comment

D3 D2 D1 D0 Name SR *1 10

0F6H

P03 P02 P01 P00 P03

P02

P01

P00

–

I/O port (P00–P03)

High

Low

R/W

0FCH

00 0IOC

IOC 0

I/O port P00–P03 Input/Output

Output Input

R/W

*1 Initial value following initial reset

*2 Not set in the circuit

*3 Undefined

*4 Reset (0) immediately after being read

*5 Always 0 when being read

*6 Refer to main manual

S1C62N81 TECHNICAL SOFTWARE EPSON II-27

CHAPTER 3: PERIPHERAL CIRCUITS (I/O Ports)

The S1C62N81 contains a 4-bit general I/O port (4 bits × 1).

This port can be used as an input port or an output port,

according to I/O port control register IOC. When IOC is "0",

the port is set for input, when it is "1", the port is set for

output.

• How to set an input port

Set "0" in the I/O port control register (D0 of address 0FCH),

and the I/O port is set as an input port. The state of the I/O

port (P00–P03) is decided by the data of address 0F6H. (In

the input mode, the port level is read directly.)

• How to set an output port

Set "1" in the I/O port control register, and the I/O port is

set as an output port. The state of the I/O port is decided by

the data of address 0F6H. This data is held by the register,

and can be set regardless of the contents of the I/O control

input ports or output ports.)

The I/O control registers are cleared to "0" (input/output

ports are set as input ports), and the data registers are also

cleared to "0" after an initial reset.

Control of the I/O

port

II-28 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (I/O Ports)

• Loading P00–P03 input data into A register

Label Mnemonic/operand Comment

LD Y,0FCH ;Set address of I/O control port

AND MY,1110B ;Set port as input port

LD Y,0F6H ;Set address of port

LD A,MY ;A register ← P00–P03

As shown in Figure 3.4.1, the four instruction steps above

load the data of the I/O ports into the A register.

P03

P02

P01

P00

A register

Examples of I/O port

control program

Fig. 3.4.1

Loading into the A register

S1C62N81 TECHNICAL SOFTWARE EPSON II-29

CHAPTER 3: PERIPHERAL CIRCUITS (I/O Ports)

• Loading P00–P03 output data into A register

Label Mnemonic/operand Comment

LD Y,0FCH ;Set the address of input/output

;port control register

OR MY,0001B ;Set as output port

LD Y,0F6H ;Set the address of port

LD A,MY ;A register ← P00–P03

As shown in Figure 3.4.2, the four instruction steps above

load the data of the I/O ports into the A register.

P03 P02 P01 P00

Data register P00

Data register P01

Data register P02

Data register P03

A register D3 D2 D1 D0

Data can be loaded from the I/O port into the B register or

MX instead of the A register.

Fig. 3.4.2

Control of I/O port (input)

II-30 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (I/O Ports)

• Loading contents of B register into P00–P03

Label Mnemonic/operand Comment

LD Y,0FCH ;Set the address of input/output

;port control register

OR MY,0001B ;Set port as output port

LD Y,0F6H ;Set the address of port

LD MY,B ;P00–P03 ← B register

As shown in Figure 3.4.3, the four instruction steps above

load the data of the B register into the I/O ports.

D3 D2 D1 D0

Data register P00

Data register P01

Data register P02

Data register P03

B register

The output data can be taken from the A register, MX, or

immediate data instead of the B register.

Bit-unit operation for the I/O port is identical to that for the

input ports (K00–K03, K10) or output ports (R00–R03).

Fig. 3.4.3

Control of the I/O port (output)

S1C62N81 TECHNICAL SOFTWARE EPSON II-31

CHAPTER 3: PERIPHERAL CIRCUITS (LCD Driver)

LCD Driver3.5

LCD driver memory

map

Fig. 3.5.1

Display memory map

Address 0123456789ABCDEF

090

0A0 Display memory (write only)

32 words x 4 bits

Table 3.5.1 I/O memory map

Address Comment

D3 D2 D1 D0 Name SR

0FBH

CSDC 0 CMPDT CMPON

LCD drive switch

Analog comparator ON/OFF

Static

+ > -

Dynamic

- > +

Off

R/W R/W

CSDC

CMPDT

CMPON

Comparator's voltage condition:

1 = CMPP(+)input > CMPM(-)input,

0 = CMPM(-)input > CMPP(+)input

*1 Initial value following initial reset

*2 Not set in the circuit

*3 Undefined

*4 Reset (0) immediately after being read

*5 Always 0 when being read

*6 Refer to main manual

II-32 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (LCD Driver)

The S1C62N81 contains 128 bits of display memory in

addresses 090H to 0AFH of the data memory. Each display

memory can be assigned to any 104 bits of the 128 bits for

the LCD driver (26 SEG × 4 COM) or 78 bits of the 128 bits

(26 SEG × 3 COM) by using a mask option. The remaining

24 bits or 50 bits of display memory are not connected to

the LCD driver, and are not output even when data is writ-

ten. An LCD segment is on with "1" set in the display

memory, and off with "0" set in the display memory. Note

that the display memory is a write-only.

• LCD drive control register (CSDC)

The LCD drive control register (CSDC: address 0FBH, D3)

can be set either for dynamic drive or for static drive. Set "0"

in CSDC for 1/3 duty or 1/4 duty (time-shared) dynamic

drive. Set "1" in CSDC and the same value in the registers

corresponding to COM0 to COM2 (1/3) or COM0 to COM3

(1/4) for static drive. Figure 3.5.2 is the static drive control

of the LCD, and Figure 3.5.3 is an example of the 7-segment

LCD assignment.

Control of the LCD

driver

S1C62N81 TECHNICAL SOFTWARE EPSON II-33

CHAPTER 3: PERIPHERAL CIRCUITS (LCD Driver)

Fig. 3.5.2

LCD static drive control

Fig. 3.5.3

7-segment LCD assignment

In the assignment shown in Figure 3.5.3, the 7-segment

display pattern is controlled by writing data to display

memory addresses 090H and 091H.

g f e

091H

dcba

090H D3 D2 D1 D0

Address Register

SEG

0–25

COM

0–3

Frame frequency

LCD lighting status

COM0

COM1

COM2

COM3

SEG0–25

-V

Not lit Lit

-V

II-34 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (LCD Driver)

• Displaying 7-segment

The LCD display routine using the assignment of Figure

3.5.3 can be programmed as follows.

Label Mnemonic/operand Comment

ORG 000H

RETD 3FH ;0 is displayed

RETD 06H ;1 is displayed

RETD 5BH ;2 is displayed

RETD 4FH ;3 is displayed

RETD 66H ;4 is displayed

RETD 6DH ;5 is displayed

RETD 7DH ;6 is displayed

RETD 27H ;7 is displayed

RETD 7FH ;8 is displayed

RETD 6FH ;9 is displayed

SEVENS: LD B,0 ;Set the address of jump

LD X,090H ;Set address of display memory

JPBA

When the above routine is called (by the CALL or CALZ

instruction) with any number from "0" to "9" set in the A

are displayed according to the contents of the A register.

The RETD instruction can be used to write data to the

display memory only if it is addressed using the X register.

(Addressing using the Y register is invalid.)

Note that the stack pointer must be set to a proper value

before the CALL (CALZ) instruction is executed.

Examples of

LCD driver control

program

DisplayA resister

Fig. 3.5.4

Data set in A register and

displayed patterns

S1C62N81 TECHNICAL SOFTWARE EPSON II-35

CHAPTER 3: PERIPHERAL CIRCUITS (LCD Driver)

• Bit-unit operation of the display memory

Label Mnemonic/operand Comment

LD X,SEGBUF ;Set address display

;memory buffer

LD Y,090H ;Set address display memory

LD MX,3 ;Set buffer data

LD MY,MX ;SEG-A, B ON (●, ▲)

AND MX,1110B ;Change buffer data

LD MY,MX ;SEG-A OFF (●●, ▲)

AND MX,1101B ;Change buffer data

LD MY,MX ;SEG-B OFF (●●, ▲▲)

For manipulation of the display memory in bit-units for the

assignment of Figure 3.5.5, a buffer must be provided in

RAM to hold data. Note that, since the display memory is

write-only, data cannot be changed directly using an ALU

instruction (for example, AND or OR).

After manipulating the data in the buffer, write it into the

corresponding display memory using the transfer command.

▲●

090H D3 D2 D1 D0

Address Data

▲

●: SEG - A

: SEG - B

Fig. 3.5.5

Example of segment

assignment

II-36 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Timer)

3.6 Timer

Timer memory map

Table 3.6.1 I/O memory map

*1 Initial value following initial reset

*2 Not set in the circuit

*3 Undefined

*4 Reset (0) immediately after being read

*5 Always 0 when being read

*6 Refer to main manual

Address Comment

D3 D2 D1 D0 Name SR *1 10

0E4H

TM3 TM2 TM1 TM0

TM3

TM2

TM1

TM0

–

Timer data (clock timer 2 Hz)

Timer data (clock timer 4 Hz)

Timer data (clock timer 8 Hz)

Timer data (clock timer 16 Hz)

High

Low

0EBH

0 EIT2 EIT8 EIT32

EIT2

EIT8

EIT32

Enable

Mask

Interrupt mask register (clock timer 2 Hz)

Interrupt mask register (clock timer 8 Hz)

Interrupt mask register (clock timer 32 Hz)

R/W

0EFH

0 IT2 IT8 IT32 0

IT2

IT8

IT32

Yes

Interrupt factor flag (clock timer 2 Hz)

Interrupt factor flag (clock timer 8 Hz)

Interrupt factor flag (clock timer 32 Hz)

0F9H

0 TMRST SWRUN SWRST

TMRST

SWRUN

SWRST

Reset

Clock timer reset

Stopwatch timer RUN/STOP

Stopwatch timer reset

Reset

Run

Reset

–

Stop

–

R/W WR

S1C62N81 TECHNICAL SOFTWARE EPSON II-37

CHAPTER 3: PERIPHERAL CIRCUITS (Timer)

The S1C62N81 contains a timer with a basic oscillation of

32.768 kHz (typical). This timer is a 4-bit binary counter,

and the counter data can be read as necessary. The counter

data of the 16 Hz clock can be read by reading TM3 to TM0

(address 0E4H, D3 to D0). ("1" to "0" are set in TM3 to TM0,

corresponding to the high-low levels of the 2 Hz, 4 Hz, 8 Hz,

and 16 Hz 50 % duty waveform. See Figure 3.6.1.) The timer

can also interrupt the CPU on the falling edges of the 32 Hz,

8 Hz, and 2 Hz signals. For details, see Section 3.11, "Inter-

rupt and Halt".

Control of the timer

The timer is reset by setting "1" in TMRST (address 0F9H,

D2).

The 128 Hz to 2 Hz of the internal divider is initialized by resetting

the timer, and 128 Hz to 1 Hz of the internal divider is reset by

resetting the stopwatch timer.

The dividers of the timer and stopwatch timers are individ-

ual circuits, so resetting one circuit does not affect the

other.

Clock timer timing chart

Frequency

bit

Address

0E4H

D0 16 Hz

8 Hz

4 Hz

2 Hz

Occurrence of

32 Hz interrupt request

Occurrence of

8 Hz interrupt request

Occurrence of

2 Hz interrupt request

Fig. 3.6.1

Output waveform of

timer and interrupt timing

Note

II-38 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Timer)

• Initializing the timer

Label Mnemonic/operand Comment

LD Y,0F9H ;Set address of the timer

;reset register

OR MY,0100B ;Reset the timer

The two instruction steps above are used to reset (clear

TM0–TM3 to 0) and restart the timer. The TMRST register is

cleared to "0" by hardware 1 clock after it is set to "1".

• Loading the timer

Label Mnemonic/operand Comment

LD Y,0E4H ;Set address of

;the timer data (TM0 to TM3)

LD A,MY ;Load the data of

;TM0 to TM3 into A register

As shown in Table 3.6.2, the two instruction steps load the

data of TM0 to TM3 into the A register.

TM3 (2 Hz)

TM2 (4 Hz)

TM1 (8 Hz)

TM0 (16 Hz)

A register

Table 3.6.2

Loading the timer data

Examples of timer

control program

S1C62N81 TECHNICAL SOFTWARE EPSON II-39

CHAPTER 3: PERIPHERAL CIRCUITS (Timer)

Note

• Checking timer edge

Label Mnemonic/operand Comment

LD X,TMSTAT ;Set address of the timer edge counter

CP MX,0 ;Check whether the timer edge

;counter is "0"

JP Z,RETURN ;Jump if "0" (Z-flag is "1")

LD Y,0E4H ;Set address of the timer

LD A,MY ;Read the data of TM0 to TM3

;into A register

LD Y,TMDTBF ;Set address of the timer data buffer

XOR MY,A ;Did the count on the timer

;change?

FAN MY,0100B ;Check bit D2 of the timer data buffer

LD MY,A ;Set the data of A register into

;the timer data buffer

JP Z,RETURN ;Jump, if the Z-flag is "1"

ADD MX,0FH ;Decrement the timer edge counter

;

RETURN: RET ;Return

This program takes a subroutine form. It is called at short

intervals, and decrements the data at address TMSTAT every

125 ms until the data reaches "0". The timing chart is

shown in Figure 3.6.2. The timer can be addressed using

the X register instead of the Y register.

TMSTAT and TMDTBF may be any address in RAM and not

involve a hardware function.

125 ms

Timer edge counter (TMSTAT) decrementing timing

TM2

Fig. 3.6.2

Timing of the timer

edge counter

II-40 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Stopwatch Timer)

3.7 Stopwatch Timer

Table 3.7.1 I/O memory map

Stopwatch timer

memory map

Address Comment

D3 D2 D1 D0 Name SR *1 10

0E2H

0E3H

SWL3 SWL2 SWL1 SWL0

SWH3 SWH2 SWH1 SWH0

SWL3

SWL2

SWL1

SWL0

SWH3

SWH2

SWH1

SWH0

MSB

Stopwatch timer

1/100 sec (BCD)

LSB

MSB

Stopwatch timer

1/10 sec (BCD)

LSB

0EAH

0 0 EISW1 EISW0

EISW1

EISW0

Interrupt mask register (stopwatch 1 Hz)

Interrupt mask register (stopwatch 10 Hz)

Enable

Mask

R/W

0EEH

0 0 ISW1 ISW0

ISW1

ISW0

Interrupt factor flag (stopwatch 1 Hz)

Interrupt factor flag (stopwatch 10 Hz)

Yes

0F9H

0 TMRST SWRUN SWRST

TMRST

SWRUN

SWRST

Reset

Clock timer reset

Stopwatch timer RUN/STOP

Stopwatch timer reset

Reset

Run

Reset

–

Stop

–

R/W WR

*1 Initial value following initial reset

*2 Not set in the circuit

*3 Undefined

*4 Reset (0) immediately after being read

*5 Always 0 when being read

*6 Refer to main manual

S1C62N81 TECHNICAL SOFTWARE EPSON II-41

CHAPTER 3: PERIPHERAL CIRCUITS (Stopwatch Timer)

The S1C62N81 contains 1/100 sec and 1/10 sec stopwatch

timers.

This timer can be loaded in 4-bit units. Starting, stopping,

and resetting the timer can be controlled by register.

Figure 3.7.1 shows the operation of the stopwatch timer.

Control of the stop-

watch timer

Fig. 3.7.1

Stopwatch timer

operating timing

Address

Stopwatch timer (SWH) timing chart

Occurrence of

10 Hz interrupt request

Occurrence of

1 Hz interrupt request

0E3H

(1/10 sec BCD)

0E2H

(1/100 sec BCD)

II-42 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Stopwatch Timer)

• Initializing the stopwatch timer

Label Mnemonic/operand Comment

LD Y,0F9H ;Set address of the SWRST register

OR MY,0001B ;Reset the stopwatch timer

The two instruction steps above reset the stopwatch timer.

(SWL3 to SWL0, SWH3 to SWH0 are all cleared to "0".)

The stopwatch timer is reset by setting "1" in the SWRST register.

However, the SWRST register is cleared to "0" by hardware 1

clock after it is set to "1".

• Starting the stopwatch timer

Label Mnemonic/operand Comment

LD Y,0F9H ;Set address of SWRUN register

OR MY,0010B ;Start the stopwatch timer

The two instruction steps above run the stopwatch timer of

SWL0 to SWL3, and SWH0 to SWH3 (addresses 0E2H and

0E3H, respectively).

• Stopping the stopwatch timer

Label Mnemonic/operand Comment

LD Y,0F9H ;Set address of SWRUN register

AND MY,1101B ;Stop the stopwatch timer

The two instruction steps above stop the stopwatch timer of

SWL0 to SWL3, and SWH0 to SWH3 (addresses 0E2H and

0E3H, respectively).

Note

Examples of stop-

watch timer control

program

S1C62N81 TECHNICAL SOFTWARE EPSON II-43

CHAPTER 3: PERIPHERAL CIRCUITS (Stopwatch Timer)

• Loading the stopwatch timer

Label Mnemonic/operand Comment

LD Y,0E2H ;Set address of the SWL of

;the stopwatch

LDPY A,MY ;Read the data of SWL0 to SWL3

;into A register

LD B,MY ;Read the data of SWH0 to SWH3

;into B register

The three instruction steps above reads the contents of the

stopwatch timer into A register and B register. (Also see

Table 3.7.2.)

A read-in error caused by a carry from the SWL is not taken into

account in this program. You are recommended to add a handling

routine in your application.

Table 3.7.2

Data load into A register

and B register

SWH3 SWH2 SWH1 SWH0

B register

SWL3 SWL2 SWL1 SWL0

A register D3 D2 D1 D0

Note

II-44 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (BLD Circuit and Heavy Load Protection Function)

3.8 Battery Voltage Low Detection (BLD) Circuit

and Heavy Load Protection Function

The S1C62N81 Series has built-in battery voltage low detec-

tion circuit and drop in power battery voltage may be de-

tected by controlling the register on the I/O memory. Crite-

ria voltages are as follows:

Model Criteria Voltage

S1C62N81/62A81 2.4 V ± 0.15 V

S1C62L81/62B81 1.2 V ± 0.10 V

Moreover, when the battery load becomes heavy, such as

during external piezo buzzer driving or external lamp light-

ing, heavy load protection function is built-in in case the

battery voltage drops. S1C62L81/62B81 operates at 0.9 V

due to the BLD circuit and heavy load protection function.

BLD circuit and

heavy load protec-

tion function mem-

ory map

Table 3.8.1 I/O memory map

Address Comment

D3 D2 D1 D0 Name SR

0FAH

HLMOD 0 BLDDT BLDON HLMOD

BLDDT

BLDON

0 ON OFF

Heavy load protection mode register

BLD data

BLD ON/OFF

RR/W R/W

Heavy

load

Battery

voltage

low

Normal

load

Battery

voltage

normal

*1 Initial value following initial reset

*2 Not set in the circuit

*3 Undefined

*4 Reset (0) immediately after being read

*5 Always 0 when being read

*6 Refer to main manual

S1C62N81 TECHNICAL SOFTWARE EPSON II-45

CHAPTER 3: PERIPHERAL CIRCUITS (BLD Circuit and Heavy Load Protection Function)

Control of the BLD

circuit

The BLD circuit will turn ON by writing "1" on the BLDON

detection will be performed. By writing "0" on the BLDON

However, in order to obtain a stable detection result, it is

necessary to turn the BLD circuit ON for at least 100 µs.

Accordingly, reading out the detection result from the

BLDDT register is performed through the following proce-

dures:

➀Set the BLDON register to "1".

➁Provide at least 100 µs waiting time.

➂Set the BLDON register to "0".

➃Read-out from the BLDDT register.

Note, however, that when S1C62N81 is to be used with the

normal system clock at fosc = 32.768 kHz, there is no need

for the waiting time stated in the above procedure ➁ since 1

instruction cycle will take longer than 100 µs.

Because the power current consumption of the IC becomes

large when the BLD circuit is operated, turn the BLD circuit

OFF when not in use. The operation timing chart is shown

in Figure 3.8.1.

Fig. 3.8.1

Timing chart of

battery voltage low

detection operation

through the BLDON

Battery voltage

Criteria voltage

BLDON register

BLD circuit

BLDDT register

HLMOD register

100 µs or more

Label Mnemonic/Operand Comment

LD X,0FAH ;Sets the address of BLDON

OR MX,0001B ;Sets BLDON to "1"

AND MX,1110B ;Sets BLDON to "0"

LD A,MX ;Loads the detection result

;into the A register

Example of BLD

circuit control

program

II-46 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (BLD Circuit and Heavy Load Protection Function)

Heavy load protec-

tion function

There are two ways to operate the heavy load protection

function:

• Operation through the HLMOD register

The heavy load protection function may be operated by

writing "1" on the HLMOD register (address 0FAH, D3,

R/W). Simultaneously, the BLD circuit will turn ON and

battery voltage low detection by hardware every 2 Hz (0.5

sec) will automatically be performed.

Operation through the HLMOD register is useful when

heavy load can be anticipated such as when S1C62N81

drives the piezo buzzer. The operation timing chart is

shown in Figure 3.8.2.

• Operation through the BLDON register

The BLD circuit will turn ON by writing "1" on the

BLDON register (address 0FAH, D0, R/W) and battery

voltage low detection will be performed. By writing "0" on

the BLDON register, the detection result is stored in the

BLDDT register. If this results in the battery voltage being

lower than the criteria voltage, the heavy load protection

function will operate. In other words, the BLD circuit in

this case serves as a sensor for detecting the operational

state of the heavy load protection function.

Battery voltage

Criteria voltage

HLMOD register

Heavy load

protection mode

2 Hz clock

BLD circuit

BLDDT

BLDON register

Fig. 3.8.2

Timing chart of

battery voltage low

detection opera-

tion through the

HLMOD register

S1C62N81 TECHNICAL SOFTWARE EPSON II-47

CHAPTER 3: PERIPHERAL CIRCUITS (BLD Circuit and Heavy Load Protection Function)

Operation through the BLDON circuit is useful as a

measure against unforeseen circumstances, such as drop

in supply voltage due to expiring battery life, by way of

promptly operating the heavy load protection function.

The following procedures for controlling the BLD circuit

by the software are the same as those described in "Con-

trol of the BLDON circuit":

➀Set the BLDON register to "1".

➁Provide at least 100 µs waiting time.

➂Set the BLDON register to "0".

➃Read-out from the BLDDT register.

If the battery voltage is lower than the criteria voltage, the

heavy load protection function will automatically start

operating after the above procedure ➂ has been per-

formed.

Because battery voltage low detection by hardware every

2 Hz (0.5 sec) will automatically be performed when the

heavy load protection function operates, refrain from

operating the BLD circuit with the software in order to

minimize power current consumption. The operation

timing chart is shown in Figure 3.8.3.

Fig. 3.8.3

Timing chart of heavy

load protection

function operation

through the BLDON

100 µs or more

Battery voltage

Criteria voltage

BLDON register

2 Hz clock

BLD circuit

BLDDT register

Heavy load

protection mode

HLMOD register

II-48 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (BLD Circuit and Heavy Load Protection Function)

Examples of heavy

load protection

function control

program

• Operation through the HLMOD register

This is a sample program when lamp is driven with the

R00 terminal during performance of heavy load protec-

tion.

Label Mnemonic/Operand Comment

LD X,0FAH ;Sets the address of HLMOD

OR MX,1000B ;Sets to the heavy protection mode

LD Y,0F3H ;Sets the address of R0n port

OR MY,0001B ;Turns lamp ON

LD Y,0F3H ;Sets the R0n port address

AND MY,1110B ;Turns the lamp on

CALL WT1S ;1 second waiting time (software timer)

AND MX,0111B ;Cancels the heavy load protection mode

In the above program, the heavy load protection mode is

canceled after 1 second waiting time provided as the time

for the battery voltage to stabilize after the lamp is turned

off; however, since this time varies according to the

nature of the battery, time setting must be done in accor-

dance with the actual application.

S1C62N81 TECHNICAL SOFTWARE EPSON II-49

CHAPTER 3: PERIPHERAL CIRCUITS (BLD Circuit and Heavy Load Protection Function)

• Operation through the BLDON register

Label Mnemonic/Operand Comment

LD X,0FAH ;Sets the HLMOD/BLDDT address

FAN MX,1010B ;Checks the HLMOD/BLDDT bits

JP NZ,HLMOD ;Heavy load protection mode

OR MX,0001B ;Sets the BLDON to "1"

AND MX,1110B ;Sets the BLDON to "0"

FAN MX,0010B ;Checks the BLDDT bit

JP Z,HLMOD ;Shifts the mode to

;the heavy load protection mode

LD Y,FLAG

AND MY,0 ;Resets the flag to "0"

RET

;

HLMOD: LD Y,FLAG

OR MY,1 ;Sets the flag to "1"

RET

The above program operates the heavy load protection

function by using the BLDON register. In the normal

operation mode, battery voltage low detection is done

from the BLDON register and when the battery voltage

drops below the criteria voltage, the mode shifts to the

heavy load protection mode. In the heavy load protection

mode, battery voltage low detection by the hardware is

done every 2 Hz and the detection result is stored in the

BLDDT register. Because of this, the BLDDT register will

be "1" during the heavy load protection mode. Moreover,

in the above program, battery voltage low detection by the

BLDON is halted during the heavy load protection mode.

If the battery voltage become grater than the criteria

voltage, the BLDDT register value will become "0" and

hence, battery voltage low detection through the BLDON

value. When used as a sub-routine, the above program

will enable the user to determine whether the present

operation mode is the normal operation mode (flag = "0")

or the heavy load protection mode (flag = "1").

The flow chart for the above program is shown in the next

page.

II-50 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (BLD Circuit and Heavy Load Protection Function)

Fig. 3.8.4

Flow chart of operation

through the BLDON register

Start

RET

FLAG←0

HLMOD?

BLDDT?

BLDON←1

BLDON←0

FLAG←1

S1C62N81 TECHNICAL SOFTWARE EPSON II-51

CHAPTER 3: PERIPHERAL CIRCUITS (Analog Comparator)

3.9 Analog Comparator

The S1C62N81 contains an analog comparator (CMP) the

data of which can be read by software. This circuit can be

turned on and off to save power. The CMPON bit controls

analog comparator (CMP) power on/off. At initial reset, the

CMP circuit is off. While the circuit is not in use, keep this

bit set to "0" to save power.

The output data of the analog comparator appears in

CMPDT, this bit is "1" when CMPP > CMPM, and "0" when

CMPP < CMPM. If the CMPON bit is "0", the CMPDT bit is

fixed at "1".

Analog comparator

memory map

Table 3.9.1 I/O memory map

Address Comment

D3 D2 D1 D0 Name SR

0FBH

CSDC 0 CMPDT CMPON

LCD drive switch

Analog comparator ON/OFF

Static

+ > -

Dynamic

- > +

Off

R/W R/W

CSDC

CMPDT

CMPON

Comparator's voltage condition:

1 = CMPP(+)input > CMPM(-)input,

0 = CMPM(-)input > CMPP(+)input

*1 Initial value following initial reset

*2 Not set in the circuit

*3 Undefined

*4 Reset (0) immediately after being read

*5 Always 0 when being read

*6 Refer to main manual

II-52 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Analog Comparator)

Example of CMP

control program

(when fosc = 32.768 kHz)

Label Mnemonic/operand Comment

LD X,0FBH ;Set CMP circuit address

OR MX,0001B ;CMP circuit on

LD A,08H ;

LOOP: ADD A,01H ; Wait about 3 ms

JP NZ,LOOP ;

LD A,MX ;A register ← CMPDT

AND MX,1110B ;CMP circuit off

Execution of the above program loads CMP output data

CMPDT into D1 of the A register.

It takes about 3 ms for the CMP output to become stable

when the circuit is turned on. Therefore, the program must

include a wait time of at least 3 ms before the output data is

loaded after the CMP circuit has been turned on.

S1C62N81 TECHNICAL SOFTWARE EPSON II-53

CHAPTER 3: PERIPHERAL CIRCUITS (Melody Generator)

3.10 Melody Generator

Melody generator

memory map

Table 3.10.1 I/O memory map

Address Comment

D3 D2 D1 D0 Name SR *1 10

0ECH

0 0 0 IMEL

IMEL 0

Interrupt factor flag (melody)

Yes No

0F0H

0F1H

0F2H

MAD3 MAD2 MAD1 MAD0

0 MAD6 MAD5 MAD4

CLKC1 CLKC0 TEMPC MELC

R/W

MAD3

MAD2

MAD1

MAD0

MAD6

MAD5

MAD4

Melody ROM address (AD6, MSB)

Melody ROM address (AD5)

Melody ROM address (AD4)

CLKC1

CLKC0

TEMPC

MELC

CLKC1(0)&CLKC0(0) : melody speed 1

CLKC1(0)&CLKC0(1) : melody speed 8

CLKC1(1)&CLKC0(0) : melody speed 16

CLKC1(1)&CLKC0(1) : melody speed 32

Tempo change control

Melody control ON/OFF

Melody ROM address (AD3)

Melody ROM address (AD2)

Melody ROM address (AD1)

Melody ROM address (AD0, LSB)

High

Low

High

Low

High

Low

OFF

R/W

*1 Initial value following initial reset

*2 Not set in the circuit

*3 Undefined

*4 Reset (0) immediately after being read

*5 Always 0 when being read

*6 Refer to main manual

II-54 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Melody Generator)

There are 7 bits for melody start address setting.

Address setting

(Addresses 0F0H and

0F1H)

Fig. 3.10.1

Set of melody ROM

address

–MSB

↓

MAD6

AD5

↓

MAD5

AD4

↓

MAD4

0F1H AD3

↓

MAD3

AD2

↓

MAD2

AD1

↓

MAD1

LSB

↓

MAD0

0F0H

The user programmable area is from 00H to 04FH (80 words).

Address 0F2H (4 bits) is for melody control.

MELC: (1)Melody start when this bit is set to "1".

(2)Melody stop when this bit is set to "0" and there is

an end bit come from melody ROM.

TEMPC: Selection of tempo (TEMPC0 or TEMPC1); chosen

by mask option. Two tempos (TEMPC0 and

TEMPC1) can be chosen out of 16 tempos.

0: TEMPC0

1: TEMPC1

(See S1C62N81 Technical Hardware, 4.11, "Play-

ing tempo".)

CLKC1, CLKC0: These two bits are combined to set the play

speed.

Note

Play mode control

Description

Table 3.10.2

Set of play speed

CLKC1 CLKC0

Play as normal speed

Play as normal speed 8

Play as normal speed 16

Play as normal speed 32

Play Speed

S1C62N81 TECHNICAL SOFTWARE EPSON II-55

CHAPTER 3: PERIPHERAL CIRCUITS (Melody Generator)

(1)One shot

In this mode, only one melody is played.

The control procedure is as follow:

When the MELC bit is set to "1", it makes the melody

play. The user's program should set this bit to "0" before

the end bit from the melody ROM. If not, the function

will be like the level hold mode (see next function).

Play mode

Fig. 3.10.2

Control procedure of

one shot mode

Set melody address

Set MELC bit to "1"

Set MELC bit to "0"

Set melody interrupt

mask enable

Jump to

melody subroutine

Melody end

interrupt

10AH

Melody subroutine

Read interrupt flag

to clear

RET

MELC

MO Playing

Interrupt generate by END data setting

II-56 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Melody Generator)

(2)Level hold

In this mode, after one melody has been played, the user

can change the next play to any other melody. If there is

no change, the melody is played repeatedly. The control

procedure is as follows:

MELC

MO Melody 1

Interrupt generate

Melody 2 Melody N - 1 Melody N

Fig. 3.10.3

Control procedure of level

hold mode

Set melody1 address

Set MELC bit to "1"

Set melody 2 address

Enable interrupt

Jump to

melody subroutine

Melody 1 end

interrupt

10AH

INC n

Set MELC bit to "0"

Read interrupt factor

flag to clear

Set counter n = 0

Melody 2 end

interrupt

Melody 3 end

interrupt

Melody 4 end

interrupt

n = ?

n = N - 1

Set melody 3 address

Select tempo

n = 1

RET

Set melody 4 address

Select tempo

n = 2 N

S1C62N81 TECHNICAL SOFTWARE EPSON II-57

CHAPTER 3: PERIPHERAL CIRCUITS (Melody Generator)

(3)Retrigger play

In this mode, the melody can be stopped anywhere dur-

ing playing, and it can be set to any another melody. The

control procedure is as follows:

With this function, the user can force the melody to stop

if there is a rest note with the End data = "1" in the

melody ROM (See melody ROM data setting).

Set melody n address

Set MELC bit to "1"

Set MELC bit to "0"

Jump to

melody subroutine

Melody n end

interrupt

10AH

Melody subroutine

RET

Set melody address

Set MELC bit to "1"

Set MELC bit to "0"

Enable interrupt

Mid-way of

melody 1

Start of

melody n

MELC

MO Melody 1

Melody 1 stopped mid-way Interrupt generate by END data setting

Melody n

Fig. 3.10.4

Control procedure of

retriggrer play mode

II-58 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Melody Generator)

(1)Tempo

Tempo selection is asigned to address 0F2H bit D1

(TEMPC).

This bit should be set at the same time that the MELC bit

is set to "1". During playing, this bit will have no func-

tion for the melody playing. But in the level hold mode,

when the next melody is loading, TEMPC will also be

loaded. The tempo will then be changed. The control

procedure is as follows:

Tempo and speed control

Set TEMPC bit to "1"

Set melody 2 address

Enable interrupt

Jump to

melody subroutine

Melody 1 end

interrupt

10AH

Melody subroutine

RET

MELC

MO Melody 1 with tempo 0

Set TEMPC

bit to "0"

Set MELC bit to "1"

Interrupt generate by END data setting

Melody 2 with tempo 1

Melody 2 end

interrupt

Set melody 1 address

Fig. 3.10.5

Control procedure

of tempo

S1C62N81 TECHNICAL SOFTWARE EPSON II-59

CHAPTER 3: PERIPHERAL CIRCUITS (Melody Generator)

(2)Speed

Speed control is asigned to address 0F2H, bits D2 and

D3 (CLKC0 and CLKC1). These two bits are controlled

independently. The user can change the speed during

playing, or start with a different speed. The control

procedure is as follows:

0F2H D3 D2 D1 D0

0001→Melody start with TEMPC0, speed normal

0101→Melody start with TEMPC0, speed × 8

1001→Melody start with TEMPC0, speed × 16

1101→Melody start with TEMPC0, speed × 32

0011→Melody start with TEMPC1, speed normal

0111→Melody start with TEMPC1, speed × 8

1011→Melody start with TEMPC1, speed × 16

1111→Melody start with TEMPC1, speed × 32

II-60 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Melody Generator)

Example of changing speed during playing:

Set MELC bit to "0"

Enable interrupt

Set 0F2H to "4"

Set melody 1 address

Set MELC bit to "1"

CLKC1

MO Normal speed

Interrupt generate by END data setting

CLKC0

MELC

Speed x 8

One melody

Fig. 3.10.6

Control procedure of

play speed

S1C62N81 TECHNICAL SOFTWARE EPSON II-61

CHAPTER 3: PERIPHERAL CIRCUITS (Melody Generator)

A melody interrupt occurs when the melody ROM data is

read out with the end bit set to "1". This indicates the end

of melody playing.

0E7H, D0: Interrupt mask bit

D0: 1Enable interrupt at the end of melody play.

D0: 0Interrupt cannot be generated even if play

is ending.

0ECH, D0: Interrupt factor flag

This bit will be reset to "0" when the user reads it.

D0: 1Interrupt has occured already, and pro-

gram will jump to interrupt vector 10AH.

Because the melody interrupt has the

highest priority, the interrupt service will

finish first, and this flag should be read to

be cleared.

D0: 0Interrupt has not been generated yet.

Volume: 00H–4FH (80 words)

Word: 9 bits/word

Refer to data setting as below:

D8 D7 D6 D5 D4 D3 D2 D1 D0

ATK Note data Scale address data End

data (Scale ROM address) data

Melody interrupt

Melody ROM

Table 3.10.3

Melody ROM data

II-62 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Melody Generator)

D0: End Data

Melody play will stop after the note playing when this data is

set to "1".

D1–D4: Scale Address Data (Scale ROM address)

What pitch is used depends on the address point of the

scale ROM and the scale data contained. (See scale ROM

data setting.)

D5–D7: Note Data

Note data table as below:

D8: ATK Data

There will be a short break (≈12 ms) before the note playing

if this data is set to "1". Usually, two notes of the same

pitch are separated with this function, otherwise the two

notes will play continuously without any break.

In each melody first word, set this data to "1". Otherwise,

there will be no melody play even if the user starts play.

Next, according to the user's definition it can set to "1" or

"0". If the hardware mask option selects the R12 envelope

function, this data also controls the note output by enve-

lope.

Note

10101010

D6 11001100

D5 11110000

Table 3.10.4

Note data

End data

(D0)

Read

MO 1 note play 1 note play 1 note play

001

Interrupt

Fig. 3.10.7

End data

ATK data

(D8)

1 1 1 0

Note 1 pla

Note 2 pla

Note 3 pla

Note 4 pla

Envelope

Fig. 3.10.8

Waveform of envelope

S1C62N81 TECHNICAL SOFTWARE EPSON II-63

CHAPTER 3: PERIPHERAL CIRCUITS (Melody Generator)

Volume: 00H–0FH (16 words)

Word: 8 bits/word

Address 0FH is set to a rest note. The data contained is not

connected with the scale. The scale may be selected accord-

ing to the definition of the scale ROM address, which is

defined by melody ROM data D4–D1. The scale data defini-

tion is as the table on the next page. The user has the

choice of 15 types of scale from this table.

Melody ROM

(D4–D1) Scale ROM data C major

00H 04H →C4 (Do)

01H 20H →D4 (Re)

02H 3BH →E4 (Mi)

03H 44H →F4 (Fa)

0EH C4H →C6 (Do)

0FH C4H →Rest

Scale ROM

II-64 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Melody Generator)

For level hold

Label Mnemonic/operand Comment

200 LD A,00H ;Set counter (melody point)

LD M0,A

LD X,0F0H ;Set first melody address (00)

LD MX,00H

INC X

LD MX,00H

LD Y,0F2H ;Start melody with TEMPC0

LD MY,01H

LD X,0F0H ;Set second melody address (06)

LD MX06H

INC X

LD MX,00H

LD Y,0E7H ;Enable melody interrupt mask

LD MY,01H

EI ;Enable interrupt

10A PSET 004H

JP 000H

400 PUSH XL

PUSH XH

PUSH YL

PUSH YH

PUSH A

INC M0 ;Melody pointer increment

LD A,M0 ;Decide which melody

CP A,01H

JP Z,MELDY3

CP A,02H

JP Z,MELDY4

CP A,03H

JP Z,MELDY5

CP A,04H

JP Z,MELDY6

CP A,05H

JP Z,MELSTP

Examples of

melody control

program

S1C62N81 TECHNICAL SOFTWARE EPSON II-65

CHAPTER 3: PERIPHERAL CIRCUITS (Melody Generator)

JP MELEND

MELDY3 LD X,0F0H ;Set MEL3 address (0A)

LD MX,0AH

INC X

LD MX,00H

JP MELSTP

MELDY4 LD X,0F0H ;Set MEL4 address (12)

LD MX,02H

INC X

LD MX,01H

JP MELSTP

MELDY5 LD X,0F0H ;Set MEL5 address (28)

LD MX,08H

INC X

LD MX,02H

LD Y,0F2H ;Set TEMPC1 for MEL6

LD MY,03H

JP MELSTP

MELDY6 LD X,0F0H ;Set MEL6 address (30)

LD MX,00H

INC X

LD MX,03H

MELSTP LD Y,0F2H ;Melody stop after end

LD MY,00H

MELEND LD Y,0ECH ;Read clear interrupt factor flag

LD A,MY

POP A

POP YH

POP YL

POP XH

POP XL

RET

II-66 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Melody Generator)

For one shot

Label Mnemonic/operand Comment

LD X,0F0H ;Set melody address

LD MX,00H

INC X

LD MX,00H

LD Y,0F2H ;Set melody start

LD MY,01H

LD MY,00H ;Set MELC to "0"

LD X,0E7H ;Enable melody interrupt mask

LD MX,01H

EI ;Enable interrupt

For retrigger

Label Mnemonic/operand Comment

LD X,0F0H ;Set melody 1 address

LD MX,00H

INC X

LD MX,00H

LD Y,0F2H ;Set melody start

LD MY,01H

LD MY,00H ;Set MELC to "0" ← Start of melody 1

LD X,0E7H ;Enable melody

LD MX,01H ;Interrupt mask

EI ;Enable interrupt

LD X,0F0H ;Set melody n address

LD MX,04H

INC X

LD MX,02H

LD Y,0F2H ;Retrigger melody with

LD MY,07H ;TEMPC1, speed × 8 ← Mid-way through melody 1

LD MY,06H ;Set MELC to "0" ← Start of melody n

S1C62N81 TECHNICAL SOFTWARE EPSON II-67

CHAPTER 3: PERIPHERAL CIRCUITS (Interrupt and Halt)

3.11 Interrupt and Halt

Table 3.11.1 (a) I/O memory map

Interrupt memory

map

Address Comment

D3 D2 D1 D0 Name SR *1 10

0E5H

0E6H

0E7H

KCP03 KCP02 KCP01 KCP00

0 0 0 KCP10

0 0 0 EIMEL

R/W

KCP03

KCP02

KCP01

KCP00

Input comparison register (K03)

Input comparison register (K02)

Input comparison register (K01)

Input comparison register (K00)

KCP10 0

EIMEL 0 Enable Mask

Input comparison register (K10)

Falling

Rising

Interrupt mask register (melody)

Falling Rising

R/W

0E8H

EIK03 EIK02 EIK01 EIK00

R/W

EIK03

EIK02

EIK01

EIK00

Interrupt mask register (K03)

Interrupt mask register (K02)

Interrupt mask register (K01)

Interrupt mask register (K00)

Enable

Mask

*1 Initial value following initial reset

*2 Not set in the circuit

*3 Undefined

*4 Reset (0) immediately after being read

*5 Always 0 when being read

*6 Refer to main manual

II-68 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Interrupt and Halt)

Table 3.11.1 (b) I/O memory map

Address Comment

D3 D2 D1 D0 Name SR *1 10

0E9H

0EAH

0EBH

0 0 0 EIK10

0 0 EISW1 EISW0

0 EIT2 EIT8 EIT32

EIK10 0

Interrupt mask register (K10)

EISW1

EISW0

EIT2

EIT8

EIT32

Enable

Mask

Interrupt mask register (stopwatch 1 Hz)

Interrupt mask register (stopwatch 10 Hz)

Enable Mask

Interrupt mask register (clock timer 2 Hz)

Interrupt mask register (clock timer 8 Hz)

Interrupt mask register (clock timer 32 Hz)

Enable

Mask

R/W

0ECH

0 0 0 IMEL

IMEL 0

Interrupt factor flag (melody)

Yes No

*1 Initial value following initial reset

*2 Not set in the circuit

*3 Undefined

*4 Reset (0) immediately after being read

*5 Always 0 when being read

*6 Refer to main manual

S1C62N81 TECHNICAL SOFTWARE EPSON II-69

CHAPTER 3: PERIPHERAL CIRCUITS (Interrupt and Halt)

Table 3.11.1 (c) I/O memory map

Address Comment

D3 D2 D1 D0 Name SR *1 10

0EDH

0EEH

0EFH

00IK1IK0

0 0 ISW1 ISW0

0 IT2 IT8 IT32

IK1

IK0

Interrupt factor flag (K10)

Interrupt factor flag (K00–K03)

ISW1

ISW0

IT2

IT8

IT32

Yes

Interrupt factor flag (stopwatch 1 Hz)

Interrupt factor flag (stopwatch 10 Hz)

Yes

Interrupt factor flag (clock timer 2 Hz)

Interrupt factor flag (clock timer 8 Hz)

Interrupt factor flag (clock timer 32 Hz)

Yes

*1 Initial value following initial reset

*2 Not set in the circuit

*3 Undefined

*4 Reset (0) immediately after being read

*5 Always 0 when being read

*6 Refer to main manual

II-70 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Interrupt and Halt)

The S1C62N81 supports four types of a total of 11

interrupts. There are three timer interrupts (2 Hz, 8 Hz, 32

Hz), two stopwatch interrupts (1 Hz, 10 Hz), five input

interrupts (K00–K03, K10) and one melody interrupt.

The 11 interrupts are individually enabled or masked (dis-

abled) by interrupt mask registers. The EI and DI instruc-

tions can be used to set or reset the interrupt flag (I), which

enables or disables all the interrupts at the same time.

Individual vector addresses are assigned to the four types of

interrupt. The priority of the interrupts is determined by the

hardware. The priority of the 2 Hz, 8 Hz, and 32 Hz timer

interrupts where the vector address is the same is deter-

mined by the software. The priority of the stopwatch inter-

rupts between 1 Hz and 10 Hz is also determined by soft-

ware.

When an interrupt is accepted, the interrupt flag (I) is reset,

and cannot accepts any other interrupts (DI state).

Restart from the halt state created by the HALT instruction,

is done by interrupt.

Control of interrupts

and halt

S1C62N81 TECHNICAL SOFTWARE EPSON II-71

CHAPTER 3: PERIPHERAL CIRCUITS (Interrupt and Halt)

• Interrupt factor flags

This flag is set when any of the K00 to K03 input interrupts

occurs. The interrupt factor flag (IK0) is set to "1" when the

contents of the input (K00–K03) and the input comparison

corresponding interrupt mask register (EIK00–EIK03) is "1".

The contents of the IK0 flag can be loaded by software to

determine whether the K00–K03 input interrupts have

occured.

The flag is reset when loaded by software. (See Figure

3.11.1.)

IK0

Address 0E5H

Address 0E8H

Input interrupt mask register

(EIK00–EIK03)

Input interrupt factor

flag register (IK0)

INT

(Interrupt request)

Interrupt flag (I)

K03

K02

K01

K00

Input comparison

Data bus

Fig. 3.11.1

K00–K03

input interrupt circuit

II-72 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Interrupt and Halt)

This flag is set when the K10 input interrupt occurs.

The interrupt factor flag (IK1) is set to "1" when the contents

of the input (K10) and the interrupt differential register

(KCP10) do not match, and the corresponding interrupt

mask register (EIK10) is "1".

The contents of the IK1 flag can be loaded by software to

determine whether K10 input interrupt has occured.

The flag is reset when loaded by software. (See Figure

3.11.2.)

Address 0E9H

Input interrupt mask register

(EIK10)

Input interrupt factor

flag register (IK1)

INT

(Interrupt request)

Interrupt flag (I)

K10

Input comparison

Address 0E1H

Data bus

Address 0E6H

Fig. 3.11.2

K10 input interrupt circuit

IK1

S1C62N81 TECHNICAL SOFTWARE EPSON II-73

CHAPTER 3: PERIPHERAL CIRCUITS (Interrupt and Halt)

This flag is set to "1" when a falling edge is detected in the

timer TM1 (32 Hz) signal.

The contents of the IT32 flag can be loaded by software to

determine whether a 32 Hz timer interrupt has occured.

The flag is reset, when it is loaded by software. (See Figure

3.11.3.)

This flag is set to "1" when a falling edge is detected in the

timer TM1 (8 Hz) signal.

The contents of the IT8 flag can be loaded by software to

determine whether an 8 Hz timer interrupt has occured.

The flag is reset, when it is loaded by software. (See Figure

3.11.3.)

This flag is set to "1" when a falling edge is detected in the

timer TM1 (2 Hz) signal.

The contents of the IT2 flag can be loaded by software to

determine whether a 2 Hz timer interrupt has occured.

The flag is reset, when it is loaded by software. (See Figure

3.11.3.)

Address 0EFH

Address 0EBH

Timer interrupt

mask register (EIT)

Timer interrupt

factor flag (IT)

INT

(Interrupt request)

Interrupt flag (I)

Data bus

Data bus Basic clock counter

32 Hz

8 Hz

2 Hz

Fig. 3.11.3

Timer interrupt circuit

IT8

IT32

IT2

II-74 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Interrupt and Halt)

Address 0EAH

Stopwatch interrupt

mask register (EISW)

Stopwatch interrupt

factor flag (ISW)

INT

(Interrupt request)

Interrupt flag (I)

Data bus

Data bus Stopwatch

timer

10 Hz

1 Hz

Address 0EEH

This flag is set to "1" when a falling edge is detected in the

stopwatch timer (SWH, 1 Hz).

The contents of the ISW1 flag can be loaded by software to

determine whether a 1 Hz stopwatch interrupt has occured.

The flag is reset, when it is loaded by software. (See Figure

3.11.4.)

This flag is set to "1" when a falling edge is detected in the

stopwatch timer (SWH, 10 Hz).

The contents of the ISW0 flag can be loaded by software to

determine whether a 10 Hz stopwatch interrupt has oc-

cured.

The flag is reset, when it is loaded by software. (See Figure

3.11.4.)

The interrupt factor flags must always be loaded under the DI state

(interrupt flag [I] = "0"). Reading under the EI state (interrupt flag

[I] = "1") may cause an operation error.

Fig. 3.11.4

Stopwatch interrupt circuit

ISW1

ISW0

Note

S1C62N81 TECHNICAL SOFTWARE EPSON II-75

CHAPTER 3: PERIPHERAL CIRCUITS (Interrupt and Halt)

• Interrupt mask registers

The interrupt mask registers are registers that individually

specify whether to enable or mask the timer interrupt (2 Hz,

8 Hz, 32 Hz), stopwatch timer interrupt (1 Hz, 10 Hz), or

input interrupt (K00–K03, K10).

The following are descriptions of the interrupt mask regis-

ters.

This register enables or masks the K00–K03 input interrupt.

The interrupt condition flag (IK0) is set to "1" when the

contents of the input (K00–K03) and the interrupt differen-

tial register (KCP00–KCP03) do not match and the data of

the corresponding interrupt mask register (EIK00–EIK03) is

"1". The CPU is interrupted if it is in the EI state (interrupt

flag [I] = "1"). (See Figure 3.11.1.)

This register enables or masks the K10 input interrupt. The

interrupt condition flag (IK1) is set to "1" when the contents

of the input (K10) and the interrupt differential register

(KCP10) do not match and the data of the corresponding

interrupt mask register (EIK10) is "1". The CPU is inter-

rupted if it is in the EI state (interrupt flag [I] = "0"). (See

Figure 3.11.2.)

This register enables or masks the 32 Hz timer interrupt.

The CPU is interrupted if it is in the EI state when the

interrupt mask register (EIT32) is set to "1" and the inter-

rupt condition flag (IT32) is "1". (See Figure 3.11.3.)

EIK00 to EIK03

EIK10

EIT32

II-76 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Interrupt and Halt)

This register enables or masks the 8 Hz timer interrupt. The

CPU is interrupted if it is in the EI state when the interrupt

mask register (EIT8) is set to "1" and the interrupt condition

flag (IT8) is "1". (See Figure 3.11.3.)

This register enables or masks the 2 Hz timer interrupt. The

CPU is intterrupted if it is in the EI state when the interrupt

mask register (EIT2) is set to "1" and the interrupt condition

flag (IT2) is "1". (See Figure 3.11.3.)

This register enables or masks the 1 Hz stopwatch interrupt.

The CPU is interrupted if it is in the EI state when the

interrupt mask register (EISW1) is set to "1", and also the

interrupt condition flag (ISW1) is "1". (See Figure 3.11.4.)

This register enables or masks the 10 Hz stopwatch inter-

rupt. The CPU is interrupted if it is in the EI state when the

interrupt mask register (EISW0) is set to "1", and the inter-

rupt condition flag (ISW0) is "1". (See Figure 3.11.4.)

Write to the interrupt mask registers (EIT32, EIT8, EIT2) and read

the interrupt factor flags (IT32, IT8, IT2) in DI states only (interrupt

flag [I] = "0").

EISW1

EIT2

EIT8

Note

EISW0

S1C62N81 TECHNICAL SOFTWARE EPSON II-77

CHAPTER 3: PERIPHERAL CIRCUITS (Interrupt and Halt)

• Interrupt control registers

The data of the input comparison registers (KCP00–KCP03)

is compared with the data of the corresponding input ports

(K00–K03). If the data does not match and the correspond-

ing input mask register (EIK00–EIK03) is "1", the interrupt

factor flag (IK0) is set to "1".

These registers are used to determine the change in the

input (K01–K03) level. (See Figure 3.11.1.)

The data of the input comparison register (KCP10) is com-

pared with the data of the corresponding input port (K10). If

the data does not match and the corresponding input mask

"1".

This register is used to determine the change in the input

(K10) level. (See Figure 3.11.2.)

The input comparison register can effectively be used to

determine the on/off state of the input.

However, as shown in Figure 3.11.1, the result of compari-

son of the input (K00–K03) is collected in the interrupt

factor flag (IK0), so the input comparison register cannot be

used to determine the on/off state of the key matrix.

KCP00 to KCP03

KCP10

II-78 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Interrupt and Halt)

• Interrupt vector address

The S1C62N81 interrupt vector address is made up of the

low-order 4 bits of the program counter (12 bits), each of

which is assigned a specific function as shown in Table

3.11.2.

Table 3.11.2 Assignment of the interrupt vector address

As shown in Table 3.11.2, the lower order 4 bits of the

program counter are set according to which of the interrupts

occurs. In other words, the interrupt vector address is set

at page 1, steps 02H, 04H, 06H, 08H, 0AH.

Note that all of the three timer interrupts have the same

vector address, and software must be used to judge whether

or not a given timer interrupt has occurred. For instance,

when the 32 Hz timer interrupt and the 8 Hz timer interrupt

are enabled at the same time, the accepted timer interrupt

must be identified by software. (Similarly, the K00–K03

input interrupts and the 10 Hz/1 Hz stopwatch interrupts

must be identified by software.)

When an interrupt is generated, the hardware resets the

interrupt flag (I) to enter the DI state. Execute the EI in-

struction as necessary to recover the EI state after interrupt

processing.

PCP3 0

PCP2 0

PCP1 1

PCP0 0

PCS7 0

PCS6 0

PCS5 0

PCS4 1

PCS3 0

PCS2 1

PCS1 0

PCS0Interrupt Item

Melody

K10

K03–K00

Stopwatch

Timer

10A

108

106

104

102

Interrupt

Vector Address

Highest

Lowest

Priority

S1C62N81 TECHNICAL SOFTWARE EPSON II-79

CHAPTER 3: PERIPHERAL CIRCUITS (Interrupt and Halt)

Set the EI state at the start of the interrupt processing

routine to allow nesting of the interrupts. Then the priority

of the interrupt or the nesting level is determined and set by

hardware.

The interrupt factor flags must always be reset before set-

ting the EI status in the corresponding interrupt processing

routine. (The flag is reset when the interrupt condition flag

is read by software.)

If the EI instruction is executed without resetting the inter-

rupt factor flag after generating the timer interrupt or the

stopwatch timer interrupt or melody, and if the correspond-

ing interrupt mask register is still "1", the same interrupt is

generated once more. (See Figure 3.11.5.)

If the EI state is set without resetting the interrupt condition

flag after generating the input interrupt (K00–K03, K10), the

same interrupt is generated once more. (See Figure 3.11.5.)

The interrupt factor flag must always be read (reset) in the

DI state (interrupt flag [I] = "0"). There may be an operation

error if read in the EI state.

The timer interrupt factor flags (IT32, IT8, IT2) and the

stopwatch interrupt factor flags (ISW1, ISW0) are set

whether the corresponding interrupt mask register is set or

not.

The input interrupt factor flags (IK0, IK1) are allowed to be

set in the condition when the corresponding interrupt mask

enabled). (See Figure 3.11.5.)

II-80 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Interrupt and Halt)

IMEL

EIMEL

KCP10

EIK10

K10

KCP00

EIK00

K00

KCP01

EIK01

K01

KCP02

EIK02

K02

KCP03

EIK03

K03

ISW0

EISW0

ISW1

EISW1

IT2

EIT2

IT8

EIT8

IT32

EIT32

IK1

IK0

(MSB)

(LSB)

Program

counter

Interrupt vector

(low-order 4 bits)

Priority detection circuit

Fig. 3.11.5

Internal interrupt circuit

S1C62N81 TECHNICAL SOFTWARE EPSON II-81

CHAPTER 3: PERIPHERAL CIRCUITS (Interrupt and Halt)

• Restart from halt state by interrupt

Main routine

Label Mnemonic/operand Comment

LD X,0E8H ;Set address of K00 to K03

;interrupt mask register

OR MX,1111B ;Enable K00 to K03

;input interrupt

;LD X,0EAH ;Set address of stopwatch

;interrupt mask register

OR MX,0010B ;Enable 1 Hz stopwatch interrupt

;LD X,0EBH ;Set address of timer interrupt

;mask register

OR MX,0111B ;Enable timer interrupt

;(32 Hz, 8 Hz, 2 Hz)

LD X,E7H ;Set address of melody interrupt

;mask register

OR MX,0001B ;Enable melody interrupt

MAIN: EI ;Set interrupt flag (EI state is set)

HALT ;Halt mode

JP MAIN ;Jump to MAIN

Examples of interrupt

and halt control

program

II-82 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Interrupt and Halt)

Interruption vector routine

Label Mnemonic/operand Comment

ORG 100H

JP INIT ;Jump to initial routine

HALT

JP TIINT ;Jump to timer interrupt routine

HALT

JP SWINT ;Jump to stopwatch interrupt routine

HALT

JP K0INT ;Jump to K0 input interrupt routine

HALT

JP K1INT ;Jump to K1 input interrupt routine

HALT

JP MELINT ;Jump to melody interrupt routine

MELINT LD Y,0ECH ;Address of melody interrupt

;factor flag

LD A,MY ;Reset melody interrupt

;factor flag

RETURN EI

RET

K1INT LD Y,0EDH ;Address of K10 input port interrupt

;factor flag

LD A,MY ;Reset K10 input port interrupt

;factor flag

JP RETURN

K0INT LD Y,0EDH ;Address of K0n input port interrupt

;factor flag

LD A,MY ;Reset K0n input port interrupt

;factor flag

JP RETURN

SWINT LD Y,0EEH ;Address of stopwatch interrupt

;factor flag

LD X,SWFSTK ;Address of stopwatch interrupt

;factor flag buffer

LD MX,MY ;Store stopwatch interrupt

;factor flag in buffer

FAN MX,0010B ;Check stopwatch 1 Hz

;factor flag

JP Z,SW10RQ ;Jump if not the 1 Hz request

;interrupt

CALL SW1IN ;Stopwatch 1 Hz interrupt

;service routine

SW10RQ LD X,SWFSTK ;Address of stopwatch interrupt

;factor flag buffer

S1C62N81 TECHNICAL SOFTWARE EPSON II-83

CHAPTER 3: PERIPHERAL CIRCUITS (Interrupt and Halt)

FAN MX,0001B ;Check stopwatch 10 Hz

;factor flag

JP Z,RETURN ;Return

CALL SW10IN ;Stopwatch 10 Hz interrupt

;service routine

JP RETURN

TIINT LD Y,0EFH ;Address of timer interrupt

;factor flag

LD X,TMFSK ;Address of timer interrupt

;factor flag buffer

LD MX,MY ;Store timer interrupt factor

;flag in buffer

FAN MX,0100B ;Check 2 Hz timer interrupt

;factor flag

CALL TINT2 ;Call 2 Hz timer interrupt

;service routine

JP RETURN ;Return

TI8RQ LD X,TMFSK ;Address of timer interrupt factor

;flag buffer

FAN MX,0010B ;Check 8 Hz timer interrupt

;factor flag

JP Z,TI32RQ ;Don't request interrupt

CALL TINT8 ;Call 8 Hz timer interrupt

;service routine

TI32RQ LD X,TMFSK ;Address of timer interrupt factor

;flag buffer

FAN MX,0001B ;Check 32 Hz timer interrupt

;factor flag

JP Z,RETURN ;Don't request interrupt

CALL TINT32 ;Call 32 Hz timer interrupt

;service routine

JP RETURN

The above program is normally used to restart the CPU

when in the halt state by interrupt and to return it to the

halt state again after the interrupt processing is completed.

The processing proceeds by repeating the → halt interrupt

→ halt → interrupt cycle.

II-84 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 3: PERIPHERAL CIRCUITS (Interrupt and Halt)

All interrupts are enabled, and the priority when all inter-

rupts are generated simultaneously is determined by hard-

ware as follows:

(highest priority) Melody interrupt → K10 interrupt → K00–

K03 interrupt → stopwatch interrupt → timer interrupt

(lowest priority)

The two stopwatch interrupts (1 Hz, 10 Hz) have the same

vector address (104H). The priority is decided by software;

the stopwatch interrupt service routine first checks the 1 Hz

interrupt factor flag, so the priority is (high priority) stop-

watch 1 Hz interrupt → stopwatch 10 Hz interrupt (low

priority).

The three timer interrupts (2 Hz, 8 Hz, 32 Hz) have the same

vector address (102H). The priority is decided by software;

the timer interrupt service routine first checks the 2 Hz

interrupt factor flag, then 8 Hz, and finally 32 Hz, so the

priority is (first priority) timer 2 Hz interrupt → (second

priority) timer 8 Hz interrupt → (third priority) timer 32 Hz

interrupt.

Always load (reset) the interrupt factor flags in the DI state

(interrupt flag [I] = "0"). There may be an operation error if

loaded in the EI state.

S1C62N81 TECHNICAL SOFTWARE EPSON II-85

CHAPTER 4: SUMMARY OF PROGRAMMING POINTS

CHAPTER 4 SUMMARY OF PROGRAMMING

POINTS

• Core CPU After the system reset, only the program counter (PC),

new page pointer (NPP) and interrupt flag (I) are initial-

ized by the hardware. The other internal circuits whose

settings are undefined must be initialized with the pro-

gram.

• Memory Memory is not mounted in unused area within the mem-

ory map and in memory area not indicated in this man-

ual. For this reason, normal operation cannot be assured

for programs that have been prepared with access to

these areas.

• Input Port When modifying the input port from high level to low level

with pull-down resistance, a delay will occur at the rise of

the waveform due to time constant of the pull-down

resistance and input gate capacities. Provide appropriate

waiting time in the program when performing input port

reading.

• LCD Driver – Because the display memory is for writing only, re-writing

the contents with computing instructions (e.G., AND, OR,

etc.) which come with read-out operations is not possible.

To perform bit operations, a buffer to hold the display

data is required on the RAM.

– Even when 1/3 duty is selected, the display data corre-

sponding to COM3 is valid for static drive. Hence, for

static drive set the same value to all display memory

corresponding COM0–COM3.

– For cadence adjustment, set the display data including

display data corresponding to COM3.

– fosc indicates the oscillation frequency of the oscillation

circuit.

II-86 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 4: SUMMARY OF PROGRAMMING POINTS

• Interrupt – Even when the contents of the input data and input

comparator register change from an unmatched state to

another unmatched state or to a matched state, no

interrupt will occur.

– Re-start from the HALT state is performed by the inter-

rupt. The return address after completion of the interrupt

processing in this case will be the address following the

HALT instruction.

– When interrupt occurs, the interrupt flag will be reset by

the hardware and it will become DI state. After comple-

tion of the interrupt processing, set to the EI state

through the software as needed.

Moreover, the nesting level may be set to be program-

mable by setting to the EI state at the beginning of the

interrupt processing routine.

– Be sure to reset the interrupt factor flag before setting to

the EI state on the interrupt processing routine. The

interrupt factor flag is reset by reading through the

software. Not resetting the interrupt factor flag and

interrupt mask register being "1", will cause the same

interrupt to occur again.

– The interrupt factor flag will be reset by reading through

the software. Because of this, when multiple interrupt

factor flags are to be assigned to the same address,

perform the flag check after the contents of the address

has been stored in the RAM. Direct checking with the

FAN instruction will cause all the interrupt factor flag to

be reset.

– Be sure to perform the interrupt factor flag reading while

in the DI (interrupt flag = "0") state. Performing the read-

ing while in the EI (interrupt flag = "1") state may cause

mis-operation.

– Be sure to perform the interrupt mask register writing

while in the DI (interrupt flag = "0") state. Writing while in

the EI (interrupt flag = "1") state may cause mis-opera-

tion.

– In case multiple interrupts occur simultaneously, inter-

rupt processing will be done in the order of high priority

first.

S1C62N81 TECHNICAL SOFTWARE EPSON II-87

CHAPTER 4: SUMMARY OF PROGRAMMING POINTS

• Power Supply External load driving through the output voltage of con-

stant voltage circuit or booster circuit is not permitted.

• Initial Reset When utilizing the simultaneous high input reset func-

tion of the input ports (K00–K03), take care not to make

the ports specified during normal operation to go high

simultaneously.

• Data Memory – Since some portions of the RAM are also used as stack

area during sub-routine call or register saving, see to it

that the data area and the stack area do not overlap.

– The stack area consumes 3 words during a sub-routine

call or interrupt.

– Address 00H–0FH in the RAM is the memory register area

addressed by the register pointer RP.

• Output Port The FOUT output signal may produce hazards when the

output port R10 is turned on or off.

• I/O Port – When the I/O port is set to the output mode and a low-

impedance load is connected to the port pin, the data

written to the register may differ from the data read.

– When the I/O port is set to the input mode and a low-

level voltage (VSS) is input by the built-in pull-down

resistance, an erroneous input results if the time con-

stant of the capacitive load of the input line and the built-

in pull-down resistance load is greater than the read-out

time. When the input data is being read, the time that the

input line is pulled down is equivalent to 0.5 cycles of the

CPU system clock.

Hence, the electric potential of the pins must settle within

0.5 cycles. If this condition cannot be met, some measure

must be devised, such as arranging a pull-down resis-

tance externally, or performing multiple read-outs.

• Analog Comparator Data in the CMPDT register becomes "1" when CMPON is

"0" (analog comparator circuit is off), and undefined when

the CMPP and/or CMPM input is disconnected. Avoid

reading operation under those conditions.

II-88 EPSON S1C62N81 TECHNICAL SOFTWARE

CHAPTER 4: SUMMARY OF PROGRAMMING POINTS

• Vacant Register and

Read/Write Writing data into the addresses where read/write bits

and read only bits are mixed in 1 word (4 bits) does not

affect the read only bits.

• Battery Voltage Low

Detection (BLD)

Circuit

Since battery voltage low detection is automatically

performed by the hardware every 2 Hz (0.5 second) when

the heavy load protection function operates, do not per-

mit the operation of the BLD circuit by the software in

order to minimize power current consumption.

• Heavy Load Protec-

tion Function In the heavy load protection function (heavy load protec-

tion mode flag = "1"), battery voltage low detection

through the BLDON register is not permitted in order to

minimize power current consumption.

S1C62N81 TECHNICAL SOFTWARE EPSON II-89

APPENDIX A: TABLE OF INSTRUCTIONS

APPENDIX A Table of Instructions

C, s

NC, s

Z, s

NZ, s

X, x

Y, y

XH, r

XL, r

YH, r

YL, r

r, XH

r, XL

r, YH

r, YL

XH, i

XL, i

YH, i

YL, i

PSET

JPBA

CALL

CALZ

RET

RETS

RETD

NOP5

NOP7

HALT

INC

ADC

Branch

instructions

System

control

instructions

Index

operation

instructions

Classification Operand

IDZC

↑

Clock

Operation Code Flag

NBP p4, NPP p3~p0

PCB NBP, PCP NPP, PCS s7~s0

PCB NBP, PCP NPP, PCS s7~s0 if C=1

PCB NBP, PCP NPP, PCS s7~s0 if C=0

PCB NBP, PCP NPP, PCS s7~s0 if Z=1

PCB NBP, PCP NPP, PCS s7~s0 if Z=0

←

←←

←

PCB NBP, PCP NPP, PCSH B, PCSL A

M(SP-1) PCP, M(SP-2) PCSH, M(SP-3) PCSL+1

SP SP-3, PCP NPP, PCS s7~s0

M(SP-1) PCP, M(SP-2) PCSH, M(SP-3) PCSL+1

SP SP-3, PCP 0, PCS s7~s0

PCSL M(SP), PCSH M(SP+1), PCP M(SP+2)

SP SP+3

PCSL M(SP), PCSH M(SP+1), PCP M(SP+2)

SP SP+3, PC PC+1

PCSL M(SP), PCSH M(SP+1), PCP M(SP+2)

SP SP+3, M(X) i3~i0, M(X+1) l7~l4, X X+2

No operation (5 clock cycles)

No operation (7 clock cycles)

Halt (stop clock)

X X+1

Y Y+1

XH x7~x4, XL x3~x0

YH y7~y4, YL y3~y0

r XH

r XL

r YH

r YL

←←

←←←

←←← ←←←

←←←

←←← ←

←← ←← ←

←←←←

←

←←

←

←←

←

Mne-

monic Operation

XH+i3~i0+C

XL+i3~i0+C

YH+i3~i0+C

YL+i3~i0+C

↓

II-90 EPSON S1C62N81 TECHNICAL SOFTWARE

APPENDIX A: TABLE OF INSTRUCTIONS

XH, i

XL, i

YH, i

YL, i

r, i

r, q

A, Mn

B, Mn

Mn, A

Mn, B

MX, i

r, q

MY, i

r, q

MX, l

F, i

LDPX

LDPY

LBPX

SET

RST

SCF

RCF

SZF

RZF

SDF

RDF

INC

DEC

PUSH

POP

Index

operation

instructions

Data

transfer

instructions

Flag

operation

instructions

Stack

operation

instructions

Classification Operand

IDZC

↑

↓

↑

↓

↑

↓

↑

↓

↑

↓

↑

↓

Clock

Operation Code Flag

XH-i3~i0

XL-i3~i0

YH-i3~i0

YL-i3~i0

r i3~i0

r q

M(n3~n0) A

M(n3~n0) B

M(X) i3~i0, X X+1

r q, X X+1

M(Y) i3~i0, Y Y+1

r q, Y Y+1

M(X) l3~l0, M(X+1) l7~l4, X X+2

←

←←

←

←← ←←

Mne-

monic Operation

↓

↑

↓

↑

↓

SP SP+1

SP SP-1

SP SP-1, M(SP) r

SP SP-1, M(SP) XH

SP SP-1, M(SP) XL

SP SP-1, M(SP) YH

SP SP-1, M(SP) YL

SP SP-1, M(SP) F

r M(SP), SP SP+1

←

M(n3~n0)

←

←←

←

F i3~i0

1 (Decimal Adjuster ON)

0 (Decimal Adjuster OFF)

1 (Enables Interrupt)

0 (Disables Interrupt)

←

←←

←

M(SP), SP SP+1

←

S1C62N81 TECHNICAL SOFTWARE EPSON II-91

APPENDIX A: TABLE OF INSTRUCTIONS

d3 d2, d2 d1, d1 d0, d0 C, C d3

d3 C, d2 d3, d1 d2, d0 d1, C d0

M(n3~n0) M(n3~n0)+1

M(n3~n0) M(n3~n0)-1

↓

SPH, r

SPL, r

r, SPH

r, SPL

r, i

r, q

r, i

r, q

r, i

r, q

r, i

r, q

r, i

r, q

r, i

r, q

r, i

r, q

r, i

r, q

MX, r

MY, r

MX, r

MY, r

POP

ADD

ADC

SUB

SBC

AND

XOR

FAN

RLC

RRC

INC

DEC

ACPX

ACPY

SCPX

SCPY

NOT

Stack

operation

instructions

Arithmetic

instructions

Classification Operand

IDZC

↑↑

↑

Clock

Operation Code Flag

F M(SP), SP SP+1

SPH

SPL

r SPH

r SPL

←

Mne-

monic Operation

↓

↑

←

↓↓

★

r r+i3~i0

r r+q

r r+i3~i0+C

r r+q+C

r r-q

r r-i3~i0-C

r r-q-C

r r i3~i0

r r q

r r i3~i0

r r q

r r i3~i0

r r q

r-i3~i0

r-q

r i3~i0

r q

M(X) M(X)+r+C, X X+1

M(Y) M(Y)+r+C, Y Y+1

M(X) M(X)-r-C, X X+1

M(Y) M(Y)-r-C, Y Y+1

r r

M(SP), SP SP+1

←

←←

←

←←← ←

←← ← ←←

←

II-92 EPSON S1C62N81 TECHNICAL SOFTWARE

APPENDIX A: TABLE OF INSTRUCTIONS

Abbreviations used in the explanations have the following

meanings.

A .............. A register

B .............. B register

X .............. XHL register (low order eight bits of index register

IX)

Y .............. YHL register (low order eight bits of index

XH ........... XH register (high order four bits of XHL register)

XL ............ XL register (low order four bits of XHL register)

YH............ YH register (high order four bits of YHL register)

YL ............ YL register (low order four bits of YHL register)

XP ............ XP register (high order four bits of index

YP ............ YP register (high order four bits of index

SP ............ Stack pointer SP

SPH.......... High-order four bits of stack pointer SP

SPL .......... Low-order four bits of stack pointer SP

MX, M(X) .. Data memory whose address is specified with

index register IX

MY, M(Y)... Data memory whose address is specified with

index register IY

Mn, M(n) .. Data memory address 000H–00FH (address

specified with immediate data n of 00H–0FH)

M(SP) ....... Data memory whose address is specified with

stack pointer SP

r, q ........... Two-bit register code

r, q is two-bit immediate data; according to the

contents of these bits, they indicate registers A,

B, and MX and MY (data memory whose ad-

dresses are specified with index registers IX and

IY) rq

r1 r0 q1 q0

0000 A

0101 B

1010 MX

1111 MY

Registers specified

Symbols associated with

registers and memory

S1C62N81 TECHNICAL SOFTWARE EPSON II-93

APPENDIX A: TABLE OF INSTRUCTIONS

NBP..... New bank pointer

NPP ..... New page pointer

PCB..... Program counter bank

PCP ..... Program counter page

PCS ..... Program counter step

PCSH .. Four high order bits of PCS

PCSL ... Four low order bits of PCS

F ......... Flag register (I, D, Z, C)

C ......... Carry flag

Z ......... Zero flag

D......... Decimal flag

I .......... Interrupt flag

↓............. Flag reset

↑............. Flag set

↕......... Flag set or reset

p ......... Five-bit immediate data or label 00H–1FH

s.......... Eight-bit immediate data or label 00H–0FFH

l .......... Eight-bit immediate data 00H–0FFH

i .......... Four-bit immediate data 00H–0FH

+ ......... Add

- .......... Subtract

∧............. Logical AND

∨............. Logical OR

∀ ............ Exclusive-OR

★........ Add-subtract instruction for decimal operation

when the D flag is set

Symbols associated with

program counter

Symbols associated with

flags

Associated with

immediate data

Associated with

arithmetic and other

operations

II-94 EPSON S1C62N81 TECHNICAL SOFTWARE

APPENDIX B: THE S1C62N81 I/O MEMORY MAP

APPENDIX B The S1C62N81 I/O Memory Map

K03

K02

K01

K00

–

HIGH

LOW

INPORT DATA K03

INPORT DATA K02

INPORT DATA K01

INPORT DATA K00

K00

K01

K02

K03

K10

–

HIGH

–

LOW INPORT DATA K10

K10

SWL3

SWL2

SWL1

SWL0

–

STOPWATCH TIMER DATA 3 (1/100) MSB

STOPWATCH TIMER DATA 2 (1/100)

STOPWATCH TIMER DATA 1 (1/100)

STOPWATCH TIMER DATA 0 (1/100) LSB

SWL0

SWL1

SWL2

SWL3

SWH3

SWH2

SWH1

SWH0

–

STOPWATCH TIMER DATA 3 (1/10) MSB

STOPWATCH TIMER DATA 2 (1/10)

STOPWATCH TIMER DATA 1 (1/10)

STOPWATCH TIMER DATA 0 (1/10) LSB

SWH0

SWH1

SWH2

SWH3

TM3

TM2

TM1

TM0

HIGH

LOW

CLOCK TIMER DATA 2Hz

CLOCK TIMER DATA 4Hz

CLOCK TIMER DATA 8Hz

CLOCK TIMER DATA 16Hz

TM0

TM1

TM2

TM3

KCP03

KCP02

KCP01

KCP00

FALLING

RISING

K03 INPUT COMPARISON REGISTER

K02 INPUT COMPARISON REGISTER

K01 INPUT COMPARISON REGISTER

K00 INPUT COMPARISON REGISTER

KCP00

R/W

KCP01

R/W

KCP02

R/W

KCP03

R/W

KCP10

–

FALLING

–

RISING K10 INPUT COMPARISON REGISTER

KCP10

R/W

EIMEL

–

ENABLE

–

MASK MELODY INTERRUPT MASK REGISTER

EIMEL

R/W

EIK03

EIK02

EIK01

EIK00

ENABLE

MASK

K03 INTERRUPT MASK REGISTER

K02 INTERRUPT MASK REGISTER

K01 INTERRUPT MASK REGISTER

K00 INTERRUPT MASK REGISTER

EIK00

R/W

EIK01

R/W

EIK02

R/W

EIK03

R/W

EIK10

–

ENABLE MASK K10 INTERRUPT MASK REGISTER

EIK10

R/W

EISW1

EISW0

–

ENABLE

–

MASK

MASK S/W INTERRUPT MASK REGISTER 1Hz

S/W INTERRUPT MASK REGISTER 10Hz

EISW0

R/W

EISW1

R/W

EIT2

EIT8

EIT32

–

ENABLE

–

MASK

TIMER INTERRUPT MASK REGISTER 2Hz

TIMER INTERRUPT MASK REGISTER 8Hz

TIMER INTERRUPT MASK REGISTER 32Hz

EIT32

R/W

EIT8

R/W

EIT2

R/W

IMEL

–

YES

–

NO MELODY INTERRUPT FACTOR FLAG

IMEL

IK1

IK0

–

YES

–

NO K10 INTERRUPT FACTOR FLAG

K00–K03 INTERRUPT FACTOR FLAG

IK0

IK1

ISW1

ISW0

–

YES

–

NO S/W INTERRUPT FACTOR FLAG 1Hz

S/W INTERRUPT FACTOR FLAG 10Hz

ISW0

ISW1

IT2

IT8

IT32

–

YES

–

TIMER INTERRUPT FACTOR FLAG 2Hz

TIMER INTERRUPT FACTOR FLAG 8Hz

TIMER INTERRUPT FACTOR FLAG 32Hz

IT32

IT8

IT2

AD-

DRESS

D0D1D2D3 01SRNAME COMMENT

DATA

S1C62N81 TECHNICAL SOFTWARE EPSON II-95

APPENDIX B: THE S1C62N81 I/O MEMORY MAP

MAD3

MAD2

MAD1

MAD0

HIGH

LOW

MEL. ROM ADDR. SETTING REG. AD3

MEL. ROM ADDR. SETTING REG. AD2

MEL. ROM ADDR. SETTING REG. AD1

MEL. ROM ADDR. SETTING REG. LSB

MAD0

R/W

MAD1

R/W

MAD2

R/W

MAD3

R/W

MAD6

MAD5

MAD4

–

HIGH

–

LOW

MEL. ROM ADDR. SETTING REG. MSB

MEL. ROM ADDR. SETTING REG. AD5

MEL. ROM ADDR. SETTING REG. AD4

MAD4

R/W

MAD5

R/W

MAD6

R/W

CLK1

CLK0

TEMPC

MELC

HIGH

LOW

OFF

REG. TO CHANGE MELODY CLOCK

REG. TO CHANGE TWO KINDS OF TEMPO

MELODY ON/OFF CONTROL REGISTER

MELC

R/W

TEMPC

R/W

CLKC0

R/W

CLKC1

R/W

R03

R02

R01

R00

HIGH

LOW

R03 OUT PORT DATA

R02 OUT PORT DATA

R01 OUT PORT DATA

R00 OUT PORT DATA

R00

R/W

R01

R/W

R02

R/W

R03

R/W

R12

ENV

R11

R10

FOUT

HIGH

–

HIGH

LOW

–

LOW

OFF

R12 OUT PORT DATA

MELODY INVERTED OUTPUT

MELODY ENVELOPE CONTROL

R11 OUT PORT DATA

R10 OUT PORT DATA

FREQUENCY OUTPUT

R10

FOUT

R/W

R11

R/W

R12

ENV

R/W

–

R/W

–

P03

P02

P01

P00

–

HIGH

LOW

P03 I/O PORT DATA

P02 I/O PORT DATA

P01 I/O PORT DATA

P00 I/O PORT DATA

P00

R/W

P01

R/W

P02

R/W

P03

R/W

–

TMRST

SWRUN

SWRST

–

RESET

–

RESET

RUN

RESET

–

STOP

–

TIMER RESET

STOPWATCH RUN/STOP CONTROL REG.

STOPWATCH RESET

SWRST

SWRUN

R/W

TMRST

HLMOD

BLDDT

BLDON

–

HEAVY

–

LOW

NORMAL

–

NORMAL

OFF

HEAVY LOAD PROTECTION MODE

BLD DATA

BLD ON-OFF CONTROL REGISTER

BLDON

R/W

BLDDT

HLMOD

R/W

CSDC

CMPDT

CMPON

–

STATIC

–

+>-

DYNAMIC

–

->+

OFF

LCD DRIVER CONTROL REG.

CMP DATA

COMPARATOR ON-OFF CONTROL REG.

CMPON

R/W

CMPDT

CSDC

R/W

IOC

–

OUT

–

IN I/O IN-OUT CONTROL REG.

IOC

R/W

AD-

DRESS

D0D1D2D3 01SRNAME COMMENT

DATA

II-96 EPSON S1C62N81 TECHNICAL SOFTWARE

APPENDIX C: TABLE OF THE ICE COMMANDS

APPENDIX C Table of the ICE Commands

Assemble

Disassemble

Dump

Fill

Set

Run Mode

Trace

Break

Move

Data Set

Change CPU

Internal

Registers

#A,a

#L,a1,a2

#DP,a1,a2

#DD,a1,a2

#FP,a1,a2,d

#FD,a1,a2,d

#G,a

#TIM

#OTF

#T,a,n

#U,a,n

#BA,a

#BAR,a

#BD

#BDR

#BR

#BRR

#BM

#BMR

#BRES

#BC

#BE

#BSYN

#BT

#BRKSEL,REM

#MP,a1,a2,a3

#MD,a1,a2,a3

#SP,a

#SD,a

#DR

#SR

#DXY

#SXY

Assemble command mnemonic code and store at address "a"

Contents of addresses a1 to a2 are disassembled and displayed

Contents of program area a1 to a2 are displayed

Content of data area a1 to a2 are displayed

Data d is set in addresses a1 to a2 (program area)

Data d is set in addresses a1 to a2 (data area)

Program is executed from the "a" address

Execution time and step counter selection

On-the-fly display selection

Executes program while displaying results of step instruction

from "a" address

Displays only the final step of #T,a,n

Sets Break at program address "a"

Breakpoint is canceled

Break condition is set for data RAM

Breakpoint is canceled

Break condition is set for Evaluation Board CPU internal registers

Breakpoint is canceled

Combined break conditions set for program data RAM address

and registers

Cancel combined break conditions for program data ROM

address and registers

All break conditions canceled

Break condition displayed

Enter break enable mode

Enter break disable mode

Set break stop/trace modes

Set BA condition clear/remain modes

Contents of program area addresses a1 to a2 are moved to

addresses a3 and after

Contents of data area addresses a1 to a2 are moved to addresses

a3 and after

Data from program area address "a" are written to memory

Data from data area address "a" are written to memory

Item No. Function Command Format Outline of Operation

Display Evaluation Board CPU internal registers

Set Evaluation Board CPU internal registers

Reset Evaluation Board CPU

Display X, Y, MX and MY

Set data for X and Y display and MX, MY

S1C62N81 TECHNICAL SOFTWARE EPSON II-97

APPENDIX C: TABLE OF THE ICE COMMANDS

History

File

Coverage

ROM Access

Terminate

ICE

Command

Display

Self

Diagnosis

#H,p1,p2

#HB

#HG

#HP

#HPS,a

#HC,S/C/E

#HA,a1,a2

#HAR,a1,a2

#HAD

#HS,a

#HSW,a

#HSR,a

#RF,file

#RFD,file

#VF,file

#VFD,file

#WF,file

#WFD,file

#CL,file

#CS,file

#OPTLD,n,file

#CVD

#CVR

#RP

#VP

#ROM

#HELP

#CHK

Display history data for pointer 1 and pointer 2

Display upstream history data

Display 21 line history data

Display history pointer

Set history pointer

Sets up the history information acquisition before (S),

before/after (C) and after (E)

Sets up the history information acquisition from program area

a1 to a2

Sets up the prohibition of the history information acquisition

from program area a1 to a2

Indicates history acquisition program area

Retrieves and indicates the history information which executed

a program address "a"

Retrieves and indicates the history information which wrote or

read the data area address "a"

Save contents of memory to program file

Save contents of memory to data file

Load ICE set condition from file

Save ICE set condition to file

Load HEXA data flom file

Terminate ICE and return to operating system control

Display ICE instruction

Report results of ICE self diagnostic test

Move program file to memory

Move data file to memory

Compare program file and contents of memory

Compare data file and contents of memory

Indicates coverage information

Clears coverage information

Move contents of ROM to program memory

Compare contents of ROM with contents of program memory

Set ROM type

Item No. Function Command Format Outline of Operation

means press the RETURN key.

II-98 EPSON S1C62N81 TECHNICAL SOFTWARE

APPENDIX D: CROSS-ASSEMBLER PSEUDO INSTRUCTION LIST

APPENDIX D Cross-assembler Pseudo Instruction List

Item No. Pseudo-instruction Meaning Example of Use

EQU

(Equation)

ORG

(Origin)

SET

(Set)

(Define Word)

PAGE

(Page)

SECTION

(Section)

END

(End)

MACRO

(Macro)

LOCAL

(Local)

ENDM

(End Macro)

To allocate data to label

To define location counter

To allocate data to label

(data can be changed)

To define ROM data

To define boundary of page

To define boundary of section

To terminate assembly

To define macro

To make local specification of label

during macro definition

To end macro definition

ABC EQU 9

CHECK MACRO DATA

LOCAL LOOP

LOOP CP MX,DATA

JP NZ,LOOP

ENDM

CHECK 1

BCD EQU ABC+1

ORG 100H

ORG 256

ABC SET 0001H

ABC SET 0002H

ABC DW 'AB'

BCD DW 0FFBH

PAGE 1H

PAGE 15

SECTION

END

S1C62N81 TECHNICAL SOFTWARE EPSON II-99

APPENDIX E: THE FORMAT OF MELODY SOURCE FILE

Contents of the source file, created with an editor such as

EDLIN, are configured from the S1C62N81 Series melody

codes and the pseudo-instructions described later.

Source File Name

The source file can be named with a maximum of any seven

characters. As a rule, keep to the following format.

C281YYY.MDT

Three alphanumerics are entered in the "YYY" part. Refer to

the model name from Seiko Epson. The extension must be

".MDT".

Statement (line)

Write each of the source file statements (lines) as follows:

APPENDIX E The Format of Melody Source File

Basic format:

Example: <attack> <note> <scale> <end bit> <comment>

.TEMPC0=5

.TEMPC1=8

.OCTAVE=32

;

ORG

;

10H

E4#

G5#

A4#

C3#

$45

$E3

$97

A5#

$42

;1st Melody

;2nd Melody

Attack field Note field Scale field End bit field Comment field

II-100 EPSON S1C62N81 TECHNICAL SOFTWARE

APPENDIX E: THE FORMAT OF MELODY SOURCE FILE

The statement is made up of the five fields: attack field, note

field, scale field, end bit field, and comment field. Up to 80

characters can be written in the statement. The fields are

separated by one or more spaces or by inserting tabs.

The end bit fields and comment fields can be filled in on an

as-needed basis.

A blank line is also permitted for the CR (carriage return)

code only. However, it is not permitted on the last line. Each

of the fields can be started from any column.

Control of the attack output is written.

When "1" is written, attack output is performed. When "0"

is written, attack output is not performed.

Eight notes can be specified with the melody ROM codes D5

through D7. Fill in the note field with numbers from 1 to 8.

The scale field can be filled in with any scale data (C3

through C6#).

When inputting the code directly, prefix the code with "$". In

this case, the input code range is 00H through FDH.

The instruction indicating the end of the melody is written

in the end bit field. When "1" is written, the melody finishes

with the melody ROM code of that address. Otherwise, write

"0", or omit it altogether.

Any comment, such as the program index or processing

details, can be written in the comment field, with no affect

on the object file created with the assembler.

The comment field is the area between the semicolon ";" and

the CR code at the end of the line.

A line can be made up of a comment field alone. However, if

the comment extends into two or more lines, each line must

be headed with a semicolon.

Scale field

Attack field

Note field

No.

Note

12345678

End bit field

Comment field

S1C62N81 TECHNICAL SOFTWARE EPSON II-101

APPENDIX F: DIVIDING TABLE

APPENDIX F Dividing Table

Dividing table at no use of octave 32.768 kHz

Scale

Data Scale ROM Code

Hex.

Frequency

(Hz) Dividing

Ratio Absolute

Error (%) Standard

Frequency (Hz)

C3#

D3#

F3#

G3#

A3#

C4#

D4#

F4#

G4#

A4#

C5#

D5#

F5#

G5#

A5#

C6#

128

135.405

143.719

152.409

161.419

170.667

181.039

191.626

203.528

215.579

227.556

240.941

256

270.810

287.439

303.407

321.255

341.333

360.088

385.506

404.543

431.158

455.111

481.882

512

546.133

574.877

606.815

642.510

682.667

728.178

762.047

819.200

862.316

910.222

963.765

1024

1092.267

1/128

1/121

1/114

1/107

1/101

1/96

1/90

1/85

1/80

1/76

1/72

1/68

1/64

1/60

1/57

1/54

1/51

1/48

1/45

1/42

1/40

1/38

1/36

1/34

1/32

1/30

1/28

1/27

1/25

1/24

1/22

1/21

1/20

1/19

1/18

1/17

1/16

1/15

1/2

103

102

1/2

-0.152

0.031

0.024

0.092

-0.113

0.010

-0.030

0.167

0.143

-0.226

-0.287

-0.153

0.031

-0.339

-0.400

-0.113

-0.542

0.503

-0.453

0.144

-0.226

-0.287

0.675

0.031

-0.339

-0.400

-0.113

0.563

-0.668

0.787

0.144

-0.226

-0.287

0.675

128

135.611

143.675

152.218

161.270

170.860

181.019

191.783

203.187

215.270

228.070

241.632

256

271.222

287.350

304.436

322.540

341.720

362.038

383.566

406.374

430.540

456.140

483.264

512

542.444

574.700

608.872

645.080

683.440

724.076

767.132

812.748

861.080

912.280

966.528

1024

1084.888

II-102 EPSON S1C62N81 TECHNICAL SOFTWARE

APPENDIX F: DIVIDING TABLE

Scale

Data Scale ROM Code

Hex.

Frequency

(Hz) Dividing

Ratio Absolute

Error (%) Standard

Frequency (Hz)

C4#

D4#

F4#

G4#

A4#

C5#

D5#

F5#

G5#

A5#

C6#

D6#

F6#

G6#

A6#

C7#

256

270.810

287.439

304.819

322.837

341.333

362.077

383.251

407.056

431.158

455.111

481.882

512

541.620

574.877

606.815

642.510

682.667

720.176

771.012

809.086

862.316

910.222

963.765

1024

1092.267

1149.754

1213.630

1285.020

1365.333

1456.356

1524.093

1638.400

1724.632

1820.444

1927.529

2048

2194.533

1/128

1/121

1/114

1/107

1/101

1/96

1/90

1/85

1/80

1/76

1/72

1/68

1/64

1/60

1/57

1/54

1/51

1/48

1/45

1/42

1/40

1/38

1/36

1/34

1/32

1/30

1/28

1/27

1/25

1/24

1/22

1/21

1/20

1/19

1/18

1/17

1/16

1/15

1/2

103

102

1/2

-0.152

0.031

2.448

0.092

-0.113

0.011

-0.082

0.168

0.143

-0.226

-0.287

-0.152

0.031

-0.339

-0.400

-0.113

-0.541

0.503

-0.453

0.143

-0.226

-0.287

0.676

0.031

-0.339

-0.399

-0.113

0.563

-0.667

0.788

0.143

-0.226

-0.287

0.676

256

271.222

287.350

304.436

322.540

341.720

362.038

383.566

406.374

430.540

456.140

483.264

512

542.444

574.700

608.872

645.080

683.440

724.076

767.132

812.748

861.080

912.280

966.528

1024

1084.888

1149.400

1217.748

1290.160

1366.880

1448.152

1534.264

1625.496

1722.160

1824.560

1933.056

2048

2169.776

Dividing table at no use of octave 65.536 kHz

S1C62N81 TECHNICAL SOFTWARE EPSON II-103

APPENDIX G: RAM MAP

APPENDIX G RAM Map

PROGRAM NAME: C281_____ /

MAME

MSB

LSB

MAME

MSB

LSB

MAME

MSB

LSB

MAME

MSB

LSB

MAME

MSB

LSB

MAME

MSB

LSB

0123456789ABCDEF

II-104 EPSON S1C62N81 TECHNICAL SOFTWARE

APPENDIX G: RAM MAP

PROGRAM NAME: C281_____ /

MAME

MSB

LSB

MAME

MSB

LSB

MAME

MSB

LSB

MAME

MSB

LSB

0123456789ABCDEF

—

ZK00

ZK01

ZK02

ZK03

—

ZMAD0

ZMAD1

ZMAD2

ZMAD3

—

ZK10

—

ZMAD4

ZMAD5

ZMAD6

—

ZSWL0

ZSWL1

ZSWL2

ZSWL3

—

ZMELC

ZTEMPC

ZCLKC0

ZCLKC1

—

ZSWH0

ZSWH1

ZSWH2

ZSWH3

—

ZR00

ZR01

ZR02

ZR03

—

ZTM0

ZTM1

ZTM2

ZTM3

—

ZFOUT

ZR11

ZR12

—

ZKCP00

ZKCP01

ZKCP02

ZKCP03

—

ZKCP10

—

ZP00

ZP01

ZP02

ZP03

—

ZEIMEL

—

ZEIK00

ZEIK01

ZEIK02

ZEIK03

—

ZEIK10

—

ZSWRST

ZSWRUN

ZTMRST

—

ZEISW0

ZEISW1

—

ZBLDON

ZBLDDT

—

ZHLMOD

—

ZEIT32

ZEIT8

ZEIT2

—

ZCMPON

ZCMPDT

—

ZCSDC

—

ZIMEL

—

ZIOC

—

ZIK0

ZIK1

—

ZISW0

ZISW1

—

ZIT32

ZIT8

ZIT2

—

AMERICA

EPSON ELECTRONICS AMERICA, INC.

- HEADQUARTERS -

150 River Oaks Parkway

San Jose, CA 95134, U.S.A.

Phone: +1-408-922-0200 Fax: +1-408-922-0238

- SALES OFFICES -

West

1960 E. Grand Avenue

EI Segundo, CA 90245, U.S.A.

Phone: +1-310-955-5300 Fax: +1-310-955-5400

Central

101 Virginia Street, Suite 290

Crystal Lake, IL 60014, U.S.A.

Phone: +1-815-455-7630 Fax: +1-815-455-7633

Northeast

301 Edgewater Place, Suite 120

Wakefield, MA 01880, U.S.A.

Phone: +1-781-246-3600 Fax: +1-781-246-5443

Southeast

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Alpharetta, GA 30005, U.S.A.

Phone: +1-877-EEA-0020 Fax: +1-770-777-2637

EUROPE

EPSON EUROPE ELECTRONICS GmbH

- HEADQUARTERS -

Riesstrasse 15

80992 Munich, GERMANY

Phone: +49-(0)89-14005-0 Fax: +49-(0)89-14005-110

SALES OFFICE

Altstadtstrasse 176

51379 Leverkusen, GERMANY

Phone: +49-(0)2171-5045-0 Fax: +49-(0)2171-5045-10

UK BRANCH OFFICE

Unit 2.4, Doncastle House, Doncastle Road

Bracknell, Berkshire RG12 8PE, ENGLAND

Phone: +44-(0)1344-381700 Fax: +44-(0)1344-381701

FRENCH BRANCH OFFICE

1 Avenue de l' Atlantique, LP 915 Les Conquerants

Z.A. de Courtaboeuf 2, F-91976 Les Ulis Cedex, FRANCE

Phone: +33-(0)1-64862350 Fax: +33-(0)1-64862355

BARCELONA BRANCH OFFICE

Barcelona Design Center

Edificio Prima Sant Cugat

Avda. Alcalde Barrils num. 64-68

E-08190 Sant Cugat del Vallès, SPAIN

Phone: +34-93-544-2490 Fax: +34-93-544-2491

ASIA

EPSON (CHINA) CO., LTD.

28F, Beijing Silver Tower 2# North RD DongSanHuan

ChaoYang District, Beijing, CHINA

Phone: 64106655 Fax: 64107319

SHANGHAI BRANCH

4F, Bldg., 27, No. 69, Gui Jing Road

Caohejing, Shanghai, CHINA

Phone: 21-6485-5552 Fax: 21-6485-0775

EPSON HONG KONG LTD.

20/F., Harbour Centre, 25 Harbour Road

Wanchai, Hong Kong

Phone: +852-2585-4600 Fax: +852-2827-4346

Telex: 65542 EPSCO HX

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10F, No. 287, Nanking East Road, Sec. 3

Taipei

Phone: 02-2717-7360 Fax: 02-2712-9164

Telex: 24444 EPSONTB

HSINCHU OFFICE

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HsinChu 300

Phone: 03-573-9900 Fax: 03-573-9169

EPSON SINGAPORE PTE., LTD.

No. 1 Temasek Avenue, #36-00

Millenia Tower, SINGAPORE 039192

Phone: +65-337-7911 Fax: +65-334-2716

SEIKO EPSON CORPORATION KOREA OFFICE

50F, KLI 63 Bldg., 60 Yoido-dong

Youngdeungpo-Ku, Seoul, 150-763, KOREA

Phone: 02-784-6027 Fax: 02-767-3677

SEIKO EPSON CORPORATION

ELECTRONIC DEVICES MARKETING DIVISION

Electronic Device Marketing Department

IC Marketing & Engineering Group

421-8, Hino, Hino-shi, Tokyo 191-8501, JAPAN

Phone: +81-(0)42-587-5816 Fax: +81-(0)42-587-5624

ED International Marketing Department Europe & U.S.A.

421-8, Hino, Hino-shi, Tokyo 191-8501, JAPAN

Phone: +81-(0)42-587-5812 Fax: +81-(0)42-587-5564

ED International Marketing Department Asia

421-8, Hino, Hino-shi, Tokyo 191-8501, JAPAN

Phone: +81-(0)42-587-5814 Fax: +81-(0)42-587-5110

International Sales Operations

In pursuit of “Saving” Technology, Epson electronic devices.

Our lineup of semiconductors, liquid crystal displays and quartz devices

assists in creating the products of our customers’ dreams.

Epson IS energy savings.

http://www.epson.co.jp/device/

Technical Manual

S1C62N81

EPSON Electronic Devices Website

ELECTRONIC DEVICES MARKETING DIVISION

First issue March, 1990

Printed March, 2001 in Japan B