Casio SF7900E, SF-8900 Service Manual

SF-7900E(LX-552A) SF-8900(LX-552I/J)

JAN. 1995

(without price)

(with price)

SF-7900E

CONTENTS

SPECIFICATIONS ................................................................................................................ 1

TO REPLACE THE BATTERY ............................................................................................. 2

TO CHECK THE MEMORY CAPACITY............................................................................... 2

ERROR MESSAGE............................................................................................................... 3

TO RESET THE SF UNIT'S MEMORY................................................................................. 4

TO SAVE THE DATA TO ANOTHER UNIT ......................................................................... 5

BLOCK DIAGRAM................................................................................................................ 8

CIRCUIT EXPLANATIONS

System chart................................................................................................................. 9

Power supply circuit .................................................................................................. 10

CPU pin description (HD62076C03).......................................................................... 12

Gate array pin descriptions (SSC2571F0A) ............................................................. 13

Gate array pin descriptions (SSC2571F0B) ............................................................. 14

Operation program ROM pin descriptions .............................................................. 15

RAM pin descriptions ................................................................................................ 15

DIAGNOSTIC OPERATION................................................................................................ 16

TROUBLESHOOTING........................................................................................................ 21

SCHEMATIC DIAGRAM

Main PCB .................................................................................................................... 23

Display PCB................................................................................................................ 25

Key Matrix ................................................................................................................... 26

Key Matrix (Display side)........................................................................................... 27

PARTS LIST........................................................................................................................ 29

ASSEMBLY VIEW .............................................................................................................. 31

SPECIFICATIONS

Main modes: Telephone Directory, Business Card Library, Memo, Schedule Keeper,

Expense, Reminder, Calendar, Home Time, World Time and Calculator

Data storage: Storage and recall of telephone, business card, memo, schedule, expense,

reminder data, calendar display, secret area; editing; memory status display

Clock: World Time; reminder alarm; schedule alarm; daily alarm; accuracy under

normal temperatures: ±3 seconds average

Calculation: 12-digit arithmetic calculations; arithemetic constants (+, –, ×, ÷); independ-

ent memory; percentages; square roots; 24-digit approximations; date calculations; other mixed calculations

General: Display element: 16-column × 8-line LCD Memory capacity: SF-7900E: 128KB (103436 bytes)

SF-8900: 256KB (234508 bytes)

Main component: LSI Power supply: 3 lithium batteries (CR2032) Power consumption: 0.07 W Battery life*: Approximately 170 hours continuous operation in Telephone Directory;

approximately 130 hours repeating one minute of input and 10 minutes of display in Telephone Directory; approximately 12 months for memory back up * The batteries that come installed in this unit when you purchase it are for

factory test purposes, so they will probably not provide normal service life.

Auto power off: Approximately 6 minutes after last key operation Operating temperature: 0°C ~ 40°C (32°F ~ 104°F) Dimensions:

Unfolded: 9.55H × 144W × 155D mm (3/8"H × 5 11/16"W × 6 1/8"D) Folded: 15.95H × 144W × 77.5D mm(5/8"H × 5 11/16"W × 3 1/16"D)

Weight: 123g (4.3 oz.)

• Design and specifications are subject to change without notice.

Current consumption:

Power switch TYP. [µA] MAX [µA] OFF 11.7 37.1 ON 1,670.0 13,711.0 ON (Operating) 4,520.0 16,645.0

— 1 —

TO REPLACE THE BATTERY

Screw

RESET

To replace the batteries

1. Loosen the screw on the back of the SF unit that holds the battery compartment cover in place, and remove the cover.

Caution In the next step, be sure to remove only one battery at a time. Otherwise, you will lose all data stored in memory.

2. Loosen the screw that secures one of the three battery holders in place and remove the battery holder.

3. Replace the old battery with a new one, making sure that the positive (+) side of the new battery is facing up (so you can see it).

4. Replace the battery holder and secure it by tightening its screw.

TO CHECK THE MEMORY CAPACITY

Hold down CAPA to display a screen that shows the current memory status. To clear the memory status display, release

Remaining memory capacity

CAPA .

C A P A C I T Y

76420BytesFREE 27016BytesUSED

26 %

Total number of characters stored in memory

10050

— 2 —

ERROR MESSAGE

Message Meaning Action

DATA ITEM Search operation Current search operation NOT FOUND! attempted when no data cannot be performed. NO DATA is stored in memory.

IN MEMORY!

DATA ITEM Data specified in search Change specification or NOT FOUND! operation does not exist cancel search.

MEMORY FULL! No more room in memory Delete unnecessary data

ALARM TIME Attempt to set a Schedule Set a different alarm time ALREADY USED! Keeper alarm time that or change the existing alarm

ALARM TIME Attempt to set a Schedule Set a different alarm time ALREADY PASSED! Keeper alarm time for a (for a future time/date.)

in memory.

for storage of data. items from memory.

is already used for time to another one. another entry.

time/date that is already passed.

SECRET DATA! Alarm for a secret Enter the secret memory

memory area data item is area to view details of the sounding. alarm.

PASSWORD Attempt to enter the Use the correct password. MISMATCH! secret memory area

using a password that does not match the one preset for the secret area.

TRANSMIT ERROR! Error during data Cancel the data

communications. communications

STOPPED! operation and try again. DATA ERROR! Data corrupted by strong See page 11 of the

CONSULT THE impact, electrostatic owner's manual. OWNER'S MANUAL! charge, etc.

SAME TYPE Attempt to store a label Use a different label. ALREADY USED! that is identical to one

already stored.

— 3 —

TO RESET THE SF UNIT'S MEMORY

The following procedure erases all data stored in the memory of the SF unit. Perform the following operation only when you want to delete all data and initialize the settings of the SF unit. Remember – you should always keep copies of important data by writing it down, by transferring it to a personal computer or other SF unit.

To reset the SF Unit's memory

RESET button

RESET

1. Switch on power and press the RESET button with a thin, pointed object.

Warning! The next step deletes all data stored in the SF unit's memory. Make sure that you really want to delete the data before you continue!

2. Press Y to reset the memory and delete all data or N to abort the reset operation without deleting anything.

Following the reset operation described above, the Home Time display appears and the SF unit settings are initialized as noted below.

Home Time: 12-hour format

JAN/1/1995

AM/12:00 00 World Time: Washington D.C. Daily Alarm: 12:00 PM Sound: Schedule alarm → ON

Reminder alarm → ON

Daily alarm → OFF

Key → ON Character input: CAPS

— 4 —

TO SAVE THE DATA TO ANOTHER UNIT

SF-7900 can transfer customers data to another SF-7900 with memory protection only when replacing the LCD or the outer case.

How to transfer the data

* Before connecting the cable (SB-60 or SB-62), be sure to reset the slave unit to clear all

data.

1) Turn off the power switch and connect the two units using the cable (SB-60 or SB-62) as shown in

the drawing.

2) Turn on the power switch of both units.

3) The slave unit must be set the date of Feb. 3rd, 1901 into the memory under the calculator

mode.

Operation: 1 DATE 2 DATE 3 DATE M+

CLEAR

CAL

If you don't set the date, the "PASSWORD" isn't transferred to the slave unit.

4) Check the hardware parameters, and if the units have another condition, reset as follows.

To change the hardware parameters, press the

, , and

cursol keys.

PARITY NONE

BIT LENGTH 7

SET UP

To set the hardware parameters, press the SET

BPS 9600

key.

TEL

FUNC 4 4

— 5 —

5) Set up the slave unit.

1 While in the Calendar Display, Telephone Directory, Business Card Library, Memo Mode, or

Schedule Keeper, press the FUNCTION key followed by 4 to select " DATA COMM", and the following menu appears.

TEL

FUNCTION 4

1 SEND

2 RECEIVE

3 PRINT

4 SET UP

2 Press 2 to select "RECEIVE" and the following display appears to indicate that the slave unit

is ready to receive data.

DATA

RECEIVE OK

TO STOP PRESS [ESC]

6) Set up the customer's unit.

1 While the transmitting unit is in the Calendar Display, Telephone Directory, Business Card

Library, Memo Mode, or Schedule Keeper, press the FUNCTION key followed by 4 to select "DATA COMM", and the following menu appears.

TEL

FUNCTION 4

1 SEND

2 RECEIVE

3 PRINT

4 SET UP

2 Press 1 to select "SEND" and the following menu appears.

SEND

1 ONE ITEM

2 MODE DATA

3 ALL DATA

— 6 —

3 Press 3 to select "ALL DATA". The following display appears to confirm if you wish to

proceed.

SEND ALL

DATA ITEM ?

SET / ESC

4 Press the SET key to proceed with the data transmission, or press ESC if you wish to

cancel.

SET

NOW SENDING !

TO STOP, PRESS ESC

Data are transmitted in the sequence of Telephone Directory data, Memo data, Reminder data, Schedule Keeper data and Calendar data.

* The following messages appear on the display of the receiving unit when a problem occurs during

data communications. All data transferred up to display of the message is retained in memory, but data communication is terminated.

If one of the following error messages appear, press the , , , , ,

CAL

CALENDAR

, keys, to clear the error message. Then, take corrective action and try data

TEL

MEMO

HOME/WORLDSCHEDULE

REMINDER

communication again.

Message Meaning Action

TRANSMIT ERROR! Error during data Cancel the data STOPPED! communications. communications operation

and try again.

DATA ERROR! Data corrupted by strong See page 9 of the owner's CONSULT THE impact, electrostatic manual. OWNER'S MANUAL! charge, etc.

— 7 —

BLOCK DIAGRAM

LCD 96 × 64 dots

CD760-TS

KEYBOARD

PCB-L589-E4

TO KEYBOARD

C0~C63

MSM6585AV

-Z-358B

DATA BUS

CPU

HD62076C03

LSI1

ROM

(Operation Program)

LSI5

S16~S95S0~S15

LCD DRIVER LCD DRIVER

MSM6585AV

-Z-358B

OPEN (OFF)

LOCK (ON)

MAIN SWITCH

LCD DRIVE VOLTAGES

V1 ~ V5

VDD

GND

PCB-L589-E2

PCB-L522-1(SF-7900E)

PCB-L552-1(SF-8900)

RAM

MSM51008AFP-10LL

LSI3, LSI4

SF-7900E: RAM × 1 SF-8900: RAM × 2

Power supply circuit

GATE ARRAY

SSC2571

LSI2

INTERFACE FOR DATA TRANSMISSION

& DATA RECEPTION

— 8 —

+ 22 hidden pages