Casio SF-4400 Troubleshooting guide

JUN. 1994
R
(with price)
SF-4400(LX-594A)
SF-4600B(LX-594E/F)
SF-4400 SF-4600B

CONTENTS
1. SCHEMATIC DIAGRAM.................................................................................................... 1
1-1. MAIN PCB.................................................................................................................. 1
1-2. KEY MATRIX ............................................................................................................. 2
2. SPECIFICATIONS ............................................................................................................. 3
3. TO REPLACE THE BATTERIES....................................................................................... 5
4. DATA TRANSFER............................................................................................................. 6
5. OPERATION REFERENCE............................................................................................. 10
5-1. RESET OPERATION ............................................................................................... 10
5-2. TO ADJUST THE DISPLAY CONTRAST ............................................................... 11
5-3. TO CHECK THE MEMORY STATUS...................................................................... 11
5-4. THE SOUND MENU................................................................................................. 11
6. LSI, IC (Pin function) ...................................................................................................... 12
6-1. CPU.......................................................................................................................... 12
6-2. RAM:µPD43256G-101215LL (LSI2,LSI3) ............................................................... 13
6-3. VOLTAGE REGULATOR:S-81253SGUP (REG1) .................................................. 14
6-4. VOLTAGE DETECTOR:S-80752AN (DET1)........................................................... 14
7. TROUBLESHOOTING..................................................................................................... 15
8. HARD CHECK ................................................................................................................. 18
9. ASSEMBLY VIEW ........................................................................................................... 23
10. PARTS LIST .................................................................................................................... 25

— 1 —
1. SCHEMATIC DIAGRAM
1-1. MAIN PCB
NOTE: 1.LSI4, R3, R11 are not mounted.
2.R1, R2 are not used.

— 2 —
1-2. KEY MATRIX

— 3 —
2. SPECIFICATIONS
Data storage:
Storage and recall of telephone, memo, schedule, 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:
10-digit arithmetic calculations; arithmetic constants (+, –, x, ÷); independent memory; percentages;
square roots; 20-digit approximations; date calculations; other mixed calculations.
General:
Display element: 16-column x 4-line LCD
Memory capacity: SF-4400: 32 KB (28579 bytes)
SF-4600B: 64 KB (61347 bytes)
Main component: LSI
Power supply: 2 lithium batteries (CR2032)
Power consumption: 0.05W
Battery life:
Approximately 450 hours continuous operation in Telephone Directory
Approximately 380 hours repeating one minute of input and 10 minutes of display in Telephone
Directory
Approximately 12 months for memory backup
Auto power off: Approximately 6 minutes after last key operation
Operating temperature: 0°C ~ 40°C (32°F ~ 104°F)
Dimensions:
Unfolded: 10.6H x 141W x 159.5Dmm (3/8"H x 5 1/2"W x 6 1/4"D)
Folded: 12.4H x 141W x 82Dmm (1/2"H x 5 1/2"W x 3 1/4"D)
Weight: 98.2g (3.5 oz)
Current consumption:
Storage Capacity:
The 64K bytes memory capacity (32K bytes for SF-4400) includes a 61347 bytes user area (28579
bytes for SF-4400). The following shows examples of what this means for the storage of data in
each mode.
Telephone Directory:
Approximately 2920 (1360 for SF-4400), under the following conditions:
8-character name
10-character telephone number
Power switch TYP. [µA] MAX [µA]
OFF 5.15 10.0
ON 256 420

— 4 —
Approximately 1460 (680 for SF-4400), under the following conditions:
8-character name
10-character telephone number
20-character address
Memo:Approximately 2780 (1290 for SF-4400), 20-character memos.
Schedule Keeper:
Approximately 1910 (890 for SF-4400), under the following conditions:
1 item per day, 20 characters per item
30 days per month
Starting time specified, alarm time set
Approximately 2190 (1020 for SF-4400), under the following conditions:
1 item per day, 20 characters per item
30 days per month
Starting time specified, no alarm time
Reminder:
Approximately 3600 (1680 for SF-4400), under the following conditions:
10 characters per item
Alarm time set
Approximately 4080 (1900 for SF-4400), under the following conditions:
10 characters per item
No alarm time

— 5 —
Screw
RESET
3. TO REPLACE THE BATTERIES
1) Loosen the screw on the back of the SF-4400/4600B
that holds the battery compartment cover in place,
and remove the cover.
2) Loosen the screw that secures one of the two battery
holders in place and remove the battery holder.
Caution:
Be sure to remove only one battery at a time.
Otherwise, you will lose all data stored in memory.
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.
• Be sure careful that you do not over tighten the screw.
5) Repeat steps 2) through 4) for the other two batteries.
• Be sure to replace all two batteries. Never mix old batteries with new ones, and be sure to use
CR2032 lithium batteries only.
6) After you replace all two batteries, replace the battery compartment cover and secure it by tightening
its screw.
• Be careful that you do not over tighten the screw.

— 6 —
2) Turn on the power switch of each machine.
3) The slavemachine mustbeset thedate ofFeb. 3rd, 1901into thememory underthe calculator mode.
Operation: 1. Press
2. Select "CAL" mode or press 6.
3.
If you don't set the date, the "PASSWORD" isn't transferred to the slave machine.
4. DATA TRANSFER
SF-4400/SF-4600B can transfer customers data to other SF-4400/SF4600B with memory protection
only when replacing the LCD or the outer case. How to transfer the data.
* Before connecting the cable (SB-60/62), be sure to reset the slave machine to clear all data.
1) Turn off the power switch and connect the two units using the cable (SB-60/62) as shown in the
drawing.
SB-60/62 accessory cable
ON MENU
TIME TIME TIME M+
DATE DATE DATE R
123
M SUN
1901/ 2/ 3

— 7 —
Setting up for Data Communications
The following procedures describe what you should do to set up for data communications between
two SF Units or between an SF Unit and a personal computer. In addition to hardware connections,
it details how to set up the communications parameters and how to set up the SF-4400/4600B to
receive data. By following these instructions carefully, you can be ensured of successful
communications every time.
To connect two SF Units
1. Check to make sure that the power of the two SF Units is switched off.
2. Remove the covers from the connectors on the two SF Units.
3. Connect the two SF Units using the optional SB-60/62 cable. You can also connect them using
an SB-60/62 cable.
Important
Be sure to replace the connector covers on the SF Units when you are not performing data
communications.
4) Check the hardware parameters.
1. Select "TEL" mode or press 1under MENU screen.
2. Press FUNC twice to display the second function menu.
• You can perform the above operation while the initial screen of the Memo Mode, Schedule
Keeper, Calendar, or Reminder is displayed also.
3. Press 4 to select DATA COMM.
4. Press 3 to select SET UP.
✻✻ SET UP PAR. ✻✻✻
PARITY E O N
BIT LENGTH 78
BPS 4800 9600
3
CAPS
•Nis blinking.
*If the password isn't
registered in the SF unit,
display shows Xinstead
of "1".
FUNC FUNC 1* TO SECRET AREA
2 ALL DELETE
3 LABEL EDIT
4 DATA COMM
CAPS
4
1 SEND
2 RECEIVE
3 SET UP PAR.
CAPS

— 8 —
*If the password isn't
registered in the SF unit,
display shows X instead
of "1".
5. If the units have another condition, reset as above.
• To change the parameters
1. Use the and — cursor keys to change the selected parameter on the display.
2. Use the and cursor keys to change the high-lighted setting of the currently selected
parameter.
3. Press SET to store them in memory.
5) Set up the slave machine
1. While an initial screen is displayed, press FUNC twice to display the second function menu.
• You can perform the above operation while the initial screen of the Memo Mode, Schedule
Keeper, Calendar, or Reminder is displayed also.
2. Press 4 to select DATA COMM.
3. Press 2 to select RECEIVE.
6) Set up the customer’s machine.
1. While an initial screen is displayed, press FUNC twice to display the second function menu.
• You can perform the above operation while the initial screen of the Memo Mode, Schedule
Keeper, Calendar, or Reminder is displayed also.
1* TO SECRET AREA
2 ALL DELETE
3 LABEL EDIT
4 DATA COMM
SET
2
DATA
RECEIVE OK
TO STOP
PRESS (ESC)
CAPS
CAPS
FUNC FUNC
∇
∇
∇
*If the password isn't
registered in the SF unit,
display shows X instead
of "1".
FUNC FUNC 1* TO SECRET AREA
2 ALL DELETE
3 LABEL EDIT
4 DATA COMM
CAPS
4
1 SEND
2 RECEIVE
3 SET UP PAR.
CAPS