Casio SF-8350 Troubleshooting guide

SF-8350(LX-572)
JUNE 1993
R
(without price)

CONTENTS
1. SCHEMATIC DIAGRAM................................................................................................ 1
2. SPECIFICATIONS ......................................................................................................... 5
3. TO REPLACE THE BATTERY...................................................................................... 6
4. ERROR MESSAGE ....................................................................................................... 7
5. TO RESET THE DIGITAL DIARY ................................................................................. 7
6. TO SAVE THE DATA TO OTHER MACHINE............................................................... 8
7. TO CHECK THE MEMORY CAPACITY...................................................................... 11
8. DISASSEMBLY ........................................................................................................... 12
9. BLOCK DIAGRAM ...................................................................................................... 14
10. CIRCUIT EXPLANATIONS
10-1. System chart................................................................................................. 15
10-2. Power supply circuit .................................................................................... 16
10-3. Battery voltage detection ............................................................................ 19
10-4. CPU pin description (µPD3055GF002-2BA) ............................................... 21
10-5. Gate array pin descriptions (µPD65005G-452-22) ..................................... 21
10-6. Power supply chip IC pin descriptions (SC371015FU) ............................. 21
10-7. Character generator ROM pin descriptions (HD62063B01) ..................... 22
10-8. Operation program ROM pin descriptions (µPD23C4001EBGW-301) ..... 23
10-9. RAM pin descriptions (µPD43256AGU-10/12/15LL) .................................. 23
10-10. RAM pin descriptions (HM62L864LFP-12MRL) ......................................... 23
11. DIAGNOSTIC OPERATION ........................................................................................ 24
12. TROUBLE SHOOTING................................................................................................ 29
13. PARTS LIST ................................................................................................................ 32
14. PCB VIEW ................................................................................................................... 34
15. ASSEMBLY VIEW ....................................................................................................... 35

— 1 —
1. SCHEMATIC DIAGRAM
1-1. Main Block

— 2 —
1-2. Display Block

— 3 —
1-3. Key Matrix

— 5 —
2. SPECIFICATIONS
Data storage:
Telephone/businesscard/memo/scheduledatastorage/recall, calendardisplay, marker,phrase memory,
secret area, editing, capacity display, auto display
Clock:
Average of accuracy ±3 seconds per day under normal temperatures; worldtime, schedule alam, daily
alarm
Calculation:
12-digit arithmeticcalculations, constants for+/–/× /÷,independent memory, percentages, squareroots,
24-digit approximations, date calculations, other mixed calculations
General:
Display element: 32-column ×6-line LCD
Memory capacity: 64 KB (56,006 bytes)
Main component: LSI
Power supply: Main Power Supply — Two CR2032 lithium batteries
Backup Power Supply — One CR2032 lithium battery
Power consumption: 0.05W
Battery life: Main: Approximately 120 hours (Repeated cycle of 1-minute data input
into Telephone Directory followed by 10-minute display. Operation
temperature of 20°C)
Approximately 150 hours (Continuous display in Telephone Direc-
tory. Operation temperature of 20°C)
Backup: 5years ifmain batteriesare replacedas soon as they becomeweak.
1 year if dead main batteries are left in the unit.
Auto power off: Approximately 6 minutes after last key operation
Operating temperature: 0°C ~ 40°C (32°F ~ 104°F)
Dimensions: Unfolded: 10.5H ×154W ×155.2mmD (3/8"H ×6"W ×61/8"D)
Folded: 17.9H ×154W ×78mmD (3/4"H ×6"W ×31/16"D)
Weight: 152.5g (5.4 oz) including batteries
Current consumption:
Power switch TYP. [µA] MAX [µA]
OFF 8 29
ON 1,447 13,258
ON (Operating) 6,707 19,958

— 6 —
3. TO REPLACE THE BATTERY
A) To replace the main batteries
Before replacing the main batteries, note the following precautions.
•Do not remove the back-up battery from the SF Unit while main batteries are removed.
• Be sure to replace both batteries at the same time, and do not use an old battery with a new
one.
1. Remove the screw that hold the battery compartment cover in
place.
2. Remove the battery compartment cover by sliding it in the
direction indicated by the arrow in the illustation.
3. Slide the main battery holder in the direction indicated by the
arrow.
4. Remove both old batteries and replace with two new ones.
• Use two new batteries. Wipe the surfaces of the batteries with a
soft, dry cloth. Make sure that the positive (+) sides of the
batteries are facing up (so you can view the positive sides as the
batteries lie in the battery compartment).
5. Replace the battery holder.
6. Replace the battery compartment cover and fasten it in place
using the screw.
B) To replace the back-up battery
Before replacing the back-up battery, note the following precautions:
• Do not remove the main batteries from the SF Unit while back-up battery is removed.
• Be sure to replace the back-up battery at least once a year.
1. Remove the screw that hold the battery compartment cover in
place.
2. Remove the battery compartment cover by sliding it in the
direction indicated by the arrow in the illustration.
3. First , remove this sticker from the back-up battery holder.
4. After removing this sticker, take the screw off that secures the
back-up battery holder in place, and then remove the battery
holder.
5. Remove the old battery and replace it with a new one.
• Wipe the surfaces of the battery with a soft, dry cloth.
Make sure that the positive (+) side of the battery is facing up (so
you can view the positive side as the battery lies in the battery
compartment.)
6. Replace the back-up battery holder and fasten it in place using
the screw, and replace the sticker over the battery holder.
7. Replace the battery compartment cover and fasten it in place
using the screw.

— 7 —
Message Meaning Action
DATA ITEM NOT Text specified for Correct or change
FOUND! search does not exist. specified text.
PASSWORD Wrong password Enter correct
MISMATCH! entered. password.
MEMORY FULL! No more room in Delete unnecessary
memory for storage of data items from
data. memory.
DATA ERROR! Abnormal data caused Consult the "DATA
CONSULT YOUR by strong impact, static ERROR" section on
OWNER'S MANUAL electricity, etc. page 3 of owner's
UNDER "DATA manual.
ERROR"
4. ERROR MESSAGE
5. TO RESET THE DIGITAL DIARY
Before describing the RESET operation, a note of WARNING — The following procedure will erase
all data stored in memory, including marked data items. Be sure to perform the RESET operation
only if you wish to clear all data.
To reset the SF Unit's memory
1. Switch on power and press the RESET button with a thin, pointed object.
The following message appears on the display.
2. Press Y to reset the SF Unit and clear everything from its memory. To abort the procedure
without clearing anything, press N .
DELETE ALL DATA ITEMS
STORED IN MEMORY ?
YES Y / NO N
* Important!
Note that the following operation will clear everything stored in the unit's memory. To
avoid accidental erasure of important data, be sure to perform this operation only while the
system language is set to your native language. See page 2 of owner's manual for
infomation on how to change the system language.

— 8 —
Following the RESET operation, the Home Time Display appears. The initial settings of the SF Unit after
reset are shown below.
HOME TIME: G.M.T.
JAN/1/1993 (FRI)
12:00 AM
12-hour format
WORLD TIME: New York
Daily Alarm: 12:00 PM
Sound: Schedule alarm ON
Daily alarm OFF
Key ON
Character input: CAPS
System Language: English
6. TO SAVE THE DATA TO OTHER MACHINE
SF-8350 can transfer customers data to other SF-8350 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 machine to clear all
data.
Important!
* You can not perform data communications with the CASIO SF-A series of SF Units (SF-A10,etc.).
* Be sure to replace the connector covers on the SF units when you are not performing data commu-
nications.
1) Turn off the power switch and connect the two units using the cable (SB-60 or SB-62) as shown in
the drawing.
ON
CLEAR/AC
CAL
2) Turn on the power switch of each machine.
3) The slave machine must be set the date of Feb. 3rd, 1901 into the memory under the calculator
mode.
Operation: 1 9 0 1 2 3
If you don't set the date, the "PASSWORD" isn't transferred to the slave machine.
DATE DATE
TIME TIME M+
R
DATE
TIME

— 9 —
HARDWARE PARAMETERS
PARITY EVEN ODD NONE
BIT LENGTH7 bits 7 bits 8 bits
BPS 1200 2400 4800 9600
TEL
2 Press to select "RECEIVE" and the following display appears to indicate that the slave
machine is ready to receive data.
1 SEND
2 RECEIVE
3 PRINT
4 HARDWARE PARAMETERS
5 DATA TO RAM CARD
6 PEN PRINTING
TEL
RECEIVE OK !
TO STOP, PRESS ESC
TEL
4) Check the hardware parameters, and if the units have another condition, reset as follows.
2
6) Set up the customer's machine.
1 While the transmitting unit is in the Calender Display, Telephome Directory, Business Card
Library, Memo Mode, or Schedule Keeper, press the key followed by to select
"DATA COMMUNICATION", and the following menu appears.
FUNCTION 4
*** ***
5) Set up the slave machine.
1 While in the Calender Display, Telephone Directory, Business Card Library, Memo Mode, or
Schedule Keeper, press the key followed by to select " DATA COMMUNICA-
TION", and the following menu appears.
TEL FUNCTION 4
4
TEL FUNCTION 41 SEND
2 RECEIVE
3 PRINT
4 HARDWARE PARAMETERS
5 DATA TO RAM CARD
6 PEN PRINTING
TEL
2
TEL FUNCTION 4 4
To change the hardware
parameters, press the
, , and
cursol keys.
To set the hardware
parameters, press the set
key.
FUNCTION

— 10 —
1 ONE DATA ITEM
2 MODE DATA ITEMS
3 ALL DATA ITEMS
— SEND —
TEL
SEND ALL DATA ITEMS ?
YES SET / NO ESC
TEL
NOW SENDING !
TO STOP, PRESS ESC
3 Press to select "ALL DATA ITEMS", and the following display appears to confirm
whether you wish to proceed.
2 Press to select "TRANSMIT" and the following menu appears.
1
3
4 Press the key to proceed with the data transmission, or press if you wish to cancel.SET ESC
1
3
SET
TEL
Data are transmitted in the sequence of Telephone Directory data, Business Card Library data, Memo
data, Schedule Keeper data and Calendar data.
* If the customer's machine uses full memory, it takes about one minute and ten seconds for this
transferring.
* 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 , , , ,
, , , key, to clear the error message. Then, take corrective
action and try data communication again.
BUSINESS CARD MEMO SCHEDULE
HOME TIME WORLR TIME CAL CALENDAR

— 11 —
Message Cause
STOPPED ! • ESC key pressed on transmitting or receiving unit.
• Memory area of receiving unit full.
• Battery power drops below a certain level.
TRANSMIT ERROR ! Cable connection broken or abnormal noise in cable.
MEMORY FULL ! Memory area of receiving unit full.
Following the memory reset operation, the display will appear as follows.
When the percentage of memory used reaches 100%, you will not be able to enter any more data into
memory.
7. TO CHECK THE MEMORY CAPACITY
The memory Capacity display tells you how much total memory is used for storage of Telephone
Directory, Business Card Library, Memo, Calendar, and Schedule Keeper data. It also shows the
percentage of total memory used, and how much total memory area remains. Press the key to
check the current memory capacity.
CAPA
00
00
0
56006
0

— 12 —
8. DISASSEMBLY (SF-8350)
1) To open display unit
1. Remove the key switch sheet from the display frame with care using a sharp tweezers and
remove 2 screws, then remove the display back cover.
2. Remove the blind plate of hinge and then release the 2 screws of hinge cover.
3. Release the 5 screws of display PCB and remove the display PCB.

— 13 —

— 14 —
C0~C47
CPU
ROM
ROM
(Character Generator)
(Operation Program)
HD62063B01
POWER SUPPLY
CHIP FOR LCD
SC371015FU
GATE ARRAY
µPD65005G-452-22
Power supply circuit
CARD LOCK SWITCH
FREE (OFF)
LOCK (ON)
VDD
GND
TX, RX
LCDDRIVE VOLTAGES
V1 ~ V4, VREG
TO KEYBOARD
RAM
DATA BUS
S112~S191S32~S111S0~S31
LCD 192X 48 dots
INTERFACE FOR
DATA TRANSMISSION
& DATA RECEPTION
OPEN (OFF)
LOCK (ON)
MSM6585AV
-Z-358B
LCD DRIVER LCD DRIVER LCD DRIVER
MSM6585AV
-Z-358B MSM6585AV -Z-358B
MAINSWITCH
RAM
9. BLOCK DIAGRAM
CD401-TS
µPD3055GF002-2BA
µPD23C4001EBGW-301
HM62L864LFP-12MRL
µPD43256AGX-
10/12/15LL
X 2 PCS.
NOTE: There are two types of the RAM chips:
1. Using 1pc. of HM62L864LFP-12MRL
2. Using 2pcs. of µPD43256AGU-10/12LL
NOTE

— 15 —
14. Apply VDD to ROM.
VREG,V1~V4
Output
for LCD
drive
PDB
µPD3055GF002-2BA
VDD2 VDD1
VO1
GND
(Pin3)
(Pin2)
(Pin32) (Pin20)
(Pin31)
(Pin25) (Pin40)
(Pin17)
(Pin24)
(Pin35)
VIN
GNDVDDVOT
LSI
MON
SWO
LSO VOB
µPD65005G-452-22
KAC KIO
ADDRESS BUS
2 MHz
VDD
ON
MAIN SWITCH
SW
GND
VDD
GND
Transistor Q1
(Pin53)
(Pin54)
(Pin41) (Pin1)
(Pin2)
(Pin3)
2
14
15
17
CPU
VDD
EO
7
(Pin69)
"H"
"H"
"H"
16
10
VDD
ADDRESS
DATA
"H"
VDD
1CR-2032 X 2 pcs.
Batteries
"L""H"
(Pin22)
"L" CE
"L" VCC
OSCOOSCI
INIT1 (Pin70)
(Pin30)
INT0
V2ON
Gate array
"L"
VDD
DATA BUS
(Pin40)(Pin45)
(Pin36)
"L"
(Pin29)
(Pin39)(Pin30)
4313
6
10-1. System chart
Generally, SF-8350 is working with the following steps.
10. Output "H" from V2ON terminal.
12. Output all LCD drive voltages.
11. Output "H" from VOT terminal.
13. Output "L" from VOB terminal.
17. CPU receives data from ROM.
16. CPU sends address to ROM.
2. Output VDD (4.5V).
1. Supply 6V to VDD1 and VDD2.
15. CPU sends ROM chip enable
signal from EO terminal.
5
OFF
10. CIRCUIT EXPLANATIONS
Open
9
8
3. Output "L" from SWO terminal.
5. Main switch ON.
6. Input "L" to SW terminal.
7. Output "L" from KAC terminal.
8. Push power on button switch.
4. Output "H" from LSO terminal.
9. CPU oscillation is generated.
12
11
ROM
(Operation program)
µPD23C4001EBGW-301
Power supply chip
SC371015FU

— 16 —
1) Power supply chip SC371015FU
V1
V COMP2
VDD1
VDD2
VO1
V4
V3
V COMP1
VREG
V2
C8 C7
VDD
PDB
GATE ARRAY
VOT terminal
FROM
R10
R9
R8
(4.3 V ~ 4.7 V)
CR2032
CR2032CR2032
The V comp1 and V comp2 outputs are the battery voltage detection outputs. According to
VDD1 and VDD2 voltages, V comp1 and V comp2 will change the status as follows:
V COMP 1
OUTPUTS STATUS " H " STATUS " L "
Memory battery
Main batteries
POWER SUPPLY CHIP
SC371015FU
13
14
15
16
21
8
1
2
19
7
10
9
12
11
6
18 20 17
++
22
GND1 GND2
31
When the batteries voltage When the batteries voltage
is more than 4.7 V. is less than 4.6 V.
When the batteries voltage When the batteries voltage
is more than 4.5 V. is less than 4.4 V.
V COMP 2
VSS(VREG) -3.5 -6.4
V1 +3.4 +3.1
V2 +2.5 +1.7
V3 -1.5 -3.6
V4 -2.5 -4.9
10-2.Power supply circuit
32
LCD DRIVE VOLTAGE Value (Approx.) [V]
Contrust : Min. Contrust : Max.
The IC SC371015FU is power supply chip for SF-
8350. When IC SC371015FU receives a Voltage
6V (CR-2032 ×2 pcs.) at the terminal VDD1(Pin
No.2), the regulated voltage VDD (4.3~4.7V) will
be applied to the VDD lines. The outputs Vss
(VREG) and V1~V4 are the LCD drive voltages.
When the terminal PDB becomes "H", those volt-
ages are generated by IC SC371015FU and ca-
pacitors C7 and C8 (ESCT1AY335R) and applied
to LCD driver IC MSM6385AV-Z-358B.
The resistors R8~R10 are used for dividing volt-
age V1~V4.

— 17 —
LSI MON
SWO
LSO
" L "
" H "
GNDVDD
CSB
" H "
FROM CPU
CS2 terminal (Pin 28)
(Pin 23)(Pin 24)
(Pin 40)
(Pin 39) (Pin 17) (Pin 22)
TO CPU
TO MAIN SWITCH
"L" "H"
OFF
ON SWO
SW
CPU
GATE ARRAY
MAIN SWITCH
VDD
"L"
"L"
KAC KIO
(Pin36)
(Pin40)
(Pin54) (Pin53)
POWER ON SWITCH
µPD65005G-452-22
GATE ARRAY
µPD65005G-452-22
(Pin 25)
(Pin 70)
INT0 terminal
µPD3055GF002-2BA
When VDD is applied from power supply IC
SC371015FU to gate array uPD65005G-452-
22, gate array will send "L" signal to active the
main switch signal from terminal SWO. Also,
gate array will send "H" signal to release the
INT0 terminal of CPU from LSO terminal.
The terminal CSB is for the chip select of gate
array. This signal is sent from CPU terminal
CS2. And when the VDD is applied to CPU,
CPU will send "H" signal to CSB terminal.
3) Main switch and power on switch
When the main switch is set to on position, SW terminal of CPU becomes "L", then CPU will send
"L" signal to KAC terminal to enable the system power on. The KI0 terminal is "H" when VDD is
applied to CPU. Therefore, when pressing the power on switch, CPU will generate a clock pulse (2
MHz) for start up the system.
GND
Open
2) Gate array

— 18 —
VDD
Transistor Q1
VOB E0
DATA
ADDRESS
ROM
µPD3055GF002-2BA
CPU
VCC
(Pin35)
µPD65005G-452-22
" L "
VDD
R4
(Pin1)
(Pin3)
(Pin2)
(Pin30)
VOT
VIN
"H"
"H"
V2ON
INT1
CPU
PDB
µPD3055GF002-2BA
POWER SUPPLY CHIP
SC371015FU
µPD65005G-452-22
GATE ARRAY
(Pin45)
(Pin69)
(Pin29)
(Pin30) (Pin31)
LCD drive voltages
VREG,V1~V4
When the system is start up, CPU will send "H" signal to VIN terminal of gate array from V2ON
terminal. Then, gate array will send "H" signal from VOT terminal to release interruption signal
INT1 of CPU and also, it will be sent to PDB terminal of power supply chip to generate LCD drive
voltages.
After gate array send VOT signal, gate array send "L" signal from VOB terminal to base terminal of
transistor Q1. Then, the VDD is applied to ROM (operation program), CPU can read a ROM
program data by E0 signal.
4) Power supply for LCD
5) ROM driving transistor
GATE ARRAY
µPD23C4001
EBGW-301

— 19 —
VCOMP2
VCOMP1
VCOMP1
"H"
"L"
CR-2032 X 2
P7
BLI
ONMK
VCOMP2
VCOMP1
Power Supply Chip
VDD1
VDD2
Main batteries
SC371015FU
µPD3055GF002-2BA
C P U
Gate Array
µPD65005G-452-22
GND2
(Pin1)
(Pin19)
(Pin37)
(Pin27)
(Pin7) (Pin79)
(Pin6)
GND1
(Pin22)
"H"
"L"
Less than about 4.4V
Batteries Voltage
Batteries Voltage
More than about 4.6V
VCOMP2
More than about 4.4V
Less than about 4.6V
(Pin32)
10-3.Battery voltage detection
The power supply IC chip SC371015FU has
two kind voltage detection circuit in it. Accord-
ing to the batteries input voltage, the detection
outputs V comp1 and V comp2 will change the
status as follow:
When CPU receive VCOMP2 detection signal, the machine shows "MAIN POWER SUPPLY
BATTERIES GETTING WEAK! REPLACE!" on the display. And when the batteries voltage is
weak more (approx. 4.53V), as the VCOMP1 detection signal becomes "L". The machine will
operate an auto power off operation.