Casio CE-6800 Service Manual Download

Page: 2 / 74

CONTENTS

CE-6800

Page

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

2. BLOCK DIAGRAM ....................................................................................... 3

3. TO OPEN THE UPPER CASE ..................................................................... 5

4. CIRCUIT EXPLANATION ............................................................................ 7

4-1. Power supply circuit ................................................................................................. 7
4-2. Reset and power down circuit .................................................................................. 8
4-3. CPU description ......................................................................................................... 8
4-4. Momory chip selection circuit ................................................................................ 11
4-5. Flash ROM1 address circuit ................................................................................... 12
4-6. Memory map ............................................................................................................ 12
4-7. Printer drive circuit .................................................................................................. 13
4-8. RS232C port COM1 circuit ...................................................................................... 14
4-9. RS232C port COM2 and COM3 circuit ................................................................... 15
4-10. To mount optional circuit ....................................................................................... 16

5. DIAGNOSTIC OPERATION ....................................................................... 17

5-1. To start the diagnostic program ............................................................................ 17
5-2. Check item ............................................................................................................... 17
5-3. Operation of each test ............................................................................................. 17
5-4. Switch status test .................................................................................................... 18
5-5. Individual function test ........................................................................................... 19
5-6. To exit the diagnostic mode ................................................................................... 27

6. IC DATA ..................................................................................................... 28

7. PCB LAYOUT ............................................................................................ 38

8. CIRCUIT DIAGRAM ................................................................................... 40

9. PARTS LIST ............................................................................................... 56