Casio CE-235, Service Manual

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CONTENTS
1. FEATURES.............................................................................................................. 1
2. SPECIFICATION .................................................................................................... 1
3. MAC (Memory All Clear) OPERATION .............................................................. 2
4. DIAGNOSTIC OPERATION ................................................................................ 3
4-1. How to start .................................................................................................. 3
4-2. Mode switch and PAD status display check .................................................... 4
4-3. Hard key code check .................................................................................... 4
4-4. Hard check function ..................................................................................... 5
5. OPTION CIRCUT ................................................................................................... 8
6. CIRCUIT EXPLANATION ..................................................................................... 9
6-1. Power supply circuit ...................................................................................... 9
6-2. CPU ............................................................................................................. 11
6-3. Motor error detection circuit .......................................................................... 12
6-4. Mode key switch status read ......................................................................... 13
6-5. RAM address / head drive signal switching circuit ............................................ 13
6-6. Initilize IC (Reset IC) ...................................................................................... 14
6-7. Printer error condition of CPU ........................................................................ 14
7.TO OPEN THE UPPER CASE ............................................................................ 15
8. PCB LAYOUT ........................................................................................................ 16
9. CIRCUIT DIAGRAM .............................................................................................. 17
10. PARTS LIST ........................................................................................................ 28