Theory Of Operations - Canon A-200 series Service Manual

PART VI
THEORY OF OPERATIONS
CONTENTS
VI-1. General .......................................................................................................... 43
VI-2. Main P.C.B. .................................................................................................... 45
VI-2-1. CPU.................................................................................................. 48
VI-2-2. RESET Signal and Clock Generator Circuit .. ..................................... 50
VI-2-3. NMI and INT Control Circuit .............................................................. 52
VI-2-4. Memory Map ..................................................................................... 53
VI-2-5. Memory............................................................................................. 54
VI-2-6. 110 Map and 1/0 Address Decoding Circuit ....... ................................ 57
VI-2-7. System Bus ....................................................................................... 60
VI-2-8. DMAC ........... .................................................................................... 63
VI-2-9. Printer Interface Circuit ..................................................................... 66
VI-2-10. RS-232C Interface Circuit .................................................................. 68
VI-2-11. Timer and Speaker Driver Circuit ...................................................... 70
VI-2-12. Keyboard Interface ............................................................................ 71
VI-2-13. PPI .................................................................................................... 73
VI-2-14. FDD Interface Circuit ......................................................................... 75
VI-3. Keyboard Unit ................................................................................................. 80
VI-4. Display Adapter Boards .................................................................................. 86
VI-4-1. Pin Description of the 68B45 ............................................................. 86
VI-4-2. Monochrome Display Adapter Board ...... ........................................... 87
VI-4-3. Color Display Adapter Board ............................................................. 100
VI-5. Power Supply Unit .......................................................................................... 114
41