1.
ELECTRONICS ...................................................................................................... 3-1
1.1
General Block Diagram .................................................................................................... 3-1
1.2
Main PCB Block Diagram ................................................................................................. 3-2
1.3
Main PCB ......................................................................................................................... 3-3
1.3.1 CPU.....................................................................................................................................3-3
1.3.2 USB .....................................................................................................................................3-4
1.3.3 IEEE 1284 ...........................................................................................................................3-4
1.3.4 ROM ....................................................................................................................................3-5
1.3.5 Flash ROM ..........................................................................................................................3-6
1.3.6 SDRAM ...............................................................................................................................3-6
1.3.7 Optional RAM ......................................................................................................................3-7
1.3.8 EEPROM.............................................................................................................................3-7
1.3.9 Reset circuit ........................................................................................................................3-8
1.3.10 Engine I/O ...........................................................................................................................3-8
1.3.11 Panel I/O .............................................................................................................................3-8
1.3.12 Video I/O .............................................................................................................................3-8
1.3.13 Scanner control ...................................................................................................................3-9
1.3.14 Power supply.......................................................................................................................3-9
1.4
Engine PCB .................................................................................................................... 3-10
1.5
Power Supply.................................................................................................................. 3-11
2.
MECHANICS ........................................................................................................ 3-13
2.1
2.2
Scanner Mechanism....................................................................................................... 3-14
2.2.2 Scanner.............................................................................................................................3-14
2.3
Paper Transfer ............................................................................................................... 3-15
2.3.1 Paper supply .....................................................................................................................3-15
2.3.2 Paper registration..............................................................................................................3-15
2.3.3 Paper eject ........................................................................................................................3-16
2.4
Sensors .......................................................................................................................... 3-17
2.4.2 Toner sensors ...................................................................................................................3-17
2.4.4 Paper eject sensor ............................................................................................................3-18
2.4.6 Regist sensor ....................................................................................................................3-19
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MFC-8220
SERVICE MANUAL