MFC-8440/8840D/8840DN, DCP-8040/8045D/8045DN
SERVICE MANUAL
iii
3.2.2
For Parallel Interface Cable Users
(For Windows
®
95/98/98SE/Me/2000 Professional/XP)
...................................................
2-13
3.2.3 For Windows NT
®
Workstation Version 4.0 Users
............................................................
2-18
3.2.4
For Network Interface Cable Users
(For Windows
®
95/98/98SE/Me/NT/2000 Professional/XP)
..............................................
2-20
3.2.5
For USB Interface Cable Users (For Mac
®
OS 8.6 to 9.2 Users)
......................................
2-23
3.2.6
For USB Interface Cable Users (For Mac
®
OS X 10.1/10.2.1 or greater Users)
...............
2-24
3.2.7
For Network Interface Cable Users (For Mac
®
OS 8.6 to 9.2 Users)
................................
2-25
3.2.8
For Network Interface Cable Users (For Mac
®
OS X 10.1/10.2.1 or greater Users)
.........
2-26
CHAPTER 3
THEORY OF OPERATION
.................................................
3-1
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
.....................................................................................................................................
3-3
1.3.3 IEEE 1284
...........................................................................................................................
3-4
1.3.4 ROM
....................................................................................................................................
3-4
1.3.5 Flash ROM
..........................................................................................................................
3-5
1.3.6 SDRAM
...............................................................................................................................
3-5
1.3.7 Optional RAM
......................................................................................................................
3-6
1.3.8 EEPROM
.............................................................................................................................
3-7
1.3.9 Reset circuit
........................................................................................................................
3-7
1.3.10 Engine I/O
...........................................................................................................................
3-7
1.3.11 Panel I/O
.............................................................................................................................
3-7
1.3.12 Video I/O
.............................................................................................................................
3-8
1.3.13 Scanner control
...................................................................................................................
3-8
1.3.14 Power supply
.......................................................................................................................
3-9
1.4
Engine PCB
....................................................................................................................
3-10
1.5
Power Supply
..................................................................................................................
3-11
1.5.1 Low-voltage power supply
.................................................................................................
3-11
1.5.2 High-voltage power supply
................................................................................................
3-12
2.
MECHANICS
........................................................................................................
3-13
2.1
Overview of Printing Mechanism
....................................................................................
3-13
2.2
Scanner Mechanism
.......................................................................................................
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
2.3.4 Duplex printing
..................................................................................................................
3-16
2.4
Sensors
..........................................................................................................................
3-17
2.4.1 Cover sensors
...................................................................................................................
3-17
2.4.2 Toner sensors
...................................................................................................................
3-17
2.4.3
Cassette sensor / Paper empty sensor
.............................................................................
3-18
2.4.4 Paper eject sensor
............................................................................................................
3-18
2.4.5 MP-PE sensor
...................................................................................................................
3-19
2.4.6 Document cover sensor
....................................................................................................
3-19
2.4.7
Document front sensor / Document rear sensor
...............................................................
3-20
2.4.8 DX-sensor PCB ASSY
.......................................................................................................
3-20