Canon iR C6800 Series Service Manual page 9

4.5 Image Processing.............................................................................................................................................. 4 17
4.5.1 Overview of the Flow of Image Data ........................................................................................................ 4 17
4.5.2 Construction of the Image Processing Modules........................................................................................ 4 18
4.5.3 Reader Input Image Processing ................................................................................................................. 4 19
4.5.4 Compression/Decompression and Editing Blocks .................................................................................... 4 20
4.5.5 Printer Output Image Processing............................................................................................................... 4 21
4.6 Flow of Image Data .......................................................................................................................................... 4 22
4.6.1 Flow of Image Data (copier function) ....................................................................................................... 4 22
4.6.2 Flow of Image Data (Box function) .......................................................................................................... 4 23
4.6.3 Flow of Image Data (SEND function) ...................................................................................................... 4 24
4.6.4 Flow of Image Data (fax transmission) ..................................................................................................... 4 25
4.6.5 Image Data Flow for Fax Reception Functions......................................................................................... 4 26
4.6.6 Flow of Image Data (PDL function) ......................................................................................................... 4 27
4.7 Parts Replacement Procedure........................................................................................................................... 4 28
4.7.1 Controller Box ........................................................................................................................................... 4 28
4.7.2 Main Controller PCB (main) ..................................................................................................................... 4 31
4.7.3 Main Controller PCB (sub) ........................................................................................................................ 4 35
4.7.4 Expansion Bus PCB ................................................................................................................................... 4 36
4.7.5 SRAM PCB................................................................................................................................................ 4 38
4.7.6 UFR Board ................................................................................................................................................. 4 40
4.7.7 Ethernet Board ........................................................................................................................................... 4 41
4.7.8 HDD ........................................................................................................................................................... 4 43
4.7.9 Controller Fan ............................................................................................................................................ 4 45
Chapter 5 Original Exposure System
5.1 Construction ....................................................................................................................................................... 5 1
5.1.1 Specifications, Control Mechanisms, and Functions .................................................................................. 5 1
5.1.2 Major Components ...................................................................................................................................... 5 2
5.1.3 Construction of the Control System ............................................................................................................ 5 4
5.1.4 Reader Controller PCB................................................................................................................................ 5 4
5.2 Basic Sequence................................................................................................................................................... 5 6
5.2.1 Basic Sequence of Operation at Power On ................................................................................................. 5 6
5.2.2 Basic Sequence of Operation in Response to a Press on the Start Key....................................................... 5 7
5.3 Various Control .................................................................................................................................................. 5 9
5.3.1 Controlling the Scanner Drive System ........................................................................................................ 5 9
5.3.2 Enlargement/Reduction.............................................................................................................................. 5 11
5.3.3 Controlling the Scanning Lamp ................................................................................................................. 5 11
5.3.4 Detecting the Size of Originals .................................................................................................................. 5 12
5.3.5 Dirt Sensor Control .................................................................................................................................... 5 16
5.3.6 Image Processing ....................................................................................................................................... 5 20
5.4 Parts Replacement Procedure........................................................................................................................... 5 23
5.4.1 Copyboard Glass ........................................................................................................................................ 5 23
5.4.2 Exposure Lamp .......................................................................................................................................... 5 23
5.4.3 Reader Controller PCB .............................................................................................................................. 5 27
5.4.4 Interface PCB............................................................................................................................................. 5 30
5.4.5 Inverter PCB .............................................................................................................................................. 5 32
5.4.6 CCD Unit ................................................................................................................................................... 5 33
5.4.7 Scanner Motor............................................................................................................................................ 5 35
5.4.8 ADF Open/Close Sensor............................................................................................................................ 5 37
5.4.9 Scanner HP Sensor..................................................................................................................................... 5 39
5.4.10 Original Sensor ........................................................................................................................................ 5 41
5.4.11 Cooling Fan.............................................................................................................................................. 5 42
5.4.12 Scanner Drive Cable ................................................................................................................................ 5 43
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