Canon MultiPASS C50 Service Manual page 111

c) Color copy
(1) Using the LED as a light source, the image is scanned by the contact sensor, and RGB analogue image
data is sent to the SCNT board.
(2) The System controller IC (Internal UHQ unit) converts analogue image data from the contact sensor
to RGB digital image data.
(3) The system controller IC converts the RGB digital image data from serial data to parallel data, and
writes them to the DRAM.
(4) The color image processing IC converts the RGB data on the DRAM into CMYK print data, then
returns it to DRAM storage.
(5) The system controller IC converts the CMYK printer data to BJ printer head control signals, and then
sends the signals to the BJ print head, via the BJ controller IC. Simultaneously, the printer MPU
sends motor control signals to the carriage motor and line feed motor via the driver IC.
SCNT board
Carriage motor
a System controller IC
b DRAM
c MPU
d Color image processing IC
e BJ controller IC
f MPU(Printer)
g Driver IC(Carriage motor)
h Driver IC(Paper feed motor)
Figure 2-22 Color Copy Image Signal Flow
(5)
b
(3)
b
(2)
a
c (4) (4)
d
(5)
PCNT board
g
(5)
f
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Chapter 2: Technical Reference
Contact sensor
(1)
NCU
board
(5)
e
h
(5)
Paper feed motor