Canon MultiPASS C50 Service Manual page 110

Part 1: Facsimile
b) G3 Reception
(1) Image signals received by L1, L2, pass through the hybrid circuit in the NCU, and are amplified. The
modem demodulate these images, and writes them to the DRAM.
(2) The MPU decodes the demodulate image data, checks errors, stores them in the DRAM, encodes the
data and rewrites them into the DRAM.
(3) The system controller IC converts the decoded data from run-length data to raw data, and converts 8
dot/mm fax data into 360 dpi resolution converted printer data, and writes them to the DRAM.
(4) The system controller IC converts the resolution converted 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
a
b
c
d
e
f
g
h
(4)
(2)
(1)
c
PCNT board
Carriage motor
g
MODEM IC
DRAM
MPU
System controller IC
BJ controller IC
MPU(Printer)
Driver IC(Carriage motor)
Driver IC(Paper feed motor)
Figure 2-21 G3 Reception Image Signal Flow
b
(3)
b
d
(2)
a
(1)
(1)
(4)
e
(4)
f
2-30
(1)
NCU
board
(4)
h
(4)
Paper feed motor