Canon MultiPASS C5000 Service Manual page 95

a-4) Main ROM (IC301)
T h i s 8 Mbit ROM conl;lins the control progrnms (e.g. oprrzttion panel, scnnncr end
communications section etc.) for this fax.
a-5) SRAM (IC 302)
256 Kbit SRAM is backed up t,y lithium battery. SRAM holds data registered for
This
system control and communications mnnagcmcnt Information. Also, SRAM stores contnct
sensor LED light-on time dnto.
a-6) DRAM (IC 303, IC 307)
b) Communication control section
b-l) Modem IC (IC 701)
A Rockwell R144EFXL PQFP is used BS the modem IC. The MODEM IC carries out G3
modulation conforming to ITU-T standards V,27ter, V.29, V.17 and V.33 on tlonsnlltted
data received from the MPU during transmission During reception, the MODE11 IC
modulation on received signals frown the telephone line, according to the
s a m e s t a n d a r d s .
Document scanning section
c)
c-l) System controller IC (IC 401)
AD conversion
l
Input signals from the contact sensor aw Am converted.
*Generation of shading data (RGB color & Black and white)
ABC (Auto Background C~~ntrol)
l
Sets the slice level fiw each sea" line
* E d g e enhanccnwnt proccs%ng
l
Halftone processing
l
SRAM (IC 402, IC406)
c-2)
image processing function (IJHQ) are ns follows:
2 - 2 7
Chapter 2: Technical Reference