COPYRIGHT © 2001 CANON INC.
2000 2000 2000 2000
CANON SmartBase PC1200s/iR1200s REV. 0 DEC. 2001
CHAPTER 4 OPERATION
4-6
1.3.2 Outlines of Functions
1.3.2.1 Image Processor PCB
It controls the machine as a whole, and communicates directly with all PCBs except the
sensor PCB and modular jack PCB.
Drive Control Block
The drive control mechanism acts on the reader motor and the ADF motor by the work of
the ASIC and motor drive IC.
Control Panel Control Block
The control panel control block receives the state of control keys while sending/receiving
data in serial communication with the control IC of the control panel PCB. Also, it sends
LED and LCD signals to the control panel PCB.
Image Processing Control Block
The image processing control block has the following functions:
• It subjects the digital image data from the analog processor PCB to enlargement/re-
duction processing, shading correction, smoothing, and other image processing,
thereby converting it to 600x600-dpi image signals (VD0, VD0*).
• It converts the analog image data from fax communication into 600x600-dpi image
signals (VD0, VD0*).
• It uses a horizontal sync signal (BD0*) as a trigger to send image signals (VD0,
VD0*) to the laser unit.
• The image data from the contact sensor is re-arranged, and the intensity of the contact
sensor LED is controlled.
Sensor Detection
It detects the state of each sensor of the rear unit and the ADF.
ESS Control
It controls the ESS function used to reduce the power consumption while the machine is
in standby state.
Memory Function
The 8MB (as mounted) SDRAM used for the storage of image data is capable of storing
about 79 pages in fax reception made of Canon Fax Standard Chart No.1. The image data is
backed up by a vanadium lithium secondary battery (BAT2), so that it remains intact for
about 2 hr after the machine is deprived of power. The 128-KB SRAM is used to store user
data and service data, and is backed up by a lithium battery (BAT1) so that the data may be
retained for about 5 yr after the machine is deprived of power.