COPYRIGHT © 2002 CANON INC.
2000 2000 2000 2000
CANON iR1200/iR1300 Series REV. 0 AUG. 2002
4-7
CHAPTER 4 OPERATION
Speaker Control (if equipped with fax functions.)
It turns on/off or control the volume of the error sound, key sound, and line monitor
sound generated by the speaker.
Memo
The volume of the line monitor or the sound of the key sound or the error
sound is adjusted in user mode.
Communication Control Block (if equipped with fax functions)
The communication control block detects line signals (CNG, DTMF). The 33.6-kps mo-
dem is controlled by the main CPU on the image processor PCB for modulation and de-
modulation of transmission/reception data. It also is used to send the DTMF signal.
1.3.2.2 DC Controller PCB
Fixing Heater Control Block
The fixing heater control block monitors the temperature reading of the thermistor to en-
sure that the temperature of the heater reaches a specific level. If an error is detected in the
temperature of the heater, it stops the power to the heater.
High-Voltage Control Block
The high-voltage control block controls the high voltage for the primary charging roller,
developing cylinder, transfer charging roller, and fixing film. Of these, the application of DC
bias is controlled based on the readings of the humidity around the machine (checked by the
humidity sensor) of the primary charging roller, developing cylinder, and transfer roller.
This mechanism of control is used to increase the bias level in a low humidity environ-
ment, thereby improving the reproduction of images.
In a medium to high humidity environment, on the other hand, it serves to save on the
level of toner consumption.
Drive Control Block
The drive control block controls the main motor, pickup solenoid, and fan.
Sensor Detection
The sensor condition of the printer block and the various pickup block are checked to
monitor the drive mechanism and to detect the presence/absence of the cartridge, collection
of waste toner, presence/absence of the toner bottle, and the relative humidity around the
machine.
Image Processor PCB Interface block
The image processor PCB interface block sends the horizontal sync signal (BD0*) to the
image processor PCB. It also returns a state signal in response to a command signal (serial)
from the image processor PCB, thereby communicating the state of the printer block to the
image processor PCB.
