Operation - Canon GP335 Service Manual

CHAPTER 10 EXTERNALS/AUXILIARY MECHANISMS
B. Operation
1. Data Communication
The exchange of data is controlled by the IP-CPU (CPU for the image processor PCB).
2. LCD Processing
The IP-PCU sends data (display data) to the control panel CPU PCB as instructed by a
program. The control PCU PCB, on its part, relays the data to the LCD panel.
3. LCD Contrast Adjustment
The machine is equipped with a dial (on the control panel) to enable the user to adjust the LCD
contrast. The user may turn the dial to obtain LCD contrast of his/her choice.
4. Control Panel CPU
• Monitors key inputs for transmission to the IP-CPU. (keypad keys, function keys)
• Controls the buzzer sound.
• Turns on/off the control panel LCD.
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COPYRIGHT © 1999 CANON INC. CANON 405/335 REV.0 JAN. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)