Drum Cartridge Presence Detection - Canon MF8100 Series Service Manual

Chapter 2
SCNT Board DCNT Board
Interrupting areas
ITB home position
sensor (PS71)
Drum cartridge
Interrupting areas
/SC
(Print command)
HP
HP HP HP HP HP HP
3
1 2 4 1 1 1
TOPSNS
/TOP
VIDEO signals
(Mono-color print)
Bk
Y M C
Bk
(Full-color print)
F-2-39

2.3.6.5 Drum Cartridge Presence Detection

0008-1714
This detection is utilized to detect the presence of the drum cartridge.
When the power is turned on or the top cover is closed, the DCNT Board determines the presence or absence of the cartridge by monitoring the following two items:
1) PS71 (ITB HOME POSITION DETECTION signal) outputs "L" periodically.
2) Output results from the TR2 (FEED BACK signal for secondary transfer bias) exceed a specified value.
The DCNT Board determines a cartridge presence only when the three conditions above are satisfied.
When the DCNT Board determines a cartridge absence, it stops the printer engine and notifies an drum cartridge out to the SCNT Board.
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