Canon Laser Shot LBP-1120, Service Manual

Page: 21 / 117

CHAPTER 2
2 - 2
B. Basic Operation Sequence
The operation sequence of this printer is controlled by the microcomputer on the engine controller PCB. The table
describes the purpose of each period from the time the printer is turned ON until the main motor stops rotating after the
completion of printing. Refer to the APPENDIX for the detailed timing chart.
Table 2-1-1
Purpose Remarks
WAIT
( W A I T
period)
From power-ON until the end of
the main motor initial rotation.
Period
To clear the drum surface of
potential and to clean the transfer
charging roller.
From the end of the WAIT period or
the LSTR period until the input of
the pick-up command from the
interface controller.Or,from the end
of the LSTR period until
power-OFF.
From the input of the pick-up
command from the interface
controller until the paper
reaches the paper top sensor.
From the end of the initial rotation
until the primary voltage going
OFF.
From the time the primary
voltage goes OFF until the
main motor discontinues rotating.
STBY
(STANDBY)
INTR
(INITIAL
ROTATION
period)
PRINT
(Print)
LSTR
(LAST
ROTATION
period)
To keep the printer ready to print.
To stabilize the photosensitive
drum sensitivity in preparation
for printing. Also to clean the
transfer charging roller.
To form images on the
photosensitive drum based on the
VIDEO signals (/VDO,VDO) input
from the interface controller and
to transfer the toner image on to
the paper.
To deliver the last page. Also to
clean the transfer charging roller. If the pick-up command
is input from the interface
controller, the printer
enters the INTR period
immediately after the
end of the LSTR period.
Detects whether the
cartridge is installed or not.