Canon LBP1760P, Service Manual

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2. Operation
When the power is switched ON, the printer enters the WAIT mode.
At the end of the WAIT mode, the engine controller sends the READY signal (/RDY) to the
video controller to inform that printer is ready to print.
When the /RDY signal is “L” and data for a page is prepared, the video controller sends the
PRINT signal (/PRNT) to the engine controller.
When the engine controller receives the /PRNT signal, it starts the operation of the INITIAL
ROTATION (INTR) period.
At the end of the INTR period, the engine controller sends the VERTICAL SYNC signal (/TOP)
to the video controller.
When the HORIZONTAL SYNC signal (/BD) from the engine controller is received, the video
controller sends the VIDEO signal (/VDO) synchronized to the /BD signal and the /TOP signal
to the laser driver through the engine controller.
In response to the /VDO signal, the laser driver switches the laser diode ON and OFF.
The laser beam emitted from the laser diode by the /VDO signal is scanned across the pho-
tosensitive drum with the scanning mirror to form the latent electrostatic image.
The latent electrostatic image on the photosensitive drum is developed and transferred onto
the paper by the electro-photographic process, and the paper is delivered to the face-down or
face-up tray.
While a page is printed, the engine controller checks if another /PRNT signal is being sent
from the video controller.
If no signal is received, the engine controller completes the PRINT period and starts the LAST
ROTATION period (LSTR). At the end of this period, the printer enters STANDBY (STBY) mode.
If the PRINT signal is being sent, continues the print sequence. Then, the last rotation oper-
ation is performed, and the printer enters the STANDBY mode again.
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CHAPTER 2