HP 3150 manual Basic sequence of operation formatter-to-printer, Timing Period Purpose Remarks

Basic sequence of operation (formatter-to-printer)

The formatter and the ECU share information during printer operation. The ECU-to-formatter connector (J201) forms a link which operates as a serial data bus. This allows printer status, command information, and dot-image data to be passed between the two. The following events take place during normal printer operation:

Table 12. Timing

Period	Purpose	Remarks
WAIT (WAIT period)	To clear the drum surface of its
From power ON to the end of the	charge and to clean the transfer
initial rotation of the main motor.	charging roller.
STBY (STANDBY)	To maintain the printer in ready
From the end of the WAIT period or	mode.
the LSTR period until the input of
the /PRNT signal from the video
controller. Or from the end of the
LSTR period until power OFF.
INTR (INITIAL ROTATION period)	To stabilize the photosensitive
From the input of the /PRNT signal	drum sensitivity in preparation
from the video controller until the	for printing. Also to clean the
end of the APC operation.	transfer charging roller.
PRINT (print)	To form images on the
From the end of initial rotation until	photosensitive drum based on
the motor stops.	the /VDO signal from the video
	controller and transfers the
	toner image to paper.
LSTR (LAST ROTATION period)	To deliver the last page. Also to	The printer enters the
From when the primary high	clean the transfer charging	INTR period when the
voltage (DC) goes OFF until the	roller.	/PRNT signal is sent
main motor stops.		from the video controller.

EN Basic sequence of operation (formatter-to-printer) 83