HP P3005 manual 1Operation sequences, 2Power-on sequence, Name Timing Purpose, Step Action

Timing

The microprocessor on the engine control unit (ECU) controls the device operation sequences. Table 4-1 Operation sequences on page 58 describes engine operations for each period of a print operation. Table 4-2Power-on sequence on page 58 describes each step of the power-on sequence.

Table 4-1Operation sequences

Name Timing Purpose

WAIT	From power-on until the end of the main motor initial
	drive

Detects presence of a print cartridge. Clears potential from the drum surface and cleans the transfer roller.

See Table 4-2Power-on sequence on page 58 for a complete description of the WAIT (power-on) period. Also see Figure 4-17 Timing diagram

on page 60 for detailed information about device timing.

STBY (standby)	From the end of the WAIT or LSTR period until either	Prepares the device to receive print commands
	a print command is sent from the formatter or the
	power is turned off.
INTR (initial	From the time of the print command until the pickup	Prepares the photosensitive drum for printing.
rotation)	solenoid is turned on.
PRINT	From the end of the INTR period until the top-of-page	Forms the image on the photosensitive drum and
	sensor detects the trailing edge of the media.	transfers the toner image to the media.
LSTR (last	From the end of the PRINT period until the main	Delivers the last page of a print job.
rotation)	motor stops rotating.	After LSTR, the device either returns to STBY or, if
		another print command was sent from the formatter,
		enters INTR.

Table 4-2Power-on sequence

Step	Action
1	Power-on
2	CPU initialization
3	Video-interface communication start
4	Sensors check for residual media
5	Main motor initial drive
6	Fuser heater initial drive. The fuser heater reaches a surface temperature of 120°C.
7	Fuser-motor initial drive
8	Laser/scanner-motor initial drive
9	High-voltage control
	Detection of the presence of a print cartridge
	Cleaning of the transfer roller after the primary charging AC bias is turned on
10	Failure/abnormality check: detection of laser/scanner failure, fuser failure, and open covers
11	Communication with the memory tag

58 Chapter 4 Theory of operation ENWW