Electric Circuitry; Figure 35. Signal Flow Between The Output Device And The Video Controller - HP Color LaserJet 9500 Service Manual

Electric circuitry

A 16-bit microprocessor is installed on the finisher controller PCB to control the finisher operation
sequence and the Jet-Link communication with the video controller PCB.
The finisher controller PCB drives solenoids and motors in response to the commands that the
video controller PCB sends through the Jet-Link communication line. The finisher controller PCB
also reports information about sensors and switches to the video controller PCB through the Jet-
Link communication line.
The following are important functions of the IC chips that are installed on the finisher controller
PCB:
Figure 35. Signal flow between the output device and the video controller
ENWW
IC21 (CPU): controls the operation sequence
IC25 (EEP-ROM): backs up the adjustment values
IC23 (flash memory): stores sequence programs
IC1/IC4 (communication IC): communicates with the printer
Chapter 5 Theory of operation 73