Image Memory - Canon GP605 Service Manual

H.

Image Memory

The copier is equipped with the following image memory:
[1] Image server (hard disk)
[2] Memory board (DRAM; page memory)
1. For main scanning direction, control is
based on synchronization with the BD
signal.
For sub scanning direction, control is
based on synchronization with the
PTOP signal (image leading edge
signal generated from the registration
ON signal).
2. Controls the destination of image data.
Memory board
DRAM
Page memory to enable
synchronization of image
signals for each page.
Memory board
Memory board
To laser driver PCB
COPYRIGHT © 1999 CANON INC.
Scanner input
Stores images, and generates a selected number of sets.
Figure 4-306 Image Memory Block Diagram
Image data
Compression
Hard disk
De-compression
Figure 4-307 Flow of Image Data
CANON GP605/605V REV.0 JAN. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 4 IMAGE PROCESSING SYSTEM
CCD PCB
PDL input
Frame erasing
Rotation
Compression /
Memory
expansion
control
Black density
count
Stores images in page memory
once, and waits until the previous
image is compressed.
Develops and stores images in page
memory to enable synchronization
of image signals for each page.
PDL board
IP PCB
Image
processing
MFC PCB
Data transfer
control
To image server
Hard disk
4-17