Toshiba 4580, Service Manual

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6570/5570 IMAGE PROCESSING 6 - 8 Mar. 1999 © TOSHIBA TEC
6.4 PLG Board (PWA-F-PLG-300)
6.4.1 Features
(1) The image processing ASICs are controlled by CPUs mounted on the PLG board (PWA-F-PLG-300)
and the LGC board (PWA-F-LGC-300).
(2) The image processing functions of the PLG board work to accomplish the following:
•
Smoothing processing
•
External input system interface
•
Image area control
•
Laser related control
6.4.2 Functional description of the image processing circuit
An image processing ASIC of the PLG board works to accomplish the following:
(1) Smoothing processing
This function works to eliminate jaggedness occurring on character edges of images input from the
external input system interface for smooth image output.
(2) External input system interface
This function works to control the input interface to the SYS board (PWA-F-SYS-300).
(3) Image area control
This function works to set the effective image area of four directions of output image.
(4) Laser related control
This function works to control the DAPC (Double Auto Power Control) and to adjust the multiple laser
beam position.