Epson ColorCopy Station 8200, Service Manual

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EPSON Color Copy Station 8200 Revision A
Operating Principles Operating Principles 35
GENERAL DESCRIPTION OF THE BOARD FUNCTION
o
The board processes image data sent through PCI bus, and stores
the image processed data to the SRAM (total memory: 1Mbit)
mounted on the board. (DMA IN)
o
The board sends on the image processed data to the printer through
Super I/O. (DMA OUT)
ECP board processes image data by BILL (bill recognition circuit), TET
(Text Enhancement Technology), MOIRE (deleting moire),
SHARPNESS (emphasizing edges), CMM (changing color). Each
treatment does not support all resolution power. The table below shows
whether respective treatment is valid at each resolution power.
Table 2-1. Resolution Power of Each Treatment
Note: *
¡
: supported x: Not supported
** Resolution Power: main-scanning x sub-scanning
(): when using processing by-pass
As shown in the table above, when using A3 wide (600 x 600 dpi), the
ASIC (TET, MOIRE) treatment on the board are not supported, and
therefore it is supported by software. When the software is used to
process image data, in order to prevent input of the data processed by
TET and MOIRE against BILL (for processed image data cannot be
input to BILL), PCI output is provided with two types of strobe signal.
When performing this process, the software should alternately transmit
one line data processed by TET and MOIRE to PCI.
FUNCTIONAL EXPLANATION
o
PCI:
Controls PCI BUS, LOCAL BUS, and RGB BUS.
o
BILL (Bill recognition circuit):
BILL uses CPU, ASIC, and the program and data stored on the ISA
board. When the system started, the programs and data are loaded
and stored in the DRAM inside BILL. The image data is input
through RGB BUS, and in case BILL recognizes it as a bill, BILL
informs this by interrupting into the LOCAL BUS.
o
TET (TEXT ENHANCED TECHNOLOGY):
Performs TET process.
o
MOIRE:
Performs MOIRE clearing process.
o
SHARPNESS:
Performs edge emphasizing treatment.
o
CMM:
Performs color translation process from RGB TO R’G’B’.
o
DMA:
Storing data sent from CMM in SRAM. (DMA IN)
Four 32Kw x 8bit SRAMs are mounted and total memory amounts
to 32Kw x 8bit.
Resolution
Power** (dpi)
BILL TET MOIRE
SHARPNESS
CMM
300 x 300
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600 x 600
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x*(
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