2.1Main Control Board (BOARD-FFF)
The control board consists of an one chip CPU,a LSI, program/font ROM's, DRAM's, an EEPROM, a host interface circuit, and a mechanism driving circuit.
(1)
The
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Chip select controller | Control of peripheral LSI, ROM, DRAM and I/O device |
Bus controller |
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DRAM controller |
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DMA controller | Transfer of data from Host I/F to RAM |
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Serial interface controller | Control of RS232C serial interface |
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Parallel interface controller | Control of Centronics parallel interface |
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Timer | Generation of various control timing |
| Monitoring of paper running and paper size |
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Serial I/O port | Control of serial interface between controller and operator panel, EEPROM |
| Control of a serial interface between controller and power supply board |
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I/O port | Inputting of various sensor signals |
| Outputting of various control signals |
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Motor driver controller | Control of Main Motor |
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Image processing circuit | Executes the image data process for printing. |
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(2)Program/font ROM's
•PCL ROM
The program/font ROM's store the HP LJ5 emulation program and various types of font. MASK ROM is used as the program/font ROM's.
•PS ROM
The program/font ROM's store the Adobe PostScript Level 2 program and its fonts.
40930701TH DRAFT Vesion | 16 / |