2.1Control Board
The control board consists of a single chip CPU, Program & Font ROM's, one or two DRAMs, an EEPROM, a host interface circuit, and a mechanism driving circuit.
(1)Single chip CPU
The single chip CPU is a custom CPU
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Chip select controller | Control of ROM, DRAM and I/O device |
Bus controller |
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DRAM controller |
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DMA controller | Transfer of image data from DRAM to video output port |
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Parallel interface controller | Control of Centronics parallel interface |
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Video output port | Control of LED head |
LED STB output port |
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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 operator panel, EEPROM, and options |
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I/O port | Input and output of sensor and motor signals |
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(2)Program & Font ROM OKIPAGE 6e/6ex
The Program & Font ROM store the PCL5e emulation program and various types of fonts. Mask ROM is used for a Program & Font ROM. The mounting location of this Program & Font ROM varies depending on the type of ROM (for the mounting location see 7.2).
PS Board
The Program & Font ROM store the PostScript program and various types of fonts. Mask ROM is used for a Program & Font ROM (for the mounting location see 7.3).
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