OKIDATA Okipage6e, Руководство по обслуживанию

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Service Guide OKIPAGE6e
Chapter 2 Operation Description
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.
Single Chip CPU
The single chip CPU is a custom CPU (32-bit internal bus, 16-bit or 32-bit external bus, 25.54 MHz clock
with input frequency from a 12.27 MHz clock) which incorporates the RISC CPU and its peripheral
devices, and has the following functions:
Built-in device Function
Chip select controller
Bus controller
DRAM controller Control of ROM, DRAM and I/O device
DMA controller Transfer of image data from DRAM to video output port
Parallel interface controller Control of Centronics parallel interface
Video output port
LED STB output port Control of LED head
Timer Generation of various control timing
Monitoring of paper running and paper size
Serial I/O port Control of operator panel, EEPROM, and options
I/O port Input and output of sensor and motor signals
Program and Font ROM
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).
DRAM
The DRAM is a resident memory (OKIPAGE 6e: 1MB/OKIPAGE 6ex: 2MB) used as a buffer, and it stores
edited data, image data, DLL data and macro data.
EEPROM
1,024 bit-Electrically Erasable PROM (EEPROM), is loaded with the following kinds of data:
Menu data
Various counter data (Page counter, Drum counter)
Adjusting parameters (LED head drive time, print start position, paper feed length)
Parallel Interface
Parallel data is received from the host system via parallel interface which conforms to the Centronics
specification. IEEE 1284 Bi-directional parallel is supported.
Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business
Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com)