Oki B 4100 Maintenance Manual page 404

A3.2.2 M17 Circuit Diagram (Page 2/17)
1. Block diagram
The circuit diagram shown on page 2/17 consists of an input/output gate array IC2 (IOGA3).
Figure A3.2.2 shows the related signals of IOGA3.
2. Functions
IOGA3 is newly developed LSI for scanning and printing control of OKIFAX 5000 series.
IOGA3 contains the following functions:
• Strobe signals control for LED head
• Smoothing control for printing data
• Interface of the peripheral LSI and CPU
3. Others
1) The route to transfer print data to the LED head is follows:
• Data bus route: RX, Memory, Report mode, etc.
2) System clock (CLK) is divided by IOGA3 and these divided clocks are transferred to the
IEXSEED (IC20), LED head and 2'nd tray.
Data/address bus
Data/address bus
Various sensor
40055101TH Rev.4
IOGA3
AD00
to
AD15
Data bus
System clock
(20.000 MHz)
Peripheral control
1284 control
CS generation
I/O port
Printer control
OST-EX
Buffer 640 bytes
Decompressed
(RLE, TIFF, ACC32)
200-300/300-200 con-
verter
High-voltage control
smoothing
Figure A3.2.2 Related Signals of IOGA
HDATA
HCLCK (6.67 MHz/10MHz): to LED head
OPCLK-N (156.25 kHz): to 2'nd tray
1/2
2/2
DRV
DRV
CTR
Bi-Centro
I/F
OPE unit
2nd tray
Speaker
LED head
Fan
M D-motor
M R-motor
Power supply
unit
404 /