Oki B 4100 Maintenance Manual page 428

CPU
from PC1
IC2
IOGA
RIINT
from NCU
to Main power supply
(AC ON)
40055101TH Rev.4
R17
CN9
TXD 1 1
2 2
RXD
5 5
OPECHK
PC1-N 13 13
OPERST 4 4
3 3
PSMODE
HUP-N 15 15
14 14
MP/OFF
12 12
Figure A3.4.1 Block Diagram of OPE (operation unit)
OPE (05W) for OKIFAX 5000 series.
X'tal
CN1
IC1
MOS CPU
Internal ROM
Eight LEDs
LEDs
KSCAN0
to
KSCAN7
Key switch
matrix
KSENS0
to
KSENS7
DB0
to
DB7
LCD unit
Control signals
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