Oki OKIOFFICE44 Service Manual page 272

A3.1.8 R44 Circuit Diagram
1. Block diagram
The circuit diagram consists of the following connectors:
• Connector CN10 that provides an interface between R44 board and NCU board.
• Connector CN3 that provides an interface between R44 board and external electro-mechanical
components (PC1 and PC2).
• Connector CN4 that provides an interface between R44 board and OPE (O4W) unit.
Figure A3.1.8 shows an interface between R44 board and NCU board.
Figure A3.1.9 shows an interface between R44 board and OPE unit.
Figure A3.1.10 shows the related signals of PC1 and PC2.
2. Function
1) External status supervising interface (PC1/PC2)
External status is detected by the photocouplers (PC1/PC2) in the mechanism and the
signal is output to the input port of CPU via this interface circuit.
• PC1: Presence of document on hopper.
• PC2: Presence of document at scanning position.
3. Others
NCU interface signal
• CML
• DP
• SR
• MUTE
• PP
• PBXE
• OH2-N
• OH1-N
• RP
• RI
• S
• R
OPE interface signals
• TXDOPE
• RXDOPE
• OPECHK
• OPERST
• WAKEUP-N
Board Descriptions
When sub-power supply is applied to the fax machine, this signal is output to
OPE unit which will control the main-power supply.
: Line seizure control signal
: Dial pulse control signal
: Control signal for connection between LINE and TEL terminals
: Control signal for pulse dial improvement and bell shunt relay
: Relay control signal for special service code detection at parallel pickup or
remote reception
: Control signal for connecting one of LINE terminal to the PBXE terminal
: Detection of off-hook of terminal connected to TEL-1 or TEL-2
: Output upon circuit current detection after fax line seizure
: Receiving sensitivity determination terminal
: Ringing detection signal
: Send signal (picture data/protocol/tonal signals/PB tone etc.)
: Received signal (picture data/protocol/tonal signals etc.)
: This signal transmits sequentially the contents of each data of TXD (LED
on/off information, etc.) to OPE in serial data from CPU.
: This signal transmits sequentially the contents of each data of RXD (key
code information, etc.) to CPU in serial data from OPE.
: Use to monitor the operation of the OPE unit.
: Reset signal for OPE unit
: Wakeup signal
A - 30 OKIOFFICE 44 Serv. Man., P/N 59276801