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Synchronous/Asynchronous Communications Port
Synchronous/Asynchronous Communications Port
Synchronous/
Asynchronous
Communication
Port Diagram
Figure B–2 shows the pin layout for the synchronous/
asynchronous communications port.
Figure B–2 Synchronous/Asynchronous Communications Port
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MLO-008585
Synchronous/
Asynchronous
Communications
Port Pin-outs
Table B–2 describes pin usage for the synchronous/asynchronous
communications port.
Table B–2 Synchronous/Asynchronous Communications Port
Pin-outs
Pin Source Signal CCITT
1
EIA
2
Description
1 GND 102 AB Signal ground
2 System TX 103 BA Modem transmitted data
3 Modem/printer RX 104 BB Modem received data
4 System RTS 105 CA Request to send
5 Modem/printer CTS 106 CB Clear to send
6 Modem/printer DSR 107 CC Data set ready
7 GND 102 AB Signal ground
8 Modem/printer CD 109 CF Carrier detector
1
International Telegraph and Telephone Consultative Committee (CCITT), an
international committee that sets international communications standards.
2
Electronic Industries Association
(continued on next page)
Port Pin-outs B–3