Table C-1. Eia-232-D Interconnect - Motorola MVME2603-1121A Installation And Use Manual

Table C-1. EIA-232-D Interconnect Signals
Pin Signal
Number Mnemonic
1 Not used.
2 TxD Transmit Data. Data to be transmitted; input to modem from terminal.
Receive Data. Data which is demodulated from the receive line; output from
3 RxD
modem to terminal.
Request To Send. Input to modem from terminal when required to transmit a
4 RTS message. With RTS off, the modem carrier remains off. When RTS is turned on,
the modem immediately turns on the carrier.
Clear To Send. Output from modem to terminal to indicate that message
5 CTS transmission can begin. When a modem is used, CTS follows the off-to-on
transition of RTS after a time delay.
Data Set Ready. Output from modem to terminal to indicate that the modem is
6 DSR
ready to send or receive data.
7 SG Signal Ground. Common return line for all signals at the modem interface.
Data Carrier Detect. Output from modem to terminal to indicate that a valid
8 DCD
carrier is being received.
9-14 Not used.
Transmit Clock (DCE). Output from modem to terminal; clocks data from the
15 TxC
terminal to the modem.
16 Not used.
Receive Clock. Output from terminal to modem; clocks input data from the
17 RxC
terminal to the modem.
18, 19 Not used.
Data Terminal Ready. Input to modem from terminal; indicates that the terminal
20 DTR
is ready to send or receive data.
21 Not used.
Ring Indicator. Output from modem to terminal; indicates that an incoming call
22 RI is present. The terminal causes the modem to answer the phone by carrying
DTR true while RI is active..
23 Not used.
Transmit Clock (DTE). Input to modem from terminal; same function as TxC on
24 TxC
pin 15.
Busy. Input to modem from terminal; a positive EIA signal applied to this pin
25 BSY
causes the modem to go off-hook and make the associated phone busy.
Signal Name and Description
Serial Interconnections
C-3
C