Cabling Requirements 1-9
Cabling Requirements
Cables to connect the 3Com Impact digital modem to your
computer are provided. For IBM or IBM-compatible PCs with
a 25-pin serial port, a DB-9–to–DB-25 connection adapter is
included with the digital modem.
The asynchronous RS-232-C port on the digital modem,
labeled Computer, is a standard DB-9 female connector. The
digital modem asynchronous port pin assignments, shown in
Table 1-2, conform to standard definitions for data
communications equipment (DCE).
Table 1-2 Pin Descriptions
Pin # Pin Name Signal Direction
1Carrier Detect (DCD) From digital modem
2 Receive Data (RD) From digital modem
3 Transmit Data (TD) To digital modem
4 Data Terminal Ready
(DTR)
To digital modem
5 Signal Ground (GND) —
6 Data Set Ready (DSR) From digital modem
7 Request to Send (RTS) To digital modem
8 Clear to Send (CTS) From digital modem
9 Ring Indicator (RI) From digital modem