ACCULINK 3163 DSU/CSU
D-4 March 1999 3163-A2-GB20-10
COM Port Interface
The COM port connects to a PC for front panel
emulation, to an ASCII terminal or printer for alarms, to
an async terminal, to a network device (e.g., a router) for
Telnet applications, to the LAN Adapter for Telnet
applications, or to another DSU/CSU’s AUX port for
daisy chain connectivity. The COM port connector is an
8-position keyed modular connector (Table D-3). The data
signals on this port are referenced to a DTE interface.
The COM port-to-PC cable is shown in Figure D-4 and
the COM port-to-terminal/printer cable is shown in
Figure D-5.
NOTE
For daisy-chaining the AUX port
of another 31xx device to the
3163’s COM port, a
25-pin-to-8-pin cable is required.
The AUX port of the 31xx device
must be set to Daisy and the
COM port of the 3163 must be
set to Mgmt. Whenever the
cable is connected or
disconnected, you should
change the Daisy selection to
ensure that the correct
parameters have been
negotiated for the link layer.
Table D-3
COM Port Connector
Signal Direction Pin Number
DCE Transmit Clock From DSU/CSU 1
DCE Receive Data From DSU/CSU 2
Signal Ground —3
DCE Transmit Data To DSU/CSU 4
DCE Data Terminal Ready To DSU/CSU 5
DCE Carrier Detect From DSU/CSU 6
DCE Request-to-Send To DSU/CSU 7
DCE Receive Clock From DSU/CSU 8