ACCULINK 316x DSU/CSU
D-6 January 1997 3160-A2-GB21-50
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
SNMP or Telnet applications, to the LAN Adapter for
SNMP or Telnet applications, or to another DSU/CSU’s
AUX port for daisy chain connectivity. (The SNMP LAN
Adapter includes the cable that is needed to attach it to
the DSU/CSU.) The COM port connector is an 8-position
keyed modular connector (Table D-5). The data signals on
this port are referenced to a DTE interface.
The COM port-to-PC cable is shown in Figure D-5 and
the COM port-to-terminal/printer cable is shown in
Figure D-6.
NOTE
For daisy-chaining an AUX port
to a COM port, a 25-pin-to-8-pin,
cable is required and the
appropriate configuration
options (Com Use and Aux Use)
must be set to Daisy. 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-5
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