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New Member

raising DTR & RTS on a serial port

(2)AS5350s connected back to back over a V.35 cross cable. I believe the interface, serial 0/0, configuration is ok but it's not up so all suggestions are welcome. Here is a show status of the interface:

St.Maarten#show interface serial 0/0

Serial0/0 is down, line protocol is down

Hardware is DSCC4 Serial

MTU 1500 bytes, BW 256000 Kbit, DLY 20000 usec,

reliability 255/255, txload 1/255, rxload 1/255

Encapsulation HDLC, loopback not set

Keepalive set (10 sec)

Last input never, output never, output hang never

Last clearing of "show interface" counters 00:01:41

Queueing strategy: fifo

Output queue 0/4096, 0 drops; input queue 0/4096, 0 drops

5 minute input rate 0 bits/sec, 0 packets/sec

5 minute output rate 0 bits/sec, 0 packets/sec

0 packets input, 0 bytes, 0 no buffer

Received 0 broadcasts, 0 runts, 0 giants, 0 throttles

0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort

0 packets output, 0 bytes, 0 underruns

0 output errors, 0 collisions, 3 interface resets

0 output buffer failures, 0 output buffers swapped out

0 carrier transitions

DCD=up DSR=up DTR=down RTS=down CTS=up


In the real world, I will be setting the interfaces up to work over a fractional T1 circuit. Questions I have are: should I be configured for PPP or HDLC or what? Also, How do I raise my DTR and RTS? A big thanks in advance.

New Member

Re: raising DTR & RTS on a serial port

Make sure the cable are correct.

V.35 DTE <--->V.35 DCE

and provide clocking on DCE side. This should bring up the link regardless of its PPP or HDLC. "shut down/no shut down" and it should bring the link up.


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