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Jinkle Jose
Cisco Employee

%MAINBOARD-2-INVALID_TXRX: [char] doesn't support different tx speed [dec] and rx speed [dec]

Hi Friends,

%MAINBOARD-2-INVALID_TXRX: [char] doesn't support different tx speed [dec] and rx speed [dec]

    Could anyone explain me what this error message reffers to.

How is Tx and Rx speeds been decided in the interface.?

Can i change them ?

If I can..... how I can change.?

And in what situations I would change them ?

I see that txload 1/255 rxload 1/255 in the show this what its referring to ?

I also see txspeed command in the line configuration.

Why this option is only there in line..... why not in other interfaces ?????????

I know its a lot of questions.........but I m sure it all refers to one explanation.

I dint get any documents or cases which can explain this......

So please do help me.

Thank you in advance



Ivan Shirshin
Cisco Employee

Hi Jinkle,

This message means that you are trying to configure the speed on a async serial interface. When HWIC serial interfaces is operating in async mode, we can not have different txspeed and rxspeed on corresponding line. TxSpeed and RxSpeed need to be same .

Execute "show line to see the tx/rx line speeds. E.g. for 2851 router interfaces Serial0/0/0, Serial 0/0/1:

2851(config-line)#do sh line    Tty Line Typ     Tx/Rx    A Modem  Roty AccO AccI  Uses  Noise Overruns  Int *     0    0 CTY              -    -      -    -    -     0      0    0/0      -       1    1 AUX   9600/9600  -    -      -    -    -     0      0    0/0      - A 0/0/0    2 TTY 115200/115200-    -      -    -    -     0    838 295573/0  Se0/0/0   0/0/1    3 TTY   9600/9600  -    -      -    -    -     0      0    0/0    Se0/0/1

Kind Regards,

**Please grade this post if you find it useful.

Kind Regards,

Hi Ivan,

        So that means, the normal ethernet or serial interface which runs in synchronous mode does not have this tx and rx speeds. Or it is predifined and we cannot change. ?