Re: "Spy'ing" characters sent thru serial port ?

[Paul Rolland]

Hi Jeff,

> I don't have any software answers, but it sounds like the modem is an 
> external type connected by RS232 cable to a serial port.  RS-232 is 
> pretty simple at the hardware level and you should be able to create 
> a "Y" cable that "sniffs" the transmit from the computer to modem 
> line without interrupting the dialogue between the serial port and 
> modem. Just connect the transmit and signal ground lines to the 
> receive and signal ground lines of a serial terminal or another 
> computer with some terminal software (or even "cat </dev/serial1" or 
> similar) listening to the serial port.  Back in Ye Olde Days (1980s) 
> we used to diagnose modem problems like that all the time.

Sure, that's what we did... provided you have a physical access to
the machine to install such a cable and a second machine... 
But as my only real access is thru an Ethernet cable, I was trying to
identify a software solution.

However, it looks like we're gonna have to go to yours, and try to 
find a way to access the machine physically... 

Thx,
Paul

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