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micro
09-15-2007, 09:00 AM
Guys, in my Linux (and Windows) experience I found out that in times of a network failure, instead of cursing and disconnecting monitors to put them to the server, we can simulate a dumb terminal in our desktop simply by interconnecting the two computer serial ports. I did this, so in case something goes wrong I can use Putty (for windows) or minicom (for Linux vt) or even telix in a dos boot disk in my main workstation. And I do not have to get up to issue command to the server's keyboard. So I did it. My questions are these:

When I bought the cables the seller asked me "inverted or straight?" I figured inverted but took both. In my haste, I put them to testing and now I don't remember which is the right, in case someone asks me. The cables do not mention the inversion like the ethernet ones do. Which was the right one?

The terminal assumes 80x25 and Putty does not give another dimension to the terminal server; is this normal?

Some special keys do not function but the esc-number sequence is functional. Which number corresponds to the F10 key (i.e. to close mc)?

9800 baud rate is the default, but i think that serial ports are faster in general. Up to which number can I adjust the speed in both server inittab and putty configuration?

Oh, btw thank god of unix the inittab lines were there commented. I would spend all day to make this work if they weren't there.

michaelk
09-15-2007, 10:22 AM
A null modem serial cable is similar to an ethernet cross over cable in function i.e. the TX and RX are pins (2 & 3) are crossed. Therefore, when connecting two computers together you need to use a nulll modem cable.

The max baud rate depends on the serial port hardware (UART) of the computer. 115,200 is typically the max these days but there are faster. Both computers have to be configured the same. Cable length can effect speed and if you are see errors then slow the baud rate down.

micro
09-15-2007, 12:34 PM
Thanx. I have made the screenshot of the serial dumb terminal emulation in my page. Leaving the baud rate to the low level makes the terminal to behave as if it were an old real one and this is kind of funny. I will leave it like this for the moment.