thanatoid wrote:
Hello again,

I have a basic question: is there any way I can damage either
the serial port circuitry OR the MB itself by incorrectly (wrong
pinouts, bad cable, link program doing something to the machine,
etc.) when trying if a DB-9 serial cable with a null modem
adapter will work?

I am asking because my "USB on a 166MHz PI from 1997" experiment
failed - there is no power going to the MB USB port connector
pins - so I have given up. I am interested in trying a serial
cable connection - Total Commander has it built in, and I also
have several other DOS and Win programs for it. But I don't want
to blow up either of the two computers.

Is there any danger?

Thanks.

http://en.wikipedia.org/wiki/RS-232

"Voltage levels

RS-232 drivers and receivers must be able to withstand indefinite
short circuit to ground or to any voltage level up to ±25 volts."

That provides a good deal of protection against mistakes.

Go for it.

On the older RS232 driver chips, the biggest danger, was their lack
of protection with respect to static discharge. Scuffing over the
carpeting, then directly touching the pins, would be a bad idea.

And if you somehow manage to burn that out, there is always the
parallel port :-)

Paul