Lostgallifreyan wrote:
thanatoid wrote in
:

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.

Some equipment uses 'TTL' levels (0=0.3V and 1=4.7V)

Just FYI, the logic levels are a bit off here. Actually, the TTL logic
levels a

Input: 0 to 0.8 V is a logic low input, and 2.2 to 5V is a logic high
input.
Output: 0 to 0.4 V for a logic low output, and 2.6 to 5V for a logic high
output.