>Some implementations don't allow reads from the control port though.
I can read from the control port in Windows 98 S.E.
Also I know I can tie the control port directly to ground. I am an
electrical engineering major at University and we have gone over the
internal workings of the parallel port. The dangerous thing to do is set a
pin low and then put +5 volts on the pin (without anything resisting the
current). What happens is the Open-Collector transistor inside tries to
sink too much current and with a small puff of smoke your parallel port
stops working. :) Pulling the line low is a different story. Internally
there is a 4.7 Kohm pull up resistor. This prevents too much current from
flowing.
Still, I have learned in my class that you can read from the control port
(which works in windows, and seeing it is based on hardware... I would not
think that this would be different in windows!) So I am rather confused.
-- To unsubscribe, send mail to: linux-parport-request@torque.net --
-- with the single word "unsubscribe" in the body of the message. --
This archive was generated by hypermail 2b29 : Fri Apr 07 2000 - 07:46:58 EDT