hi..
it has been a year since i last posted a msg on that forum!! pff!
i allready quite experienced in sending data to the 8 output pins of the parallel port, but, i want to use the 5 input pins to send data to the computer, how to design the circuit the would simply contain 5 swithces the send 0 or 1 to each of the 5 input linnes?
do i have o take the power from an external battery or take it from controle pins (1, 14,16,17) ???
No power required.
You just nead to earth the input pins with a resistor of less then 560ohms to activate it.
eg. connect a resistor between pin 10 and the earth pin.
your software will then nead to detect wich pin is earthed.
You may use outputs from the Blue D0-D7 or C0-C3 to flick on a switch or relay which will earth out the red input pins.
The red pins are the input pins.
(dont use pin 15 as it is opposite and it does not seem to work on my computer