Re: Known-good IBM joystick? (Evan Koblentz)

A quick note on reading the Joystick ports on an Apple II. The circuit uses a RC timer to discharge a capacitor to measure the resistance of the potentiometer (resistor). If you do multiple PDL reads back to back, you may get a faulty reading the second time. This is because the capacitor needs time to recharge before the second read. It's best to put some other code in between the paddle reads in order to give the capacitor time to fully charge. regards, Mike Willegal