hi, i am also facing similar issue. I had installed pci card parallel port, but Mach3 is not communicating it.
I checked parallel port using parallel port testing application and it is working. My driver has 3 leds for each axis and when I connected my 3 axis driver to parallel port and using testing application i can able to blink those led and moreover on switching pin status (very slow pulse) on testing application i can able even able to rotate the motors.
That means testing application is able communicate with driver through parallel port. But when i try to run from Mach3 its not working i had correctly set port address in mach3 which is same i am using in testing application. Is there any driver patch i should try for mach3?
I am using win7.