Parallel port bidirectional programming.

[Ravaner]

Hello. For a while I use Centronics parallel port to enter digitized data in my very old computer (300 MHz). I use Win-2000 + UserPort in assembly language. Unfortunately my old computer is dead and I replaced it by a "new" one Compacq 733 MHz. Parallel port is in ECP mode, every thing works except that it refuses to work in bidirectional mode (cmd bit b5 inefficient) and so I read what I previously wrote on data register. How must I do to retrieve normal bidirectional way for data ?

 

[berkeman]

Hello. For a while I use Centronics parallel port to enter digitized data in my very old computer (300 MHz). I use Win-2000 + UserPort in assembly language. Unfortunately my old computer is dead and I replaced it by a "new" one Compacq 733 MHz. Parallel port is in ECP mode, every thing works except that it refuses to work in bidirectional mode (cmd bit b5 inefficient) and so I read what I previously wrote on data register. How must I do to retrieve normal bidirectional way for data ?

Can you upgrade to a more modern USB-based data acq approach? I'm surprised you were able to find a PC with a parallel port at all...