Alberto,
If you need parallel output lines, then the printer port seems to be the
only choice,
Don't we still have the problem with Win95/98 very helpfully changing the
port output not-so-periodically if you have a printer driver assigned to the
port. I think, from memory, you need a VXD so that your program
"captures" the port. There was some program/component called something
like "TVich32" kicking around a while ago for this. Another trick that
seems to work is to remove any printer associations via "My Computer".
Win95/98 seems to leave the port alone then. Not likely to be practical
and even less likely to be popular.
In any case it should be possible to latch the the port externally by
decoding a sequence of port writes (to distinguish from Win95/98
interference) as the timing for changing tones is pretty relaxed.
73s Steve
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