wrote in message
news:3991C4E2.C6D2AE0C@com.uncor.edu...
> I am trying to generate a sine wave through the paralell port , but
> Windows generates some delays on it, so the sine is not good. Do you
> know how to sincronize it? or how to makes windows not disturb?
> Thanks
Give up on it 🙂 A parallel port is simply not designed for this, and
Windows is not designed for this. Therefore you either need to build some
kit, or write your own program that takes over the PC at a low level. Since
only your program is then the only thing running in the system, you can
write it in such a way as to guarantee that the correct value hits the
parallel port at the right time, but it'd be far quicker and would make the
code easier to maintain if
you build your own piece of kit to do it if
you're unable to buy a dedicated waveform generator. Obviously the program I
describe here cannot be written in Labview, and cannot interact with Labview
programs or anything else while it runs!
Precisely how you'd go about building it if you choose this approach depends
on what you want to use it for- if you only need a set of specific
frequencies then an analogue sine wave generator circuit with some
components switched in and out by digital switches under the control of the
PC would be adequate. Anything more complex, and you're probably best making
a simple digital waveform synthesiser, that contains a bit of memory, a
counter/timer and a D-A converter; you use the parallel port to load the
memory with your waveform values, some registers to determine the frequency
and the number of samples before the counter is reset (i.e. each cycle of
the waveform) and that's it. If you're well equipped it could be done and
running inside a week- oth
erwise you're delayed by waiting for components to
arrive.
