Re: [CAD_CAM_EDM_DRO] Re: Black box

Art Fenerty wrote:

> Actually, thats how master control works. It creates a bit stream and
> then
> streams it out. The problem is to interupt windows to do it in the
> background. I think I have found a way and am working on it now. The
> sound
> card in most computers has a DSP chip which can be programmed from 1hz
> to
> 100khz and will interrput the processor at
> that rate. My thought now is to have an application create the bit
> stream
> and then use the DSP interrupt to send it out. I don't see why it
> can't work
> just like real audio, instead of the speaker send it to the printer
> port.

I don't think this is an interrupt, it is a DMA transfer. That's how
.wav files work. If you had a timing chip connected to the parallel
port, it could acknowledge the DMA transfer of a byte every
10 uS or so, that would get you a 100 KHz granularity, and not
too much overhead. For a simple test, this could be just a
one-shot.

Jon