tmariner wrote:
>
> If you really need a modem -- I believe all standards up to 1200 bps require
> no phase decoding and are simple "mark space" FM encoding. We once did a 300
> baud modem with a 5 bit D/A and a zero crossing 1 bit input that was stable
> enough to half-duplex communicate over virtually any phone line with any
> modem. I wonder, however, of the ability of a sound card to continue with
> single tone bursts uninterrupted by the operating system.
>

I don't have the project done yet, but I can couple the input signal to
a gate via a cap and see the output of the gate go up and down, so I
know I can detect the signal. Now all I gotta do is make some sort of
FM discriminator, and I can do that without bogging the chip down -
I'll interrupt drive it, and the ISR is fast except when it realizes it's
gotten a byte.

   ... then it has to reel the fish in.

--
Anniepoo
Need loco motors?
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