Re: It's time 2 play "ID This Card"!

[mjmahon@aol.com (MJMahon)]

edhel@bigfoot.com (Edhel Iaur, Esq.) wrote:

> My wild & crazy guess is that this is a DAC board ;)  Buuuuut, what
> does this card do?

You got it--it's a DAC board, Digital-to-Analog Converter, that is.

If you poke/store bytes to its slot address (probably C0x0 or Cs00,
where x = slot#+8 and s = slot#), a voltage will appear on the ADC out
line that is approximately (value you stored)/255 * 5 volts.

The output is also amplified/buffered by the '386 audio amplifier, so
it should be good for sampling frequencies up to 50 KHz or better.
That amplifier is commonly used to drive a speaker, too.  You could
try pumping some digitized sound through it at, say, 11.025 KHz
and listen to the output.  The "rheostat" is probably the volume
control.

-michael

 Email:  mjmahon@aol.com
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