RE: DAC question

> Yeah, the AD 7528 is a dual 8 bit digital output chip. They are still
> available, but I have a LOT of them and was thinking maybe we
> could use them
> for a diagnostic and trick intro screen for the new monitors,
> have it come
> up on boot, then hand over control to the input bus after a
> set time. They
> are parallel input, and you write to them like memory
> locations! They could
> practically run off an eprom with a clock and an address
> increment chip
> alone, or your cool little micro if it had enough lines.

Yeah... Those would work fine for a built-in test pattern generator or
something. The resolution isn't great, but it's not really needed anyway.
I'd probably recommend just hanging it off a parallel port on the AVR and
let that drive the DACs. Stuff made out of straight lines would be easy
enough to implement. The display couldn't be *too* complex since the AVR
will only be able to drive the DACs so fast, but I'm sure it could put up
test patterns and/or maybe a few letters or something.

-Clay
Received on Tue Nov 16 19:54:12 1999