Re: Apple 2e - building a simple expansion card and calling it from BASIC (or assembly)?

[Mike Willegal <mike@willegal.net>]

I did a camera shutter tester a couple of years ago.

http://www.willegal.net/photo/repair/besttester.htm

Only 3 IC's, though I know now that I could have eliminated the op-amp.

I didn't bother with onboard PROM with program, just hardcoded to slot 4 
and saved several chips.  Making a two sided PC board that would fit in 
the slots wasn't too difficult  (this was my first PCB, ever), but you 
do have to be careful about registration.

Regards,
Mike Willegal


mad.scientist.jr@gmail.com wrote:
> Has anyone built their own Apple 2 expansion card and programmed it to
> do something?
>
> If it wouldn't be ridiculously hard, I would like to try etching a
> circuit board to plug into one of the expansion slots on my 2e. The
> board would contain a single relay, which could be opened or closed
> from BASIC code (or if it is not possible from BASIC, from 6502
> assembly).
>
> I'd also like to have the board contain 2 leads that the computer
> could tell when they are connected together.
>
> Maybe later I would expand the # of relays or leads, or build an
> additional card or two, for more "inputs" and "outputs".
>
> Any information would be appreciated...
>
> Thanks