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Re: Parallel Card

mdj wrote:

Michael J. Mahon wrote:



I suggested a "direct" parallel port approach because 6522
hardware is available already constructed and the programming
is simpler, but there are, of course, many other alternatives.



Sure is, and the device gives you lots of other options to play with as
well.

Every parallel card I have lying around for the Apple II is a 'dumb'
parallel card that implements 8 outputs and a strobe using TTL logic,
plus an EPROM to provide the communications firmware. Still useful, but
crummy compared to a 6522 card.

I guess such cards are still easy to come by, but I admit I've not
really looked.


Although you would have to wire up the ports yourself, the
Mockingboard is a dual-6522 card...for a total of 32-bits of
bidirectional ports!

If you made DIP-plug cables that plugged into the AY3-8910
sockets, you could pick up two full ports (one on each 6522)
without any soldering.  ;-)

-michael

Parallel computing for 8-bit Apple II's!
Home page:  http://members.aol.com/MJMahon/

"The wastebasket is our most important design
tool--and it is seriously underused."