Re: wanted: Apple II plus Language Card or RAMCARD schematic

["Michael J. Mahon" <mjmahon@aol.com>]

mspangler wrote:
> David Wilson wrote:
>
>
> > The schematic can be found on page 5-27 of "Understanding the Apple II"
> > by Jim Sather (ISBN 0-912985-01-1) - if you cannot source this I should
> > be able to scan it or take a picture of it. It is a bit difficult to
> > describe (and not directly usable unless you intend to use 4116 RAM
> > chips). It would be much simpler to use a 62256 static RAM chip and a
> > PLD - you avoid the need for the cable to the motherboard RAM array.
>
>
> Applied Engineering sold a SRAM based language card. That schematic
> would be useful. For that matter, a new source of IO32 cards (a pair of
> 6821 PIAs and a Rom that I assume had some routines that ran off of
> ampersand routines) would be great too. 

A Mockingboard is a 32-bit parallel I/O card.

There are two 6522's each of which provides two 8-bit bidirectional
ports.  Of course, for each 6522 one of the ports (and a couple bits
of the other) is hooked up to an '8910.

But each '8910 has an 8-bit port, too--accessible indirectly through
the 6522!  (It's not as clever as the 6522 ports, but it's there--
and almost never used.)

Any card with a 6522 on it begs to be used as a timer, shifter,
parallel port, interrupt source, etc.  I find the 6522 much more
interesting than the '8910 it drives.  ;-)

-michael

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

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