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weird almost Mockingboard semi-clone
- Subject: weird almost Mockingboard semi-clone
- From: Alex Freed <alex_news@mirrow.com>
- Date: Sun, 09 Nov 2008 04:20:46 -0800
- Newsgroups: comp.sys.apple2
- Organization: Aioe.org NNTP Server
- User-agent: Thunderbird 2.0.0.17 (Windows/20080914)
- Xref: g2news1.google.com comp.sys.apple2:4439
I just became a proud but mystified owner of an Apple 2 sound card
that is definitely not MockingBoard compatible even though it has
a 6522 and 3(!) AY-3-8910 chips: the 6522 chips select is wired to
DEVICE SELECT rather than I/O SELECT so it uses a different addresses.
The board has no markings at all to indicate its origin but is simple
enough to figure out the functionality. There is a decoder that selects
one of the 3 AY-3-8910 chips depending on the 6522's PB4 and PB5.
Did anyone ever see such a board?
Should be easy enough to rewire it to be compatible with the one AY
MockingBoard, but before I do - could there be any software around for
this card's native mode? Google didn't find any leads.
-Alex.