13 Aug
2004
13 Aug
'04
6:27 a.m.
From: "Dave Dunfield"
<dave04a(a)dunfield.com>
---snip---
Any further ideas?
Hi Dave
It still sounds like a RAM related issue. The 6502's
needed to gate the VMA with Phase2 ( as I recall ) to
get clean address selects. You might put a scope on
this circuit and make sure it looks like it is working
well.
You should try to create a more exhaustive RAM test.
Although, time consuming, GALPAT is just about the
most intensive.
Dwight
Regards,
Dave
--
dave04a (at) Dave Dunfield
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