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Re: How much of a ][ is needed to twitch?
Matthew T. Russotto wrote:
> In article <45ce84be$0$83739$c30e37c6@lon-reader.news.telstra.net>,
> Tristan Mumford <xtristan.xmumford@xgmail.xcom> wrote:
>
-snipped idea of pulling chips to diagnose machine-
>
> This is probably NOT a good way to diagnose the machine. The garbage
> pattern really says nothing except that the character generator and at
> least some of the RAM is working.
>
>>I'm hopeful of a solution that doesn't involve me blindly replacing chips
>>until I find the culprit.
>
> That has a better chance of succeeding. Using a scope or even just a
> multimeter and the schematic will help. First thing I'd check is
> probably to see if the processor is running at all (see if the clock
> phase outputs are changing).
You have a very good point there. At least finding whether the 6502 is
receiving the signals. Because one thing I can say is the CPU actually
being in the motherboard makes no visible difference. Ie I pulled it and it
didn't affect the garbage.
If the CPU is fried it's a nuisance but no big deal. The 65816 should work,
and they are relatively inexpensive (although it would probably be a few
months before I could get even that).
I wish I had a scope. Kind of makes me wish I could do some kind of
space/time teleport trick. When i was living in near melbourne there was a
small pawnbroker that had the strangest stuff. Including about 6 CROs.
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