Re: 70's Midway board problem

"Christopher X. Candreva" wrote:
>
> On Wed, 24 Apr 2002, Rodger Boots wrote:
>
> > How can you have a bit 12 when it's an 8-bit machine?
>
> Address line ? Even 8 bit machines have a 16 bit address bus !
>
> -Chris

Understood (and you're almost right, unless you have a 2650 processor
like in some Meadows games --- it only has 15 address lines!), but then
how does that become a RAM problem? I know, I know, it's a RAM problem
when it won't respond to A12. But you would think it would flag a
particular BIT failure to go with the A12 failure. And in those games
each RAM only handled one bit.

Unless of course there really is a data line 12 (coming back from the
shifter array), but an 8080 pod shouldn't know anything about that.

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Received on Wed Apr 24 10:40:14 2002