I bet it is the 74LS245 data buffer right off the 6502's data bus. I
have seen this problem before, it is frustrating. I have even replaced
this chip before pulling RAM's just in case and it has
saved me time before.
jess
MKDUD@aol.com wrote:
>
> Hello,
>
> Please help if you can. I'm trying to fix a BZ boardset. I'm getting
> what would seem to be ram errors for the 2114's at location A1 and A2. (two
> short low tones, followed by two long high tones. Board will not boot,
> nothing on screen).
> I've allready installed sockets and replaced the 2114's, and am still
> getting the same error. I haven't had a chance to check the enable line for
> this Vram pair to see if it is low yet, but I've got a question about the
> roms.
> This board has all roms, except for one Eprom located at A3. The eprom
> is labled 036421. However, there are no solder pads connected for the rom
> selections on this board. Does anybody know what solder pads have to be
> connected if you want to put 2716's in the BZ board? Can I replace all the
> roms with newly burned 2716's?? What changes do I have to do to the pads?
>
> Any help would be appreciated,
>
> Thanks Very Much,
> Michael Kelley
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Received on Mon Sep 25 19:39:25 2000
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