Re: 9010A, Not sure what this means...

If I read your question correctly,

It's complaining about an address decoding error, specifically with bit A0.
So, it found that when it wrote a value to an address, then changed bit A0,
the value it wrote to the previous address appeared at this other address.

Try your manual test again:
write 55 to 0 (and read back)
write AA to 1 (and read back)
read 0 again and see if it's 55 or AA
also try it the other way (if writes to loc 0 appear at loc 1)

That's the basic idea. Bit 0 is about the easiest one you could have hoped
for to learn on. Hope that helps.

-Mark

>
>
> Working on a Centipede (6502 based).
>
> RAM test (Short or Long) on RAM that I think is good, I get "RAM DCD ERR
> @ 0000 BIT 0". I'm not sure what this means. I've tested the buffer
> chips (data and address) and they appear to be okay. When I run custom
> tests (reading and writing AA/55), the RAM seems okay. Can anyone
> elaborate on this error message? The manual didn't really help out. I'm
> not exactly sure what to do next with this board.
>
> (This board doesn't play blind, and nothing appears on monitor.)
>
> TIA.
>
> JB
>
> --James Bright
> www.QuarterArcade.com
> Restored Arcade Games for your Home
>
>
>
Received on Sat Apr 19 19:05:08 2003