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

THANKS!

Write @ 0 = FF
Write @ 1 = 00
Read @ 0 return F0

I need to update my manual RAM checker too.

JB

> -----Original Message-----
> From: James S. Bright [mailto:james@quarterarcade.com]
> Sent: Saturday, April 19, 2003 7:34 PM
> To: 'techtoolslist@flippers.com'
> Subject: RE: 9010A, Not sure what this means...
>
>
>
> Thanks. This is very helpful...
>
> JB
>
> --James Bright
> www.QuarterArcade.com
> Restored Arcade Games for your Home
>
>
> > -----Original Message-----
> > From: Mark Shostak (DOS) [mailto:shostak@augustmail.com]
> > Sent: Saturday, April 19, 2003 7:27 PM
> > To: James S. Bright; techtoolslist@flippers.com
> > Subject: 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