Re: Poss. dumb 9010 query

Found me "BTS 08" problem, a broken track underneath the 245 at B3.

Now onto a decode error!

On Wednesday 06 July 2005 12:00, Martin White wrote:
> Program ram (a single 6116 on the SCPU board) can't be tested at all. It
> simply can't talk to it properly, nor the roms (so it would seem anyway -
> wander if that's anything to do with the CTC?). It comes up with BTS FF
> error for any address in program ram - a single 6116. This is not a fault
> though, it's just the way it is. It does it on all 15 boardsets i'm working
> on, even the ones where the game works fine and there are just issues with
> the SSIO board!
>
> The staging ram (2 x 2114 on the vid gen board) have the BTS 08 error,
> however, the problem doesn't lie with anything on the vid gen board since
> you can disconnect that board completely and still get the BTS 08 error
> when you try to do the test on the background ram.
>
> I haven't tried removing all the roms to see if they're fouling the busses
> at all, but they shouldn't be since they're known good roms. Could be
> sockets i guess?
>
> So you see, i'm pretty sure i'm looking at a buffer / interface problem,
> just wanting to confirm if it's the address lines or the data lines for the
> particular Fluke error message. I'm pretty sure it's the data lines.
>
> However, i'm not seeing any bit tied high or low, so maybe i'll just
> replace the 245 anyway for the fun of it, and maybe the cpu socket, and i
> guess i can always try removing the pull-up resistor pack on the data lines
> and see if the problem goes away before putting them back of course!
>
> Cheers all...
>
> Martin.
>
> On Wednesday 06 July 2005 01:50, John Robertson wrote:
> > How about trying to test RAM in a different IC?
> >
> > If you have three banks of RAM, try testing each bank to see if you
> > get the problem in one bank or all. One bank is obviously the sick
> > RAM chip, ALL banks would be some interface or timing issue, but if
> > all banks show the same error then pretty safe to be an interface IC
> > issue.
> >
> > John :-#)#
> >
> > At 1:39 AM +0100 7/6/05, Martin White wrote:
> > >Sorry, but i do get rather confused with this thing from time to time
> > > :o)
> > >
> > >I'm getting a "R/W Error @ F800 BTS 08" when trying to test the ram on
> > > one of these MCR boards. Am i right in saying that i need to be
> > > tracking down a problem on the data bus, bit 4, bit 3 if you prefer
> > > your numbers to be 0 based (1000 = 8, therefore, that's bit 0, 1, 2,
> > > then 3 or 1, 2, 3, then 4).
> > >
> > >And if it were a decode error then that would be the address bus?
> > >
> > >I'm assuming all is well with chip selects and r/w signals since it's
> > > only complaining about bit 08 and not FF?
> > >
> > >As an aside, i burnt a set of home burnt roms but the 9010 still can't
> > > read the things reliably in the MCR sets. It doesn't seem to like
> > > anything that's in close relation to the CTC i don't think. It's happy
> > > enough troubleshooting the video staging ram and the background ram,
> > > just not the program ram or rom :(
> > >
> > >I'm using a normal Z80 pod with a Z80A processor in it. I'm guessing
> > > from reading previous posts that there would be no benefit in trying to
> > > blag or borrow a Z80AA since someone else was saying that couldn't cope
> > > with MCR hardware either.
> > >
> > >Martin.
> >
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Received on Wed Jul 06 17:25:01 2005