Tony Duell wrote:
>> The only "interesting" thing is that the current draw is around
>> 500mA with everything except one of the RAMs and the CPU fitted.
>> With the CPU (a
> Can I assume you've not tried replacing that RAM yet?
No, I've removed it from the board and re-tested the Ace, but all seems well
now.
I've got a 2114 in an old Commodore 64. I can justify pilfering parts from
it because the PSU brick blew, the keyboard is shot and C= sold about a
million of the things anyway (at least 500,000 should still be around,
perhaps in people's attics). I'll buy one off Ebay if I feel like it, but
Commodore machines don't rank high on my "wants list". I'm tend to aim for
British-designed machines, i.e. Sinclair ZX80, ZX81, Acorn BBC series, etc.
Anyone here selling a ZX81 or ZX80? They seem to be extremely rare in my
neck of the woods (West Yorkshire, UK).
BTW, anyone got a pinout for the User Port (the smallest edge connector) on
the Jupiter Ace? It's not mentioned in my "Jupiter Ace FORTH Programming"
manual. I'm assuming that the FORTH Programming manual was the only manual
bundled with the machine because on the first page it carries the usual "TV
goes to mains and Ace, PSU goes to mains and Ace" diagram (VERY similar to
the ones I've seen in Sinclair manuals).
I'm also trying to track down some edge connectors for the bus port on my
Sinclair Spectrum +2A, a disc controller and drive for same (unless the
controller works with PC-style 3.5" drives) and an edge connector for the
Bus port on the Jupiter Ace. Anyone know of a source for any of these items?
> I wonder if at
> least one of the other RAMs (in the video circuity) has also failed
> and is drwaing rather too much current. That probably wouldn't lock
> up the bus, so the machine might appear to do something sane with
> that fault.
Sounds plausible. I'm going to see if I can get the 2114 out of the C64 and
then try it in the Ace (in a socket). That should give me some idea as to
the state of the rest of the circuitry. I don't fancy removing ICs
willy-nilly just to see if they're drawing excessive current. I consider
that to be worse than shotgunning.
Later.
--
Phil.
philpem_at_dsl.pipex.com
http://www.philpem.dsl.pipex.com/
Received on Sat Dec 07 2002 - 02:15:01 GMT