27 May
2003
27 May
'03
11:03 a.m.
Hi,
I've just finished fixing the Ace's PCB using wire-wrap wire. All the
broken tracks I've managed to find have been fixed and all the damaged
through-hole plating has been repaired. Except there's one problem. The Ace
*still* won't boot to the FORTH interpreter.
Argh!. There aren't that many chips in the machine...
There is a load of garbage on the display - this
seems to change while the
Garbage as in random dot patterns, or garbage as in characters? Is it
loading the character generator at all?
machine is running. The power consumption of the board
- CPU and all - is
around 800mA (according to the crappy meter on my Farnell 1A bench PSU). I've
DOesn't sound excessive...
got the output on the PSU set to 9V, no current
limit.
Does anyone here have a logic analyser or microprocessor debugger that I
could borrow for a few days? I've got two scopes (a Tek 466 and a Gould
Where are you in the country? I am not lending out any of my test gear (I
depend on it too much!), but if it's physcially possible for us to get
close together, I can have a quick look and wave some probes over it...
OS1100) and a Fluke 25 multimeter, but that's
about it in terms of test
equipment.
Alternatively, does anyone know if a diagnostic ROM exists for the Ace?
Something that would replace ROM A and just load the video/font RAM with the
usual Ace character set would be very handy.
I believe the normal ROMs do that early on anyway.... I've never heard of
a diagnostic ROM for the ACE
The 2114Ls I'm using appear to be OK, but they
draw a lot of current - in
the region of 75 to 100mA each.
YEs, they do eat current...
-tony