Fairlight-CMI

Hi all, new to the group, nice to see an active user base! Been about 17 years since I last 
looked at a Fairlight, but suddenly...

I'm trying to repair a model IIx that will not boot, won't even look at the system floppy, no 
messages on the vdu at all! Initially one of the 6809's was dead, I've replaced that and the 
flat battery on the cpu control card. The vdu progressed from random garbage to a kind of 
ordered garbage, vertical lines and occasionally some text x=ff y=4h c=4a along the 
bottom row, that kind of stuff. That all looks like the screen memory being initialised and 
some further processing being done, which are the duties of the cpu that I replaced.
This was all while it was at the owners studio, so now it's here in my workshop in N 
London and I've made a little more headway. I scoured the service manual for card order 
and discovered that the memory board was in the wrong slot, next to the cpu control 
card, so I've moved this along to the next slot, 14, photo's here confirmed this. Still no 
booting, no red led on the floppy indicating access. 

I think all other cables are in the right locations, could someone confirm the connections 
into the screen card, the connector with 2 cables into the bottom slot?

So I suspect the cpu control card right now, I've run up the dual cpu card on the bench out 
of the mainframe, and it's doing everything the manual says it should, it talks to to the 
control card which supplies startup rom code etc etc accessing system floppy is pretty 
early on in order of things so it's not getting far. Slightly different visual results with the 
control card pulled, but not much.

Can anyone confirm these details for the control card, q133...

f8lmrk5 rom in location d5.6
q9f0mrk1 rom in location c5.6
w1 2 & 3
w2 1 & 2 
w3 2 & 3
w4 2 & 3
w5 1 & 2

Fuses all ok, power rails I can find are +/-18, +/-12,+23,+35,+10 & +5, all these are on 
the spade connectors under the bottom panel. Occasionally I'm getting a failure on -12v 
which clears when I pull cards, lowering the current draw, even rarer I get a failure on 
+12v as well, again pulling cards clears it although it's never the same card, so I suspect a 
intermittent failure in the current limiting there. There were a few faults on the front 
panel, just dry joints though. Three fans, the one directly above the cpu/screen/floppy 
cards is not spinning, so maybe they've baked themselves..I've got it all stripped back 
now, all panels off, seems spiders like it in there, least there were a few cobwebs and a 
few dessicated arachnids :-]

With all cards pulled except memory, cpu, control, screen and floppy controller, only 
screen attached, no keyboards, I'm still not booting...front panel reset button does 
nothing.

I see the eprom images on here, wonderful! I can pop into Funky Junk and checksum my 
set, burn some new ones anyway, I've got heaps of 2716's around from old lexicon 224 
romsets. That's a real help.

Also the vdu has some mottling on the front green screen, has anyone tried cleaning this 
on the inside, or does the green all come off if you do..?

Sorry for the essay people, but it helps to put this stuff down sometimes, and I'm hoping 
you can help out with some details. I've dug around in the messages but not found 
anything pertinent, so maybe I can help contribute with this troubleshooting.

simon, tech.

Hi again, more trobleshooting...

Can anyone tell me which locations the eprom files are for?

I've burnt a set from the images here. All except for the cmikbd, as this seems to run fine, 
displays 'power on'.

The eproms on the cpu control card, easy, f8l in location d 5.6 and q9f0 in location c5.6..

The eprom label on my floppy controller is scratched off, can I assume this is the 
'floppycm' eprom?

The two labelled 2.090 and 2.09e, are these for the cmi 28 card, slot 2? This unit has two 
eproms on that card labelled 'mon 11/10 O' and 'mon 11/10 E' both are 2764's. I've left 
the originals in.

Well the q9fo eprom was bad when I tested it against the image file here, so hopefully 
that's cleared another fault, also my floppy card eprom didn't match any of the files here, 
so it's erased and  'floppycm' burnt to it, tested ok in the burner. My floppy card is a 
'QFC9 rev5'. The f8lmrk5 eprom from my unit checked fine against the file here, so I can 
assume the files are good, has anyone else used the eprom images here to make a fresh 
set?

Anyway she's still not booting, but the display has changed to a solid green screen now, 
no more lines. Progress? I guess so!

Simon