General Category > Lisa Troubleshooting and Repair

And so the Lisa adventure begins

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blusnowkitty:
So I actually got things in a slightly better shape a few days ago but I didn't want to triple-post.

I must have gotten some jumper wires mixed up somewhere along the line. I pulled off all the jumper wires except for the one going from the 7417 to the COP421 and then the Lisa actually started to power up again. The recapped supply was still clicking but I gave R29 a dose of Deoxit and tweaked the pot and so far it's been going alright. I also figured out that whatever was going on with that burned coil probably hasn't hurt it too bad as tweaking and throwing some Deoxit in all the video pots got the video more or less working. I am now having an issue with the screen being "wobbly" - turns out someone else on 68kmla is having the exact same issue: https://68kmla.org/forums/index.php?/topic/59382-lisa-ac-interference-coupling/

As far as the I/O board goes - thankfully the COP421 appears to be working as even though I bypassed its soft power ability, I'm still getting mouse and keyboard input. However, disk access isn't working as I'm getting lots of Error 39 and Error 57 messages on POST. I also noticed that with the original drive ROM the Lisa would sometimes identify it correctly as A8, but more often than not wouldn't read it properly and throw any random hex value from 00 to FF up on the screen. I replaced the ROM with one I burned from Bitsavers and now it's reading it as A8 every time, but I'm still getting 39 and 57 errors. All socketed ICs were removed and sprayed with Deoxit just to be on the safe side and there's been no difference. I've also noticed that with either drive ROM a lot of times the Lisa will think it's somehow become a Twiggy machine again and will show two floppy drives in the startup menu, even though I'm running F/A8 or H/A8 (I have both). Finally as a further troubleshooting aid I hooked up my Floppy Emu in Lisa mode and I've discovered that most of the time the Lisa will make absolutely no attempt to read a disk. Sometimes during POST, however, the Lisa will pull the Read line active but it still makes no effort to actually read a disk.

Motherboard-wise, I also hit it with Deoxit just to be on the safe side but my motherboard surprisingly it was largely spared from battery damage as all the I/O board contacts and solder joints have perfect continuity everywhere they're supposed to go.

I'm sure it's probably a case of corroded traces causing the disk access issue, but as I have no test equipment besides a basic Hazard Fraught Tools multimeter, I thought it would be better to get a known good I/O board to work with. Later on I can come back to the original I/O board once I have better test equipment and take a real deep dive into exactly what's going on.

blusnowkitty:
New I/O board came in today and here's where things get interesting. Plugging the new I/O board in causes the built-in monitor to stop displaying an image, but I get an image off the video out port. Plugging the old I/O board in causes the built-in monitor to work again. Any tips on what I should check out?

As it turns out I'm the idiot here - I forgot I adjusted the analog board's contrast level for the old board and it wasn't right for the new board.

Now I'm trying to figure out why the floppy isn't reading correctly. On both a known good 400k drive and a Floppy Emu it'll make some attempt to read the floppy (or format) but it eventually just gives up and says there was an error. I also can't get BLU going again so that's fun.

Update: Now I got BLU to load. If I try to format a floppy, I get Error 15 from the controller. If I try to read a disk into memory, I get Error 17.

blusnowkitty:
One more little update here... It appears to be fully working electrically now! Just had to reseat some chips and I got serial and the floppy drive working. Here's the rundown of what I've done to get it up and running:

- Installed new I/O board (Would have redone the old one, but I lack the necessary tools to do a deep investigation into it)
- Installed X/ProFile
- Recapped PSU
- Recapped analog board, plus resoldered all the joints as something was dry and causing video glitches
- Heavy dose of Deoxit in the analog board pots to clear up the contrast smeariness
- Disassembled and relubed floppy drive

All in all a fairly easy job, just time-consuming. Now I have a fully working 2/5 running Office System 3.1 with the full suite of LOS Apps, plus the third-party Phone Dialer (what's it even dialing, anyway?), Calendar, and LabeList. Any more Office System software out there?

stepleton:
There aren't many Office System apps out there. The Lisa was designed with the idea of giving its buyers most of what they needed in one go---at least, I seem to remember Larry Tesler saying something like that in this video.

This didn't stop people from making a few apps here and there. Some of them are on bitsavers.

If you'd like to explore the Mandelbrot set very, very slowly, you can try out my LisaMandelbrot program. This has been written using the QuickPort library, a convenience library for turning full-screen Lisa programs that usually run in the Workshop into applications that can run under the Office System. As such, it's not very good.

If you're really feeling ambitious, you could try writing your own full-featured app using the Lisa ToolKit. The ToolKit (documentation here and here) even comes with about a dozen example apps that demonstrate some of the ToolKit's features and operating principles. They're not all that interesting, but one of them is a little piano keyboard that makes little beeps, which is fun...

blusnowkitty:
ToolKit seems fun; I've been trying to figure out how to get that to install properly in LisaEm for a little bit. I figure the Lisa and my Mac 128 is a good place to get to grips with 68000 assembly, and I've been working with C# enough to kinda get OOP; Lisa Pascal/Clascal just seems like a more archaic form of that.

I have some big plans for this thing...

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