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If some maniacs out there are making DOOM run on an 8088, then sure, why not go for the 68000? You might achieve "frames per minute", but even so.

I think you will need to brush up on your 68000 assembly for that. I can tell from your posts that you've already got your hands on the hardware reference manual (my favourite copy is this one, which may be newer than the one on Bitsavers; all my section and page citations will refer to this...

I've been monitoring your thread for a while :) Any Lisa cloner I discover on Mastodon gets automatically followed. I liked the idea of the kb/power switch/etc. PCB you made. The method you're undertaking of working backwards from the boot ROM source is the approach I would pursue, but I can...

I am not so sure... it wouldn't be possible to adapt a serial mouse without electronics. Bus mouse yes: a port adapter with wires in the right places is very likely to be all that's required. For an old serial mouse, you'd either need to do surgery on the mouse itself to recover the quadrature...

"Macintosh XL" is a term with complicated meanings: that is, it was a marketing term :) At one point Apple sold Lisas running the MacWorks software (but with no hardware changes) as Macintosh XLs. My Lisa 2/10 is this way: its owners manual has a sticker of a Lisa rendered in the Macintosh...

To spell it out: the 6100 will not start at all on a dead battery. Yours may be well on the way out...

These are great explanations about quadrature encoding! One thing that might help you find mice that are easy to adapt is to search for "bus mouse", which was one of the earliest kinds of mouse for the PC. These also use quadrature encoding, and adapting them to a Mac will probably just involve...

I wonder if it would be useful to know which computer magazine it was that the owner worked for? Maybe this device turned up in an article. In fact, if it was built with hot glue, maybe it was a prop they made for a graphic.

Can also report disaster ELNA "Long Life" caps in a NeXT monochrome display. A real mess.

Yes, that should work.

There is a Widget hard drive inside. Can you hear it spin up as you turn on the computer? How far does the computer get after you turn it on --- does it boot into an operating system? Does the little light at the bottom right corner of the grille blink? Given the "help" cards that slide out...

Looks like a pretty standard Lisa 2/10 to me, so no "L@@K PROTOTYPE STEVE JOBS" with this one. Not a converted Lisa 1 either. More pictures will be helpful to see whether you've got something that was cobbled together from parts or sold as a single unit. What does the back look like? What's...

Some plastics can change shape over long intervals, and if parts of the Portable hinge have changed size by even slight amounts, it could become much harder for the hinge to rotate. I don't know how likely this is in this case, but I wouldn't be ready to rule it out as a possibility yet.

If you count the Macintosh XL (i.e. the Lisa) in that list of 68000-powered Macs, there were several OSs: at least two Unixes, the Lisa Office System and Workshop of course, and the Monitor.

Capacitors are one way that video boards can fail, but I've seen other failure mechanisms, including the trimpots going bad (maybe contact cleaner helps?) and some critical diode failing (the analogous diode on a classic Mac analog board is bigger). Be prepared for your recapping not to solve...

I'm confused again --- I thought we had said that READ was stuck on the bad board. Here's where I got that from: Is it the case that READ is not stuck anymore? Or you are saying READ is stll stuck on the bad board, but it looks to you like there's a different reason for it than U8C? I'm sorry...

Congratulations again! The situation you're observing with the noisy bearing is familiar to me, but I'm not so confident in my knowledge here. All I know is limited to observations that I've encountered occasional squealing from bearings before --- usually in ProFiles, not Widgets --- and I...

Thanks for answering all of the questions. You are getting a lot of practice desoldering DIP devices from mid-'80s 4-layer circuit boards! Regarding pin U8C: very interesting, but very confusing! If pin 19 is LOW, then U8C should be passing (well, after inversion) READ through it: if you don't...

Is that Office System 3.1B booting from your Widget? If so, wow, congratulations! Well done --- repairing a Widget is an accomplishment! I've never measured the temperature of any of the Widget components before, but assuming the indications are in degrees C, it doesn't seem too bad. The...

Thanks to your investigations, we are running out of obvious answers for why UA9-UA16 are behaving strangely. This is turning out to be an "interesting" problem :) We've validated your 68000s --- these appear to be fine. There's nothing obviously wrong with the circuit traces for the signals...