Recent content by trag

Regarding making more ROMs: 1) Should I start a second thread to handle the logistics? 2) I suspect I should wait a little while so folks can digest @ClassicHasClass 's information. Some folks may want 2.0, others 1.1.20.1 or both and deciding may take a bit. 3) There will be no...

On any of the X100 family, I strongly recommend installing Connectix's Speed Doubler. Apple had not made the 68K interpreter caching at that point and Speed Doubler delivers a very substantial improvement in performance.

Well, pin 33 on all four chips is definitely tied to a thicker trace and via as is typically used for ground or power plane connections. Visual doesn't tell us which one it is tied to, but given that the 29F800 on 7100 DIMM works, it must be tied to Power. I wonder why? The ROM chips have a...

Pin 33 definitely appears to be tied to something in @mizerable 's photo. Must be power plane.

There were a number of signals listed in the ANS CPU pinout that weren't in the Apple CPU card, or the other way around or something like that. I had an engineer from NewerTech giving me a little help on the sly; I think he's safe if I mention that now... But in the end, IIRC, there were...

Those conversions really shouldn't work, unless the 7100 ROM DIMM is supplying 5V on pin 33 for each of the chips. Perhaps it is. Now I wish I hadn't put that 7100 ROM away. I don't want to dig it out again. At least I know where it is... These chips (AM29F800/HY29F800) can work in 8 bit...

Never mind. Almost made it to bed and then remembered that there's a thread somewhere where someone replaced the chips on a 7100 module to make an ANS ROM. Dug out an old 7100 ROM and checked pin 28 and it is NC. So, assuming that report was a good one, not having pin 28 connected should...

Found in my notes from about 20 years ago when I was pinning out various ROM modules by hand, that Pin 28 of the ANS ROM is tied to GND through a 10K resistor. I hope that isn't necessary for them to work because the modules I made don't do that... I think I see a way to add a bodge, if...

Let's let ClassicHasClass do his testing first, to determine whether I made any fundamental errors. I would hate to start assembling these for folks only to find that every single one has some fatal problem. I made four because that way, if they all fail, it's probably a procedure flaw. If...

Typically, the heat sink grease has turned to chalk with age and needs to be cleaned off and replaced. Machine is overheating causing random crashes. Probably runs longer from a cold start and then starts crashing more frequently after being on. When removing hte heat sink from the CPU be...

I'm not sure that page is correct. Years ago I crawled through the Apple Developer Notes for those machines in detail. I'm not going to redo that work, but my conclusion at the time was that the 7200's list of supported memory chips/DIMM configurations suggested that a 256 MB DIMM could be...

Apple's talk about megabits per chip is detailed talk about the exact way the machine addresses memory. Without understanding all about RAS and CAS and how memory is addressed, that's not going to mean much to you. I typed a very detailed explanation once. I have no idea where. Probably...

Four ANS Macintosh ROMs ready to test. Will get them to ClassicHasClass soon.

Thank you. That's what I needed to know. The need for swapping order/label is not an error, so much as an artifact of historical labeling. There's probably something that needs to be changed to make it more sensible, but I'm not sure what at this point. Ah, here's what happened. My...

Checking: You left the extracts in the order that kansas_deinterleave produced? In other words, U1 = U1, U2 =U2, U3=U3 and U4 = U4? I must swap U2 and U3 (artifact of labeling on circuit board) and I want to confirm that you did not pre-swap them. It seems unlikely, but a careful reading...