Recent content by joevt

In that case, I wonder if it means anything that the Beige G3 doesn't have a U44? The schematic has 23 components with a U prefix numbered 1 to 47. Why does it skip some numbers?

Reconnaissance depends on the diagnostics mode in the ROM. The Mac has to work well enough to run that code. If the 3rd party ROM doesn't bypass the diagnostics, then it should work. But don't some of these ROMs skip the diagnostics (RAM tests, etc.) to boot faster?

Thanks for checking. That exactly matches the info for the 2.26NT ROM which we already have. 077d.28f2.1 962f6c13 045a4042.04a81401.033345a1.03ffe57d 02cdecec.031ec3af.0213d883.02837b28.02a7be75.03853500.023892c2.02a52e8a:c60da96de537f08a 23a7bbda5681be978972517d4758bbdd "1.1.20.1"...

Also this thread is interesting for really old Mac system software: https://68kmla.org/bb/threads/writing-an-application-that-runs-in-mac-os-system-1-using-codewarrior-gold-11.47511/

CodeWarrior Pro 6 was the last version of CodeWarrior to support 68K targets. CodeWarrior Pro 4 was the last to run on 68K hardware? CodeWarrior 11 is also an important version. Some other notes: https://68kmla.org/bb/threads/metrowerks-codewarrior-best-version-and-updates.42338/ I don't think...

Try the "Connecting to Open Firmware" section here: https://forums.macrumors.com/threads/question-how-powerful-of-a-graphics-card-will-work-in-a-beige-power-macintosh-g3.2303689/#-connecting-to-open-firmware Connect to modem port. In Open Firmware use this command to redirect input/output to...

When you are able to boot into Open Firmware, you can use the script at https://tinkerdifferent.com/threads/apple-network-server-macos-based-roms-found.4756/post-41390 to see all the checksums.

Coincidentally, the Power Mac 4400 schematics do have a U44 connected to MFM. The 4400 uses OHare as the mac-io controller. I suppose the U44 MFM controller was moved into Heathrow and Paddington and those newer chips added the MFM feature control bits?

U44 is not mentioned in the Beige G3 schematics. https://www.macdat.net/repair/apple_schematics.html The schematics do have the GCR and MFM slots. The MFM slot connects mostly directly to Heathrow so maybe U44 doesn't have anything to do with it? There's a couple resisters R340 and R341 marked...

Might need to set some feature control bits. https://68kmla.org/bb/threads/beige-g3-ram-and-psu-questions.52027/post-587215

Your graph doesn't show the voltage reaching zero. How high of a current (lowering of resistance) did you try for each power supply? Would too high a current have voltage reach zero or would it damage the power supply? Is there a way to make the 2.0A power supplies have a similar curve as the...

Add Apple II graphics using the Apple I expansion slot?

So Linux already has a FireWire Target Disk Mode capability. Open Firmware appears to have code to scan a range of LUNs, but for some reason the range is set to [0]. Maybe Apple had a good reason, like it wasn't fully implemented (LUN in a device path doesn't work?), or multiple LUNs might...

Looks good. I think it can be improved by changing the alignment of the pattern so that each white key is drawn with the same alignment relative to the position of the key. With the current alignment (relative to the window position), you see that the appearance of hilited white keys repeats...

Yes. That's the only one with 1 MiB files. Any reason to not connect them? Code for flashing various chips exists in New World Mac firmware updaters (Open Firmware code), and in open source utilities such as flashrom. I have a fork of flashrom for Mac OS X. I'll read those later. I was...