this seems to be a ROM for a later Unitron clone, the "Unitron 1024" which work was started on after the US govt threatened and forced the shutdown of the "Mac 512" project. supposedly the Unitron 1024 wasn't going to look like a macintosh, in an attempt to appease the government, but it also got shut down regardless

the Mac 512 was shut down not because the case looked like a mac, not because the analog board was a carbon copy, but because the unit that Apple somehow managed to investigate for themselves during development contained a copied Mac Plus ROM. however, Unitron's argument was that that was only being used for development purposes and the retail version would contain a reverse engineered rom. at the time, there was no law against that in brazil

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this is a screenshot that i believe to be from the Mac 512 retail ROM (it says "Insert the initialization disk" in Portuguese). in trying to locate this ROM (the only known dumped Mac 512 ROM is actually the Mac Plus copy) i accidentally found the Unitron 1024's instead.

i can only find the "Unitron 1024" mentioned online in two places:

one is in a posthumous legal study of the Mac 512 case in which it's mentioned as an addendum

the other is a supposed MAME driver for which any rom i've found are just... mac plus roms.

development documents. this mentions the rom is for both models ("Mac512/Unitron 1024") but i don't think the sources in them are complete

the source i found has several floppy images, but also some folders that seem to be from different floppy images destructively extracted into a FAT type system so some of it might be lost

i actually found two roms, one larger than the other, but so far i can only get the second one to do this

i wanted to investigate these more before uploading them but i lost interest. here they are

it looks like they're (at least partially) compiled from C(?), not sure how complete they are, not sure how much of them are still just copied from apple roms. both have the same build date, smaller one seems to boot and the larger one just sadmacs. functionally the only difference i could see are graphics. the sources are as far as we know completely lost.

netizen.club/~maple/files/unit

the only other known dump of a Unitron Mac 512 ROM is the earliest one, which is identical to the Mac Plus ROM, which caused the Apple lawsuit which shut down the project. had Unitron not rushed to market before they could've made a clean room clone of the ROM (which the eventual Unitron 1024 tried to, too little too late), the Mac 512 project might have passed certification (necessary to be sold) and survived.

some misconceptions: Unitron did not work on multiple mac clones, it only changed name:

"Mac 512" is the initial project, which was simply a straight up copy of the original Macintosh with 512K RAM, eventually became closer to a Mac Plus clone

"Turbo Mac" is the same identical machine with improved PAL timings for RAM access which sped it up

"Unitron 1024" is the same hardware with 1MB RAM, in a futile attempt to make it more legally distinct after the lawsuit

none of it fully came to market

@mavica_again This is awesome, thank you so much for finding these, investigating them and sharing!! :D

@mavica_again Thanks so much for sharing these-- I did a comparison of the earlier Unitron ROM a few years ago: twitter.com/ablitter/status/13

Looking forward to diving deep into these!

(BTW, RomUnit is 404ing 😞 )

@blitter sorry about that, my nginx path solving was unhappy with files without extension -- should work now

@mavica_again I see a bunch of stuff pull up on DuckDuckGo and google?

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