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Thanks, I think it is, indeed cool. One of the coolest aspects is that it's small enough to fit in half an RP2040's 16kB cache and because of the way the cache is partitioned, a Mac ROM and disk will occupy the other half most of the time. Correction though, there's not enough RAM for a Mac...

I think both I and @joevt still thought this was about emulating a Game Boy (not GBA, nor Color Game Boy) on a 68000 Mac, as per the beginning of the thread. If, e.g. you're thinking about emulating a 68000 on ARM you might want to check out the posts and comments on MØBius (unless you've...

Good point. Isn't the original Game Boy based on a Z80 architecture? https://realboyemulator.wordpress.com/wp-content/uploads/2013/01/gbcpuman.pdf Normally a Z80 won't have much of a preference for even vs odd addresses, and application data structures won't be aligned on even boundaries...

So, if d0=the 16-bit address and a0=membase it's: BTST #0,d0 ;8c? bne.s Unaligned ;10c/4c? move.w 0(a0,d0.w),d1 ;value 16c? bra.s LoadDone ;10c Unaligned: move.b 0(a0,d0.w),d1 ;hi byte 16c. lsl.w #8,d1 ;8*2+6=22c. move.b 1(a0,d0.w),d1 ;lo byte 16c LoadDone: ;Total =...

Yes, it would be very cool! An Arduino wouldn't be correct gear, but I don't know any period light-show MIDI interfaces and this would work. You could take an Arduino version and then port it to a mid-80s SBC or buy or build one from eBay to do the same thing. e.g...

I'd go for a MIDIMAN Mac Midi interface. For software, early Cubase and Cubase lite: https://macintoshgarden.org/apps/cubase-lite-10-68k This works OK on a Mac Plus, so it'll be very capable on a 68030. Which 68030 are you using? I guess you're using a Compact Mac, so it's either an SE/30...

An Arduino Mega256 would have enough I/O pins to test a SIMM. The most challenging bit will be to test memory at the full speed of the memory. Basic functionality would be fine though.

I've had to take apart my Mac Plus and SE from time to time. I'm not particularly clumsy as such (I've recently replaced an iPhone SE 2020 screen and battery, then an iPhone XR screen), but I lack some degree of multiple spatial awareness so I could quite easily touch a CRT while removing some...

Thanks for the earlier reply. Great to get some feedback. The MØBius core emulator is written. It currently compiles, but doesn't properly assemble into an object file using the gcc-arm-none-eabi assembler (i.e. gcc-arm-none-eabi -c -o MOBius.o MOBius.s ). Getting that done would be the next...

Consumer Mac plastics from that era, including the P5200 and P6200, all the way, I think up to the P5400s get brittle and break. But also, they're more likely to break in more demanding environments, e.g. many locations in the US (AFAIK, but I could be wrong). By contrast, the plastics on my LC...

Thanks for the message, not ignoring you, will reply before too long.

https://infinitemac.org/1984/System%201.0

I didn't feel you were. Sure!

64kROM is good enough. I know that MACE lists which managers it's implemented. Is there a corresponding list for AMS? If it did exist, is it on a Google docs spreadsheet and if so, could it be of the form: ManagerRoutineA-line Usability% Complete% Tested QuickDrawSetRectA8A7A100100...

AMS is a really intriguing project. Does it provide all the original Mac or Mac Plus ROM calls yet? (I'm aware it provides a lot of stuff for colour Macs, I think. Aaah, that's a related project.)

Good point. The ZX81 also didn't generate correct HSyncs and so pretty much every TV in the past 30 years won't work properly. It ought to generate, I think, 0V for about 4.5µs then 0.3V (black) for 4.5µs; which the TV uses for calibration. The ZX81 goes straight from 0V to 1.0V for the white...

Amongst my numerous ZX81s, I have a very early one, with the ROM chip fix. It's a very different one to the later ZX81s. It's worth checking it out. I thought I'd written a blog post about it, but I can't find it. The upshot is this though. As you know (as revealed by Dr Ian Logan), the original...