ITXPlus: A ITX Sized Macintosh Plus Logicboard Reproduction

5/22/2025 at 4:35:13 AM

One reason why the TFA might have chosen the Plus: the SE and SE/30 consolidate a lot of glue logic that are on PALs that can be cracked into not-so-easy to crack ASICs. The SE/30 has a notorious “GLUE” chip that has 80 pins, and most likely won’t be cloned anytime soon.

by nxobject

5/22/2025 at 6:25:08 AM

I wonder if it would be easier to design a new Mac model from scratch(ish) and put drivers in the ROM. AFAIK Basilisk II doesn't emulate a real Mac but the System doesn't notice because of ROM patches.

by wmf

5/21/2025 at 11:03:27 PM

Very cool. I think this is probably the way forward for various types of retrocomputing now that original chassises are disintegrating due to aging plastics and parts are becoming more scarce.

It’s a much higher bar to clear, but I’d love to see this treatment for some PPC 603/604, G3, and eventually G4 era Macs… I love the idea of building an ITX G4 cube.

by cosmic_cheese

5/21/2025 at 11:08:44 PM

As you get into more and more modern designs, there are more high speed signals and the motherboards get increasingly more complex.

Not that it can't be done, but the work to reproduce something made at the cutting edge in the 2000s feels like it'd be an order of magnitude harder than 70s/80s designs.

Though I'm always amazed what the retro communities will do to preserve the tech for future generations!

by geerlingguy

5/21/2025 at 11:35:58 PM

That’s alright though. SE/30 was Peak Macintosh anyway.

by whartung

5/22/2025 at 3:19:24 AM

The 9600/350 was a thing of beauty.

by sneak

5/22/2025 at 3:57:19 AM

Link: https://en.wikipedia.org/wiki/Power_Macintosh_9600

by runjake

5/22/2025 at 4:12:50 AM

My memory is that the Power Towers were incredibly hard to service. If correct, that's a shame, because the IIci I used at work was lovely to work with.

by mixmastamyk

5/22/2025 at 4:43:37 AM

I’ve read that the predecessor to the 9600, the 9500, wasn’t the easiest machine to work on. The 9600 had a more convenient pull-down case, which was continued in the designs of the beige G3 tower, the blue and white G3 tower, and the G4 towers.

by linguae

5/22/2025 at 9:42:43 AM

An unlike the 9500 you could even get at the RAM slots without breaking the damn plastic clips as use tear down the whole machine. Whoever combined the 9500 case and mainboard deserves as special place in engineering hell.

by crest

5/21/2025 at 11:51:25 PM

Heck, I'd be happy with a board that had the power/emulation of a 68040 so we can run MacOS 7.6 and some of old apps from back in the day.

by vondur

5/22/2025 at 10:31:56 AM

A small ARM board can do the job easily, but that won’t be very close to the actual experience. Playing with the C64 Maxi made me understand how important the physicality of the system is to the experience. It’s nice to have a physical 68000, but that level of fidelity is not really necessary for a user to understand what a Mac was about. A keyboard with a locking Caps Lock key is.

by rbanffy

5/22/2025 at 2:36:23 PM

A big problem with emulation that has yet to be overcome entirely is the added latency. Any of my newer machines can emulate a 68k Mac at full speed and I can hook up my Apple Extended Keyboard II to help replicate the physical portions of the experience, and yet using a real old Mac feels notably different simply because it doesn’t suffer from the latency papercuts brought by USB and modern operating system.

That’s one of the things that jumps out at me when I pull out my old PowerBook G3 and boot it into OS 9 on occasion: it feels incredibly responsive relative to modern counterparts, especially with an SSD removing the wait times that normally came with a spinning disk, despite it being only a tiny fraction as powerful.

by cosmic_cheese

5/22/2025 at 3:09:37 PM

You can mitigate the latencies by making the CPU faster, pushing more work to the GPU, using an analog VGA output, or trimming down the OS so that as little as possible preempts the emulator.

by rbanffy

5/22/2025 at 3:48:24 AM

68040 CPUs are easy to find. Motorola was shipping them in ASTRO mobile radio infrastructure equipment well into the 2000s, and a lot of that gear is getting scrapped now.

by bigfatkitten

5/22/2025 at 12:54:07 AM

Considering that we've moved from wire wrapping to being able to design and order multi-layer circuit boards, and we've gone from 74 series and basic PALs to CPLDs and FPGAs that regular people can program, I don't think what tinkerers can do will hit any barriers any time soon.

The ability to recreate classic computing is wonderful, both in preservation of history and in making things available to people who hadn't even been born when these machines were new :)

by johnklos

5/22/2025 at 5:34:40 AM

Though, the late 90s feels achievable.

The Front Side Bus of the Pentium III maxed out at 133 MHz, single transfer (and was often configured at 100 MHz for lower spec CPUs), and the AMD K6 was even slower. I don't have much PCB design experience, but my understanding is that 133MHz is quite achievable for hobbyists these days.

Things very quickly go off the rails after that.

by phire

5/22/2025 at 2:06:31 AM

Fortunately for later CPUs, especially on the PC/x86 they are usually based on reference designs, and the amount of documentation available in electronic form much greater. Late 2000s is when they started closing up and being more secretive, and I'd consider that a greater concern.

by userbinator

5/22/2025 at 10:21:39 AM

> now that original chassises are disintegrating due to aging plastics and parts are becoming more scarce.

We need to start making detailed 3D scans of parts. The original parts will degrade, but we can make accurate reproductions of those parts. It would be great if museums took part of that effort, even if for no other reason than having the historically relevant items all in one place.

by rbanffy

5/22/2025 at 11:28:11 AM

I love that idea.

The ergonomics of that first Mac design remain my favorite of any computer. Loved the keyboard, the screen even though it was black and white, and even the handle. It made carrying the computer remarkably easy. Would be awesome if I could experience it again without worrying about leaky batteries or exploded capacitors.

by tomcam

5/22/2025 at 3:06:29 PM

Remember the original Mac didn’t even have cursor keys.

by rbanffy

5/22/2025 at 8:25:10 PM

I’d forgotten! Fascinating in retrospect

by tomcam

5/22/2025 at 3:10:47 PM

Well these guys are doing some earlier Apple parts:https://maceffects.com/collections/all

Talked to these guys at VCF East this year. They are total rockstars but man its expensive to do this stuff. We are talking well into 6 figures for just the molds and testing. Probably not even started production at that point. And doing it outside of China? Good luck.

by nebula8804

5/22/2025 at 12:04:35 PM

none of those PPC CPUs are still in production, to say nothing of the many other undocumented custom chips used in those Macs. the 68000 is still available new.

by Palomides

5/22/2025 at 9:22:17 PM

Higher speed grades of the 68SEC000 are happy operating over 50MHz, if you want the world's quickest Mac Plus.

by bigfatkitten

5/22/2025 at 11:23:21 PM

Literally anything would be an improvement. That machine drags. I'm sure it was quite something in its day, but I got mine in 2011, and it frustrated me so much I went out and got an SE/30!

by theodric

5/22/2025 at 12:47:45 AM

I imagine FPGAs would be a great way forward for retro computing, just like it is for retro gaming.

by redundantly

5/22/2025 at 1:02:41 AM

FPGAs hold a lot of promise, but as I understand have limits on performance and can be on the power hungry side which can preclude some later CPUs and make portable form factors impractical.

by cosmic_cheese

5/22/2025 at 2:35:08 AM

https://mister-devel.github.io/MkDocs_MiSTer/

by wmf

5/22/2025 at 1:01:11 AM

Retrocomputing and retrogaming are going to get a boost from a hybrid approach: using uC boards like the Raspberry Pi Pico to emulate each individual component. You get timing accuracy that's close to FPGA, but at $5 a pop, the components are cheaper than an FPGA board would cost.

The Connomore 64 is an example of a complete system built this way. I'm sure Mac, Amiga, and Atari ST clones will be incoming. https://github.com/c1570/Connomore64

by bitwize

5/22/2025 at 12:57:57 AM

Nice! Makes me want to buy a Mac again.

by bitwize