Mac SE/30 logicboard recreation | Hacker News Reader

Mac SE/30 logicboard recreation

68kmla.org

207 pointszdw55 comments

The person working on that project does incredible work. I have one of his upgrades that added a 40 Mhz 68040, 128k cache, and Ethernet to my old SE/30, and it's been fantastic. I run System 7.1 on it to play around with HyperCard, Word 5, Excel 4, and a couple other old programs.

It's fun to make things in HyperCard as a great interactive and immediate feedback teaching tool for introducing my kids to programming. More than that though it's nice to sit down and draw inspiration from an era and implementation that went out of its way to take a handful of very well researched UI & UX metaphors and deploy them consistently and thoroughly. When I fire the thing up and poke around it feels like having the Software Engineer & Product Designer version of a serene Japanese garden. The transition from a little 9" B&W screen to my dual 27" LCD workstation is always jarring, and I always feel like the clarity of my thoughts and focus suffer immediately.

Does Bolle sell those upgrades? Got a URL?

He makes small batches of them at a time. Some of them depend on old ASICs from companies like DayStar digital, so I think supply is sometimes constrained by ability to acquire those old chips.

The best way I know of to get ahold of him is to become a member of the linked forum.

What I'm hoping for, and this extends to all the reproduction-PCB projects (aside from the Mac ones, I've seen a replacement Atari 800XL and some Amiga designs) is that we can come up with a way to reproduce the ASICs rather than scavenging them from dead units.

For some machines, there may be an ample supply to scavenge (old Macs being famous for barfing their batteries in a way that destroys the PCB but leaves the chips intact), but some other designs have far more limited supplies of spares. Plus there's the attrition risk-- something is gonna get damaged while parting out some percentage of the time.

The introduction of replacement ASICs would allow us to grow the total population of a rare platform. I could imagine offering a turnkey kit-- a PCB plus every part necessary to populate it and have a working vintage Mac/Amiga/Atari/etc, with fresh capacitors and enthusiast quality sockets and PCB materials. They were able to offer such a kit for the IBM PC, but that was famous for not using custom components.

Really, the best way to solve this is likely with FPGAs, not ASICs. If you're not using an original chip, does it really matter if it's an FPGA or not? Already, most of these reproduction PCB projects, including this one, end up using PLDs to replace hard-to-find specialied ICs (and even those PLDs are at risk of EOL). So it's not like they're using 100% original chips, anyway.

I understand the urge, but unless the cost of ASIC manufacturing drops dramatically, I don't see this as being practical for small runs like hobby reproduction boards.

Edit: I forgot to add: this is impressive work, nonetheless!

Further in the article, there’s a discussion of replacing custom PAL logic with modern Atmel chips.

I mentioned that ("including this one"). Problem is, they're Atmel chips that are still in production, but I wouldn't call them "modern". Most competing PLDs are now out of production, and it wouldn't surprise me to see the atmel f16v8 series follow. More and more people just use cheap CPLDs or FPGAs (which unfortunately aren't available in DIP packages and so not pin compatible with the old custom ICs used in the 80s).

its pretty easy to make SMT to DIP adapter PCBs, doesn't work with large chips, but a small FPGA is all you need for such old ASICs anyways.

http://www.the8bitguy.com/wp-content/uploads/2018/05/SwinSID...

I suppose it depends on how you're using FPGAs. It seems like a lot of the FPGA products-- things like MISTer-- are system-level emulators, which rarely provide full legacy I/O breakout. You can emulate a complete 68k Mac on a FPGA, but where do you attach that weird NuBus card?

Now, replacing individual chips with FPGAs/PLDs is likely to retain that, although I could imagine it's a lot less forgiving of an emulation, when it has to match the analog-domain properties of the original chip somewhat.

> You can emulate a complete 68k Mac on a FPGA, but where do you attach that weird NuBus card?

I just looked, and NuBus has 96 pins with clock rate of like 20 MHz. There are FPGAs with > 500 GPIO that can easily handle that clock rate, and ones with over >200 GPIO that are fairly affordable. Now, I mess around with FPGAs, but I'm not an electrical engineer, and there may be other issues. But it seems doable.

Any electrical engineer and/or hardcore FPGA hacker want to chime in?

It also looks like at least 30-40 of the pins on NuBus are either grounds or power supplies, so it's not even as bad it seems.

Yeah, those wide parallel connections were pretty much universally power/ground heavy for signal integrity reasons.

If you read the comments on the story, the author did appear to have reverse engineered several of the Apple branded PAL chips on the board. So he was able to program new ATMEL PAL16R8Bs as replacements.

> They were able to offer such a kit for the IBM PC, but that was famous for not using custom components.

Are 8086 CPUs still manufactured?

8088

Some people prefer to tinker with hardware, and find designing a new PCB easier than attempting to implement an entire machine in an FPGA or ASIC. Some of these older systems, like the Mac SE/30, the Amiga, Ataris and C64 are simple enough that you can successfully debug and fix many issues with little to no background in electronics, and that provides a great way for people to learn.

Most enthusiasts will most likely use both emulator and real hardware. There is some sense of enjoying and sense of nostalgia coming from using real hardware.

What I would like to see is more work trying to recreate the chips required to repair or even recreate these old machines.

If we just want to be able to access software and data from old systems, FPGA or emulators are fine, but if we also want to retain the experience, I think real hardware provides an added layer.

Its the logical next step. We may have to wait a while.

Maybe there will be some standard small FPGA that can sit in various packages.

At that point, wouldn't it make more sense to just emulate the whole thing in the FPGA, instead of individual chips?

Very nice even with the SCSI mistake. Plenty of production systems shipped with more bodge wires than that.

Nice project. Tip: for high quality CRT photos make shutter time is equal to a multiple of the refresh period. 1/60th, 1/30th, 1/20th and so on.

The vsync of the se/30 is 59hz so good luck with that

Stop down and take a long exposure. You just want to avoid the focal plane shutter or digital rolling shutter, and capture one beam paint, or lots of beam paints to even out the intensity.

Preserving or recreating the logic boards is important for historical recreation of antique machines — as the originals get destroyed, there’s less opportunity for new research. Having recreations like this lets more people play with these historical machines.

Another cool part is that those old boards could get extended so that we can more easily sniff the buses or pause and visualize main memory, etc. So that we may better lift these artifacts into a purely symbolic space.

Looks like decent progress being made on cooking up modern replacements for some of the custom chips, too. The prospect of being able to make fully-populated logic boards from off the shelf parts is exciting!

Wow! Impressed that he was able to get away with 4 layers. I wonder why apple needed 6 layers? More grounding?

My 100% guess would be 30 years of improvements in automatic PCB layout software and CPU power to run it (it wouldn’t surprise me if the original was partly/largely/fully laid out by hand, but that’s a guess, too. It wouldn’t surprise me because I know very little about this)

Auto layout is still pretty terrible and used sparingly.

I would guess it’s more 30 years improvement in CAD - it’s easier to keep fiddling with the layout until you make it work than it used to be.

Don't forget the improvement in the design rules in the fabs as well -- the minimum distance between traces can be dramatically reduced safely compared to the past, as (presumably) can be the digital resolution of the gerbers (i.e. curved traces, however horrible to the eyes of some EEs, are allowed!). Also, yuckies such as via-under-pad and the like are all now commonly accepted (but I didn't see any on his layout).

Maybe my dream of a Mac SE/40 can finally be realized, all one board. No add on accelerator.

Well old Macs with a PDS slot, the sky is the limit since it is bare CPU bus address lines configured as an expansion slot!

If this is ever for sale, I'm buying it.

It makes me wish I had kept my SE/30.

What is the likelihood of Apple dropping an army of lawyers on this? These PCBs are probably copyrighted. My understanding is that schematics are fair game as long as they don't look the same in terms of component placement (but connections can be identical), but a PCB can be protected the same way as a painting?

Accord8mg to the site this board is four layers. The original board was six. Presumably it’s different.

I vaguely had the impression that the original boards tended to fail over the years due to the capacitors.

I'm wondering, if this replacement board doesn't have them, how was that done?

I suspect the solution is that 1) you're going to assemble the new board with a fresh set of capacitors, resetting any wear/degradation clock, and 2) modern capacitors are likely improved from the early-generation surface-mount ones in many old Macs.

I'm very hardware illiterate - I meant that I didn't see any of the big cylindrical ones and wondered if there is some story behind why they're not needed.

Like this: http://pc-restorer.com/wp-content/uploads/2014/02/SE30-bad-c...

The caps in your linked photo are 47μF. The orange squares in the jumper wire photo are 47μF tantalum capacitors, that won't leak. You don't need those big cylindrical ones for such low capacitances anymore.

Apple hasn't nuked stuff like the Mac ROM-inator that is obviously infringing and being sold for money so presumably they don't care.

You cannot copyright circuit designs in the US. Those fall under a separate sui generis rights regime for "maskwork" that has a far shorter lifespan than creative works do - about 10 years. (God, I wish software had followed this path, instead of the bodge job that "just copyright software" got us.) Patents might be an issue, but those expire after 20 years in the US. It's almost certain that no unexpired patents or mask work rights cover these old PCB or chip designs.

In order to actually make a copyright claim on a reproduction PCB, you have to argue that the PCB reproduces a copyrighted work, such as the contents of a Mask ROM. However, if you can avoid needing to reproduce those ROMs, then you're free and clear of copyright issues. For example, you could just provide a ROM chip socket matching the original board, or ship a flash chip with a workalike ROM (if that is an option by the time SCOTUS decides Oracle v. Google).

The only avenues left would be trademark or trade secret protection. Apple loves sticking their logo all over replacement iPhone parts, and for whatever reason Chinese clone part manufacturers continue doing so. The Shenzhen markets like that, even though foreign part importers beg them to stop doing that. Presumably, however, anyone cloning an SE/30 board in the US would know to not stick Apple logos on the thing. Trade secret protection claims would also be rather spurious as the machine in question is very public, you didn't sign an agreement to keep the machine's design confidential, and reverse engineering is legally protected within the guidelines I stated above.

Thank you

I'm impressed you can still get all of the components to populate the board. I'd expect a bunch of the support components to be basically unavailable by this point.

It's uncanny seeing a CPU that looks so serious and complicated but yet has almost no decoupling capacitors while my microcontroller has let me check 32.

decoupling caps are pretty seriously overrated, there are cheap grey-market re-manufactured Chinese Intel core series motherboards that have essentially zero passives (except on stuff like VRMs)

They still work fine.

https://www.aliexpress.com/item/32941784993.html

Who needs a re-creation? I just pull my SE/30 off the shelf. Still boots! :)

better check the battery...

Inspect that critter carefully and regularly. Leaking batteries are common and will destroy the machine (e.g. corroded PCB traces and IC pins). It is also from an era which used capacitors were leaky. I don't know if the latter will destroy the computer, but careful repairs are required to keep it running.

Where does somebody get the ROMs for one of these?

You can get an improved ROM from https://www.bigmessowires.com/mac-rom-inator-ii/

It's nice of Apple to license/allow/overlook this, whatever the case is.

Adobe is going after 27 year old historic artifacts. https://news.ycombinator.com/item?id=26474032

Excellent!

I appreciate this for academic purposes but in reality, unless you have a really unique / odd peripheral that only works with the antique machine's interfaces, it's much much easier to emulate in software.

We don't do this because it is easy, we do this because it is hard.

You might be surprised by how few good classic Mac emulators are available. There's basically only vMac and Basilisk II, and neither of them targets the SE/30.

Reply on news.ycombinator.com