Early in 2019, it  became apparent that the retro-industrial complex had reached new highs of innovation and productivity. It was now possible to create entirely new Commdore 64s from scratch, thanks to the combined efforts of a series of disparate projects. It seems as if the best selling computer of all time may indeed live forever.

Naturally, this raises questions as to the C64’s proud successor, the Amiga. Due to a variety of reasons, it’s less likely we’ll see scratch-build Amiga 500s popping out of the woodwork anytime soon. Let’s look at what it would take, and maybe, just maybe, in a few years you’ll be firing up Lotus II (or, ideally, Jaguar XJ220: The Game) on your brand new rig running Workbench 1.3.

The Case For A Case

The Amiga 500+ case project from Indiegogo promises backers a fresh new enclosure for their classic Amiga, Raspberry Pi, or Vampire board.

The first part you’ll need for a replica build is a case to put everything inside. This is at once the easiest or most difficult part to source, depending on your taste for authenticity. Unlike the C64, one can’t simply jump online and order a near-factory reproduction off the shelf. A project to produce lightly upgraded replica cases hit Indiegogo back in 2018, however, as yet, parts have not shipped to backers.

This leaves the budding builder to find a solution of their own. For the individual, creating injection molds and doing a production run is likely out of the question, but if you’ve got a spare million laying around, have at it. 3D printing is an option, of course. This would require the construction of an accurate 3D model, and would probably need to be printed in somewhere between many parts, depending on the size of your 3D printer. Significant work would be required in finishing too, to get a good-looking final result. Still, this is where we’d place our bets.

Another option could perhaps be doing a very large silicone cast to produce a copy of an original case. To achieve good results would require advanced skill, lots of experience, and high-end tooling. We personally haven’t seen this technique used on parts of such size, particularly with large flat surfaces which can be difficult to replicate. But if you felt like doing a run of a few cases at your home workshop, and have a year or two to spare, it could be a fun project.

The Motherboard

Next, you’ll need a motherboard. In this case, things are looking up – it’s possible to source a new A500+ PCB off Tindie, thanks to the hard work of [Bob’s Bits]. Called the A500++, it packs a few minor updates that improve the design for modern builds. This includes nice touches like having provision for a regular round DIN power connector instead of the original square part, and extra breakouts for pins often used with modern expansions. Others have done similar work in the past, albeit in limited private runs. There’s also a raw A500 board on PCBWay that is untested and seemingly missing some important routing, if you’d like to give it a shot.

The A500++ board from [Bob’s Bits] comes in black or purple, with silkscreen graphics that are a faithful update on the original.

Of course, the motherboard is just the starting point. You’ll need all the bits that go on it, too. A BOM is available, thankfully, which makes sourcing the commodity components easy. Sourcing a CPU isn’t too hard either, as the Motorola 68000 was a hugely popular part with many applications. ROMs are easily found as well, as swapping out different Kickstart versions is a popular compatibility mod to old machines.

Unfortunately, things get harder from there – and it’s all due to the magic that makes the Amiga great. Both the Commodore 64 and the Amiga relied heavily on custom silicon to give them a performance edge over their rivals in the marketplace. The former had its famous SID audio chip, along with a bunch of glue logic for peripherals and of course the VIC-II chip which handled video output. The Amiga, developed entirely independently by a startup bought out by Commodore, had Agnus, Paula and Denise, along with a smattering of others. These were broadly in charge of DMA, audio and video respectively, though in reality other functions were handled by the chips as well.

Being purpose-designed silicon ICs with a single application, these parts went out of production along with the computer itself. Some chips, like the VIDIOT IC, have been replicated by the community, and there are rumblings that Gary may have been replicated on a CPLD, too.  For the big stars of the machine – Agnus, Paula, and Denise – the only viable source is harvesting chips from old machines or dwindling supplies of “new old stock”. This remains a major stumbling block for those attempting a new build.

This blurry image from 2011 shows [Jeri Ellsworth]’s prototype Amiga on a chip. It serves as a proof of concept that the OCS (and ideally, later chipsets) can be implemented in an FPGA.

FPGAs hold promise as a solution to this problem. However, projects thus far have focused on reimplementing the entire Amiga 500 in a single FPGA, rather than discrete chips to plug into an original motherboard. The Minimig has been a long-term player in this space, and the upcoming Vampire V4 standalone will be a similar machine.

These projects bring new power and capability to the Amiga platform, but tend to stray from the feel of the original machine due to their major differences in design. Nevertheless, work by [Jeri Ellsworth] as far back as 2004 suggests that implementing the OCS chipset in FPGA form is achievable. Her prototype hooked a single FPGA into a stock A500 motherboard, replacing all the custom chips except for Paula’s disk interface and the original 68000 CPU. The work was intended to lead to a follow up of the C64 DTV, but was abandoned to create a Williams arcade emulator instead. Snatching failure from the jaws of defeat – how very fitting for the Amiga story!

Peripherals

If you’ve got a new Amiga, you’ll need some peripherals, too. Mice are easy, with new, albeit anachronistic devices readily available. USB adpaters exist too if you simply can’t do without your 5000DPI Razer full of flashing LEDs.

I’ll have one of these with an i7 and 32GB of RAM, thanks. Oh, and make mine a 500, natch.

Keyboards are a different story, and things get a little hazy. [Amiga On The Lake] has pre-orders open for a new Cherry MX-based keyboard that looks great, though we’re unsure how close the project is to shipment. It reportedly comes complete with keycaps and a USB interface for using it with alternative hardware, too. [A1200.net] have also shown off a prototype device, though again, it does not yet appear to be publically available. Their keycap color configuration tool for the A1200 is pretty boss, but actual product seems hard to come by.

As far as storage goes, original floppy drives are rare and getting rarer. Your best bet is instead to use something like a GoTek emulator instead. Alternatively, if you’ve got a SCSI interface lying around, the SCSI2SD is a great option, but this relies on more old hardware. Things will have to go pretty far before people start recreating the A590, we imagine.

In Summary

Overall, the idea of building a brand new Amiga 500 is a reach for even the most dedicated enthusiast. Before it’s easily doable for the average fan armed with a credit card, as it is with the C-64, there remains much work to be done. A reliable source of cases is needed, and significant holes in the supply of important parts need to be filled in.

There are a multitude of reasons why this is the case. The Amiga 500 never sold in the same numbers as the Commodore 64. The Amiga ecosystem is far more split, with the 500, 600, 1200, and even 2000/3000/4000 each having their own distinct fanbases. Thus, there are many smaller groups working on different projects, versus the Commodore 64, which has its whole community focusing its effort on recreating just one machine.

Achieving the feat is not impossible by any means. However, it will likely require the dedicated effort of a skilled few, along with a great deal of money to accomplish. It may be such that the Amiga fanbase is not quite strong enough to support the same level of aftermarket as the C64, but we remain hopeful. May those gorgeous 16-bit-ish machines once again rule the world!



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