Extreme Refurbishing: Amiga Edition

The last Amiga personal computer rolled off the assembly line in 1996, well over 20 years ago. Of course, they had their real heyday in the late 80s, so obviously if you have any around now they’ll be in need of a little bit of attention. [Drygol] recently received what looks like a pallet of old Amiga parts and set about building this special one: The Vampiric Amiga A500.

The foundation of this project was a plain A500 with quite a bit of damage. Corrosion and rust abounded inside the case, as well as at least one animal. To start the refurbishment, the first step was to remove the rust from the case and shields by an electrochemical method. From there, he turned his attention to the motherboard and removed all of the chips and started cleaning. Some of the connectors had to be desoldered and bathed in phosphoric acid to remove rust and corrosion, and once everything was put back together it looks almost brand new.

Of course, some other repairs had to be made to the keyboard and [Drygol] put a unique paint job on the exterior of this build (and gave it a name to match), but it’s a perfect working Amiga with original hardware, ready to go for any retrocomputing enthusiast. He’s no stranger around here, either; he did another extreme restoration of an Atari 800 XL about a year ago.

A New Motherboard For Amiga, The Platform That Refuses To Die

If you go out and buy a computer right now, how many choices do you really have? Generally speaking, there’s PC or Mac. If we were being generous you could consider Chromebook and perhaps even mobile, but let’s be honest, computing is a two-party system with the ability to dump the OS and run Linux as the obvious third-party disruptor. It wasn’t always like this.

In the early years of personal computing there were a slew of serious contenders. A PC, a Mac, an Atari ST, an Amiga, and several more that all demanded serious consideration on the general purpose desktop computer market. Of all these platforms, the Amiga somehow stubbornly refuses to die. The Amiga 1200+ from [Jeroen Vandezande] is the latest in a long procession of post-Commodore Amigas, and as its name suggests it provides an upgrade for the popular early-1990s all-in-one Amiga model.

It takes the form of a well-executed open-source PCB that’s a drop-in replacement for the original A1200 motherboard. CPU, RAM, and video are broken out onto daughterboards, with PCMCIA replaced by an SD card slot. The catch: it does require all the custom Amiga chips from a donor board.

The original Amiga 1200 was a significant upgrade to the architecture of the 1980s originals, and this certainly provides a much-needed enhancement to its underwhelming 68EC020 processor. It’s fair to say that this is the Amiga upgrade we’d all have loved to see in about 1996 rather than waiting until 2019. It’s still a delight for a retrogaming enthusiast; many of those who keep it alive remember the Amiga was the best multimedia platform that could be had for a few glorious years.

We’ve brought you a host of Amiga projects over the years, including the resurrection of an A500 and of course another A1200 PCB.

Thanks to [Eric Hill] for the tip.

Creating A Contest-Winning Amiga Demo Soundtrack

The Amiga platform took the world by storm in the 1980s. Developed by a crack team and brought to market by Commodore, the OCS chipset brought high-quality graphics and sound into the home computer market in a way never seen before. These capabilities cemented the Amiga’s place in the demoscene, and it maintains an active development community to this day. [Hoffman] is one such member of that community, and has shared some of the hacks that go into pulling off a banging soundtrack in a cutting-edge A500 demo.

The Amiga has 512 KB of so-called chip RAM, accessible by the custom chips and CPU for all tasks. There’s also commonly an additional 512 KB in a trapdoor under the machine, though it is limited in the ways it can be used. With these limits in place, [Hoffman] was overjoyed when the rest of the team allocated him a full 200 KB of memory for the soundtrack. In order to make the most of this precious resource, hacking ensued.

[Hoffman] does a great job of explaining all the tricks involved in creating a compelling 5 minute soundtrack in just 200 KB of RAM. There’s discussion of compression, sample sizes, and the vagaries of the ProTracker format. Smart hacks such as prioritized sample loading and pre-rendering drum loops also help to get the project over the line.

It’s a great write-up, which clearly explains the strategies used to help build a world-class demo soundtrack. [Hoffman] promises that the tricks used by the rest of the crew are equally as impressive, which we’re sure helped Eon to win the Amiga Demo Compo at Revision 2019. We’ve featured Revision winners here before, too. Demo video after the break.

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Resurrecting An Amiga 500+

Recently, I was lucky enough to receive a big haul of retro computer gear from a friend who was emptying out his garage. Even better, the haul was almost entirely old Amiga gear — my favorite computing platform of all time. Upon returning home, I gleefully sorted through the boxes, powering things up one by one. Amazingly, everything worked… except for one lonely Amiga 500+. I was greeted by a dull grey screen. This wouldn’t do, so naturally, I got to work.

It seemed like a shame to be opening the machine, as after almost 30 years of life, this one still had its warranty seal intact. Regardless, nothing ventured, nothing gained – the Torx bits were at hand and the screws were coming out.

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Put An ItsyBitsy Zork In Your Pocket

Before computer games had all these fancy graphics, text based games were a very popular genre. Rather than move a character on the screen, you’d type out commands for your player in sentence form which the game would interpret; decades before the “cloud” language processing technology that the likes of Amazon and Google currently use to power their virtual assistants. In some ways the genre was ahead of its time, but it didn’t survive the graphical revolution for home computers. Of course, these games still have some diehard fans out there.

[Dan The Geek] is one such fan. He loves text based adventure games like Zork so much that he wanted to create his own implementation of the core technology that made these games possible all those years ago. But he didn’t want to just do it on this desktop computer, there’s already projects that let you run these classic games on modern hardware. He wanted to see if he could run these classic games on a modern microcontroller, and create a authentic retro experience on a handy portable device.

[Dan] starts by explaining the technology used to make titles like these possible in the days when the wide array of home computer types required a nuanced approach. By separating the story files from the actual interpreter, developers could more easily port the games to various computers. In theory these interpreters, known as “Z-machines”, could be written for any computer that could compile C code, had enough RAM to hold the story, and had a terminal and keyboard. Not exactly the kind of system requirements we’re used to seeing for modern PC games, but it was the 1980’s.

In theory a modern microcontroller will meet these requirements, so [Dan] wanted to create his own Z-machine for one. But rather than “cheat” by using an SD card like previous Arduino Z-machines have, he wanted to see if there was a development board out there that could do it all internally. The answer came in the form of the  Adafruit ItsyBitsy M4 Express, with its 192 kB of RAM and 2 MB of SPI flash.

The Z-machine created by [Dan], which he’s calling A2Z, allows users to run Zork and other compatible interactive text games on the ItsyBitsy without any additional hardware. Just plug the board into your computer and you’ll be able to play the games over the the serial connection. He’s even implemented some retro color schemes to make the experience more authentic, like the blue of the Amiga or Compaq green.

We’ve covered previous projects that brought Zork and friends to the Arduino, your web browser via a virtual Altair 8800, and even some more exotic targets like custom FPGAs. You can play cave adventure, the game that inspired Zork, on the Supercon Badge.

The Desktop Computer Returns As Amiga-Infused Retro Case

The desktop computer is dead. No, I don’t mean computers that are meant to sit either on or underneath a desk. I’m talking about computer cases that are placed on a desk horizontally, probably with a monitor on top. The ‘monitor stand case’ was a mainstay for most of the 80s and 90s, but died out when CRTs became too heavy.

Now, though, there’s an interesting Kickstarter project that aims to bring the desktop computer case back, and it’s doing it as an upgrade to the classic Amiga 500, Amiga 1200, and Amiga 600 computers.

The idea for this project began all the way back in the 80s, with the Checkmate A1500 computer case. This case was designed to add expansion capabilities to the low-end Amiga 500 computer, transforming it into a desktop system with extra floppies, a hard drive, and an expansion port. In effect, you could have a ‘professional’ Amiga system for half the price of Commodore’s product offerings.

Now the Checkmate is back, this time with a case upgrade that will transform an A500, A600, A1200, or even the PPC Aeon Tabor A1222 motherboard. There’s another trick this case has to offer: it’s also compatible with MicroATX and Mini-ITX motherboards, meaning yes, there is now going to be a real desktop case that you can throw a motherboard in and a monitor on top.

The death of the desktop computer is an absolutely tragic tale that has resulted in people dropping towers on a floor and propping up their LCDs on piles of books. The reason why we do this is understandable — when CRTs got too heavy for plastic enclosures, computers became towers. Now, though, we’re all using featherweight LCDs, and computers could easily return to the desktop.

Recreating The Amiga 1200 PCB From Pictures

In the past we’ve talked about one of the major downsides of working with vintage computer hardware, which of course is the fact you’re working with vintage computer hardware. The reality is that these machines were never designed to be up and running 20, 30, or even 40-odd years after they were manufactured. Components degrade and fail, and eventually you’re going to need to either find some way to keep your favorite classic computer up and running or relegate it to becoming a display piece on the shelf.

If you’re like [John Hertell], you take the former option. Knowing that many an Amiga 1200 has gone to that great retrocomputing museum in the sky due to corroded PCBs, he decided to recreate the design from scans of an unpopulated board. While he was at it, he tacked on a few modern fixes and enhancements, earning his new project the moniker: “Re-Amiga 1200”.

To create this updated PCB, [John] took high quality scans of an original board and loaded them up into Sprint Layout, which allows you to freely draw your PCB design over the top of an existing image. While he admits the software isn’t ideal for new designs, the fact that he could literally trace the scan of the original board made it the ideal choice for this particular task.

After the base board was recreated in digital form, the next step was to improve on it. Parts which are now EOL and hard to come by got deleted in place of modern alternatives, power traces were made thicker, extra fan connectors were added, and of course he couldn’t miss the opportunity to add some additional status blinkenlights. [John] has released his Gerber files as well as a complete BOM if you want to make your own Re-Amiga, and says he’ll also be selling PCBs if you don’t want to go through the trouble of getting them fabricated.

It seems as if Amiga fans never say never, as this isn’t the first time we’ve seen one brought back from the brink of extinction by way of a modernized motherboard. Whatever it takes to keep the vintage computing dream alive.

[Thanks to Anders for the tip.]

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