TRS-80 Model 100 Gets 64-Bit CPU And A Very Wide LCD

January 17, 2021 by Tom Nardi 32 Comments

To say the TRS-80 Model 100 was ahead of its time would be something of an understatement. It had a high-quality mechanical keyboard, phenomenal battery life, plenty of I/O and expansion capabilities, and was actually small and light enough to easily carry around. While its layout might seem to be a bit dated to modern eyes, there’s little debate that it was one of the most successful and influential computers in history.

So it’s little surprise that [belsamber] thought the Model 100 might make an ideal platform for his mobile command line work. With a few modifications, naturally. While technically the nearly 40 year old portable could connect to a Linux computer as a simple serial terminal, its outdated and non-backlit LCD leaves a bit to be desired in 2021. But there’s little sense in upgrading the display if he’d still be saddled with the anemic Intel 80C85 motherboard, so he decided to clean house and replace everything.

Once stripped of the original hardware, the Model 100’s enclosure offered up plenty of room for a Pine A64 LTS single-board computer, four 18650 cells, and a 1920×480 ultra-wide LCD. While not a perfect match for the dimensions of the original panel, the new screen is an exceptionally close fit. The keyboard has been left intact, but rather than adding a QMK-compatible microcontroller to the mix, [belsamber] wired the matrix directly into the GPIO of the A64.

While we know some retro aficionados might shed a tear to see an iconic computer get gutted, [belsamber] mentions that nothing will go to waste; the parts he pulled from this machine will serve as spares for a second Model 100 he has in his collection. Besides, given the immense popularity of these machines, they aren’t exactly rare to begin with.

As an aside, we recently saw this same unique display used in a 3D printed desktop computer with distinctively retro-futuristic styling. We didn’t have miniature 4:1 ratio displays on our list of 2021 hardware predictions, but it seems they’re already making a strong showing.

The Amiga 1000, Still Receiving New Peripherals 35 Years Later

January 8, 2021 by Jenny List 42 Comments

In the world of retrocomputing it’s the earliest models that garner the most interest, usually either due to their rarity, or sometimes just because of their flaws. The Commodore Amiga 1000 is a case in point, it was the machine everybody wanted but its A500 home computer sibling made the Amiga a success story. Peripherals for the 500 are plentiful then, while those for the 1000 remain a rarity. Thus it’s a treat to see an A1000 peripheral appear in the present day, in the form of a memory, clock, and SD card expansion called the Parciero. It packs 8Mb of SRAM to give the Amiga some truly quick fast memory, something that would have used an eye-wateringly expensive brace of chips back in the day but now has just a single package.

We like the description of the Parciero’s case as “about the size of a harmonica that’s been run over by a steam roller“, but it conceals the effect of the march of technology. Amiga enthusiasts are used to their peripherals being chunky affairs full of through-hole chips. Its creator [David Dunklee] is a retired senior US Space Force officer, and we appreciate his humour in the silkscreen layer. It’s a small-scale commercial product, but in a field so select as Amiga 1000 owners it’s unusual enough to make it noteworthy to all retrocomputer enthusiasts by virtue of its mere existence. We congratulate him for helping keep that little corner of vintage technology alive.

The Amiga 1000 may be the original, but it’s possible that it may not be the rarest Amiga.

You Got Something On Your Processor Bus: The Joys Of Hacking ISA And PCI

January 6, 2021 by Maya Posch 32 Comments

Although the ability to expand a home computer with more RAM, storage and other features has been around for as long as home computers exist, it wasn’t until the IBM PC that the concept of a fully open and modular computer system became mainstream. Instead of being limited to a system configuration provided by the manufacturer and a few add-ons that really didn’t integrate well, the concept of expansion cards opened up whole industries as well as a big hobbyist market.

The first IBM PC had five 8-bit expansion slots that were connected directly to the 8088 CPU. With the IBM PC/AT these expansion slots became 16-bit courtesy of the 80286 CPU it was built around. These slots could be used for anything from graphics cards to networking, expanded memory or custom I/O. Though there was no distinct original name for this card edge interface, around the PC/AT era it got referred to as PC bus, as well as AT bus. The name Industry Standard Architecture (ISA) bus is a retronym created by PC clone makers.

With such openness came the ability to relatively easy and cheaply make your own cards for the ISA bus, and the subsequent and equally open PCI bus. To this day this openness allows for a vibrant ecosystem, whether one wishes to build a custom ISA or PCI soundcard, or add USB support to a 1981 IBM PC system.

But what does it take to get started with ISA or PCI expansion cards today? Continue reading “You Got Something On Your Processor Bus: The Joys Of Hacking ISA And PCI” →

Build An 8-bit CPU To Know “But How Do It Know?”

January 2, 2021 by Anool Mahidharia 14 Comments

Sometime around 2009, [J. Clark Scott] published a book aimed to demystify computers for everyone by walking through construction of an 8-bit CPU from scratch. The book had a catchy, but somewhat confusing title But How Do It Know?. The back story on the title goes something like this: Joe is a very nice fellow, but has always been a little slow. He goes into a store where a salesman is standing on a soapbox in front of a group of people. The salesman is pitching the miracle new invention, the Thermos bottle. He is saying, “It keeps hot food hot, and cold food cold….” Joe thinks about this a minute, amazed by this new invention that is able to make a decision about which of two different things it is supposed to do depending on what kind of food you put in it. He can’t contain his curiosity, he is jumping up and down, waving his arm in the air, saying “but, but, but, but…” Finally he blurts out his burning question “But how do it know?” Joe looked at what this Thermos bottle could do, and decided that it must be capable of sensing something about its contents, and then performing a heating or cooling operation accordingly. Joe’s concept of how the bottle worked was far more complicated than the truth. With that introductory opening, [J. Clark Scott] goes on to cover basic number theory, leading on to logic gates, and finally the 8-bit CPU.

[Patrick LeBoutillier] decided to build a hardware version of the CPU/computer as described in [John Clark Scott]’s book. In order to keep size and cost within reasonable bounds, he choose a hybrid construction using a combination of micro-controllers and SN74HC logic IC’s. When used as a companion project alongside reading the book, he hopes people can get their hands dirty and try it out for themselves. He has published a series of 14 videos covering construction of the CPU and the first Introductory video is embedded after the break below. For the micro-controller part of the project, he is using four Arduino Nanos, the code and install instructions for which are available at his Git repo. The Fritzing schematic, also available at the repo, might look a bit daunting at first look, but when you follow along his video series, it becomes easier. You can preview the first three chapters of the book at the “But How Do It Know?” website.

If FPGA’s are more of a thing for you, or you’d like to dip your feet learning FPGA, then [Patrick] has another series of 17 videos (embedded below) where he goes through the same process using a Digilent BASYS3 FPGA development board. These aren’t your only options — if you just want to understand how it works, without having to build the hardware, then check out the online, browser based implementation of the [Clark Scott] CPU.

If it seems the breadboard build of this 8-bit CPU looks complex, then this
Home Made 8-bit CPU Is A Wiry Blinky Build and a veritable rats nest of jumper wires.

Continue reading “Build An 8-bit CPU To Know “But How Do It Know?”” →

Alien Inspired Cyberdeck Packs Vintage Atari 800XL

December 30, 2020 by Tom Nardi 21 Comments

Sticking a Raspberry Pi in a Pelican-style case and calling it a cyberdeck has become something of a meme these days, and while we certainly don’t look down on such projects, we recognize they can get a bit repetitive. But we think this one is unique enough to get a pass. Sure [eizen6] mounted a Pi inside of a rugged waterproof case, but it’s simply serving as a display for the real star of the show: a vintage Atari 800XL computer.

The overall look of the build, from the stenciled Nostromo on the back to the self-destruct warning sticker over the display is a reference to Alien. Partly because both the film and the Atari 800 were released in 1979, but also because [eizen6] says this particular aesthetic is simply the way computers should look. The visual style is also meant to signify that the project embraces the old ways despite the sprinkling of modern technology.

A custom cable lets the 800XL run on USB power.

To that end, retro aficionados will be happy to hear that the Atari appears to be completely unmodified, with [eizen6] going as far as nestling the nearly 40 year old computer in foam rather than permanently mounting it to the case. The various cables for power, video, and data have all been terminated with the appropriate connectors as well, so everything can be easily unplugged should the 8-bit machine need to be returned to more pedestrian use.

In the top half of the case, [eizen6] has mounted the Raspberry Pi 3B+, a seven inch touch screen, a USB hub, and a SIO2SD that allows loading Atari disk images from an SD card. Using a USB capture device, video from the Atari can be shown on the Pi’s display with a simple VLC command. With a USB keyboard plugged into the hub, the Pi can be put to more advanced use should the need arise. It’s also worth noting that, thanks to a custom cable, the Atari is running off of a USB power bank. With a second USB power bank dedicated to running the Pi and its LCD display, this retro cyberdeck is fully mobile.

We’ve seen plenty of modern builds that try and recapture the look and feel of retro computers, but very few that actually integrate the genuine article. While the aesthetic might not be everyone’s cup of tea, we can all appreciate the respect shown for the original hardware in this build.

Amiga Now Includes HDMI By Way Of A Raspberry Pi Daughterboard

December 30, 2020 by Jenny List 34 Comments

If you had an Amiga during the 16-bit home computer era it’s possible that alongside the games and a bit of audio sampling you had selected it because of its impressive video capabilities. In its heyday the Amiga produced broadcast-quality graphics that could even be seen on more than a few TV shows from the late 1980s and early 1990s. It’s fair to say though that the world of TV has moved on since the era of Guru Meditation, and an SD video signal just won’t cut it anymore. With HDMI as today’s connectivity standard, [c0pperdragon] is here to help by way of a handy HDMI upgrade that taps into the digital signals direct from the Amiga’s Denise chip.

At first thought one might imagine that an FPGA would be involved, however instead the signals are brought out via a daughterboard to the expansion header of a Raspberry Pi Zero. Just remove the DENISE display encoder chip and pop in the board with uses a long-pinned machined DIP socket to make the connections. The Pi runs software from the RGBtoHDMI project originally created with the BBC Micro in mind, to render pixel-perfect representations of the Amiga graphics on the Pi’s HDMI output. The caveat is that it runs on the original chipset Amigas and only some models with the enhanced chipset, so it seems Amiga 600 owners are left in the cold. A very low latency is claimed, which should compare favourably with some other solutions to the same problem.

This isn’t the first time we’ve seen an HDMI Amiga conversion, but it’s one that’s usable on more than simply the big-box machines.

Continue reading “Amiga Now Includes HDMI By Way Of A Raspberry Pi Daughterboard” →

Think Your Laptop Is Anemic? Try An MSDOS One

December 28, 2020 by Al Williams 51 Comments

If someone gifted you a cheap laptop this holiday season, you might be a little put out by the 2GB of RAM and the 400 MHz CPU. However, you might appreciate it more once you look at [Noel’s Retro Lab’s] 4.8 Kg Amstrad PPC512 He shows it off inside and out in the video below.

Unlike a modern laptop, this oldie but goodie has a full keyboard that swings out of the main body. The space below the keyboard contains the LCD screen, which [Noel] is going to have to replace with an LCD from another unit that was in worse shape but had a good-looking screen. In this video, he gets as far as getting video output to an external monitor, but neither LCD shows any sign of life. But he’s planning more videos soon.

Continue reading “Think Your Laptop Is Anemic? Try An MSDOS One” →