Crusty: The Story Of The Mac SE That Could

January 23, 2024 by Adam Fabio 25 Comments

Retrocomputing often involves careful restorations, rare components, and white gloves. This story involves none of those. This is the story of two people who sought to answer one of the greatest questions in the universe: What does it take to kill a Mac SE?

The star of the show here is Crusty, a Mac SE that was found on the loading dock of a scrap company. It sat out in the weather for at least 6 months, complete with the original leaking lithium battery.

Enter [RadRacer203], who is friends with the owner of this particular scrap company. [RadRacer203] and picked up Crusty, along with a few other classic Macs. He brought these machines to VCF East 2021, where our other hero comes in. [CJ] is something of a magician with CRTs and analog electronics. Trained under [Sark] himself, [CJ] has mastered the 5-finger exploding capacitor technique.

The battery had eaten through the mainboard and even into the chassis. But after a thorough cleaning, the damn thing booted up. Crusty was born.

This Mac was a survivor. Much like Top Gear and their plucky Toyota Hilux, [RadRacer203] and [CJ] devised a plan to put Crusty to the test.

Click through the break for more!

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Brand-New PCB Makes Replica TRS-80 Possible

January 10, 2024 by Dan Maloney 31 Comments

If like us, you missed out on the TRS-80 Model I back when it first came out, relax .With this brand-new PCB that’s a trace-for-trace replica of the original and a bunch of vintage parts, you can build your own from scratch.

Now, obviously, there are easier ways to enjoy the retro goodness that is the 46-year-old machine that in many ways brought the 8-bit hobby computing revolution to the general public’s attention. Sadly, though, original TRS-80s are getting hard to come by, and those that are in decent enough shape to do anything interesting are commanding top dollar. [RetroStack]’s obvious labor of love project provides the foundation upon which to build a brand new TRS-80 as close as possible to the original.

The PCB is revision G and recreates the original in every detail — component layout, connectors, silkscreen, and even trace routing. [RetroStack] even replicated obvious mistakes in the original board, like through-holes that were originally used to fixture the boards for stuffing, and some weird unused vias. There are even wrong components, or at least ones that appear on production assemblies that don’t show up in the schematics. And if you’re going to go through with a build, you’ll want to check out the collection of 3D printable parts that are otherwise unobtainium, such as the bracket for rear panel connectors and miscellaneous keyboard parts.

While we love the devotion to accuracy that [RetroStack] shows with this project, we know that not everyone is of a similar bent. Luckily there are emulators and clones you can build instead. And if you’re wondering why anyone would devote so much effort to half-century-old technology — well, when you know, you know.

Thanks to [Stephen Walters] for the tip.

Feature image: Dave Jones, CC BY-SA 4.0, via Wikimedia Commons

Bringing A Chain Printer Back To Life: The Power Supply

January 8, 2024 by Adam Fabio 25 Comments

[Usagi Electric] has his Centurion minicomputer (and a few others) running like a top. One feature that’s missing, though, is the ability to produce a hard copy. Now, a serious machine like the Centurion demands a serious printer. The answer to that is an ODEC-manufactured printer dressed in proper Centurion blue. This is no ordinary desktop printer, though. It’s a roughly 175lb (80 Kg) beast capable of printing 100 lines per minute. Each line is 132 characters wide, printed on the tractor-feed green bar paper we all associate with old computer systems.

This sort of printer was commonly known as a chain printer, as the letters are on a chain that rides over a series of 66 hammers. Logic on this printer is 74 series logic chips – no custom silicon or LSI (Large Scale Integration) parts on this 47-year-old monster.

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The Sol-1: A 16-bit Computer In 74HC Logic With C Compiler And Unix-like OS

December 11, 2023 by Maya Posch 15 Comments

Sol-1 system pictured from the front. {Credit: Paulo Constantino)

While the concept of a computer system implemented in discrete logic ICs is by itself not among the most original ideas, the way some machines are executed certainly makes them stick out. This is the case with [Paulo Constantino]’s Sol-1, which not only looks extremely professional, but also comes with a lot of amenities that allow for system development, including a C compiler and assembler, a Unix-like OS (in development), DMA, and a whole host of interfaces to interact with the system and peripherals (serial, parallel, IDE, etc.). Not to mention a SystemVerilog model and an emulator, all of which can be found on [Paulo]’s GitHub.

More photos and videos can be found on [Paulo]’s YouTube channel, as well as the Sol-1 website, which shows off the intricate wire wrap work on the back of each PCB. In terms of the ISA, there are 5 general purpose registers (one scratch) which can also be used as two 8-bit registers each. Most operations are supported, except for floating point. For future improvements and additions, Sol-1’s OS will get more features added, and the first major software to be ported to the Sol-1 should be Colossal Cave Adventure and similar text-based adventure (dungeon) games.

Cowgol Development Environment Comes To Z80 And CP/M

December 10, 2023 by Donald Papp 7 Comments

Cowgol on Z80 running CP/M ties together everything needed to provide a Cowgol development environment (including C and assembler) on a Z80 running the CP/M operating system, making it easier to get up and running with a language aimed to be small, bootstrapped, and modern.

Cowgol is an experimental modern language for (very) small systems.

The Zilog Z80 was an 8-bit microprocessor common in embedded systems of the 1970s and 1980s, and CP/M was a contemporary mass-market operating system. As for Cowgol? It’s an Ada-inspired compiler toolchain and programming language aimed at very small systems, such as the Z80.

What’s different about Cowgol is that it is intended to be self-hosted on these small systems; Cowgol is written in itself, and is able to compile itself. Once one has compiled the compiler for a particular target architecture (for example, the Z80) one could then use that compiler on the target system to compile and run programs for itself.

Thankfully, there’s no need to start from scratch. The Cowgol on Z80 running CP/M repository (see the first link of this post) contains the pre-compiled binaries and guidance on using them.

Cowgol is still under development, but it works. It is a modern language well-suited to (very) small systems, and thanks to this project, getting it up and running on a Z80 running CP/M is about as easy as such things can get.

Thanks to [feinfinger] for the tip!

Is Microsoft BASIC Hidden In This Educational Child’s Toy?

November 30, 2023 by Lewin Day 24 Comments

The VTech PreComputer 1000 is a rather ancient toy computer that was available in the distant misty past of 1988. It featured a keyboard and a variety of simple learning games, but does it also feature Microsoft BASIC? [Robin] of 8-Bit Show and Tell dove in to find out.

Officially, the PreComputer was programmable in a form of BASIC, referred to by VTech as PRE-BASIC V1.0. Given that the system has a Z80 CPU and there’s little information in the manual about this programming language, [Robin] was suspicious as to whether it was based on Microsoft BASIC-80. Thus, an examination was in order to figure out just how this BASIC implementation worked, and whether it shared anything with Microsoft’s own effort.

We won’t spoil the conclusions, but there are some strong commonalities between VTech’s BASIC and Microsoft’s version from this era. The variable names in particular are a strong hint as to what’s going on under the hood. The video is worth a watch for anyone that’s a fan of early microcomputer history, BASIC, or just the weird computer-like devices of yesteryear. We also love the idea that the PreComputer 1000 was actually quite a capable machine hiding behind a single-line LCD display.

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Reliving The Authentic 90s Linux Experience

November 8, 2023 by Bryan Cockfield 65 Comments

Installing Linux on a modern PC has never been easier. There are tons of tools available that will nearly-automatically download your Linux distribution of choice, image a USB drive, and make it bootable so you can finally ditch your bloated, privacy-violating operating system and get the free performance boost that comes along with it. This wasn’t always the case, though. In the 90s you had to take a trip to a store (or library) and buy (or borrow) a boxed copy of some variety of Linux on floppy disk or CDs, and then install it on your own, often without the help of the Internet. [Action Retro] demonstrates this process for us so we don’t have to relive the pain ourselves.

Complete with a 90s-era Pentium machine enclosed in a beige case, this is really the full 90s experience. He’s found a boxed version of Red Hat version 5.2 with everything needed to get it up and running and, after a brief issue with the installer crashing because it couldn’t figure out the ZIP disk drive, had another era-appropriate experience by erasing the existing Windows 98 installation. This was before automatic partitioning tools were widely available, so it was a real risk for beginner Linux enthusiasts if they were trying to dual boot.

With the installation complete, the X window system still needed to be set up, as well as making sure the settings for the old CRT monitor were correct. With everything finalized, the system can really be explored. It includes out-of-the-box some software plenty of us would recognize today such as GIMP and some other software we might not, like Netscape Communicator. It’s a real time machine experience to get this operating system running on period-appropriate hardware, and a lot of features of modern Linux systems can still be seen especially if your modern distribution of choice still requires a lot of manual configuration during installation. Old operating systems aside, this machine might be capable of running a modern Linux distribution as well, provided it has something slightly newer than a 486.

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