Although BASIC was most commonly used on home computers like the Commodore VIC-20, it was possible to write programs in other languages, such as Forth. Conveniently, all it took to set up a Forth development system was inserting the cartridge into the VIC-20 and powering it on, with the VIC-FORTH cartridge by [Tom Zimmer] being a popular choice for the Commodore VIC-20. In a recent video, the [My Developer Thoughts] YouTube channel covers Forth development using this cartridge.
In addition to the video tutorial, the original VIC-FORTH Instruction Manual is also available, together with the 1541 disk image. In an upcoming video, the Commodore 64 version of the cartridge will also be covered, which is called 64Forth, and which is also readily available to tinker with. For those interested in learning more about [Tom Zimmer] and his Forth-related work, a 2010 interview could be interesting. This covers the other platforms which he developed an implementation for.
As for why Forth might be interesting to developers and users, this comes mostly down to the much lower overhead of Forth compared to BASIC, while avoiding the pitfalls of ASM and resource-intensive nature of developing in C, as the entire Forth development system (compiler, editor, etc.) comfortably fits in the limited memory of the average 8-bit home computer.
In a recent episode of [The Retro Shack], a new Commodore VIC-20 is built, using a ‘Vicky Twenty’ replacement PCB by [Bob’s Bits] as the base and as many new components as could be found. The occasion for this was that a viewer had sent in a VIC-20 that turned out to be broken, so in order to diagnose it, building a new one with known working parts seemed incredibly useful.
Advantages of the reproduction PCB are a number of board-level fixes that negate the need for certain bodge wires, while also having footprints for a wider range of round DIN connectors. The non-proprietary ICs were obtained along with other standard parts from a retro computing store, while the proprietary Commodore components were scrounged up from your friendly used component selling sites.
The result is what from the outside looks like a genuine VIC-20, and which should prove to be very useful in diagnosing the broken VIC-20 system in the future, as well as presumably to play some games on.
This year marks the anniversary of the most popular selling home computer ever, the Commodore 64, which made its debut in 1982. Note that I am saying “home computer” and not personal computer (PC) because back then the term PC was not yet in use for home computer users.
Some of you have probably not heard of Commodore, which is kind of sad, though there is a simple reason why — Commodore is no longer around to maintain its legacy. If one were to watch a documentary about the 1980s they may see a picture of an Apple computer or its founders but most likely would not see a picture of a Commodore computer in spite of selling tens of millions of units.
To understand the success of the C64 I would first back up and talk about the fabled era of home computers which starts with understanding the microprocessor of the day, the venerable 6502. Check out the video and follow along below.
Those of us who were around in the late 70s and into the 80s might remember the Speak & Spell, a children’s toy with a remarkable text-to-speech synthesizer. While it sounds dated by today’s standards, it was revolutionary for the time and was riding a wave of text-to-speech functionality that was starting to arrive to various computers of the era. While a lot of them used dedicated hardware to perform the speech synthesis, some computers were powerful enough to do this in software, but others were not quite able. The VIC-20 was one of the latter, but thanks to an ESP8266 it has been retroactively given this function.
This project comes to us from [Jan Derogee], a connoisseur of this retrocomputer, and builds on the work by [Earle F. Philhower] who ported the retro speech synthesis software known as SAM from assembly to C which made it possible to run on the ESP8266. Audio playback is handled on the I2S port, but some work needed to be done to get this to work smoothly since this port also handles the communication with the VIC-20. Once this was sorted out, a patch was made to be able to hear the computer’s audio as well as the speech synthesizer’s. Finally, a serial command interface was designed by [Jan] which allows for control of the module.
While not many of us have VIC-20s sitting at home, it’s still an interesting project that shows the broad scope of a small and inexpensive chip like the ESP8266 which would have had a hefty price tag back in the 1980s. If you have other 80s hardware laying around waiting to be put to work, though, take a look at this project which brings new vocabulary words to that old classic Speak & Spell.
Imagine the ultimate homage to 1980s 8-bit home computers. It might look like [David Murray] aka The 8-Bit Guy’s Commander X16.
As a core group of geeks, hackers, and developers age, we yearn for the computers of our youth. VIC-20s, Commodore Pets, 64s, 128s, Ataris, Apple IIes, and the list goes on and on. For many of us, our first hands on experience with a computer was with such a machine that is now called “retro”. Sadly, many of these relics are getting more expensive as demand increases and supplies dwindle. Working examples are harder to find, and even those can break down. Original monitors, peripherals, and accessories are also getting scarcer. This is all quite understandable when we consider that some of these classics are over 40 years old.
What was it that we loved about these old rigs that makes them so attractive? [David] decided to distil what makes a classic a classic, and then turn that list into a spec list for what he calls his “Dream Computer”. He found that things like a printed and spiral bound manual were a big part of the charm and utility of these early home computers. Booting directly to a prompt and being able to directly control the hardware was another highly desirable trait.
[David] also took the time to determine what people don’t like about these retro machines: Wacky keyboard layouts, composite video output, and glacially slow storage. Swapping multiple floppies to load a program or respooling a cassette tape is just as undesirable in 2021 as it was in 1981. Who knew?
The X16’s’ prototyping is still in progress.
The result of [David]’s research is the Commander X16. Inspired by the VIC-20, it’s a fresh take on the retrocomputer that only uses parts that are currently available. You can see the first video in a series about the development of the X16 below the break. Be aware that a lot of progress has been made since the video came out in 2019, but it still provides an excellent starting point for learning about the project.
The X16’s specifications read like dream list made in the mid 80s: 256 color VGA, up to 2MB memory, an 8 MHz 6502, plenty of expansion ports, and even ports for SNES style controllers. And what else will this dream machine include? You guessed it: A spiral bound manual!
It’s not possible to list all of the great features of the X16 in this space, so check out the Commander X16 FAQ for all the details. If this project makes your heart go pitter patter, you may be interested to know that they need help with software development! An emulator is available for development. The goal is to have a healthy software ecosystem in place when the X16 launches.
Commodore machines are well-loved around here, but usually when you think Commodore, you think about the Commodore 64, or maybe the PET or Amiga. But the Commodore 64 had an older sister, the VIC 20. This was the first computer to sell a million units and has a lot in common with its better-known successor. The machine was only made for a few years, and [Dubious Engineering] has been restoring one over a few videos. In the video below, he opens it up for a look inside, among other things.
If you want to get straight to the opening, you’ll need to fast forward about 5 and a half minutes. The keyboard pulls off and a nice old-fashioned set of cables made from individual wires connect to the skinny main board with all the smarts on it. No ribbon cables or flex PCBs!
Satoru Iwata is perhaps best remembered for leading Nintendo through the development of the DS and Wii, two wildly successful systems which undeniably helped bring gaming to a wider and more mainstream audience. But decades before becoming the company’s President in 2002, he got his start in the industry as a developer working on many early console and computer games. [Robin Harbron] recently decided to dig into one of the Iwata’s earliest projects, Star Battle for the VIC-20.
Finding the message was easy, if you knew were to look.
It’s been known for some time that Iwata, then just 22 years old, had hidden his name and a message in the game’s source code. But [Robin] wondered if there was more to the story. Looking at the text in memory, he noticed the lines were actually null-terminated. Realizing the message was likely intended to get printed on the screen at one point during the game’s development, he started hunting for a way to trigger the nearly 40 year old Easter Egg.
As it turns out, it’s hidden behind a single flag in the code. Just change it from 0 to 1, and the game will display Iwata’s long-hidden credit screen. That proved the message was originally intended to be visible to players, but it still didn’t explain how they were supposed to trigger it during normal game play.
That’s where things really get interesting. As [Robin] gives us a guided tour through Star Battle’s inner workings, he explains that Iwata originally intended the player to hit a special combination of keys to tick over the Easter Egg’s enable flag. All of the code is still there in the commercial release of the game, but it’s been disabled. As Iwata’s life was tragically cut short in 2015 due to complications from cancer, we’ll perhaps never know the reason he commented out the code in question before the game was released. But at least we can now finally see this hidden message from one of gaming’s true luminaries.
