2025-12-07 23:00:34
There are plenty of well-known models among the 8-bit machines of the 1980s, and most readers could rattle them off without a thought. They were merely the stars among a plethora of others, and even for a seasoned follower of the retrocomputing world, there are fresh models from foreign markets that continue to surprise and delight. [Dave Collins] is treating us to an in-depth look at the VTech VZ-200, a budget machine that did particularly well in Asian markets. On the way, we learn a lot about a very cleverly designed machine.
The meat of the design centres not around the Z80 microprocessor or the 6847 video chip, but the three 74LS chips handling both address decoding and timing for video RAM access. That they managed this with only three devices is the exceptionally clever part. While there are some compromises similar to other minimalist machines in what memory ranges can be addressed, they are not sufficient to derail the experience.
Perhaps the most ingenuity comes in using not just the logic functions of the chips, but their timings. The designers of this circuit really knew the devices and used them to their full potential. Here in 2025, this is something novice designers using FPGAs have to learn; back then, it was learned the hard way on the breadboard.
All in all, it’s a fascinating read from a digital logic perspective as much as a retrocomputing one. If you want more, it seems this isn’t the only hacker-friendly VTech machine.
John Dalton, CC BY-SA 3.0.
2025-12-07 20:00:49
Plotters aren’t as common as they once were. Today, many printers can get high enough resolution with dots that drawing things with a pen isn’t as necessary as it once was. But certainly you’ve at least seen or heard of machines that would draw graphics using a pen. Most of them were conceptually like a 3D printer with a pen instead of a hotend and no real Z-axis. But as [biosrhythm] reminds us, some plotters were suspiciously like typewriters fitted with pens.
Instead of type bars, type balls, or daisy wheels, machines like the Panasonic Penwriter used a pen to draw your text on the page, as you can see in the video below. Some models had direct computer control via a serial port, if you wanted to plot using software. At least one model included a white pen so you could cover up any mistakes.
If you didn’t have a computer, the machine had its own way to input data for graphs. How did that work? Read for yourself.
Panasonic wasn’t the only game in town, either. Silver Reed — a familiar name in old printers — had a similar model that could connect via a parallel port. Other familiar names are Smith Corona, Brother, Sharp, and Sears.
Since all the machines take the same pens, they probably have very similar insides. According to the post, Alps was the actual manufacturer of the internal plotting mechanism, at least.
The video doesn’t show it, but the machines would draw little letters just as well as graphics. Maybe better since you could change font sizes and shapes without switching a ball. They could even “type” vertically or at an angle, at least with external software.
Since plotters are, at heart, close to 3D printers, it is pretty easy to build one these days. If plotting from keystrokes is too mundane for you, try voice control.
2025-12-07 17:00:58
The ZX Spectrum is known for a lot of things, but it’s not really known for a rich and deep library of FPS titles. However, there is finally such a game for the platform, thanks to [Jakub Trznadel]—and it’s called World of Spells.
Like so many other games of this type, it was inspired by the 3D raycasting techniques made so popular by Wolfenstein 3D back in the day. For that reason, it has a very similar look in some regards, but a very different look in others—the latter mostly due to the characteristic palette available on the ZX Spectrum. A playable FPS is quite a feat to achieve on such limited hardware, but [Jakub] pulled it off well, with the engine able to reach up to 80 frames per second.
The game is available for download, and you can even order it on tape if you so desire. You might also like to check out the walkthrough on YouTube, where the game is played on an emulator. Don’t worry, though—the game works on real ZX Spectrum 48k hardware just fine.
The Speccy retains a diehard fanbase to this day. You can even build a brand new one thanks to a buoyant supply of aftermarket parts.
[thanks to losr for the tip!]
2025-12-07 14:00:58
[joppedc] wrote in to let us know that the Formula 1® season is coming to an end, and that the final race should be bangin’. To get ready, he built this ultra-sleek logo light box last week that does more than just sit there looking good, although it does that pretty well. This light box reacts to live race events, flashing yellow for safety cars, red for red flags, and green for, well, green flags.
The excellent light box itself was modeled in Fusion 360, and the files are available on MakerWorld. The design is split into four parts — the main body, a backplate to mount the LEDs, the translucent front plate, and an enclosure for an ESP32.
Doing it this way allowed [joppedc] to not only print in manageable pieces, it also allowed him to use different materials. Getting the front panel to diffuse light correctly took some experimenting to find the right thickness. Eventually, [joppedc] landed on 0.4 mm (two layers) of matte white PLA.
There isn’t much in the way of brains behind this beauty, just an ESP32, a strip of WS2812B addressable LEDs, and a USB-C port for power. But it’s the software stack that ties everything together. The ESP32 has WLED, Home Assistant runs the show, and of course, there is the F1 sensor integration to get live race data.
If you’re looking for more of an F1 dashboard, then we’ve got you covered.
2025-12-07 11:00:58
USB PD is a fun protocol to explore, but it can be a bit complex to fully implement. It makes sense we’re seeing new stacks pop up all the time, and today’s stack is a cool one as far as code reusability goes. [Vitaly] over on Hackaday.io brings us pdsink – a C++ based PD stack with no platform dependencies, and fully-featured sink capabilities.
This stack can do SPR (5/9/15/20V) just like you’d expect, but it also does PPS without breaking a sweat – perfect for your Lithium Ion battery charging or any other current-limited shenanigans. What’s more, it can do EPR (28V and up) – for all your high-power needs. For reference, the SPR/PPS/EPR combination is all you could need from a PD stack intended for fully taking advantage of any USB-PD charger’s capabilities. The stack is currently tailored to the classic FUSB302, but [Vitaly] says it wouldn’t be hard to add support for a PD PHY chip of your choice.
It’s nice to have a choice in how you want your PD interactions to go – we’ve covered a few stacks before, and each of them has strong and weak sides. Now, if you have the CPU bandwidth, you could go seriously low-tech and talk PD with just a few resistors, transistors, and GPIOs! Need to debug a particular USB-C edge case? Don’t forget a logger.
2025-12-07 08:00:10
[Michael Lynch] recently decided to delve into the world of off-grid, decentralized communications with MeshCore, because being able to communicate wirelessly with others in a way that does not depend on traditional communication infrastructure is pretty compelling. After getting his hands on a variety of hardware and trying things out, he wrote up his thoughts from the perspective of a hardware-curious software developer.
He ends up testing a variety of things: MeshCore firmware installed on a Heltec V3 board (used via an app over Bluetooth), a similar standalone device with antenna and battery built in (SenseCAP T-1000e, left in the header image), and a Lilygo T-Deck+ (right in the header image above). These all use MeshCore, which is built on and reportedly compatible with Meshtastic, a framework we have featured in the past.
The first two devices are essentially MeshCore gateways, to which the user connects over Bluetooth. The T-Deck is a standalone device that resembles a Blackberry, complete with screen and keypad. [Michael] dove into what it was like to get them up and running.
Probably his most significant takeaway was that the whole process of onboarding seemed a lot more difficult and much less clear than it could be. This is an experience many of us can relate to: the fragmented documentation that exists seems written both by and for people who are already intimately familiar with the project in its entirety.
Another thing he learned was that while LoRa is a fantastic technology capable of communicating wirelessly over great distances with low power, those results require good antennas and line of sight. In a typical urban-ish environment, range is going to be much more limited. [Michael] was able to get a maximum range of about five blocks between two devices. Range could be improved by purchasing and installing repeaters or by having more devices online and in range of one another, but that’s where [Michael] drew the line. He felt he had gotten a pretty good idea of the state of things by then, and not being a radio expert, he declined to purchase repeater hardware without any real sense of where he should put them, or what performance gains he could expect by doing so.
Probably the most surprising discovery was that MeshCore is not entirely open source, which seems odd for an off-grid decentralized communications framework. Some parts are open, but the official clients (the mobile apps, web app, and T-Deck firmware) are not. [Michael] found this out when, being primarily a software developer, he took a look at the code to see if there was anything he could do to improve the poor user experience on the T-Deck and found that the firmware was proprietary.
[Michael]’s big takeaway as a hardware-curious software developer is that the concept is great and accessible (hardware is not expensive and there is no licensing requirement for LoRa), but it’s not really there yet in terms of whether it’s practical for someone to buy a few to distribute among friends for use in an emergency. Not without getting into setting up enough repeaters to ensure connectivity, anyway.
