A New Screen Upgrade For The GBA

August 27, 2025 by 8 Comments

The Game Boy Advance (GBA) was released in 2001 to breathe some new life into the handheld market, and it did it with remarkable success. Unfortunately, the original models had a glaring problem: their unlit LCD screens could be very difficult to see. For that reason, console modders who work on these systems tend to improve the screen first like this project which brings a few other upgrades as well.

The fully open-source modification is called the Open AGB Display and brings an IPS display to the classic console. The new screen has 480×480 resolution which is slightly larger than the original resolution but handles upscaling with no noticeable artifacts and even supports adding some back in like scanlines and pixelation to keep the early 00s aesthetic. The build does require permanently modifying the case though, but for the original GBA we don’t see much downside. [Tobi] also goes through a ton of detail on how the mod works as well, for those who want to take a deep dive into the background theory.

There has been a lot of activity in the Game Boy Advance communities lately though as the hardware and software become more understood. If you don’t want to modify original hardware, want an upgraded experience, but still want to use the original game cartridges we might recommend something like the Game Bub instead.

Homebrew Tire Pressure Monitoring System

August 27, 2025 by 52 Comments

When [upir] saw that you could buy tire valve stem caps that read pressure electronically, he decided to roll his own Tire Pressure Monitoring System (TPMS) like the one found on modern cars. An ESP32 and an OLED display read the pressure values. He didn’t have a car tire on his workbench though, so he had to improvise there.

Of course, a real TPMS sensor goes inside the tire, but screwing them on the valve stem is much easier to deal with. The sensors use Bluetooth Low Energy and take tiny batteries. In theory, you’re supposed to connect to them to your phone, although two different apps failed to find the sensors. Even a BLE scanner app wouldn’t pick them up. Turns out — and this makes sense — the sensors don’t send data if there’s no pressure on them, so as not to run down the batteries. Putting pressure on them made them pop up on the scanner.

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The Android Bluetooth Connection

August 27, 2025 by 14 Comments

Suppose someone came to talk to you and said, “I need your help. I have a Raspberry Pi-based robot and I want to develop a custom Android app to control it.” If you are like me, you’ll think about having to get the Android developer tools updated, and you’ll wonder if you remember exactly how to sign a manifest. Not an appealing thought. Sure, you can buy things off the shelf that make it easier, but then it isn’t custom, and you have to accept how it works. But it turns out that for simple things, you can use an old Google Labs project that is, surprisingly, still active and works well: MIT’s App Inventor — which, unfortunately, should have the acronym AI, but I’ll just call it Inventor to avoid confusion.

What’s Inventor? It lives in your browser. You lay out a fake phone screen using drag and drop, much like you’d use QT Designer or Visual Basic. You can switch views and attach actions using a block language sort of like Scratch. You can debug in an emulator or on your live phone wirelessly. Then, when you are ready, you can drop an APK file ready for people to download. Do you prefer an iPhone? There’s some support for it, although that’s not as mature. In particular, it appears that you can’t easily share an iPhone app with others.

Is it perfect? No, there are some quirks. But it works well and, with a little patience, can make amazingly good apps. Are they as efficient as some handcrafted masterpiece? Probably not. Does it matter? Probably not. I think it gets a bad rep because of the colorful blocks. Surely it’s made for kids. Well, honestly, it is. But it does a fine job, and just like TinkerCad or Lego, it is simple enough for kids, but you can use it to do some pretty amazing things.

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Lynx-R1 Headset Makers Release 6DoF SLAM Solution As Open Source

August 27, 2025 by 8 Comments

Some readers may recall the Lynx-R1 headset — it was conceived as an Android virtual reality (VR) and mixed reality (MR) headset with built-in hand tracking, designed to be open where others were closed, allowing developers and users access to inner workings in defiance of walled gardens. It looked very promising, with features rivaling (or surpassing) those of its contemporaries.

Founder [Stan Larroque] recently announced that Lynx’s 6DoF SLAM (simultaneous location and mapping) solution has been released as open source. ORB-SLAM3, modified for Android-based hardware (GitHub repository), takes in camera images and outputs a 6DoF pose, and does so effectively in real-time. The repository contains some added details as well as a demo application that can run on the Lynx-R1 headset.

The unusual optics are memorable. (Hands-on Lynx-R1 by Antony Vitillo)

As a headset the Lynx-R1 had a number of intriguing elements. The unusual optics, the flip-up design, and built-in hand tracking were impressive for its time, as was the high-quality mixed reality pass-through. That last feature refers to the headset using its external cameras as inputs to let the user see the real world, but with the ability to have virtual elements displayed and apparently anchored to real-world locations. Doing this depends heavily on the headset being able to track its position in the real world with both high accuracy and low latency, and this is what ORB-SLAM3 provides.

A successful crowdfunding campaign for the Lynx-R1 in 2021 showed that a significant number of people were on board with what Lynx was offering, but developing brand new consumer hardware is a challenging road for many reasons unrelated to developing the actual thing. There was a hands-on at a trade show in 2021 and units were originally intended to ship out in 2022, but sadly that didn’t happen. Units still occasionally trickle out to backers and pre-orders according to the unofficial Discord, but it’s safe to say things didn’t really go as planned for the R1.

It remains a genuinely noteworthy piece of hardware, especially considering it was not a product of one of the tech giants. If we manage to get our hands on one of them, we’ll certainly give you a good look at it.

A preproduction U1 sitting on a workbench

A Tool-changing 3D Printer For The Masses

August 27, 2025 by 26 Comments

Modern multi-material printers certainly have their advantages, but all that purging has a way to add up to oodles of waste. Tool-changing printers offer a way to do multi-material prints without the purge waste, but at the cost of complexity. Plastic’s cheap, though, so the logic has been that you could never save enough on materials cost to make up for the added capital cost of a tool-changer — that is, until now.

Currently active on Kickstarter, the Snapmaker U1 promises to change that equation. [Albert] got his hands on a pre-production prototype for a review on 247Printing, and what we see looks promising.

The printer features the ubiquitous 235 mm x 235 mm bed size — pretty much the standard for a printer these days, but quite a lot smaller than the bed of what’s arguably the machine’s closest competition, the tool-changing Prusa XL. On the other hand, at under one thousand US dollars, it’s one quarter the price of Prusa’s top of the line offering. Compared to the XL, it’s faster in every operation, from heating the bed and nozzle to actual printing and even head swapping. That said, as you’d expect from Prusa, the XL comes dialed-in for perfect prints in a way that Snapmaker doesn’t manage — particularly for TPU. You’re also limited to four tool heads, compared to the five supported by the Prusa XL.

The U1 is also faster in multi-material than its price-equivalent competitors from Bambu Lab, up to two to three times shorter print times, depending on the print. It’s worth noting that the actual print speed is comparable, but the Snapmaker takes the lead when you factor in all the time wasted purging and changing filaments.

The assisted spool loading on the sides of the machine uses RFID tags to automatically track the colour and material of Snapmaker filament. That feature seems to take a certain inspiration from the Bambu Labs Mini-AMS, but it is an area [Albert] identifies as needing particular attention from Snapmaker. In the beta configuration he got his hands on, it only loads filament about 50% of the time. One can only imagine the final production models will do better than that!

In spite of that, [Albert] says he’s backing the Kickstarter. Given Snapmaker is an established company — we featured an earlier Snapmaker CNC/Printer/Laser combo machine back in 2021— that’s less of a risk than it could be.

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A view of the schematics for each major component.

Simulating The Commodore PET

August 26, 2025 by 2 Comments

Over on his blog our hacker [cpt_tom] shows us how to simulate the hardware for a Commodore PET. Two of them in fact, one with static RAM and the other with dynamic RAM.

This project is serious business. The simulation environment used is Digital. Digital is a digital logic designer and circuit simulator designed for educational purposes. It’s a Java program that runs under the JVM. It deals in .dig files which are XML files that represent the details of the simulated hardware components. You don’t need to write the XML files by hand, there is a GUI for that. Continue reading “Simulating The Commodore PET” →