Blinkenlights-First Retrocomputer Design

January 11, 2025 by Elliot Williams 10 Comments

[Boz] wants to build a retrocomputer, but where to start? You could start with the computery bits, like say the CPU or the bus architecture, but where’s the fun in that? Instead, [Boz] built a righteous blinkenlights array.

What’s cool about this display is that it’s ready to go out of the box. All of the LEDs are reverse-mount and assembled by the board maker. The 19″ 2U PCBs serve as the front plates, so [Boz] was careful not to use any through-hole parts, which also simplified the PCB assembly, of course. Each slice has its own microcontroller and a few shift registers to get the bits lit up, and that’s all there is to it. They take incoming data at 9600 baud and output blinkiness.

Right now it pulls out its bytes from his NAS. We’re not sure which bytes, and we think we see some counters in there. Anyway, it doesn’t matter because it’s so pretty. And maybe someday the prettiness will lure [Boz] into building a retrocomputer to go under it. But honestly, we’d just relax and watch the blinking lights.

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SerenityOS On Real Hardware

January 10, 2025 by Jenny List 8 Comments

One of the problems facing any developer working on their own operating system is that of hardware support. With many thousands of peripherals and components that can be found in a modern computer, keeping up requires either the commercial resources of Microsoft or the huge community of Linux.

For a small project such as SerenityOS this becomes a difficult task, and for that reason the primary way to run that OS has always been in an emulator. [Sdomi] however has other ideas, and has put a lot of effort to getting the OS to run on some real hardware. The path to that final picture of a laptop with a SerenityOS desktop is long, but it makes for a fascinating read.

The hardware in question is an Intel powered Dell Chromebook. An odd choice you might think, but they’re cheap and readily available, and they have some useful debugging abilities built in. We’re treated to an exploration of the hardware and finding those debug ports, and since the USB debugging doesn’t work, a Pi Pico clone is squeezed into the case. We like that it’s wired up to the flash chip as well as serial.

Getting access to the serial port from the software turned out to be something of a pain, because the emulated UART wasn’t on the port you’d expect. Though it’s an Intel machine it’s not a PC clone, so it has no need. Some epic hackery involving rerouting serial to the PC debug port ensued, enabling work to start on an MMC driver for the platform. The eventual result is a very exclusive laptop, maybe the only one running SerenityOS on hardware.

We like this OS, and we hope this work will lead to it becoming usable on more platforms. We took a look at it back in 2023, and it’s good to hear that it’s moving forward.

One To Watch For In 2025: Tanmatsu

January 7, 2025 by Jenny List 20 Comments

If you’ve used the Espressif series of processors, perhaps you’ll have heard of their upcoming ESP32-P4. This is an application processor, with dual RISC-V cores at 400 MHz, and save for a lack of an MMU, a spec sheet much closer to the kind of silicon you’d find in single board computers with pretensions towards being a mini-PC.

It was announced a year ago and there have been limited numbers of pre-release versions of the chip available to developers, but thus far there have been very few boards featuring it. We’re excited then to note that a P4-based board we’ve been watching for a while is finally breaking cover, and what’s more, you can now pre-order one.

The Tanmatsu (Japanese for “Terminal”) is an all-in-one palmtop computer for hackers, with a QWERTY keyboard and an 800×480 DSI display. It’s designed with plenty of expansion in mind, and it’s got space on board for a LoRa radio. The reason we’re interested is that it comes from some of our friends in the world of event badges, so we’ve seen and handled real working prototypes, and we know that its makers come from a team with a proven record in manufacture and delivery of working hardware. The prototype we saw had hardware that was very close to the final version, and an operating system and software that was still under development but on track for the April release of the device. It will be fully open-source in both hardware and software.

We liked what we saw and have pre-ordered one ourselves, so we’ll be sure to bring you a closer look when it arrives.

The Ultimate Distraction Free Writing Environment

January 2, 2025 by Jenny List 42 Comments

The art of writing has become a cluttered one to follow, typically these days through a graphical word processor. There may be a virtual page in front of you, but it’s encumbered by much UI annoyance. To combat this a variety of distraction free software and appliances have been created over the years.

But it’s perhaps [Liam Proven]’s one we like the most — it’s a bootable 16-bit DOS environment with a selection of simple text and office packages on board. No worries about being distracted by social media when you don’t even have networking.

The zip file, in the releases section of the repository, is based upon SvarDOS, and comes with some software we well remember from back in the day. There’s MS Word 5.5 for DOS, in the public domain since it was released as a Y2K fix, Arnor Protext, and the venerable AsEasyAs spreadsheet alongside a few we’re less familiar with. He makes the point that a machine with a BIOS is required, but those of you unwilling to enable BIOS emulation on a newer machine should be able to run it in a VM or an emulator. Perhaps it’s one to take on the road with us, and bang away in DOS alongside all the high-powered executives on the train with their fancy business projections.

We recently talked about SvarDOS, and it shouldn’t come as a surprise that our article linked to a piece [Liam] wrote for The Register.

An animated GIF of Engineer Bo's Precision Bluetooth Scroll Wheel wirelessly, and effortlessly scrolling down the Hack A Day blog with a single finger

Doomscroll Precisely, And Wirelessly

December 31, 2024 by Michael Shaub 18 Comments

Around here, we love it when someone identifies a need and creates their own solution. In this case, [Engineer Bo] was tired of endless and imprecise scrolling with a mouse wheel. No off-the-shelf solutions were found, and other DIY projects either just used hacked mice scroll wheels, customer electronics with low-res hardware encoders, or featured high-res encoders that were down-sampled to low-resolution. A custom build was clearly required.

We loved seeing hacks along the whole process by [Engineer Bo], working with components on hand, pairing sensors to microcontrollers to HID settings, 3D printing forms to test ergonomics, and finishing the prototype device. When 3D printing, [Engineer Bo] inserted a pause after support material to allow drawing a layer of permanent marker ink that acts as a release agent that can later be cleaned with rubbing alcohol.

We also liked the detail of a single hole inside used to install each of the three screws that secure the knob to the base. While a chisel and UV-curing resin cleaned up some larger issues with the print, more finishing was required. For a project within a project, [Engineer Bo] then threw together a mini lathe with 3D printed and RC parts to make sanding easy.

Scroll down with your clunky device to see the video that illustrates the precision with a graphic of a 0.09° rotation and is filled with hacky nuggets. See how the electronics were selected and the circuit designed and programmed, the use of PCBWay’s CNC machining in addition to board assembly services, and how to deal with bearings that spin too freely. [Engineer Bo] teases that a future version might use a larger bearing for less wobble and an anti-slip coating on the base. Will the board files and 3D models be released, too? Will these be sold as finished products or kits? Will those unused LED drivers be utilized in an upcoming version? We can’t wait to see what’s next for this project.

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Magic Eye Images In Your Spreadsheet

December 8, 2024 by Jenny List 56 Comments

Ah, the 1990s. It was a simpler time, when the web was going to be democratic and decentralised, you could connect your Windows 95 PC to the internet without worrying much about it being compromised, and freely download those rave music MP3s. Perhaps you had a Global Hypercolor T-shirt and spent a summer looking like the sweaty idiot you were, and it’s certain you desperately squinted at a magic eye image in a newspaper (remember newspapers?) trying to see the elephant or whatever it was. If you’d like to relive that experience, then [Dave Richeson] has a magic eye image generator for Microsoft Excel.

Unfortunately a proportion of the population including your scribe lack the ability to see these images, a seemingly noise-like pattern of dots on the page computationally generated to fool the visual processing portion of your brain to generate a 3D image. The Excel sheet allows you to create the images, but perhaps most interesting is the explanation of the phenomenon and mathematics which go along with it. Along with a set of test images depicting mathematical subjects, it’s definitely worth a look.

You can download a template and follow the instructions, and from very limited testing here we can see that LibreOffice doesn’t turn its nose up at it, either. Give it a go, and learn afresh the annoyance of trying to unfocus your eyes.

Sniffing Around Inside A ThinkPad Battery

December 4, 2024 by Tom Nardi 24 Comments

For most people, a battery pack that’s misbehaving simply means it’s time to get a new battery. But when the battery in their ThinkPad wasn’t able to muster up more than 20 minutes of runtime, [Shrinath Nimare] saw an opportunity to dig deeper and do a bit of investigating.

The problem seemed to be that the battery pack was reporting that it was 100% charged at just 11.7 V instead of the correct 12.3 V. As it turns out, that 11.7 V figure is only slightly above what the battery should be when its run flat — so in reality, the battery was never actually getting a charge and would report that it was dead after just a few minutes of use. But why?

With a logic analyzer attached to the pins of the battery, [Shrinath] set out to sniff its communications with the ThinkPad. Even if it wouldn’t lead to fixing the battery pack, the information obtained would potentially be useful for other projects, such as creating a custom high-capacity LiFePO4 pack down the line.

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