Author: Al Williams

4566 Articles

Rusting An E-scooter (In A Good Way)

September 13, 2026 by 4 Comments

It is a classic Hackaday situation. You have an Egret GT E-scooter. It has a screen that shows the usual dash stats, but that led to an annoyance. You could accidentally enter firmware update mode and, from there, enter operational mode without the security PIN. [Ben] couldn’t let that stand, so he reverse-engineered the protocol and rewrote the firmware in Rust. As he put it, “… because I have to break… everything I own…” We get it.

The mobile app was useful for some basic info, since sniffing Bluetooth is fairly easy and analyzing mobile code is, more or less, straightforward. Analysis revealed some data that doesn’t show on the display and that several things are sent back to home base tagged with the scooter’s unique ID — another reason to gut the existing firmware.

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Tech In Plain Sight: Meet The Robot That Does CPR

September 10, 2026 by 24 Comments

Usually in Tech In Plain Sight, we talk about technology you probably see every day, even if you don’t notice it. But we hope you don’t get to see one of the latest crop of medical robots, such as the LUCAS chest compression system. If you watch the popular TV series “The Pitt”, though, you may have caught a glimpse of one of these medical marvels. They aren’t fiction. They are very real devices.

Calling them robots might be stretching the definition a little. They don’t roam the halls looking for patients. But once attached to someone in cardiac arrest, they can take over one of the most important — and physically demanding — parts of CPR: chest compressions.

Keep The Blood Moving

When someone’s heart stops pumping blood, time is critical. CPR doesn’t normally restart the heart on its own. Instead, chest compressions produce enough blood flow to keep oxygen reaching the brain and heart while rescuers work on the underlying problem and, when appropriate, use a defibrillator.

Doing that well is harder than it looks on television. Current American Heart Association guidelines call for adult chest compressions 100 to 120 times per minute, at least 5 cm deep but generally no deeper than 6 cm, while allowing the chest to recoil fully between compressions. Interruptions should be kept to a minimum.

That’s hard physical work. In fact, studies show compression depth begins to fall after only about 90 to 120 seconds, which is one reason CPR teams normally swap compressors every two minutes. But a robot doesn’t get tired.

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One Bit Sound With The ZX Spectrum

September 8, 2026 by 12 Comments

[Michael] has a thing for playing audio over beepers using a single bit. He’s done it with the Apple ][ and the IBM PC. This time he turns to the ZX Spectrum. He didn’t get quite as good a result — at least not yet — but he did manage to get some things working. He documents everything, so even though this wasn’t a successful week, there’s sometimes more to learn from reasonable failures than from unreasonable successes.

Of course, the whole thing relies on pulse code or pulse width modulation. Of the two techniques, PWM should produce better results. However, he wasn’t able to get PWM working yet. Some other target computers drive the buzzer through a dedicated hardware timer. However, with the Spectrum, it is all software.

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A 1024 Byte Python Interpreter

September 8, 2026 by 10 Comments

Like many of us, [Austin] finds writing code satisfying — especially if it is challenging. His latest challenge: shoehorn something that looks like Python into 512 bytes. Ok, that didn’t work out, but would you believe 1024 bytes of source code?

The goal was to properly execute a fizzbuzz program using a decidedly Python-like syntax. Since he is only interpreting Python, some things were simplified. In addition, he tried hard to minimize things like whitespace and variable names. Still, there were other things to do, and he borrowed from tips for code golfing.

The resulting code is essentially illegible, but it handles integer variables and literals, assignment, arithmetic, many control structures, functions, and even print. Not bad for 1 K.

Despite being tiny, the parser does a lot, but it does cut corners. No bytecode, no syntax tree, and no error handling. Variables have to be a single lowercase letter. So, ok, it isn’t really Python. But it is something.

Naturally, this reminded us of the obfuscated C code contest. If you really want to go small, we appreciate small Forth.

WordStar Lives Again (and Again)

September 6, 2026 by 30 Comments

Word processors and editors are a funny thing. It doesn’t really matter what’s “best,” whatever that means. If you have finger memory built up for one program, it’s painful to change. That’s why most of us don’t learn how to type on a Dvorak keyboard and why [George R. R. Martin] writes with WordStar. Many people of a certain age have a deep memory of WordStar. Now you can run it on a modern machine or even in your browser without a lot of trouble, thanks to [nampara-ai].

The idea is simple. Take a vintage copy of WordStar for MSDOS, wrap it with DOSBox, and package it up with some basic scripts for Linux, Mac, or Windows. In addition, there’s a WebAssembly version for the browser if you’re into that sort of thing.

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Running Apple ][ Software On A Commodore 64 — Silently

September 5, 2026 by 8 Comments

The computer business in 1984 was a bizarre mix of hobby-level companies, a few small companies that had made it big, and a lot of big companies starting to take notice of personal computers. Plenty of money followed, which led to strange products and even stranger ads. [Such Bad Tech Ads] reveals a very bad ad from that time for a product we have barely heard of: the Spartan. The Spartan’s job was to convert your Commodore 64 so it could run Apple ][ software. The ad campaign had, inexplicably, a mime. We think. Or maybe a clown. Hard to say.

On the face of it, the Spartan might not be a bad idea. In 1984, there was plenty of Apple software. Well, relatively, anyway. But a Commodore computer was far cheaper. Other conversion kits like the Intel Inboard/386 managed to find some success in the market later. The problem, outside of strange ads, was one of timing.

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COSMAC Elf Turns 50

September 4, 2026 by 28 Comments

If you were interested in computers in the early 1970s, you struggled to get time on real computers since owning your own was all but impossible. In the middle of the decade, though, you could get a few computers: the Mark VIII, the Altair, the Apple I, and several others. Those were still pretty expensive, though. But in late 1976, an article in Popular Electronics said you could build a “powerful, expandable” computer for $80. The article in question was by [Joseph Weisbecker], who, unknown to most of us at the time, was actually the RCA employee behind the CPU — an RCA 1802. [Tech Time Traveler] takes a close look at the spunky little computer’s history in the video you can see below.

The 1802 was actually the second generation of the CPU, but the first that was all-in-one chip. [Weisbecker] started building the CPU as a personal project. He’d been a hacker even in high school, building relay-based tic-tac-toe games, among other things.

The first incarnation in his lab was “Fred,” with 100 TTL chips, and his idea was to have the computer be at least partially used as a video game — an interesting point, with Pong being very popular at the time.

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