arm

382 Articles

World’s Cheapest ARM Debugger Is Actually RISC-V

October 22, 2025 by 18 Comments

[bogdanthegeek] has a lot of experience with the ARM platform, and their latest escapade into working with cheap ARM chips recovered from disposable vapes involved a realization that it was just plain wrong to debug such recovered silicon with something as expensive as a Pi Pico. No, they needed to build a debugger using the super cheap CH32V003.

What follows is an interesting tour around ARM Debug Access Port (DAP) programmers and creating a practical USB-connected device that actually works with modern toolchains. The first problem to be solved was that of host connectivity. These days, it’s USB or go home, which immediately limits the microcontrollers you can choose. Luckily for [Bogdan], they were aware of the excellent work by [cnlohr] on wedging low-speed USB support onto the RISC-V CH32v003 with the software-only bit-banging rv003usb, which provided a starting point. The next issue was to check for interrupt-driven endpoint support (needed for low-speed USB) in the Mac OS X kernel, which they knew was being dropped at an alarming rate (well, at least for full-speed). Luckily, the CMSIS-DAP standard required support for interrupt-driven USB endpoints, so kernel support was likely intact.

Next, [Bogdan] noticed that the DAPLink project had been ported to the bigger, native-USB WCH chips like the CH32V203, so it was a matter of porting this code to the diminutive CH32V003 using the rv003usb stack for the USB support using [cnlohr]’s ch32fun toolchain. There were a few bumps along the way with a lack of clarity in the DAPLink code, and some inconsistencies (across platforms) with the USB library dependencies of the upstream tool pyOCD, but they did get some tools working on at least Mac OS and some others on Linux. Which was nice.

We’ve covered the CH32V003 a fair bit, with people trying to give it all kinds of big-CPU tricks, such as speech recognition (of sorts) or even building a supercluster.

Zynq-7000 banner.

Building A Custom Zynq-7000 SoC Development Board From The Ground Up

April 20, 2025 by 8 Comments

In this series of 23 YouTube videos [Rich] puts the AMD Zynq-7000 SoC through its paces by building a development board from the ground up to host it along with its peripherals. The Zynq is part FPGA and part CPU, and while it has been around for a while, we don’t see nearly as many projects about it as we’d like.

[Rich] covers everything from the power system to HDMI, USB, DDR RAM, and everything in between. By the end, he’s able to boot PetaLinux.

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Help Propel The Original ARM OS Into The Future

March 30, 2025 by 33 Comments

We use ARM devices in everything from our microcontroller projects to our laptops, and many of us are aware of the architecture’s humble beginnings in a 1980s Acorn Archimedes computer. ARM processors are not the only survivor from the Archimedes though, its operating system has made it through the decades as well.

RISC OS is a general purpose desktop operating system for ARM platforms that remains useful in 2025, as well as extremely accessible due to a Raspberry Pi port. No software can stand still though, and if RISC OS is to remain relevant it must move with the times. Thus RISC OS Open, the company behind its development, have launched what they call a Moonshots Initiative, moving the OS away from incremental development towards much bolder steps. This is necessary in order for it to support the next generation of ARM architectures.

We like RISC OS here at Hackaday and have kept up to date with its recent developments, but even we as fans can see that it is in part a little dated. From the point of view of RISC OS Open though, they identify support for 64-bit platforms as their highest priority, and to that end they’re looking for developers, funding partners, and community advocates. If that’s you, get in touch with them!

Ask Hackaday: What Would You Do With The World’s Smallest Microcontroller?

March 17, 2025 by 94 Comments

It’s generally pretty easy to spot a microcontroller on a PCB. There are clues aplenty: the more-or-less central location, the nearby crystal oscillator, the maze of supporting passives, and perhaps even an obvious flash chip lurking about. The dead giveaway, though, is all those traces leading to the chip, betraying its primacy in the circuit. As all roads lead to Rome, so it often is with microcontrollers.

It looks like that may be about to change, though, based on Texas Instruments’ recent announcement of a line of incredibly small Arm-based microcontrollers. The video below shows off just how small the MSPM0 line can be, ranging from a relatively gigantic TSSOP-20 case down to an eight-pin BGA package that measures only 1.6 mm by 0.86 mm. That’s essentially the size of an 0603 SMD resistor, a tiny footprint for a 24-MHz Cortex M0+ MCU with 16-kB of flash, 1-kB of SRAM, and a 12-bit ADC. The larger packages obviously have more GPIO brought out to pins, but even the eight-pin versions support six IO lines.

Of course, it’s hard not to write about a specific product without sounding like you’re shilling for the company, but being first to market with an MCU in this size range is certainly newsworthy. We’re sure other manufacturers will follow suit soon enough, but for now, we want to know how you would go about using a microcontroller the size of a resistor. The promo video hints at TI’s target market for these or compact wearables by showing them used in earbuds, but we suspect the Hackaday community will come up with all sorts of creative and fun ways to put these to use — shoutout to [mitxela], whose habit of building impossibly small electronic jewelry might be a good use case for something like this.

There may even be some nefarious use cases for a microcontroller this small. We were skeptical of the story about “spy chips” on PC motherboards, but a microcontroller that can pass for an SMD resistor might change that equation a bit. There’s also the concept of “Oreo construction” that these chips might make a lot easier. A board with a microcontroller embedded within it could be a real security risk, but on the other hand, it could make for some very interesting applications.

What’s your take on this? Can you think of applications where something this small is enabling? Or are microcontrollers that are likely to join the dust motes at the back of your bench after a poorly timed sneeze a bridge too far? Sound off in the comments below.

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USB Stick Hides Large Language Model

February 17, 2025 by 27 Comments

Large language models (LLMs) are all the rage in the generative AI world these days, with the truly large ones like GPT, LLaMA, and others using tens or even hundreds of billions of parameters to churn out their text-based responses. These typically require glacier-melting amounts of computing hardware, but the “large” in “large language models” doesn’t really need to be that big for there to be a functional, useful model. LLMs designed for limited hardware or consumer-grade PCs are available now as well, but [Binh] wanted something even smaller and more portable, so he put an LLM on a USB stick.

This USB stick isn’t just a jump drive with a bit of memory on it, though. Inside the custom 3D printed case is a Raspberry Pi Zero W running llama.cpp, a lightweight, high-performance version of LLaMA. Getting it on this Pi wasn’t straightforward at all, though, as the latest version of llama.cpp is meant for ARMv8 and this particular Pi was running the ARMv6 instruction set. That meant that [Binh] needed to change the source code to remove the optimizations for the more modern ARM machines, but with a week’s worth of effort spent on it he finally got the model on the older Raspberry Pi.

Getting the model to run was just one part of this project. The rest of the build was ensuring that the LLM could run on any computer without drivers and be relatively simple to use. By setting up the USB device as a composite device which presents a filesystem to the host computer, all a user has to do to interact with the LLM is to create an empty text file with a filename, and the LLM will automatically fill the file with generated text. While it’s not blindingly fast, [Binh] believes this is the first plug-and-play USB-based LLM, and we’d have to agree. It’s not the least powerful computer to ever run an LLM, though. That honor goes to this project which is able to cram one on an ESP32.

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The Last Acorn BBC Computer Wasn’t A BBC Micro

December 17, 2024 by 27 Comments

For home computer users, the end of the 1980s was the era of 16-bit computers. The challenge facing manufacturers of 8-bit machines through the middle of the decade was to transfer their range and customers to the new hardware, and the different brands each did this in their own way. Commodore and Atari had 68000-based powerhouses, and Apple had their 16-bit-upgraded IIGS for the middle ground below the Mac, but what about Acorn, makers of the BBC Micro? They had the Archimedes, and [RetroBytes] takes us through how they packaged their 32-bit ARM processor for consumers.

The A3000 was the computer you wanted if you were a geeky British kid at the end of that decade, even if an Amiga or an ST was what you got. Schools had bought a few of the desktop Archimedes’, so if you were lucky you’d got to know Arthur and then RiscOS, so you knew just how fast these things were compared to the competition. The video below the break takes a dive into the decisions behind the design of this first ARM consumer product, and along the way it explains a few things we didn’t know at the time.  We all know what happened to Acorn through the 1990s and we all use ARM processors today, so it’s a fascinating watch. If only an extra two hundred quid had been in the kitty back then and we could have bought one ourselves.

If you have never used an Archimedes you can get pretty close today with another Cambridge-designed and ARM-powered computer. RiscOS never went away, and you can run it on a Raspberry Pi. As we found, it’s still pretty useful.

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A hand holds a small PCB with an edge connector over the exposed, mostly black components of an M4 Mac mini. The bottom cover is hanging by an FFC cable off to the left of the

Upgrading The M4 Mac Mini With More Storage

December 1, 2024 by 17 Comments

Apple’s in-house chips have some impressive specs, but user serviceability is something Apple left behind for consumer machines around a decade ago. Repair legend [dosdude1] shows us how the new M4 Mac mini can get a sizeable storage upgrade without paying the Apple tax.

The Mac mini is Apple’s least expensive machine, and in the old days you could swap a SATA drive for more storage and not pay the exorbitant prices that OEMs demand. Never one to turn down a walled garden, later Intel machines and now the ARM-based M-series chips soldered storage into the machine leaving an upgrade out of the hands of anyone without a hot air station.

Both the Mac Studio and Mac mini now have proprietary storage cards, and after some tinkering, [dosdude1] has successfully upgraded the storage on the base model M4 mini. While most people don’t casually reball NAND chips while chatting on a video, his previous work with others in the space to make a Mac Studio upgrade kit give us hope we’ll soon see economical storage upgrades that keep the Mac mini affordable.

We’ve previously covered the first time Apple tried to make its own processors, and some of their more recent attempts at repairability.

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