PiPedal Grants Guitar Effects, Amp Emulation, And More

November 4, 2026 by Donald Papp 4 Comments

Back in the day, if one wanted a particular guitar effect one would purchase an effects pedal or “stomp box”, and even a modest collection of them could be an eye-watering investment. A guitar amp chosen for a specific sound could be another huge purchase (and who stops at one?) But if you’ve got a Raspberry Pi kicking around and a bit of free time, PiPedal provides configurable effects, guitar amp emulation, and more.

The audio engine runs on a Raspberry Pi, with configuration and control accessed by mobile device or web browser.

Things have come a long way in terms of audio processing, and PiPedal is no straightforward application of simple digital filters. We indirectly learned about it from a fellow who used it to experiment with a range of equipment he could in no reality actually afford. He shared his experience in a blog post that left him thinking he might as well sell all his pedals and build the stomp box of his dreams around PiPedal.

PiPedal’s impressive audio engine runs on a Raspberry Pi (or comparable single-board Linux computer) with control and configuration accessed from a mobile device or web browser. It’s expressly designed to seamlessly work whether one is at home, on stage, or in a studio.

The GitHub repository has code and documentation, so check it out. And if you use it as the basis of a project of your own, don’t keep it to yourself! Drop us a note on the tips line because we absolutely want to know all about it.

Cat Feeder Ensures Fed Cats

November 3, 2026 by Bryan Cockfield 17 Comments

Automatic cat feeders are a dime a dozen, largely because this is an easy problem to solve. Dry cat food is easy for machines to manipulate, and the electronics needed to accomplish the task to a bare minimum are plentiful and inexpensive. But just doling out food is only easy part of the problem. [Jason] wanted to make sure that his cats actually ate once the food was dispensed so he added a few extra features to this cat feeder.

The main addition to this feeder compared to off-the-shelf models is a weight sensor under the bowl. The feeder metes out a certain amount of food, and then a Raspberry Pi Pico W keeps an eye on the weight of the dish. If it goes down, presumably the cat has eaten all of the food. But just to be sure, an ultrasonic sensor was added beside the bowl to ensure something cat-shaped was there at the same time. There was some issue with this sensor blasting out noise in a cat’s audible range at first, but it seems like that problem has since been solved as well.

The build has a few other perks as well. The hardware has wireless communication ability, so it’s easy to keep an eye on when out and about. It can log data and is much more programmable than others. Like most cat feeders, though, it’ll only work for dry food. For automatically feeding wet food something like this robotic feeder that opens cans and dispenses them at set intervals would be needed.

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2026 Retrocomputing Challenge: NEC 286 Laptop Rides Again

October 9, 2026 by Tyler August 6 Comments

The sad reality is that all consumer electronics are going to be e-waste eventually. [Cory Whitesell] was determined his old NEC ProSpeed 286 Laptop wouldn’t meet that fate until absolutely necessary, so when his attempts at repairs failed, his efforts pivoted to create a retro battlestation from the stylish old machine.

That screen looks too good to be stock, but otherwise you can’t tell from this angle.

Externally, it looks pretty well stock, and [Cory] has retained as much of the internals as possible. The original power supply remains intact, with power taken off the original HDD’s molex connector. Said power drives a Raspberry Pi, which is small enough to fit inside without any gutting. The original keyboard connects easily enough via a PS/2 to USB adapter, while the passive-matrix LCD has been replaced with a modern screen of the same dimensions. You’d have to be a pretty hard-core purist to mourn that last change.

With emulation on the Pi, he can still have the DOS experience you’d expect from this machine, but its also powerful enough to be useful in the modern day. While we place no bets on whether or not this mod will stay relevant for another 38 years, a more powerful single-board computer or slightly-squished cell phone can be placed in the drive bay instead once the Pi’s ARM processor inevitably starts to look as anemic as the 286 does now.

Not everyone loves this kind of restomod, but we’ve featured more than a few and have a special category for it in our ongoing retrocomputing contest for those who will do everything to keep classics out of the e-waste bin, including remaking them.

The Least Annoying Of All Evils

September 26, 2026 by Elliot Williams 64 Comments

If you missed the hubbub this week, it was discovered that the Raspberry Pi Foundation added code in the firmware that locks the boot process up if non-original RAM chips are detected onboard. Hot-rodding your Pi is a time-honored tradition in these parts. We do wonder just how many folks are taking the risk of hot-airing the memory off the board, versus paying the extra cash to get one with more RAM. But according to Raspberry Pi, enough boards are showing up that have the RAM surreptitiously replaced, and often defective, that they took the step to lock the machine down.

Should users be alerted to potentially unscrupulous behavior by the companies selling them single-board computers? I think we’d all say “sure”. But should that entirely brick the device? And prevent people from upgrading their own? The hacker in me says “no”. Is there any way to reconcile these two? Our own [Arya Voronova] suggests that it’s no big deal to flash an older version of the initial firmware, and we concur, although it does leave behind all the improvements since 2023, and it will only get less fresh as time goes by.

How to announce that the board has non-factory memory without breaking it? [Jeff Geerling] suggested a non-matching-memory bit that users could check, but then they could also neglect to check. My cellphone has a screen that appears every bootup, and requires me to press the power button to continue, because I rooted the phone and installed an open-source OS. It’s a hassle for sure, but it’s a lot better than bricking the phone or disallowing user firmware entirely.

Doing the same thing for the Raspberry Pi isn’t as easy. You never know what, if any, peripherals are connected, so you can’t guarantee that there’s a screen to alert you or even necessarily a keyboard on which you could acknowledge. We’re reminded of a similar situation with FTDI USB-to-serial converter chips ages ago. Their driver software simply refused to work with counterfeit versions of their chips. Hackers were up in arms, largely because we couldn’t know if the parts were genuine at purchase time, and the counterfeits were widely distributed even by reliable resellers.

So what about it? Can you think up a tamper-evident signal that could run on boot on a Raspberry Pi, maybe a headless system installed in some difficult-to-reach place? Maybe ideally the equivalent of the cell phone’s scare message? It would have to be hard to overlook, but keep the machine running, notifying the user that things aren’t kosher, but not preventing them from getting to work. Sounds like a tall order to us.

Solar Powered Traffic Monitoring

September 24, 2026 by Zoe Skyforest 8 Comments

[Marios Christoforou] recently undertook a Computer Engineering degree at the University of Cyprus. His final year project involved implementing a solar-powered device to count vehicular traffic, while logging results to the cloud.

The project is built around a Raspberry Pi 5, specifically the version with 4 GB of RAM. It runs Raspberry Pi OS and is equipped with a basic webcam with 720p video output. The single-board computer runs off a 12 volt lead acid battery, which is charged via a 100 W solar panel hooked up to a basic charger module. Identifying vehicles in traffic is achieved with the YOLOv8 Nano machine vision model, which outputs bounding boxes around cars, trucks, buses, and motorcycles captured in the webcam feed. Software algorithms are used to ensure vehicles are only counted once as they pass through the camera’s field of view.

There’s plenty of detail on how the project was refined to meet initial goals. To make the most of the solar power available, [Marios] optimized the setup with an eye to performance and low power draw. To that end, the Raspberry Pi had Bluetooth, the PCIe slot, audio, and HDMI ports all disabled, while the CPU and GPU were both under-clocked for good measure. Software tweaks were also used, like running headless and dropping unimportant parts of the video frame for more efficiency.

We’ve featured other homebrew traffic monitors before. These days, though, it’s Flock cameras that seem to be making all the headlines in this area.

Raspberry Pi RAM Restrictions No Big Deal, Frankly

September 22, 2026 by Arya Voronova 167 Comments

Hacking on Raspberry Pi board internals is one of my favourite topics. I know a bunch of obscure things about these cute little boards. Three years ago, I covered a Raspberry Pi 4 RAM upgrade story. Getting a BGA RAM chip and swapping it in seemed like a no-brainer to me – apart from all the numerous uncertain parts about it, you know. It was a joy to see hackers pull it off, and for it to function as well as it did!

Things changed. You can’t really get RAM chips anymore. You also can’t get RAM sticks. You can’t get even SSDs with RAM chips on them. Even getting Raspberry Pi boards can be hard unless you know where to look. This is where a recent three-minute video by [Jeff Geerling] finds us.

Turns out, Raspberry Pi Foundation pushed binary-blob bootloader changes that limit your ability to upgrade RAM. I’ve known about it since last year through the grapevine, and somehow, as I read about it, this didn’t bother me at all. Not enough to write a Hackaday article about it, even, much less talk about it more widely. Why didn’t it bother me? Today, I sat down and pondered this for a bit.

Here’s my conclusion: I don’t think it’s a big deal at all, even if it seems that many people would disagree. Come in, as you are, and I hope you find my thoughts on the situation entertaining.

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Raspberry Pi Locks Down RAM Upgrades

September 22, 2026 by Maya Posch 66 Comments

In a recent video [Jeff Geerling] addresses an issue discovered with the Raspberry Pi firmware, specifically how since around 2024 the firmware locks down what RAM size and even module is supported. This isn’t an issue that is widely known, probably because most people just use the board as-is, but it can be an unpleasant surprise for those looking to upgrade or repair their Pi.

Naturally there is a valid reason for wanting to prevent unscrupulous RAM module changes, with a [Geekworm] blog post from earlier this year detailing this exact issue and how each board is marked with a specific code that identifies the model, RAM size, RAM manufacturer and such. Based on the earlier linked forum post and also a 2025-era GitHub ticket on the rpi-eeprom project, the resulting symptoms seem to vary from not seeing the additional RAM to the board not booting at all.

Although you can go back to an older EEPROM firmware image to work around this, it’s still very annoying that this is even a thing. As also noted by [Jeff], the primary frustration here is probably one of ownership. When you can upgrade the RAM on just about any device you can buy, including a modern GPU and even Apple computer, but not on a Raspberry Pi board that loves to flaunt its open source/hardware credentials, then something is very much off.

In the end it’s highly unfortunate that Raspberry Pi has chosen this path that feels a bit too much like the hardware pairing that companies like Apple got rightfully called out on.

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