The Bootloader

Episode 32 - Wave of Mutilation

Mon, 04 May 2026 00:00:00 +0000

Welcome to the show

Published: May 4th, 2026

In this episode, Tod and Paul discuss adding textures to your 3D prints, an open source music player, a new cross-platform serial plotter, and more.

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Full transcript available here.

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Show Notes

00:20 Open BoardsGuide (Paul #1)

Open Boards Guide is a brand new website from David Groom (aka "ishotjr") focused on news, reviews, and project highlights on embedded development boards.

4:49 BumpMesh.com (Tod #1)

BumpMesh.com is a web-based tool to let you add arbitrary textures to your 3d printable models. Just import an STL, pick a texture or upload your own, adjust the texture's settings, and export your modified STL. It's free. Runs in your browser, no service, no login, no privacy issues. If you've ever used the "Fuzzy Texture" option when printing a 3d model to get a more interesting surface to your models, you'll definitely want to try this out. It's really cool!

BumpMesh is created by Stefan from the Youtube channel CNCKitchen. He wanted something more interesting that just fuzzy skin. He recognized that in 3d computer graphics, the displacement maps or "bump maps" that simulate bumps and wrinkles are just black-and-white images, where pixel brightness corresponds to "height" above the normal level of a surface. And that those bump maps could actually perturb the surface of a 3d model. You can turn simulated bumps and creases into actual ones! And there are tons of existing bump map textures available to try out. Also, a bump map is just a black-n-white image, you can easily make your own.

In BumpMesh once you pick a texture map, you can adjust many parameters of it so it wraps around your model in a way that makes sense. For instance, if you've picked a "brick wall" texture, you may not want it on the top & bottom of your model, and you may want to adjust how the texture lines up on the edges. There's a built-in 3d visualizer so you can see your changes in real time. It's tons of fun to try out different textures on even simple shapes like spheres and cubes.

Highly recommended as a way of adding detail to your 3d shapes without having to model that detail in CAD.

8:10 Parachord Music Player (Paul #2)

Parachord is a music library app written using Electron and runs on Windows, Mac, and Linux. Parachord is open source, licensed under the liberal MIT license. What makes it unique is that it's a multi-source music player, meaning you can connect your Spotify or Apple Music libraries to it, as well as local music, Bandcamp, and YouTube.

11:51 SerialPlotster (Tod #2)

Time for some shameless self-promotion. I "wrote" an cross-platofrm app for Mac, Windows, and Linux called SerialPlotster. It's a data graphing app for use with Arduino, MicroPython, CircuitPython, and similar boards. If your project spits out data, this app can graph it. It's a very tiny download at ~10 MB and launches fast.

Back in 2015, one of the best additions to the Arduino IDE was added: the Serial Plotter. Just a print a value in your Arduino sketch and you could see a cool plot of it. Add more values and now you have a multi-series real-time plot of those values against each other. The obvious use is data-logging but I find it really helpful for debugging. Being able to see how a value changes graphically hits different than just watching scrolling numbers.

As I started doing CircuitPython & Micropython stuff, I lost the plotter. I tried the Arduino plotter but it's too "helpful" in grabbing the serial port, making connecting back to the REPL frustrating. Or try the Mu editor's nice plotter, but it's also port grabby. The Thonny editor got a plotter in 2019, inspired by Mu, but I just don't like Thonny for reasons I've not inspected.

So clearly plotters ae a useful thing, as all these IDEs had them. I want to use my own choice of editor and I don't really want a huge IDE that may or may not have a plotter extension. So every once in a while I'd go looking for plotter apps. There are a few, but they're either weird, abandoned, or web-based.

One really great web-based one is called Web Serial Plotter by atomic14. If you run a Chromium-based browser that supports WebSerial and like web apps, it's a great solution. No need to look further.

I wanted an actual application on my desktops, both Mac and Linux. I've built many of these in the past. My normal tool of choice is Electron, which as you may know, let's you write Javascript to make a desktop app. This is great but means the app ends up being over 200 MB in size because it's actually just Chromium wearing your app's clothes. It's also slow to launch and takes up a lot of RAM. I always feel kinda gross writing in Electron.

The alternative I've been playing with lately is called Tauri, which uses Rust for the OS-specific stuff and the OS's built-in web renderer for your app's GUI. If you're experienced with making web apps, 90% of your skills and process stay the same. But if you can figure out that 10% that's Rust, you're rewarded with an app that's literally 20 times smaller and has a tiny RAM and CPU usage footprint.

But I don't know Rust. I know just enough to know I don't know anything. I banged on adapting the concepts of web-serial-plotter to Tauri and got it sorta working but was running up against my lack of knowledge and my lack of modern web development skills. So I brought in Claude Code and asked it figure out what I was doing wrong. It was quite helpful! It rewrote huge swaths of my code, most all of my Rust, and cleaned up how I was using my React objects in the GUI. And then, most importantly, it helped me write a huge barrage of tests for the data parser in Rust. Now that I can have tests written for me, I've been much more of a fan of projects having a test suite.

So anyway, thanks atomic14 for Web Serial Plotter. It looks like you also used Claude to help you write it and released it under GPL3. SerialPlotster is also on GPL3 and you can download pre-built and signed binaries for MacOS, Windows, and Linux. If you like it, let me know! If you have any suggestions for improvements or fixes, also let me know!

18:19 picoCAD 2 (Paul #3)

picoCAD 2 is a 3D modeling tool lets you make low poly models. As its description says, it's meant to be "a fun, easy, and accessible 3D modeller focusing on the bare essentials". You can create retro-style models using its built-in texture editor and you can animate your models and export them to GIFs. You can also export them in OBJ/MTL or GLTF and import them into modern game engines to create your own game assets, as well as being able to export the sprite sheets.

It's available for $14.95 on Steam or itch.io.

21:13 WaveOverhangs (Tod #3)

There's some new research in 3D printer model slicing that just came to my attention called [WaveOverhangs]((https://waveoverhangs.com). It lets you print steep overhangs without supports. 3D printer toolpaths are generated recursively based on wave‑propagation theory, instead of the standard layer stacking used today. This is a big change to how we normally think of 3d printing and if it ends up being actually useful, could cause 3D printers to be designed differently. You can try it right now with a custom fork of OrcaSlicer that has WaveOverhangs built in.

The process of turning a 3d model into instructions for a 3D printer is called "slicing" because traditionally the process divides the model into a series of horizontal layers and the 3d printer prints out those layers, stacking them up on top of each other. Steep overhangs present a problem because there's now part of alayer that's just floating in space without anything holding it up. If you try to print this, you'll get a messed up print. So slicer software will print disposable supports to hold up these parts. Getting off the supports can be tricky and the surface finish of those overhangs is always worse than other parts of the print.

This "3D object to 2D layer stack" process has meant that most all printers are designed to be fast in the XY part of the printer and slow in the Z dimension, as that just moves to the next layer. The WaveOverhangs process makes slicing a truly 3d operation. The exterior of the model becomes sort of a "wavefront" that ripples into the model, until it meets another wavefront. To fill the shape, recursive wavefronts spawn from the cusp of where two waves meet. It's extremely clever but this means your 3D printer's Z-axis will be working as hard as its XY axes! The task of laying down plastic is no longer putting down stacks of layers but these complicated "blooms" of moves in 3D. The plastic sort of blossoms out to create the overhang, so there's never any fully unsupported plastic.

I've not tried this with an actual 3D printer yet, as I just discovered this. But I have downloaded the WaveOverhangs fork of OrcaSlicer and have sliced a few simple models with it. It's really interesting to look at the resulting toolpaths! One of the main issues I can imagine will be a problem is warping. As the plastic cools it shrinks along the direction of its extrusion. With these wave-like shapes that produce the overhanges, there's a lot of extruded plastic "pulling up" on that overhang. Some of the example prints on WaveOverhangs.com you can see this warping happen. But I'm sure there will be techniques to address this soon.

2026-05-032026-05-03

Episode 31 - Help I'm Alive

Mon, 06 Apr 2026 00:00:00 +0000

Welcome to the show

Published: April 6, 2026

In this episode, Tod and Paul share a secondary display for your Bambu Labs 3D printer, a small eink eReader, an open source microcontroller, and more.

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Show Notes

00:15 BambuHelper (Tod #1)

BambuHelper is a tiny ESP32-powered desk friend to tell you how your 3d printer is doing! It uses MQTT (either LAN mode or Cloud mode) to get your Bambu Labs' printer stats. It shows percent progress, ETA when the print will finish, temps of bed, nozzle, and chamber, and even what type of filament its using.

I finally got a Bambu Labs printer a few weeks ago. The same week, a member of the "/r/esp32" subreddit posted about using an ESP32-S3 "SuperMini" board and a 1.5" square TFT LCD display to pull data from their Bambu P1S printer over MQTT. The build was pretty slick and I bookmarked it to consider later, thinking maybe it would work for my H2 printer. A few days later they posted an update: Surprise, BambuHelper now works for all Bambu printers and it can work either in LAN mode, talking directly to the printer, or in cloud mode where it talks to Bambu's servers over secure TLS MQTT. It's even got a web interface to configure settings and what information to be displayed. And becomes a clock if nothing is being printed.

The build is simple: just eight wires to solder between the ESP32 and display. There's an optional touch button you can wire up, but I don't think it's needed. They also designed a nice 3d-printed. It's got a nice minimal aesthetic, almost retro computer inspired, and is thoughtfully designed by assuming your board already has the header pins soldered. Perfect if, like me, you start out prototyping on a breadboard and then want to use the same hardware for the finished project.

I've got a breadboard build running right now and it's pretty useful. While you can get all this information from the "BambuHandy" app on your phone, I am a big fan of ambient displays. This is going in the house so I can tell at a glance what the printer in my workshop is doing. I'm thinking of making an alternate case that's wall mounted to go on a corkboard.

An outstanding question for me about BambuHelper is: how does it deal with error or warning conditions? Jammed filament, open chamber door, etc. I've not tested that yet, and I come from more than a decade of 3d printing, so I'm used to printers failing as much as them working.

And while I've been pondering all this, our Paul here writes two incredible CircuitPython tools: CircuitBambu, a CircuitPython take on BambuHelper, and more generally a bambulabs CircuitPython library for anyone to get info and interact with a Bambulabs printer in CircuitPython. Super neat and I can't wait to play with it. I'm honestly more interested in modding CircutBambu to work with my one of my "favorite ESP32 dev boards" mentioned in previous episodes, since they have built-in displays. No wiring needed! Thanks Paul, I can't wait to try out your code.2

BambuHelper Links

5:56 OpenScan (Paul #1)

OpenScan is a low-cost and high quality 3D scanner that you build yourself that is open source and modular.

8:53 Xteink X4 eink ebook reader (Tod #2)

Back in February I saw some folks on Blueksy who had a tiny eink book ereader that could magnet to the back of your phone. It was exceedingly simple, having only four buttons, no touchscreen, and explicitly just rendered epub-formatted books you loaded via a micro SD card. I've wanted to try a proper ereader for a while but didn't want to get sidetracked by (or pay the expense of, or pay Amazon for) something like a Kindle. This little $60 Xteink X4 looked like a great choice. And then I learned it had an ESP32 in it!

So I get it, start using it as intended. It's neat! I like the very focussed use case it presents. I think it might be too small for me as a regular ereader. But then I distracted myself from it's original use and started hacking on it. Turns out you can treat it like any other ESP32 dev board. For the record, it's an ESP32-C3 board with 16 MB of flash. Pretty low-end as far as ESP32 devies go. It doesn't have native USB support, just USB serial, but it does have a RISC-V processor and WiFi and Bluetooth.

And then I discover Crosspoint Reader, an entirely open source firmware for the Xteink, written from the ground up. Essentially written in Arduino using platformio, it uses the open source "open-x4-sdk" library to access the various peripherals of the reader in a nice clean way. Crosspoint offers some really neat features like saving your reading position, epubs with images, nicer fonts, WiFi book upload, and over-the-air (OTA) firmware updates. New features are being added all the time so don't wait for a release, just install from github.

And then on top of that, I learn that last month friend-of-the-show Liz, aka BlitzCityDIY, has also been hacking on the X4 and has added a CircuitPython build for it! And she made a nice helper library for it. While the CircuitPython firmware sets up the ePaper display to act as a standard CircuitPython displayio display, the helper library gives you easy access to the battery monitor and buttons (which are implemented as a resistor ladder, so kinda tricky to read). Thanks Liz!

Suffice it to say, there are ton of fun hacking opportunities to be had with this quite well-built little eink ereader. It's sturdy enough to live in my backpack and the fact it can act as an ESP32 WiFi devboard when I need one, gives it double utility. Highly recommended if you want a fun thing to hack on. But as I've not used it much as an actual ebook reader, I can't speak much to that yet!

Links about the Xteink X4

12:58 Project Aura (Paul #2)

We've covered a couple Air Quality monitors over the years, and Project Aura is another, with a small twist. Project Aura is running as a MakerWorld crowdfunding project where you pay $30 for the 3D model, which gets you the 3MF file, firmware, and STL. The bill of materials is also provided, and you have to buy the parts yourself, which are about $200.

The firmware uses Arduino and PlatformIO and LVGL for the graphics - it looks really impressive, check it out with links in the show notes. It even has a night mode.

It also features an integrated web dashboard with live stats, events, settings sync, and OTA firmware updates. Initial setup can be done as it will create a wifi hotspot and uses mDNS to connect to it. And of course, it’s Home Assistant capable and uses MQTT for communication. Lastly, it features a safe boot - it will automatically rollback to the last known good config after crashes, making it easy to use.

17:06 Baochip-1x open source microcontroller (Tod #3)

The Baochip-1x by Bunnie Huang is another microcontroller platform like the RP2040 or the ESP32, but unlike those chips, everything about the Baochip is open source. It's based on open source RISC-V cores and the entire design is open. The Baochip includes a main CPU running at 350 MHz, four smaller cores running at 700 MHz, and a complete suite of accelerators of cryptography and encryption. For memory, it's got 2 MB of RAM and built-in 4 MB of RRAM, which is like flash. And it has an MMU, so it could host real OSes! In size and cost, it's similar to a Raspberry Pi Pico, but it's also so very different.

Bunnie has taken the openness of the Baochip to the max: in addition to the design being open and the ROM bootloader being open, the chip itself is transparent to infrared light, so you can inspect it with a microscope that the silicon you receive is what was promised. It's like a physical checksum to guarantee that the chip's not got malware or comporomized encryption hardware in it.

Recently Bunnie has published a couple of posts on the CrowdSupply campaign page that goes deep into the design details of the chip, comparisons with other chips and designs. As someone who once thought they were going to be a VLSI designer, these posts are magical. I recommend anyone interested in chip design to read them, as they cover decades of CPU design in a few pages.

The Baochip has four BIO I/O co-processors, that are sort of equivalent to the very cool PIO I/O co-processors in the RP2040/RP2350. In a BIO analysis document, Bunnie describes that while the RP2040's PIOs are conceptually simple, they're really quite complex, comparable to older CISC-style processors in how much can be done with a single instruction. This makes PIO take up a lot of physical space on the chip, so Bunnie took a different approach with the BIO processors: make each one a tiny RISC-V processor running at 700 MHz with a few tricks to make them better for I/O tasks. Since the I/O processors are full RISC computers with much more program space than the 32 instructions of PIO, these BIO co-processors could do additional signal processing tasks.

Disclosure: I'm an aquaintance of Bunnie and have personally backed the Baochip crowdfunding campaign. I can't wait to get my hands on these devboards and play around with the Baochip. A fully open chip that's not patent encumbered is the future. We all talk about open source, but everything we base our open designs on ultimately runs on physical chips that are literal black boxes. Let's change that.

Links about the Baochip

21:51 OpenCode (Paul #3)

OpenCode is a 100% open source AI coding agent licensed under the liberal MIT license. It's built for privacy and does not store any of your data. OpenCode comes with a number of free models you can use or you can connect it to most other AI providers, like Gemini, Claude, and GPT.

OpenCode is available in the terminal or there is an app for your desktop and the web.

2026-04-032026-04-03

Episode 30 - Spin the Black Circle

Mon, 02 Mar 2026 00:00:00 +0000

Welcome to the show

Published: March 2, 2026

Tod and Paul chat about an open source record player, a new operating system for MicroPython, you won't believe who's going to Eurovision, and more.

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Show Notes

00:19 Statimatic STM-01 Automatic Turntable (Paul #1)

Patrick Nelson started this project about 4 years ago and then got stuck - but now he’s back and he’s documenting all of his progress to build an open source turntable.

His project goals included:

Only 7” records at 33 1/3 rpm or 45 rpm
Full sized LP expansion
Expansion port
Record changer
Alarm clock
Remote control from a Commodore 64
Automatic capabilities - the tonearm plays and stops on its own
Easily sourced or made parts
Open source design and PCB files
Anti-skate, speed control, track lightly
Treat records nicely

From there, Patrick shares additional videos on the design, how he redesigned the tonearm and another video for its lift mechanism, and more.

5:00 MicroPythonOS and WaveShare ESP32-S3-Touch-LCD-2 (Tod #1)

My new favorite WiFi dev board is the ESP32-S3-Touch-LCD-2 by Waveshare. And it runs this fun new "OS" called MicroPythonOS.

The ESP32-S3-Touch-LED-2 (what a mouthful) is about the size of a candy bar, has a 2" 320x240 captouch screen bonded on top of an ESP32-S3 devboard with 8MB PSRAM, 16MB flash, an SD card reader and a 5MP camera. It's also got an onboard accelerometer and lithium battery management. All for $22. It comes with header pins so you can plug it into a breadboard (but you can't have the camera plugged in while it's on a breadboard, unless you have it straddling two breadbards) I think most uses will see the module placed into a (3d printed) enclosure and used without much extra hooked up to it.

Unlike one of my previous favorite ESP32 boards, this one's display is only via SPI, not parallel bus, so you can't do those blistering fast animations, but it's servicable. Also, the display and SD card share the same SPI bus, so I don't think you'll be recording much video with the camera, but it's great for timelapse or stills.

And there's a basic CircuitPython firmware for it! It just sets up the display, not any of the other peripherals (including the touchscreen), but there is a separately downloadable touch library that works.

But what's really neat about this particular Waveshare module is that it's the main target platform for MicroPythonOS. MicroPythonOS is attempting to provide an Android-like experience for ESP32-sized devices that have touchscreens: a complete UI system with touch gestures, an app store, over-the-air (OTA) updates, and a set of APIs like BatteryManager, AppManager, InputManager, and so on, to make writing apps in MicroPython pretty nice.

When I first started following MicroPythonOS a month ago, it only supported this board, but now it fully supports six different boards with six more coming soon. Two of these coming soon devices are smartwatch style ESP32-S3 gizmos from Lilygo. Very cool that we'll have a full MicroPythonOS smartwatch soon!

Links:

10:16 3D Printing News Roundup (Paul #2)

Tool Trace AI is a site that allows you to upload a picture of your tools and it will create foam shadowboxes or Gridfinity inserts you can 3D print to hold your tools.
3D printing uses AI to fix prints in real time - using multiple LLMs, researchers have created a way for AI to monitor, correct, and fix your 3D prints in real time.
Creality Filament maker - Creality has introduced a filament shredder for your old filament and a filament maker to use from the shredded filament. It can create up to 1 kilo of filament per hour.

14:37 Teenage Engineering Ting EP-2350 (Micropython-based product) (Tod #2)

The clever folks at Teenage Engineering have released an interesting little musical microphone toy. And it's the first commercial product for normies I've seen that is running MicroPython under the hood, and lets you get at the MicroPython it runs. It's called the Ting EP-2350.

The Ting EP-2350 costs about $60 and looks like the handset of a CB radio. But it's got three extra buttons on the side in addition to the talk switch. You plug its curly cable into your mixer or audio input and when you press the talk switch, your voice can be altered by four different audio effects, selected with one of those extra buttons. Four small LEDs tell you which of the four audio effects you've selected. Another button lets you trigger four different sound samples, which can also be effected. The position of the talk handle and shaking the unit can change how the effect alters your sound. Again, another four small LEDs show which sample is currently ready to be triggered.

The list of audio effects is pretty extensive: echo delay with adjustable EQ, feedback, & wet level; distortion with gain & EQ, harmonizer for repitching, reverb with EQ & spring emulation, ring-modulation, and single-side-band (SSB) for that sci-fi/ham-radio squawky audio sound. If you notice, the list of sound effects and their parameters are greater than the number of slots available. How do you reconcile this?

If you plug the Ting into your computer, it shows up like a thumbdrive (just like CircuitPython) and you can edit a "config.json" file that specifies which effect should be in which slot, how its settings should be, and how the handle and shaking inputs should map to those settings. Oh and you can also chain effects! So for a single slot you can feed the EQ into the delay, then into the harmonizer, and then into the reverb. So it's sort of like a virtual guitar pedalboard in a little microphone. Pretty cool!

With the Ting plugged into your computer, you can also connect to its MicroPython REPL and see the code it's running. You'll see that they've created a custom build of MicroPython (version ????) that has a handful of custom built-in modules like fx that manages the audio effects chains, ui to manage the LEDs, accelerometer, and buttons, and spl to handle loading samples and triggering them to play. The entirety of the main.py is just taking that "config.json" file and setting up these modules, there's not much logic in them, as you just configure the fx module to use the shake from ui to adjust a parameter, rather than having Python code do it. But it's really incredible that Teenage Engineering gives this amount of control.

If you've played around with CircuitPython, the ability to chain audio effects is very similar to what we've been able to do for the last year with the built-in audioeffects module. And the type of effects CirPy has is very similar too. The CircuitPython approach is more configurable and exposes much more of the ability to drive the effects in creative ways than what the Ting can do. It's sort of like, the Ting's effects are a small guitar pedalboard but CircuitPython's audioeffects are an entire modular synthesizer acting like a guitar pedal board.

As you might've noticed by the name, the Ting EP-2350 is running an RP-2350 under the hood. I've taken my Ting apart and verified it's got a 2MB flash (leaving 1MB for samples) and shows up almost as a standard RP2350 UF2 boot device. I've not checked yet, but I think they've used some of the new RP2350's security features to only allow signed firmware because a vanilla Pico2 CircuitPython image did not work.

Links:

20:48 Game Controllers (Paul #3)

The OpenSplitDeck is a home built gamepad controller inspired by Valve's Steam Controller. It features two trackpads, joysticks, and more and can also split into two halves to make it more ergonomic. Linus Tech Tips YouTube video
Joypad OS (Adafruit coverage) allows you to build a dongle to connect your game controller to other platforms. The dongle is powered by the rp2040 and you can buy a dev kit for $50 at Joypad.AI.

24:46 LOOKMUMNOCOMPUTER is going to Eurovision 2026 (Tod #3)

My favorite nutty synth professor Sam Bartle, aka LOOKMUMNOCOMPUTER on Youtube, is the UK's surprise entry for Eurovision 2026. Eurovision is a yearly bonkers musical contest and Sam's particular flavor of insanity will fit right in. His performances on his homemade animatronic synths are incredible in their wackyness and his deep musicality. I hope he wins.

I've been following Sam's Youtube channel for about 9 years. He originally hooked me by showing simple synth circuits he turns into proper modules for his homemade modular rig. One of the best for me was the "Simplest DIY Audio Oscillator" that uses a single transistor, capacitor, resistor and LED to make a nice sounding square wave oscillator that's suprisingly musical. For less than $10 he made a 5-voice drone synth that sounds amazing. His online delivery is almost the exact opposite to previously-mentioned Moritz Klein's very calm and considered synth design approach. Every circuit Sam makes as he hand-drills the panels, Sharpies knob labels, and solders over live circuits makes you almost expect a disaster to happen. But it never does. Sam is a professional and exceedingly fun to watch.

Other great videos of his are his Furby Organ where he takes 45 Furbies and hacks them into a nice wood-enclosed organ. Or the 1000 oscillator megadrone that takes that simple oscillator circuit and multiplies it by literally a thousand. The final result takes up a whole wall. He's built a tonne of other gear and he his builds are explicitly for him to perform with because he's also a professional musician, often on tour

With all these huge builds though, Sam needed a place to put them all. So he created This Museum is Not Obsolete, a real physical museum of experimental and old technology in Kent, UK. You can go there an play on some of this gear. And see other amazing artifacts like old test gear and ancient telephone switching equipment, all of it hooked up and able to make cool noises.

Links:

2026-02-282026-03-31

Episode 29 - Kick Out the Jams

Mon, 02 Feb 2026 00:00:00 +0000

Welcome to the show

Published: February 2, 2026

In this episode, Tod and Paul discuss hacking Flock cameras, the Adafruit Fruit Jam, Neural Networks in CircuitPython, some bad 3D printing legislation, and more.

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Full transcript available here.

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Show Notes

Flock camera hacking w/ Benn Jordan (Tod #1)

Links:

Naya Connect Modular Keyboard Kickstarter (Paul #1)

The Naya Connect is the second product launch from Naya, who has a Kickstarter campaign for their new modular keyboard, the Naya Connect. They previously launched their split keyboard also on Kickstarter.

The Naya Connect features a low profile keyboard that's ultra thin at just under 15mm. But what's innovative about it is that it's modular, allowing users to customize their keyboard layout and functionality. You can choose from different expansion modules including:

Multipad - a 4x4 Macropad that can work as a number pad or anything you program it for.
An extra column of 6 keys, laid out vertically.
4 different input modules to let you replace your mouse, including a trackball, touchpad, a dial and a floating joystick.

And what's really neat about all of these modules is they're made for both right and left-handed users with connections for reach module on either side.

It also includes Naya Flow, their custom software that allows you to program your keyboard layout and all of the modules.

If you're quick, you can jump on the Kickstarter as it has about a week left from when this episode is being released. Options start at about $180 and quickly go up from there depending on what modules you choose.

ESP32-C5 now in Xiao form (Tod #2)

ESP32 finally supports 5 GHz!

ESP32 chips and dev boards are currently the best way to do WiFi with microcontrollers, in my opinion. They're fast, have lots of memory, and rich built-in peripherals for driving displays, audio I/O, etc. And you can program them using the vendor supplied ESP-IDF SDK, Arduino, Micropython/CircuitPython, or even the super modern languages like Rust and Swift.

But the term "ESP32" is kind of misleading. It's not a description of a chip architecture, but more like a brand, more akin to the term "make" in cars. There are multiple chip architectures in the ESP32 family, with the more modern being RISC-V-based ones. It used to be saying "ESP32" by default meant "WiFi microcontroller" but now even that's now true, with the new ESP32-P4 chip that does not have WiFi (it has a lot of GPIO and seems to be good at driving bigger displays)

The problem with all the different variations of the ESP32 WiFi chips though has been they're all on 2.4 GHz WiFi. Even the very recent ESP32-C6 chip that boasts WiFi 6 support, only does that on 2.4 GHz. The 2.4 GHz frequency spectrum is the original that WiFi is on and is still great for longer distance, but 5 GHz is the norm in most home and office setups. To the point that some WiFi access points encourage you to turn off the 2.4 GHz side of things!

But there's now dev boards available using the ESP32-C5 chip. This is a dual-band WiFi 6 ESP32 that does both 2.4 GHz and 5 GHz. While both Espressif (maker of the ESP32) and Waveshare have had larger dev boards with the ESP32-C5, just recently Seeed is now selling a Xiao board using the ESP32-C5. This is great! If you already have a WiFi project using a QTPy or Xiao board, you may be able to just swap it out for the new ESP32-C5 Xiao and get your project on 5 GHz.

Oh and another cool thing about the ESP32-C5 is that it can support Matter and Thread protocols too. I suspect we'll be seeing this chip in a lot of home automation projects in the future.

Links:

Let's chat about the Adafruit Fruit Jam (Paul #2)

The Adafruit Fruit Jam was first released at the end of July in 2025 and went out to thousands of Adabox subscribers last November. If you haven't heard of the Fruit Jam, it's Adafruit's take on building a mini-computer using the rp2350b microcontroller. With all the extra GPIO in the rp2350b, Adafruit was able to add DVI out using an HDMI port, 2 USB ports for USB host to hook up gamepads, mice, and keyboards, a microSD card slot, and a StemmaQT port to add additional sensors.

Not only is the product innovative, I'm blown away by the community's response and all the cool software that is available to run on the Fruit Jam.

Adafruit Fruit Jam Hardware
Fruit Jam OS
Fruit Jam OS includes a number of apps and games, including Breakout, an IRC client, Minesweeper, PyPaint, and more.
Retrojam
Fruitris, a Tetris clone by Cooper Dalrymple
Pac-Wio
- Zork and the Z Machine by Dan Cogliano
Paul’s interview with Dan on The CircuitPython Show
Moon Miner Learn Guide
Fruit Jam Mac emulator
Apple II emulator
Intel 286 emulator

Using Native TensorFlow & PyTorch Neural Networks in CircuitPython (Tod #3)

A few weeks ago I came across an interesting blog post by Ashish Patil on how to embed native code versions of trained TensorFlow or PyTorch models into CircuitPython. If you're interested in machine learning or embedding native code into CircuitPython, it's a really useful read.

TensorFlow and PyTorch are both Python-based machine learning tools for building neural networks and other learning models. Normally these run on "real" computers, but we've seen TensorFlow models being run on embedded dev boards for several years now. (In fact, Adafruit made an "Edge Badge" version of their PyGamer board that could do TensorFlow-based voice recognition using TensorFlow Lite in Arduino)

These models are trained on a large fast computer and the resulting models exist as a blob of generated code with essentially a single function that takes an input and returns a result. This code is small enough to run on microcontrollers so there are several mechanisms to stick them into your Arduino code or whatever. But getting them into CircuitPython has been tricky. You can generate a pure-Python version of the model (and Ashish shows how to do this), but that runs pretty slowly.

Ashish's post gives a step-by-step process staring with training the model and converting the result to C with onnx2c tool. (ONNX or Open Neural Network Exchange is a standard way to represent machine learning models). This resulting C-code has no CircuitPython-specific code in it, so his next step of showing how to add this C code to CircuitPython is very clean and understandable.

There are several little niggly changes you need to make to the CircuitPython source tree to add new native code (it's frustratingly more than just sticking it your board's definition directory), but Ashish shows exactly all the files you need to change, so even if you're not interested in machine learning but are interested in adding native code to CircuitPython, this post is helpful.

Washington State's proposed 3D printing bills (Paul #3)

Washington State representative Osman Salahuddin has proposed two bills:

HB 2320 adds criminal liability around digital firearm manufacturing code and classifies the machines that make these parts as part of firearms law.

HB2321 requires any 3D printer sold or transferred in Washington after July 1st 2027 to include mandatory DRM that has blocking features that can detect a firearms blueprint. As Adafruit shared: “Printers would have to examine every file, compare it against a centrally maintained list of prohibited designs, reject flagged jobs, and be engineered to resist bypass by “users with significant technical skill.”

This is definitely something to keep an eye on, because if one state is thinking about it, I bet others will be too.

The language as it is proposed is too broad, and I’ll leave you with this quote from the Adafruit blog post:

“None of these controls stop “determined actors”. What they do is burden lawful users, destroy open-source innovation, and force proprietary stacks and cloud services, not safety.”

Wrap-up

Pau lives in the suburbs of Minneapolis, MN which is currently occupied by ICE. To help those on the ground in Minnesota, please visit StandWithMinnesota.com

2026-02-012026-02-01

Episode 28 - Games Without Frontiers

Mon, 05 Jan 2026 00:00:00 +0000

Welcome to the show

Published: January 5, 2026

In this episode, Tod and Paul discuss building your own Steam Machine with Bazzite, learning to sew, building analog circuits using synths, and more. Paul apologizes for his microphone issues and technical difficulties during the recording.

Follow the show on Mastodon or Bluesky.

We have stickers! Request a free sticker here. (US Only, sorry!)

Full transcript available here.

Listen to the podcast

Show Notes

Building my own Steam Machine (Paul #1)

Back in mid-November, Valve announcesd the Steam Machine, their first console-like PC that runs SteamOS, a derivative of Arch Linux. But there's also Bazzite, an immutable OS based on Fedora that turns your PC, handheld, or home theater PC into a full game console running Steam's Big Picture mode.

Learn Sewing Machines, they're cool! (Tod #1)

Sewing machines are pretty nerdy, actually. Incredible pieces of engineering. If you've never seen how a sewing machine work, it's amazingly complicated. Yet all that complication is hidden from you and they've worked the same say for over 100 years. I recently took some sewing machine classes, learned a lot, and had a lot of fun.

The standard sewing machine takes two different threads, one above and one below the fabric, and locks them together with a clever hiden mechanism. It does this a hundred times a minute. This lockstitch is very strong and both the horizontal & vertical spacing of the stiching can be easily modified to provide different physical effects like stretchiness. Sewing machines have a wide array of adjustment knobs & levers that can be daunting, but became pretty obvious after the class. The intro class walked us through how differnt settings changed the stich and that, most of the time, you can ignore all those knobs and just use the machine with standard settings.

If you're insterested, you can find cheap classes on sewing machines from community colleges, maker spaces, or even free from family members who sew. My grandma tried to teach me sewing as a little kid and I wish I had paid more attention. The classes were from a local craft-oriented makerspace and they had several other useful upcoming classes, like how to make your own hoodies and sweatshirts. I learned from the people there that many places that offer classes often let you have time on or borrow the machines so you don't even need to buy a machine to sew. But if you did, brand new good beginner machines are around $250. Pretty cheap compared to a much of tech gadgets we buy.

At the moment I'm mostly interested in making a custom bags and dust covers for my gadgets. And maybe sew up holes some favorite pairs of jeans. There's also a few tshirts that are way too boxy and it's really easy to hem them to make them look more tailored.

So yeah, try playing with a sewing machine. You may have one hiding in your house already. There's lots of youtube videos to help get you going too. I've included a playlist in the show notes.

Links:

CAD Round-up (Paul #2)

A round-up of recent CAD news, starting with Hackaday's recent story on BREP.io. BREP stands for brand new, from-scratch boundary representation. BREP.io is a new browser based CAD where all computation is done on the client side, including complex operations like fillets, lofts and more. Check out the story at Hackday, follow the project page, or check out the GitHub repository.

Next up is Microcad, which is very young in its development and is still in alpha. Their home page calls it a new open source programming language that can generate 2D sketches and 3D objects. The easiest comparison is probably something like OpenSCAD. They've got some neat videos of how they're using Microcad to create models, including a logo, LEGO bricks, gears, and more.

Lastly is CADQuest, a website to help you level up your CAD skills. It has a free and paid tier, but I haven't tried it out personally. They claim it works with any CAD software, but it looks like they prefer SolidWorks. So if you're into gamification to level up your CAD skills, it might be worth checking out.

Learn Analog Electronics by Building Synths (Tod #2)

Moritz Klein is an online instructor of analog circuits on Youtube, who also happens to be very good at making analog synth circuits. His most recent video is about how to build a drum sequencer using just chips, no coding. And it's really understandable!
The resulting sequencer is simplified to make it easy to implement, but it's also very usable in its final form.

This video is the latest in his series on building a set of modules to implement an analog drum machine like the venerable TR-808 or TR-606. His videos are approachable and the sounds his simple circuits make really sound good. These videos do assume you know how to read a schematic and have a basic understanding of electronics, but he has another series for beginners that helps get you those skills too.

He also works with the famous modular synth company Erica Synths to make a set of DIY kits based on his videos. One of the interesting kits in that series is their "EDU Labor", which is an breadboard system with useful support circuits for making synths like buttons, knobs, tiny oscilloscope, power supply, and more. You can of course wire up these things yourself (this is what I do), but having the Labor would make getting started much faster.

Even though I've been doing electronics for decades, watching his videos has improved my my analog skills and has helped me think about how to implement emulations of analog synth circuits in code. So if you're interested in how analog synths work or just analog circuits, give his videos a try.

Links:

The Indie Beat FM and Television (Paul #3)

Way back in episode 9, we talked about Radio Free Fedi, the streaming radio station made up of artists on the Fediverse, like Mastodon. Just over a year ago, Radio Free Fedi shut down on January 1st, 2025.

The spirit of RadioFreeFedi lives on in the Indie Beat Radio stations and now Indie Beat Television. The Indie Beat Radio federates with Bandwagon.fm and features over 4000 songs streaming. The Indie Beat Television just launched on December 28th and features videos from Fediverse artists.

Remembering RadioFreeFedi
The Indie Beat Radio
Ways to watch The Indie Beat Television
Bandwagon.fm
The Indie Beat - Fediverse Radio - GNOME Shell Extensions and GitHub repository
Follow The Indie Beat Television on Mastodon: @TIBtv@tv.theindiebeat.fm

'act' to run Github Actions locally (Tod #3)

Do you use Github Actions? They're awesome. By setting up a small YAML config file, Github will spin up a virtual server, run the code in the config file, any time some specific action you do on Github like commit files, publish a version, or create a new tag. This is mostly used for CI/CD tests where every commit causes the code to get recompiled and retested, which is amazing for discovering you just made a breaking change.

But how do you want to that config file code on demand, on your own computer? This is not easy and it's where "act" comes in. Just "cd" to your local repo checkout, run "act", and it will run any github actions you've got specified. Pretty magical!

"act" works via the power of Docker, of course. This isn't exactly like the virtual environments that Github uses for its action runners, but is pretty close. It's mostly for Linux-based actions, but it can do MacOS or Windows actions if you're on one of those systems.

I've found "act" to be great for when I'm trying to figure out exactly how to write the YAML config file for the github action. Normally this means making a change, checking it in, waiting for the action to run on github's servers, then seeing the results. It's pretty slow. And fills up the git history with a bunch of "trying to fix github actions" entries. I have a few test repos that I use just for figuring out how to set up github actions for real repos and still I have git history litter as I try to configure the actions. So I'm hoping "act" will help me iterate faster on github actions on my local servers before I need to touch github's.

Links:

2026-01-032026-01-05

Episode 1 - Rock Stars are Just Like Us

Paul Cutler ([@prcutler](https://hachyderm.io/@prcutler)) — Sat, 03 Jan 2026 12:51:16 +0000

Published: September 26, 2022

Welcome

Welcome to The Bootloader, a bi-weekly podcast bringing you news, project updates, and product talk from the tech and maker scenes. Paul and Tod will bring you three interesting things and chat about them for a few minutes each.

Full transcript available here.

Show Notes

FullControl.xyz (Tod #1) 0:23

FullControl Design Library
FullControl Twitter for most up-to-date news
Original FullControl research paper using Excel & VBA

tio (Paul #1) 2:11

tio, a modern serial terminal (tio homepage)
tio 2.0 Release Notes
Adafruit's Advanced Serial Console on Mac and Linux Learn Guide

Belay (Tod #2) 4:14

Belay library for CPython to remote-control Micropython / CircuitPython
20 second demo video why Belay is cool
Also see, Firmata protocol for Arduino, and Firmata library

Rivers Cuomo (Paul #2) 6:36

Rivers Cuomo, from the band Weezer, is a Python developer! Github profile
Mr. Cuomo's New Albums Python application

CircuitPython Camera Support (Tod #3) 8:57

Bambu Labs X1 Carbon 3D Printer Review (Paul #3) 11:36

Bambu Labs X1 Carbon homepage
Bambu Labs X1 Carbon Kickstarter page
Original Prusa i3 MK3S+ 3D printer for price reference
Community Reviews of the Bambu X1 Carbon:
BV3D review of the X1 on YouTube
Edge of Tech review of the X1 on YouTube

Your financial sponsorship helps with the cost of hosting, recording and transcripts. Thank you for your support!

2022-09-262026-01-03

Episode 2 - M is for Makers, Music, and Machine Learning

Paul Cutler ([@prcutler](https://hachyderm.io/@prcutler)) — Sat, 03 Jan 2026 12:51:16 +0000

Published: October 10, 2022

Welcome

Full transcript available here.

Show Notes

Episode Intro

Paul - thank you and FullControl follow-up * Paul printed the latest model, AnyAngle Phone Stand * Printed flawlessly at double speed! * Thank you to Brian Okken and Michael Kennedy of Python Bytes for the podcast's inspiration.

PixelBlaze expression language (Tod #1) 1:45

Lux Lavalier wearable LED pendant
Lux Lavalier Patterns guide
Lux Lavalier created by GeekMomProjects (Debra Ansell), Ben Henke, Jason Coon
Pixelblaze
Huge online library of Pixelblaze patterns
Fibonacci LED displays
3d-printable magnetic battery holder

Whisper OpenAI (Paul #1) 5:50

Blog post, paper and Google Colab example linked from their GitHub repository
- From OpenAI, who developed Dall-E
Hackaday story
Built with Python 3.9.9 and PyTorch 1.10.1
- Meta transfers PyTorch to Linux Foundation
5 models from tiny size to large - the smaller the model, the faster it is and less memory needed but the fewer words it knows
- Trained on 680,000 hours of audio
Benefits
- Accessibility!
- Transcription
- Text and VTT files
- Translation
MIT Licensed, people already building on top of it:
Downsides
- No Speaker tagging
- Slow if not on GPU

Music generation in the browser (Tod #2) 11:03

SuperCollider, an open source audio programming language from the 90s
TidalCycles, a musiclive coding environment using SuperCollider
Sonic Pi basically an easier-to-install version of TidalCycles
Tone.js in-browser synthesis, used by the following:
Acid Hit
Pi Songs by Canton Becker
Shepard's Pi "Play something no one has ever heard before"
Strudel music live coding
- Example played in show: stack("c4 f3 g4 a#4", "c2 g2".slow(2)).echo(4, 1/8, .5)

PolyKeyboard (Paul #2) 16:41

Poly Keyboard with OLED keycaps)
Keycap demo on Twitter
- Split keyboard design
- rp2040 powered
- Bring your own key switches and keycaps (the flex cable needs to fit though the RGB slit of the key switch)
- Compatibility chart for key switches available - needs 8.MM slit for the LED
- Needs a 3D printed stem
- OLED is custom with a flex cable
Blog and Ko-Fi
- Blog post comparing other keyboards

Samplebrain by Aphex Twin & Dave Griffiths (Tod #3) 21:27

Samplebrain Homepage
Samplebrain manual
Good CDM article about Samplebrain
Aphex Twin (Richard D James) makes weird & interesting techno & ambient music

Kevin McAleer and the Pikon (Paul #3) 23:48

Pikon story on DigitalCameraWorld.com
Kevin's Homepage
- Kevin's YouTube Channel
So many cool projects!
- Robots and more robots!
- Pomodoro Pico W Desk Robot
Kevin's Pikon video
- Blog post
- Raspberry Pi News Story
Next Steps
- Python app for the Raspberry Pi to record video clips, photos and apply filters, and possibly use to livestream.

If you like what you hear, one of the best things you can do to help the show is tell a friend or write a review.

Consider supporting the show financially - your support helps with the cost of hosting, recording and transcripts. Thank you for your support!

2022-10-102026-01-03

Episode 3 - The Middle is a Pumpkin

Paul Cutler ([@prcutler](https://hachyderm.io/@prcutler)) — Sat, 03 Jan 2026 12:51:16 +0000

Published: October 24, 2022

Welcome

Full transcript available here.

Show Notes

Episode Intro

Welcome!

10 cent RISC-V "Arduino" chip! (Tod #1) 00:15

What made Arduino possible in early 2000s: Atmel ATmega168P for $4 and avr-gcc open source compiler
For $4 you got so much! 16 kB flash! 2 kB RAM! RISC architecture! Minimal required external parts!
Now, WCH, the makers of the CH340 USB-to-serial chip that you've maybe seen on some dev boards, has a new chip
Fellow hacker Akiba on Twitter alerted me to this, quoting a tweet from Patrick Yang at WCH
New WCH CH32V003 RISC-V chip
Arduino-class, only $0.10 (48MHz, 2kB RAM, 16KB flash, 18 IO, 8 ADC)
RISC-V is an open-source CPU core that's scalable from desktop-class chips to cheap embedded processors
Similar to ARM cores in our iPhones and Raspberry Pi Picos
But no license fee needs to be paid!
Potential problems tho:
bigger brother CH32V307 needs custom OpenOCD programmer RISCV-OpenOCD-WCH
and only IDE supported is their MounRiver
akiba's tweet that alerted me
CH32V307: slightly better version w/ USB
Micropython for CH32V3
Rust for CH32V3

Jetbrains Fleet (Paul #1) 4:28

Jetbrains, the makers of code editors and IDEs powered by IntelliJ, have released a new code editor called Fleet
Focus on Speed - “fast and lightweight” is how they describe it
Code editor and / OR IDE
- Smart Mode enables IDE features, including code completion, quick fixes and more
Collaboration
- Built-in collaboration tools - 1 button click to start a session and it auto copies the share link for you
Distributed
- You can connect using SSH for example, and it creates an instance of Fleet on the remote computer you connect to
- Or easily connect to a Docker container of Jetbrains’ Space service
I’ve been using it and I like it
It does feel snappy, not sure if it’s in my head or not
As a hobbyist programmer, I probably only use a small percentage of the features found in an IDE, which is one reason why I like this
I used PyCharrm for 4 or 5 years until switching to VS Code for a year, and then switched back to PyCharm earlier this year.
Let’s call this what it is: This is Jetbrains answer to VS Code.
Where VS Code has a number icons on the side, Fleet has a few along the top
And good for Jetbrains! Competition is good, it will drive innovation. If you’re an Atom user looking for a new editor or like to try new things, give it a try, I like using it.
GitHub sunsets Atom

Person Sensor by Useful Sensors (Tod #2) 9:35

Useful Sensors is a new company by Pete Warden, who helped develop Google's open source TensorFlow machine learning platform
Pete is a founder of the "TinyML" movement: putting machine learning on devices you control, instead of in some cloud service
The Person Sensor detects faces, basic facial recognition, can determine "looking at", for $10!
Can remember up to 8 people. But just gives them an ID 0-7, nothing is known about them, just "different"
You get x,y position of face, with confidence percentage, and "is facing" flag!
Uses I2C via Qwiic/StemmaQT I2C connector, so easy!
API is simple, example code in Arduino, RP2040 C, Python
The demo Pete published on Hackster.io uses an Adafruit Trinkey running CircuitPython to lock his computer when looks away
I'm getting a couple of these boards to try out, should be here in a few days
Hackster.io project article w/ Trinkey & CircuitPython
EETimes article about Useful Sensors & Pete Warden
Available now at SparkFun
Developer Guide
CircuitPython example

GitHubCopilotInvestigation.com (Paul #2) 13:38

GitHub Copilot potential lawsuit
GitHub Copilot - Your AI pair programmer
Matthew Butterick, a writer, designer, programmer and lawyer has started an investigation into a potential lawsuit regarding GitHub Copilot
Joseph Saveri Law Firm
Shares examples of problems in both the training of model and Copilot usage
Mr. Butterick states that the objection isn't AI assisted coding, it's how Microsoft went about it.
Participation could have been voluntary or even paid
Microsoft claims it's fair use
Is attribution needed?
Bradley Kuhn of the Software Freedom Conservancy asked Github in June of 2021 for legal references to back up the fair use argument. Microsoft hasn't provided any and Mr. Butterick says that's because there is no legal authority for Microsoft's position.
Copilot users have shown that Copilot can offer a suggestion of code verbatim from another project
Stefan Karpinski exammple tweet
Chris Green example tweet
When we look at Copilot usage, what could the impact on open source communities be?
Mr. Butterick argues that Microsoft is creating a new walled garden that might "inhibit developers from discovering traditional open source communities."
Developers may not need to interact with an open source community in the future when the code they want is just presented to them
Bug and issue trackers, source repositories, mailing lists, etc.
Jamie Zawinski, aka jwz, a co-founder of Netscape and Mozilla
Blog post

CircuitPython’s ulab (Tod #3) 19:18

ulab: Numpy for CircuitPython
In Python, any time you do a for-loop to do math a list of data, you're probably doing it wrong
For some operations, the Python built-ins "map()", "filter()", and "reduce()" can do the work for you
But for really mathy stuff, you need something else. Enter NumPy
If you're experienced with Python, you've probably played with NumPy
Edit images, audio, machine learning, all use NumPy
It's a wrapper around efficient native C code
In general think of Python more like Lego:
- you connect pre-built pieces to solve your problem
- you can try to build everytihng from 1x1s but it's a bad idea
CircuitPython can't have the full power of NumPy (which does linear equation solving, curve-fit analysis, etc)
But it does have "ulab"!
ulab does some of the most important array and matrix operations at near-C speeds
For example: LED animations. a common task is "fade all LEDs a bit"
Cylon effect: Turn LED on, Fade all LEDs toward black, go to next LED, repeat
Firework effect: Turn random LED on, fade all LEDs towards black, repeat
Fakey fire effect: [[ demo this on video ]]
Normally this "fadeToBlack()" would be a for-loop
In normal CircuitPython, this loop on 256 LEDs takes over 40 millisecs!
The same operation with ulab takes around 4 milliseconds: 10 times faster!
Tod's writeup about this
Simple Fire effect w/ CircuitPython & Neopixel matrix
Paul's 32x8 Neopixel matrix using FFT and ulab

MakerDeck (Paul #3) 23:57

MakerDeck Twitch
Twitch livestreams 7-9 3D printers all printing at the same time
Can be anything maker related, such as crocheting or painting
Twitter
Chris Pirillo on Twitch
Live on Twitch everyday at 6pm PST
Huge Star Wars fan!
Crew helping including @pezliz, zombiehedgehog, and @fixumdude
Everything you want to know is on their Twitch page, from What is MakerDeck to how to participate and helpful hints
Wonderful and very active Discord community
- Every channel you can think of from chatting in the Cantina to models to make to showing them off or even tech support if you need help

If you like what you hear, one of the best things you can do to help the show is tell a friend or write a review.

Consider supporting the show financially - your support helps with the cost of hosting, recording and transcripts. Thank you for your support!

2022-10-242026-01-03

Episode 4 - What's the Matter?

Paul Cutler ([@prcutler](https://hachyderm.io/@prcutler)) — Sat, 03 Jan 2026 12:51:16 +0000

Published: November 7, 2022

Welcome

Full transcript available here.

Show Notes

Episode Intro

Welcome!

macOS Ventura cannot copy UF2 files (Paul #1) 00:21

Adafruit Blog post
Raspberry Pi Blog
You cannot drag and drop UF2 and HEX files using macOS Finder - it results in an error
Lady Ada gave a good overview of the technical issues in Ask an Engineer
Two workarounds
- Use the terminal: cp -X blink.uf2 /Volumes/RPI-RP2/
- Install a macOS short created by Alasdair Allen (author of the Rasperry Pi blog post above)
- Shortcut
- Works great! Update Shortcuts settings to allow shell scripts and just right click a UF2 image to transfer it
Help out and file a bug report with Apple!

Matter officially supported in iOS 16.1 (Tod #1) 2:37

What is Matter?
- Matter is an open standard for smart home IoT stuff (Apple, Google, Amazon, etc all signed on)
- Matter 1.0 spec just released (stared in 2019)
- Created by what was the Zigbee Alliance (Zigbee being a BLE-like protocol from a decade ago)
- Matter, however, sits on top of existing WiFi or BLE protocols
- Most examples I've seen are WiFi-based
- IOS 16.1 now just sees them
- Matter was originally called Project CHIP, why their github org is named 'project-chip',
Eric from ThatProject Youtube channel demos it
Eric also posted to reddit in r/esp32
Their Github repo has useful ESP32-based examples
ThatProject Eric also has a great Github Repo of ESP32 IoT projects
~~~Matter pre-compiled example apps from Nabu Casa / Home Assistant Cloud~~~

3D printing for good causes (Paul #2) 7:00

3D Printing for Mental Health and Suicide Prevention Campaign
- The idea was started by a teacher, Abby Brown, at Torrey Pines High School.
- Each year the school has Yellow Ribbon week where students are learn about crisis resources and risk factors for suicide.
- The keychains were designed to give away to her students as a special way to end Yellow Ribbon Week.
- Each keychain contains a word, such as "Smile", "Inspire", "Create", with about 10 different words.
- There's a fundraising campaign where you can print one of the designs found on Cults3D and post it on Twitter and Instagram.
- Different organizations are matching the funds, with an opportunity to raise over $4000 by just printing and sharing!
- Joel Telling, Printed Solid, LDO Motors, and Alien3D
3D Printed Toys for Tots campaign
- Organized by IC3D in 2018, they work with volunteers in the 3D printing community to print toys for kids
- Over 69,000 toys printed in 2021!
- This year they have over 140 volunteers and have printed 27,000 toys so far.
- You can donate financially or sign up to help print toys
- Toys include an articulated alligator, a train engine, cars, low poly dinosaurs, and more.
- The signup period is now over to volunteer for printing, but keep an eye out for this next year.
- Twitch.tv Stream

Hypno "video synthesizer" from Sleepy Circuits (Tod #2) 10:00

Have you ever taken a camcorder and point it at the TV to get weird video feedback?
Have you ever enjoyed those trippy algorithmic screen savers?
You can do both in real-time with devices called "video synthesizers"
I was at Synthplex last weekend and it was fun!
- It's mostly a audio synth convention but there were a few non-audio things there too, like:
Hypno by Sleepy Circuits is one such device
Physically it's a small box with knobs, sliders, and buttons. And an HDMI port! (and NDI over USB for streaming)
Twiddle the knobs & sliders to create generative video patterns
Source material can be video "oscillators", camera feeds, video files
Raspberry Pi 3 or 4-based, with Eurorack-compatible jacks to sync to your music
Been in development since 2019
Extensive documentation and a big community, with an active forum
(Product page](https://sleepycircuits.com/hypno)
Example videos on Instagram

IO Rodeo Launches the Open Colorimeter, a CircuitPython Analysis Tool for Citizen Science - Hackster.io (Paul #3) 13:10

Hackster.io article from Gareth Halfacree
The Open Colorimeter is an instrument with many applications, including measuring contaminants & pollutants in soil & water
- Based on the Adafruit PyBadge
- 3D printed case
- Published under open licenses
- MIT for the firmware
- Physical designs under a CC-4.0 license
- Excellent documentation with product guides and project tutorials
- Example: measure the blue dye in sports drinks
IO Rodeo's mission is to increase accessibility to scientific data collection tools by creating low-cost, open hardware instrumentation.
Open Hardware and Software: GitHub Repository

ffmpeg.guide makes configuring FFMPEG easy (Tod #3) 15:40

https://ffmpeg.guide
FFMPEG is tool used behind-the-scenes by many video processors including MPlayer, Handbrake, VLC
And used by many websites that handle A/V
At it's simplist, it converts video formats (AVI to MP4) but it can do so much more
I use it to:
- Down-convert HDR video to SDR, resample to 720p (for players that don't support HDR)
- Quickly cropping videos in a bit when shooting with a wide-angle lens
- Recompress 4K video to 1080p with reduced bitrate usable by Twitter/Youtube
- Convert audio of any format to .WAV
Example FFMEG commands
FFMPEG can do much more and it's famously complicated to use
It's been around for over 20 years! wow!
"ffmpeg.guide" is a "Flows & nodes"-based GUI for generating FFMPEG commandline commands
Free for up to 5 nodes
Developer post announcing it

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2022-11-072026-01-03

Episode 5 - Pandas and Breadboards

Paul Cutler ([@prcutler](https://hachyderm.io/@prcutler)) — Sat, 03 Jan 2026 12:51:16 +0000

Published: November 21, 2022

Welcome

Full transcript available here.

Show Notes

Episode Intro

Welcome!

Micropython by Arduino Labs (Tod #1)

It works well! Simple and clean, with what you need: code editor + terminal window
Works with any MicroPython device with USB serial, from my limited testing
No serial plotter, no library manager, no board manager. This is a first step
However, it is yet-another-Electron app, so it's fairly pudgy memory-wise
Alternatives:
- Thonny -- beloved by many. I do not like it, find it unattractive and confusing
- Mu -- cleaner and has a nice serial plotter like Arduino IDE
- Any text editor + picotool -- my preferred choice
- What I do not recommend: any "micropython extension" for VS Code/Atom/etc. The ones I've tried are flaky and presume too much, taking over other Python projects

Home Assistant and the State of the Open Home (Paul #1)

Home automation platform focused on local control and privacy
- No vendor log-in
- Your smart home shouldn't require the cloud
State of the Open Home is an annual look at the smart home ecosystem and Home Assistant
- Livestreamed Nov 13, 2022
- 2 open source project on Github by contributor contributions
- Home Assistant Cloud from Nabu Casa processed 50,000 webhooks per second
- 190,000 instances of HA opted in to reporting
- Estimated 500,000 - 600,000 installations of HA
- 2023: Year of Voice
- Rhasspy voice assistant: https://github.com/rhasspy/rhasspy by Michael Hansen
  - Can function completely disconnected from the Internet
  - Are entirely free/open source with a permissive license (MIT)
  - Works well with freely available home automation software
  - Optimized for working with MQTT, HTTP and Websockets with Home Assistant having built in support
  - Support for over 25 different languages
- Hired by Nabu Casa to work on and integrate Rhasspy full-time
- Summary video

WithDiode.com -- 3d breadboard simulation in the browser (Tod #2)

omg. this is the best. so fun
Created by Kennth Cassel
- (who also created a nice Vim tutorial site called vim.so
I saw it first from Clive Thompson (@clive@saturation.social) on Mastodon
I was able to implement some of the oscillators we did during Deep Fried Neurons
- DeepFriedNeurons breadboard oscillators
But... it's actually kinda harder to use than real breadboards
Other tools I find useful in this space:
- Wokwi simulator lets you simulate Arduino, Micropython, and CircuitPython
- Fritzing lets you visually breadboard up circuits, with accompanying breadboard & PCB layout

GitHub in the news (Paul #2)

Follow-up: the investigation has spawned a GitHub Copilot lawsuit
- Verge
Hey Github
- Imagine being able to code hands free
- This could be big for accessibility
- Use natural speech, for example: Saying "Import pandas" results in import pandas as pd
- In the features, Github shares:
- Write / edit code (using GitHub Copilot)
- Go to the next method with code navigation ("Hey GitHub go to line 34 or method X)
- Run the program and control your IDE using any VS Code command
- Code Summarization: Ask "Hey GitHub!" to explain lines 3-10 and get a summary of what the code does

RNBO "rainbow" -- Turn Max patches into VST plugins (Tod #3)

Ever wonder how people make virtual synths / audio effects, or even real synths & effects?
Max is a way to create custom virtual instruments or effects, and custom UI. Make it look like a real thing if you want
Max is often a good solution to mocking up ideas for these, kinda like CircuitPython and Arduino is for microcontroller projects
- Max is a stand-alone application or part of Ableton Live
- It's what's called a "patching environment", a "nodes & flows" graphical programming tool
- The "flows" are audio & MIDI, kinda like modular synths cabling stuff together
- I've used in on-n-off (mostly off) since the 90s (could never quite get into it)
- But Max patches have to live inside Max (or inside Max in Live)
RNBO let's you create a "compilable" versions of Max patch
- It is inclucded with Max or $299 for permanent license or $10/month subscription
- RNBO is actually a parallel thing to Max, but implements most all of Max
- But does Turns any Max patch into a C++-based stand-alone VST
- Can even target Raspberry Pi, so you can make custom Pi-based synths & pedals
- Or can export to Web Audio, with Javascript control!
good CDM article about RNBO
good synthanatomy article too about why this is cool
Online (paid) class for how to use it by Music Hackspace Here's a preview on youtube
Open source alternative to Max is PureData (aka 'Pd')
- Pd & Max have common roots, Pd is a bit rougher looking than Max, but very capable
- And it runs on a Raspberry Pi
- And there's a huge community of existing Pd patches.
- And there's the free online Heavy compiler for Pd patches

Mastodon (Paul #3)

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2022-11-212026-01-03

Episode 6 - Supersized for Supercon

Paul Cutler ([@prcutler](https://hachyderm.io/@prcutler)) — Sat, 03 Jan 2026 12:51:16 +0000

Published: December 5, 2022

Welcome

Welcome to The Bootloader! This week we are doing something a little different. Tod recently attended Supercon and shares some of his favorite talks and presentations. Paul and Tod also share one interesting thing.

Full transcript available here.

Show Notes

Hackaday Supercon

What is Hackaday Supercon?
Annual get together in Pasadena of talks & workshops on stuff you'd see in Hackaday.com
A way for me to see friends I've only really talk to online
It's held at the Supplyframe DesignLab and at Los Angeles College of Music next door
In between is an alley where there's hardware hacking and snacks
The workshops are held at Supplyframe HQ, up the street a few blocks
One of my favorite conferences, before pandemic
This Supercon was first in-person since 2019
It was so nice seeing everyone, but wow I am out of practice being amongst people
The SuperCon Badge
Hacker conferences have these "badges" that don't really function as IDs any more
Instead, they're a playground for electronics experimentation
This year, the badge was a microcontroller-based board that acted like an old switches-and-lights computer from the 1970s.
Designed by Voja Antonic, a Serbian inventor, created the "Galaksija" build-your-own-computer in 1983, inspiring thousands to learn computers
Check out the Video badge walkthrough by Voja
You program it the way computers used to be programed: hand keying in bits one-by-one, and clicking the "load" switch to enter a single machine code instruction, one at a time
Some of the talks I liked
Nick’s DIY Vacuum tubes
Adrian’s Soviet chips
Chris Comb's "How to Hang and Sell Your Blinky Goodness as Art" (on the DesignLab stage, so recorded but not streamed)
Also, Bradley's talk about 'showing up' and making a difference, disguised as a talk on hacking electric scooters
Lastly, Samy's "random walk" exploration that resulted in a flexible wearable tesla coil to light up his breathe in a glass ampule

Python in the Browser (Paul #1)

MicroPython in the browser
Builds on Pyscript, announced this past PyCon by the founder of Anaconda, Peter Wang
Great podcast at Talkpython.fm sharing more, including the technical details
- Included Brett Cannon, Fabio Pliger, and Nicholas Tollervey
Pyscript can use the MicroPython as a runtime
- Reduces the size of Python in Pyscript from 11MB to 300k using MicroPython
- Pyscript is a framework the developers see building on top of
- PyScript Runtimes - MicroPython Technical Preview

PicoStepSeq in The MagPi Magazine! (Tod #1)

My PicoStepSeq project made it as an article in The MagPi
Also in the print version (and the PDF)! (and it's a slightly different, longer article.)
PicoStepSeq is a tiny 1980s-style MIDI sequencer, using these lever switches with embedded LEDs (called "step switches" by Adafruit)
It was desgined, coded, and built in the two weeks leading up to CircuitPython Day 2022
It has both a CircuitPython-firmware and an Arduino-based firmware
See it in action in John Park's Workshop from November 30
I've slowly been considering a 16-step version, but it's complicated for various reasons

If you like what you hear, one of the best things you can do to help the show is tell a friend or write a review.

Consider supporting the show financially - your support helps with the cost of hosting, recording and transcripts. Thank you for your support!

2022-12-052026-01-03

Episode 7 - The CircuitPython 9 Release Show

Paul Cutler ([@prcutler](https://hachyderm.io/@prcutler)) — Sat, 03 Jan 2026 12:51:16 +0000

Published: March 22, 2024

Welcome

Welcome to The Bootloader. We're excited to return after an extended break. For episode 7, we dive into the just released CircuitPython 9 and discuss what we're excited about and some of the new features.

Full transcript available here.

Show Notes

Episode Intro

Welcome! This is all about the new CircuitPyton 9.0 release

What are we excited for in CircuitPython 9?

Tod: jpegio, ESP-IDF update, USB Host, parelleldisplaybus
Paul: Memento camera / jpegio, CIRCUITPY on Android, ConnectionManager, USB Host

`jpegio` and the Memento Camera

Memento Camera from Adafruit
AdaBox 21
- AdaBox 21 Unboxing Video hosted by John Park
jpegio
- one downside of JPEG vs BMP or PNG files: JPEGs are not palletized
- based on "TJpgDec"
bitmapfilter
- Convolusion (kernel) image filter
- Photoshop-like image effects in CircuitPython

USB Host

usb.core
- Tries to be as much like PyUSB as possible
USB MIDI Controllers with USB Host is coming
Keyboards on USB Host
- Scott theorized about a CircuitPython "computer" in his CircuitPython2024 blog post earlier this year

MicroPython and merging its changes into CircuitPython

New split heap management. Here's a comment from CircuitPython Core Developer Dan Halbert:

The "split heap" code from MicroPython now enables us to use heap allocation outside the VM, which was very awkward before: any dynamic storage allocation could only be done once, before the VM started. The heap then used the remaining RAM. Now there is an "outside" heap which can be used while the VM is running, and that storage will not be garbage collected. So various storage allocations that used to be static can now be dynamic, such as stuff needed for USB setup. We also removed the "long-lived storage" scheme that was added a long time ago to reduce fragmentation. In that scheme, storage that we expected to live a very long time (mostly allocations for compiled bytecode) was allocated at one end of the heap, and shorter-lived storage (like the temp storage used during compilation) was allocated at the other end. Part of the scheme involved moving allocated objects and adjusting pointers. The moving caused some inherent but obscure problems where objects' identities seemed to change.

Now long-lived storage is gone, because it was not very compatible with the split-heap scheme. This may cause some projects on small-RAM boards like SAMD21 not to work any more due to increaed fragmentation. We have some ideas for doing something like long-lived storage in a different way that wouldn't involve moving objects, but that won't be in 9.

The MicroPython merges are huge undertakings. Props to the CircuitPython team for even trying to track upstream. For example, the 1.20 update touched 779 files over 250 commits. And they did 3 merges! (MicroPython 1.19.1, 1.20.0, and 1.21.0)

`paralleldisplaybus`

8x faster display using paralleldisplaybus instead of SPI
Currently for ESP32- and RP2040- based chips
e.g. LilyGo T-Display S3 AMOLED and LilyGo T-Display S3

CircuitPython for ESP32 updates to ESP-IDF 5

CircuitPython 9 moves from using ESP IDF 4.x to ESP IDF 5
This will enable new features and new boards, like ESP32-C6
Potential future support for Bluetooth on ESP32 boards that support BLE

ConnectionManager

Paul got his description wrong - ConnectionManager is used by adafruit_requests and MiniMQTT to manage sockets.
Created by community member Justin Myers
It's great how even with Adafruit funding three core developers that it's truly a community project and a community member can add a new library and way of doing things to CircuitPython.
Makes socket tasks easier, like this example

Breaking Changes in CircuitPython

displayio changes:
- display.show() deprecated
- displayio drivers have moved
- See this FAQ
Mounting a filesystem (SD card) requires an existing directory, like CPython
CircuitPython now requires explicit socket port re-use. Use socket.setsockopt(pool.SOL_SOCKET, pool.SO_REUSEADDR, 1), as in CPython.

Support The Bootloader

If you like what you hear, one of the best things you can do to help the show is tell a friend or write a review.

2024-03-222026-01-03

Episode 8 - Built from the ground up

Paul Cutler ([@prcutler](https://hachyderm.io/@prcutler)) — Sat, 03 Jan 2026 12:51:16 +0000

Published: April 29, 2024

Welcome

Welcome to The Bootloader. In episode 8, Paul and Tod discuss learn to solder kits from Carrie Sundra of Alpenglow Industries, building a synthesizer, the Microdot web framework,learning to program ARM Assembly, a follow-up from the very first episode, and learn about capacitive touch sensors.

Full transcript available here.

Show Notes

Episode Intro

Welcome!

00:22 Meet the Maker: Carrie Sundra of Alpenglow Industries (Paul #1)

If you visit the About page on Alpenglow Industries’ website, Alpenglow mission statement is to To Teach You About Electronics Without Gatekeeping. It goes on to say:

We are passionate about representation in electronics - the field is still overwhelmingly white and male with only ~10% of electrical engineers identifying as women. Having worked in the field for over 20 years, we know how much gatekeeping and hostility there can be. We aim to provide a welcoming space where adults can learn about electronics without judgment or any previous experience.

Homepage: https://www.alpenglowindustries.com
Through-Hole Soldering Kits
Surface mount soldering kits: SMT Soldering Kits
YouTube channel: Alpenglow Industries

05:26 SynthUX Academy and Daisy Seed (Tod #1)

Have you ever wanted to learn to make real high-quality synthesizers, not just the low-fi toys I've been goofing around with in CircuitPython or Arduino w/ Mozzi?

Then you should know about Daisy Seed from ElectroSmith : https://electro-smith.com/

Daisy Seed is a little $25 Arduino-looking board that is designed explicitly for audio manipulation and generation. It's becoming a core component of many musical instruments from guitar pedals, to Eurorack modules, to stand-alone synthesizer keyboards.

The Daisy Seed board features a Cortex M7-class chip with 65 MB of RAM, stereo audio I/O at 24-bit @ 96 kHz, twelve 16-bit ADC pins and two 12-bit DACs for controls, and 31 GPIOs. And it fits on a breadboard!

It has a well-done Arduino library, a C++ DSP library, and you can even run Pd and Max patches on it. ElectroSmith libraries provide all the components you need to make a synth: oscillators, envelopes, filters, sequencers, delays, reverbs, etc. And some good docs too!

I've been wanting "level up" my knowledge of Daisy Seed, but I need a push. And that push has been the SynthUX Academy. They're a non-profit based in the Netherlands that offers in-person and online classes for how to make synthesizers. Many of their classes are available for free on Youtube and their class code is on GitHub.

8:08 The Microdot web framework (Paul #2)

The Microdot web framework was created by Miguel Grinberg, who wrote the Flask Mega Tutorial - Flask being a popular Python web framework. Microdot’s home page describes it as “The impossibly small web framework for Python and MicroPython” and is inspired by Flask. What’s interesting is that it can run on both CPython as well as a microcontroller running MicroPython.

Microdot project page: https://github.com/miguelgrinberg/microdot
Microdot documentation
The Flask Mega-Tutorial: The Flask Mega-Tutorial, Part I: Hello, World!
MicroPython awesome-list for web servers: Awesome MicroPython

10:25 ARM Assembly Deep-dives by Carlynorama (Tod #2)

What's lower-level programming than CircuitPython? Arduino maybe? Lower-level than that? Probably C code calling a C vendor SDK. Now what's lower than even that? C code manipulating a chip's I/O directly, I'd say. And the lowest level? Assembly language.

Carlynorama has been doing a deep-dive on ARM assembly language lately. (disclosure: she's my wife)

She started with an ATtiny45 in bare AVR C to set up the chip and blink an LED. She's really familar with AVR from the original Arduino, so it was a natural jumping off point. On AVR, doing bare C to twiddle chip registers is very close to assembly language, since much of the work is figuring out which registers to twiddle to make something happen. Besides her real target was ARM chips.

For the SAMD21 ARM chips like what's in the QT Py M0 or Trinket M0, she decided to start with assembly, in order to really understand how these chips work compared to AVR. The Cortex-M0+ ARM chips are more complicated than AVR, and the ARM instruction set is huge. But (confusingly) the Cortex-M0+ core in these chips only get a subset of the ARM instructions, making all the documentation about "ARM assembly" frustrating to read until you know which instructions are allowed for your chip.

But in about a week she's gone from knowing no ARM assembly to getting an M0 chip up and blinking an LED, reading a button input, and being able to monitor it all via GDB. Along the way she's been using online ARM simulators and teasing how STM32 ARM chip setup differs from SAMD21 setup.

I've been watching from the sidelines, learning a little along the way, following her blog. And it's been fascinating. You can really see how enormously powerful these chips are when you're down at the lowest level like this. It makes you appreciate all the work that's going on when you say pinMode(pin, INPUT_PULLUP) or button = DigitalInOut(board.GP14).

Her next steps I think are moving to some bigger ARM chips and to try out the Clang/LLVM compiler system instead of the GCC-based tools she's currently using.

19:20 One Year With the Bambu Labs P1P (Paul #3)

Paul shares his experience after owning a the Bambu Labs P1P 3D printer.

The Bootloader Episode 1: Episode 1: Rock Stars are Just Like Us
Bambu Lab P1 Series | Reliable Out-of-the-Box Performance
P1 Series
Bambu extends software and bug fix support until 2027 and 2029 respectively in a turnaround Reddit thread

23:08 Let's talk about Capacitive Touch Sensors and Sliders (Tod #3)

I have been experimenting with capacitive touch sensors for a while now. They can be a really fun and easy sensor to add to your project and require almost zero extra components if you have something like CircuitPython's touchio library to help out.

Captouch sensors work by treating the touch pad as a capacitor that the microcontroller charges up (by setting the pad's pin HIGH) and then seeing how long that capacitor takes to discharge and go LOW. When you put your finger on the pad, the capacitance increases and it takes longer to discharge. By watching for that change you tell "touched" from "untouched".

My latest fascination has been with capacitive touch sliders, either linear or rotary. The rotary slider is like what the iPod had for many years: slide your finger around it like you're spinning a little record.

How do these work? There's a couple of different ways but the method that I've been trying out lately is the "interpolation" technique. This is where you use two or more interleaved pads and measure the comparative touch amounts between them to interpolate a position along them. Imagine splaying your fingers on each and and interleaving them: as you go from left hand to right hand, it's 100% your left hand, then 75% your left hand, then 50/50 both hands, then 75% your right hand, and finally 100% your right hand.

I've got a few projects that have touch pads laid out like this if you'd like to play yourself:

https://github.com/todbot/touchwheels
https://github.com/todbot/picoslidertoy
Tod's Tindie Store

At the bottom of the "touchwheels" page are some useful links to the capsense design guidelines I've been heeding like this one: AN2934 - Capacitive Touch Sensor Design Guide (PDF)

Support The Bootloader

If you like what you hear, one of the best things you can do to help the show is tell a friend or write a review.

2024-04-292026-01-03

Episode 9 - Beautiful Bezier Curves

Paul Cutler ([@prcutler](https://hachyderm.io/@prcutler)) — Sat, 03 Jan 2026 12:51:16 +0000

Published: June 3, 2024

Welcome to the show

Full transcript available here.

00:20 M5Stack Cardputer (Tod #1)

M5Stack Cardputer
ESP32-S3-based (WiFi & BLE) little 'portable computer' w/ display and keyboard in a little case
But it also has: microphone, speaker, microSD slot, IR, 1400 mAh battery & magnet & Lego connection
Only $30!
Keys are very tiny
Included "apps" on the demo program are: BLE keyboard, Python REPL, ...
Available in the US from Electromaker.io which ships from Mouser
Also, supported on CircuitPython!

4:29 RadioFreeFedi and Faircamp (Paul #1)

Some of Paul's picks: * Shannon Curtis * implicit memories, by she hacked you * Loriol (Piano by Johann Bourquenez) * Allflowers

9:55 PlumPot KiCad Tutorials (Tod #2)

I have finally made the jump from Eagle to KiCad. After 20 years of Eagle. A video series that really helped me was PlumPot's video playlist on Youtube.

PlumPot KiCad Tutorials
PlumPot is Keri PLUMstead and JP POTgieter
Goes from installing KiCad, to creating symbols & footprints to to ordering PCBs with gerber files
An older series (KiCad 5), but still really helpful
Because goes into some of the tricky details that haven't changed much, like adding 3d files, clearance & track rules, blind vias, differential pairs, and more

15:31 Meet the Maker: André Costa (Paul #2)

André Costa is the creator of rpilocator and the Pico W Air - Wireless Air Quality Monitor.

18:09 Algorithm videos by Freya Holmér (Tod #3)

Freya is a game dev who codes tools and shaders for Unity but also creates these highly instructive and very beautiful videos about algorithms that are useful in game design but also in generative art and embedded computers.

"Lerp smoothing in broken" -- Lerp ("linear interpolation") is used to smooth movement of an on-screen element It's similar to a common sensor filtering technique called "exponential smoothing" and both suffer from similar issues when the "frame rate" or "sample rate" change.
"The Beauty of Bézier Curves" -- Bezier curves always kinda mystified me, this video shows how they work.
"Why can't you multiply vectors?" -- In the microcontroller space, if you use attitude sensors (gyros/accelerometers) or are making a little game (like my circuitpython-staroids, you'll need to know how to manipulate vectors. This video breaks down how vectors work, shows how to modify and combine them to get what you want.

23:16 CircuitPython Online IDE by River Wang (Paul #3)

2024-06-032026-01-03

Episode 10 - Four Topics and an Interview

Paul Cutler ([@prcutler](https://hachyderm.io/@prcutler)) — Sat, 03 Jan 2026 12:51:16 +0000

Published: July 1, 2024

Welcome to the show

Full transcript available here.

Level up at CircuitPython (Paul #1)

Professor John Gallaugher of Boston College recently released two videos related to CircuitPython: The first is for how to migrate from using Mu in CircuitPython to using PyCharm with tio and the second covers using circup to install and update CircuitPython libraries.

Professor Gallaugher interview on The CircuitPython Show
Professor Gallaugher's YouTube channel
CircuitPython playlist
Raspberry Pi Pico tutorials using CircuitPython
Bluefruit School - using a CircuitPython Bluefruit and tutorials
Use PyCharm with CircuitPython on macOS video
Easily install or upgrade CircuitPython Libraries with Circup video

Embedded Swift (Tod #1)

Apple has been developing the Swift programming language for the last 10 years. They now use it on all their platforms and is the officially-recommended way to write apps for iPhone, iPads, Apple Watch, etc. Swift is heavily influenced by Haskell and Rust, which emphasizes type safety and functional programming, allowing the compiler to catch many bugs before the code ever runs. It was initially created by Chris Lattner, who also developed LLVM and the Clang compiler, which has been a revolution for compiled C-like languages.

Now Apple has released Embedded Swift, a version of Swift that runs on microcontrollers. They have demos for the Raspberry Pi Pico, ESP32-C6, nRF52840, and STM32.

These are pretty exciting, especially the Matter examples they've provided. (Matter being a new standard for home automatition, and part of Apple's HomeKit API) The Swift Matter example for adding a "smart light" controllable with Siri or other home assistants is only about 60 lines long.

https://www.cnx-software.com/2024/06/13/embedded-swift-esp32-c6-raspberry-pi-rp2040-stm32f7-nrf52840-microcontrollers/
https://www.hackster.io/news/apple-embeds-swift-into-hardware-125131557514
https://www.youtube.com/watch?v=LqxbsADqDI4
Swift Embedded Examples - https://github.com/apple/swift-embedded-examples
Swift Matter Examples - https://github.com/apple/swift-matter-examples/tree/main/smart-light

Accessibility Matters (Paul #2)

A new prototype for the Micro:bit and a new Adafruit product to help those with limited or different mobility:

CadQuery (Tod #2)

I've been on a journey to move to open source tools for my engineering work. I use Fusion360 for my 3D CAD modeling. It's pretty good but I'm always irritated after using it. CadQuery is a tool for building parametric 3D CAD models, but you do it all in text, no GUI. Similar to OpenSCAD, but its language is standard Python, available as a library. And can export STEP! Not just STL, making its output useful in engineering contexts.

https://cadquery.readthedocs.io/en/latest/intro.html -- good intro
https://github.com/CadQuery/cadquery -- the main repo
https://github.com/CadQuery/CQ-editor -- GUI editor, like OpenSCAD, one of the many ways to use CQ
https://github.com/Wren6991/CQCAD -- Luke Wren (ASIC designer at Raspberry Pi)'s collection of CQCAD parts
Also similar: OpenJSCAD but also cannot export STEP
And the original: OpenSCAD

Justin Myers Interview

Interview with Justin Myers, author of the CircuitPython ConnectionManager library * ConnectionManager

2024-07-012026-01-03

Episode 11 - Teardown 2024 with Debra Ansell

Paul Cutler ([@prcutler](https://hachyderm.io/@prcutler)) — Sat, 03 Jan 2026 12:51:16 +0000

Published: August 5, 2024

Welcome to the show

00:28 Teardown 2024 recap with Debra Ansell aka geekmomprojects

Debra attended Teardown 2024 hosted by Crowd Supply in Portland, Oregon, June 21 - 23, 2024. Debra shares highlights from the conference and what made it special. * Find Debra on Mastodon and Instagram. * Building Up Excitement for Teardown 2024 * Teardown 2024 * Makers mentioned by Debra: * Jason Coon * Charlyn Gonda * Ben Hencke * Joey Castillo * Carrie Sundra

Pictured: Debra Ansell (left) and Alie Gonzalez (right) display Debra's LED jacket installation at Teardown 2024.

14:17 Tulip Creative Computer and Amy synth library (Tod #1)

Okay another DIY synth thing. I'm a big fan of synth libraries for microcontrollers. My favorites are Mozzi for Arduino and CircuitPython's synthio, but I've also use Teensy Audio Library, Daisy, and others. All have the startup issue of "how do I get things wired up to make sound?" and then they require a good amount of programming & synthesis knowledge too.

The Tulip Creative Computer project tries to solve these problems, and many others. I've been following Tulip and it's gotten really interesting. Tulip is an ESP32-based device you can buy right now for $60, which includes a 7" touchscreen, high-quality audio DAC, MIDI I/O, and a battery. It runs a custom version of MicroPython and is made to have a USB keyboard plugged right into it so you can code on it directly, no computer needed!

As you code it in MicroPython, it can be like a live-coding music environment, sort of like SonicPi, but without the hassle of getting a Rasperry Pi running. Tulip boots up instantly.

Oh and did I say it's a device? It's also a fully-open source project you can build yourself from an ESP32-S3 and touchscreen and the Tulip designers provide multiple guides depending on what hardware you have.

And to get back to synth libraries, Tulip uses the AMY synth library, which has bindings to both Arduino and Python. It's a fascinating take on a synth library, going in a more high-level direction than Mozzi and synthio and is extremely cross-platform.

I have a Tulip coming my way in the next week.

18:27 More new IDEs - ViperIDE and Zed (Paul #1)

ViperIDE

Continuing my review of various IDEs, ViperIDE is a brand new IDE in a web browser focused on MicroPython, with CircuitPython support created by Volodymyr Shymanskyy. You can connect a board in a variety of ways including USB, Bluetooth, and you can use WebREPL to connect over the local network or even the internet. It's a true IDE in a web browser with advanced features including syntax highlighting, auto expanding and minify of JSON, a terminal, and MicroPython package support. It also features a full MicroPython emulator with an example and it uses MicroPython compiled to Web Assembly. * ViperIDE * Zed GitHub repository * Review from Les Pounder at Tom's Hardware * Live demo with Volodymyr Shymanskyy on Tom's Hardware Pi Cast

Zed

Zed is a fairly new code editor and IDE for macOS and Linux users who might miss Atom or Sublime Text. It's open source, released under the Apache and GPL 3.0 licenses, and focused on speed and collaboration.

23:03 CeraMetal: 3D Printing Metal with Bronze Clay (Tod #2)

I was happy to see my friend Leah Buechley mentioned on Hackaday recently. Leah is a professor at University New Mexico and for the last few years has been applying CNC and advanced mathematical techniques to ceramics and clay, creating shapes with overhangs and angles that I wouldn't think possible in clay, let alone 3d printer plastic. They use commercially-available clay 3d printers with some special tricks.

(If her name is familar, she is also creator of the Lilypad Arduino sewable electronics system about 15 years ago, the echos of which we see in the CircuitPlayground Express boards from Adafruit)

Her team's newest project is called "CeraMetal", a way of 3d printing metal on the desktop using a custom metal clay. Once it's printed, it's fired in a kiln and sintered into a solid metal part. The custom metal clay is made from metal powder, xanthum gum and a few other ingredients, mixed together.

To slice the model to be printed, standard slicers like Cura can't be used. Once the CeraMetal clay starts extrusion, it just keeps coming out. Normal slicers stop extrusion and do travel moves. So they had to write their own slicer to support this continuous extrusion aspect of the material.

The print resolution is close to standard PLA printing: 0.6mm nozzle, 0.3mm layer height. The costs are around $2k, for printer and kiln, compared to the $50k-$130k for a Selective Laser Sintering (SLS) machine.

And as an aside, they mention the algorithm used to get equal area spacing in their slicer is Fermat Spirals. These are space-filling curves that have the property that the area between its lines are equal. Perfect for 3d printing. I love spiral algorithms and so I've been looking into these. Links in the show notes of a few Fermat Spiral toys.

27:08 CircuitMatter (Paul #2)

Matter is an open source standard managed by the Connectivity Standards Alliance for IoT devices. It requires a Matter controller such as some Google Nest devices, Apple Homepod or AppleTV, or some Amazon Echo devices. For example, you can buy a Matter-supported smart bulb and set it up with Apple HomeKit, Google Assistant, or Amazon Alexa—without having to worry about compatibility.

Scott Shawcroft, CircuitPython's lead developer, shared he is working on CircuitMatter, a pure Python implementation of some of the Matter specification that will be compatible with CircuitPython and potentially MicroPython.

29:47 Special Announcement about CircuitPython Day 2024

Tune in to the Adafruit YouTube channel on CircuitPython Day, August 16th for a special live stream of The Bootloader with Paul and Tod. Keep an eye on the Adafruit Blog for the schedule and see you there!

2024-08-052026-01-03

Episode 12 - From Arcade to Synth

Paul Cutler ([@prcutler](https://hachyderm.io/@prcutler)) — Sat, 03 Jan 2026 12:51:16 +0000

Published: September 2, 2024

Welcome to the show

Welcome to a new episode! Paul and Tod recap the recent CircuitPython Day, chat about a new synth Kickstarter, arcades, a bug in the Raspberry Pi 2350, and Bambu Lab gets sued.

We've started a new newsletter. Get behind the scenes info about the podcast, links we liked but didn't make it into the show, and learn what we're up to. Sign up or view the archives and subscribe via RSS. Each newsletter is spam and tracking free and is emailed out a couple days after a new episode.

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Small CircuitPythonDay2024 recap

Thank you to everyone who listened to our first live episode on CircuitPython Day. You can stream it on the Adafruit YouTube channel. Paul and Tod recap the live episode including a look back at the last year and some of the projects they worked on.

Show Notes

3:00 MICRORACK: solderless breadboard modular synth parts (Tod #1)

I recall seeing some noise about MICRORACK during Superbooth a few months ago, and lately I've been inundated by Instagram ads for its Kickstarter campaign.

"MICRORACK" is a collection of fully-assembled PCB modules that plug into a solderless breadboard. These modules comprise the same parts in modular synth setups: oscillators, filters, envelope generators, LFOs, sequencers, etc., but Microrack modules are small, cheap, and hackable. They're just exposed PCBs, using the solderless breadboard as a mounting plate and for power distribution.

While I'm a big fan of Eurorack modular synths, I have a hard time recommending it to newcomers because it's so expensive to get even a basic sound. This could bridge that gap. Microrack looks to be compatible with Eurorack and by its nature, it's compatible with the kind of random breadboard-based music hacking I do in Arduino and CircuitPython.

And you don't need Microrack to do modular synth stuff on a breadboard. I do it all the time, but it's kind of annoying: interfacing to other gear is flaky, jacks & knobs aren't breadboard-friendly, input & output level conversion is tricky, etc. Over the years there have been various attempts to make this easier. I've linked a few in the show notes.

Microrack links: * MICRORACK Kickstarter * MICRORACK demo videos * Sonicstate interview w/ MICRORACK at Superbooth

8:16 Pimoroni's Picade Max Arcade (Paul #1)

Paul has been talking about building a standup arcade for years. Pimoroni just launched the Picade Max, a bar top arcade you assemble yourself for £495 or about $650. It works with the Raspberry Pi and includes a 4:3 19" screen with HDMI driver board. It includes everything you need to get started, minus the Pi, such as joysticks, buttons, and speakers. The Picade Max Control Board is the interface to the Raspberry Pi 5 and is itself powered by an rp2040 and works just like a normal gamepad / keyboard. The sound is also powered by an rp2040, the Picade Max Audio Board, that acts as a USB soundcard with 3 watts of power and a rotary encoder on the rear to control the volume. It's powered by the Power HAT for the Raspberry Pi.

Paradise Arcade Shop
Picade Max at Pimoroni
Tom's Hardware coverage and review
Tom's Hardware Pi Cast with guests Paul Beech and Phil Howard of Pimoroni

### 13:17 Pico2 / RP2350 GPIO Input issue (Tod #2)

To start: I would not recommend using the Pico2 or other RP2350-based boards for new users. There's some weirdness going on in the silicon of the new RP2350 chip that makes inputs sometimes not return the correct logic value. Instead, an input may get stuck HIGH with no easy way to recover.

I found this out because the way touchio works in CircuitPython: it takes a GPIO pin, turns it to an output and sets it HIGH, then it turns that pin to an input and waits for it to go LOW. The time that takes is an indication of if that pin was touched. I filed a CircuitPython bug, discovered there was an "RP2350-E9" errata in the chip that seemed to only cover the case when using the internal pull-down resistors, but which also seemed to be affecting us. I couldn't find a way around it after hacking a few hours in the CircuitPython internals for digitalio. Then Dan Halbert looked into it and filed a bug both with Micropython and with Raspbery Pi. This then was confirmed by Philip Howard at Pimoroni and Ian at Dangerous Prototypes (maker of Bus Pirate).

Thankfully Hackster wrote up an article about it, but I think it downplays the issue a little. I don't see how this can be fixed in software and will limit the kinds of circuits we can use the RP2350 with.

From what I can tell the following uses will not work: - Certain ways of wiring button inputs - Capacitive touch sensing - Bit-banging open-collector protocols like I2C

Links: * My original touchio CircuitPython issue * MicroPython issue filed by DanH * pico-feedback issue filed by DanH * Bus Pirate Mastodon post referencing it * Hackster article about RP2350 GPIO issue

18:36 Stratasys sues Bambu Lab over 3D printing patents. (Paul #2)

Stratasys, an early pioneer in 3D printing who also acquired MakerBot in 2013, has sued Bambu Lab. The lawsuit focuses on PEI-coated build plates, purge towers, and automatic bed leveling. These features are common across multiple 3D printer brands, so why sue Bambu Lab? * Tom's Hardware - Is Bambu being targeted for being successful? * Adafruit coverage including suggesting a prior art database

2024-09-022026-01-03

Episode 13 - Welcome Liz Clark

Paul Cutler ([@prcutler](https://hachyderm.io/@prcutler)) — Sat, 03 Jan 2026 12:51:16 +0000

Published: October 7, 2024

Welcome to the show

Welcome to our first guest, Liz Clark aka BlitzCityDIY. Liz, Paul, and Tod chat about a new iOS app from Adafruit, the new Raspberry Pi AI camera, maker skill trees, and more.

Join our newsletter! Keep up with the show and what Paul and Tod are up to. Visit The Bootloader's newsletter page to browse the archives or subscribe.

You can read the entire transcript here.

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Show Notes

00:25 Adafruit itsaSNAP iOS App (Liz #1)

I have to say I'm a little biased with this pick because I contract with Adafruit, but I'm mildly obsessed with the new itsaSNAP app. This is the latest iOS app from Adafruit by our iOS developer Trevor. It acts as a bridge between your iOS device and your Adafruit IO feeds. There is support for Apple Shortcuts, which means that you can log health data, home data, any data that's on your iOS device. You can also read feeds from the device and have Adafruit IO affect tasks on your phone. I've worked on two guides with it so far. The first uses a Qualia board with a round display to show photos from my photos app. I'm able to encode the photo in a Shortcut, send it to an IO feed and then decode it with CircuitPython. I've also worked with using Matter devices in Apple HomeKit with itsaSNAP to log sensor data and also to control an RGB light strip. I'm really excited about all of the functionality and I'm looking forward to seeing what people do with it.

5:09 Raspberry Pi AI Camera Module (Tod #1)

There is a new camera module from Raspberry Pi. It's an "AI" camera. What does that mean? It appears as a regular camera to the Pi, plugs into the CSI camera port. The "AI" part is that it has an RP2040 and 16MB of flash to store a pre-trained AI model you upload to it.

This is the kind of Machine learning (oh I mean "AI") I prefer: on the edge, at the device, rather than in the cloud. The ML models live in the camera module. Results are delivered frame-synced alongside regular camera data over I2C.

You upload models via I2C too. It takes several minutes to upload an 8MB model. And like all these AI models are static, they don't learn: their categorization is baked-in. This is expected but I think means you can't use newer techniques with models that learn.

There's really good docs so far. Easy-to-use command-line tools and a nice Python library.

10:05 The Bumpin' Sticker by Guy Dupont (Paul #1)

Guy Dupont creates his take on the "Keep Honkin' I'm Listening to..." bumper stickers. Using a Raspberry Pi Zero 2W, a screen from Ali Express, a Particle IoT board, and his Last.fm account, the screen dsiplays a bumper sticker with what Guy is currently listening to. * Guy Dupont on The CircuitPython Show * Guy Dupont MakerChat on CircuitPython Day 2024 * The Bumpin' Sticker YouTube video * GitHub Repository * Guy's latest project: Meet @slambot

13:40 Nothing To See/Hear : Wireless Fuzz Pedal (Liz #2)

I follow quite a few guitar pedal folks on instagram and saw the newest post from @different.noises last week. It's a "wireless fuzz" that completes the circuit by transmitting it via an infrared LED. The circuit converts the signal from the guitar to headphone audio level and then again into light that is sent out the infrared transmitter to an infrared LED. He includes the schematic in the post as well as an explainer and a few demo videos to prove that the signal is in fact transmitting via infrared. - Nothing To See/Hear : Wireless Fuzz Pedal Post - different.noises on Instagram

16:10 X1Plus alternative open source Bambu X1 firmware (Tod #2)

I've been thinking of getting a new 3d printer. My Prusa mk2.5s has seen better days. And I'm wowed at the literal 2x speed improvement I could get out of a Prusa mk4s or a Bambulab X1. So when I discovered this X1Plus alternative firmware for the X1, I was intrigued.

The X1Plus firmware runs on the "application processor" (AP) board of the X1, (sort of like what Octoprint does for me currently). It doesn't touch the motion control system. And seems like all does to the the AP firmware is patch the bootloader to also look for a firmware file on the SD card, and use that if present. So you can always go back to stock firmware quickly.

And the team behind it have started a CrowdSupply campaign for an expansion board X1Plus can use for extra features light lights and cameras. I don't think I'd want this, but I'm glad they're finding a funding path for the keep them going.

Also to consider: Craftcloud 3D printing service

I've done a few runs using Craftcloud and the results are pretty good. Like renting a Bambu. Craftcloud is a service front-end for a bunch of additive manufacturing companies across the US. Some offer metal as a material. Their quoting system is pretty easy just to get an idea of the cost. As an idea of costs: it costs about $4 per piece (inc shipping) for a typical synth enclosure.

22:31 Maker (and more) Skill Trees (Paul #2)

Steph Piper aka Maker Queen has created Maker Skill Trees as a way to track your progress across a range of skills. These include things like PCB Design, 3D Printing and Modeling, and Dev Boards to crafting skills like Crochet, Knitting and more. There are almost sixty different skill treens to pick from. Each skill tree has 73 skills or experience hexagon tiles, with basic skills at the bottom to more advanced skills at the top.

There's a web app to create your own skill tree apps designed by Shane Gadsby.

There's also a book in development with an even more expansive range of skill trees, tools to track your progress and calculate your life score across all areas.

2024-10-072026-01-03

Episode 14 - Welcome Kevin Santo Cappuccio

Paul Cutler ([@prcutler](https://hachyderm.io/@prcutler)) — Sat, 03 Jan 2026 12:51:16 +0000

Published: November 4, 2024

Welcome to the show

Welcome to our second guest, Kevin Santo Cappuccio, the creator of Jumperless.

Join our newsletter! Keep up with the show and what Paul and Tod are up to. Visit The Bootloader's newsletter page to browse the archives or subscribe.

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Show Notes

00:27 Welcome Kevin Santo Cappuccio and the Jumperless v5

Kevin is the creator of the Jumperless breadboard and we were thrilled to have him on the show. You can follow Kevin on Mastodon here.

6:20 The UNO Plus+ (Kevin #1)

The UNO Plus+ from John Loeffler is what the Arduino UNO should've been all along. It's the same shape and hardware as the Arduino UNO, with the added bonus of LEDs on every pin to show you the state.

I like shoveling a bunch of decorative LEDs onto things as much as the next guy, but I think when you're actually using them to convey information while still looking nice, it's 1000 times cooler.

The whole "is this pin actually doing what I think it should be doing?" thing while debugging is sooo common. I really thought it would become less of an issue as I gained experience, but I'm pretty sure it happens to me even more now.

If John could code, and was just using another microcontroller and addressables, I wouldn't trust this thing as far as I could throw it. But luckily, he can't. So he did the whole thing with ton of LM339 comparitors, and I'll trust the hell out of those. [They came out in the 70s, so I'd grant them honorary 7400 series status as far as chips go.] If that LED is on, I'd be as sure as I am of anything that the pin is high.

Another cool thing he did was to make the plastic header shrouds out of clear plastic with opaque separators to act as a light pipe. So it's not like an LED next to a pin lighting up, the pin itself is. It's a weird way to put it, but it kinda feels "immersive"?, like the pin lighting up is also what makes the signal go high.

And taking advantage of how cheap full color PCBs have gotten, along with the huge surface area of an Arduino UNO, he actually puts the full pin reference on the board, like the one you'd find on the internet with the alternate functions for all the pins and stuff. I have no idea why Arduino didn't do that originally, but then again, the Unos' pin headers are misaligned by twentieth of an inch so what should we expect.

10:36 Manyfold (Paul #1)

Manyfold is a self-hosted solution to organize and share your files for 3D printing. It's also connected to the Fediverse, allowing you to follow instances (aka server) or creators. You can run it in single-user mode or multi-user. You can also make files public or private, which is great for saving models you might have paid for but don't or can't share publicly.

Suported file formats include 3MF, Blender, FreeCAD, OpenSCAD, STEP, STL, OBJ, GCode, BMP, GIF, JPG, PNG, SVG, and even video files in MP4 or MPEG. It also support Markdown, PDF, and text files.
Demo instance
Public instances
GitHub repository
FLOSS Weekly podcast episode with James Smith

13:52 Quake on a SparkFun Thing Plus Matter board (Tod #1)

next-hack.com got Quake running on a Feather-sized board

We've all seen the "Doom ported to insert tiny electronics here". Those are all good hacks. Doom's game engine isn't real 3D though, more like 2.5D: the enemies are 2D sprites and level geometry is perturbations of a 2D plane. But the game Quake, id software's follow-up effort, was real 3D: fully-polygonal monsters and game world. Real 3D can be tough, so I figured it'd be awhile before we saw a port of Quake to tiny microcontrollers.

And yet, the folks at nexxt-hack.com have Quake running on a SparkFun Thing Plus Matter board. This board is in the Feather format (0.9" x 2") and sports a MGM240P wireless module for doing Bluetooth and Matter wireless protocols. This module also sports a EFR32MG24 chip, which is a 32-bit ARM Cortex-M33 processor at 39 MHz, 1.5MB flash and 256 kB of RAM. (This is essentially the same specs as the new RP2350 from RasPi, so maybe we'll see Quake on an Adafruit Feather soon?)

After proving the idea using the SparkFun board, they designed a complete Quake-playing gamepad with built-in screen, joysticks, sound, and battery. This time using the Arduino Nano Matter board (which has a similar MGM240-series module on it) Oh also: you can do BLE-based multiplayer and it runs at 35 fps at 320 x 240.

This is so impressive since the original Doom required a 486 with 4 MB of RAM, and they're doing it in 256 kB of RAM with a Blueooth stack!

You can download the schematic, board files, and bill-of-materials from their site if you want to build your own.

18:00 Evolvable Hardware (Kevin #2)

Evolvable Hardware

Been around since 1990
Developed at the University of Sussex by Adrian Thompson
Used a XE6200 FPGA (100 gates - 10x10 FPGA)
Project IceStorm is reverse engineering a modern FPGA

23:18 FlexiPi Kickstarter (Paul #2)

The FlexiPi is a new Raspberry Pi Pico with a few tricks up its sleeve. First - it's flexible, hence the name and wafer thin. It also includes a few upgrades from the original Raspberry Pi Pico, including using USB-C instead of Micro-USB and a programmable Neopixel built-in. Otherwise, the pinout stays the same as the popular Pico.

It currently has a Kickstarter campaign running through November 24th. It also includes three digital books with it: Getting Started with a Raspberry Pi PIco, and MicroPython and CircuitPython guides. They've already reached their funding goal, having raised about $7000. Remember, it is a Kickstarter and backing the project doesn't always guarantee delivery.

Update Since recording, the FlexiPi Kickstarter project was suspended by Kickstarter and the reasons why are unknown. To stay updated on the project, you can sign up for their newsletter here.

Tom's Hardware coverage

25:11 EMMG MIDI Synth (Tod #2)

A hacker in our community, Johnathan Bisson / @bjonnh, created the EMMG Midi Synth as a teaching tool for a Workshop on MIDI and music synthesis at the Pumping Station One hackerspace in Chicago

The workshop taught what MIDI is, from down at the signalling level to how it's used by performers. The board each student got was custom-designed. It has 8 pots, 12 captouch pads, an OLED display and stereo audio out, all driven with a USB-C 16MB Pico clone. The workshop also talks about how GPIOs work and how capsense works. Looks like it was pretty great!

And the board has a secret mode: if you power it up with a switch held down, it's also a full synth using the really interesting Pra32-u synth engine for Pico. It's four voice paraphonic with built in chorus and delay effects. It sounds realy nice.

But selfishly what brought this to my attention is Johnathan sent me one! He based his design on a few of my experiments, my "pico-test-syth", "picoslidertoy", and "eight-by".

By having 8 pots instead of two, his board solves one of the ongoing problems I've been dealing with for "pico-test-synth": pots are terrible if you want to have them control multiple parameters. They're absolute controls, unlike rotary encoders. So you have to keep saving "pot position" state any time you change the set of parameter. I should've used rotary encoders or just went with more pots.

The designs for his board are all up on the project github, including a nice writeup of his development process and the OpenSCAD files for the custom knobs he made.

EMMG MIDI Synth homepage
Workshop notes
Workshop slides
Pra32-u synth engine
pico-test-synth – my test platform for playing with synths on a Pico
picoslidertoy
eight_by – my yet-to-used take of adding 8-pots to a single analog in using analog mux chip

2024-11-042026-01-03

Episode 15 - Supercon 2024

Paul Cutler ([@prcutler](https://hachyderm.io/@prcutler)) — Sat, 03 Jan 2026 12:51:16 +0000

Published: December 2, 2024

Welcome to the latest episode! Paul and Tod discuss the recent Hackaday Supercon, including talks they enjoyed, the Supercon badge, and add-ons for the badge.

Join our newsletter! Find out what Tod and Paul are up to and they share links to stories that didn't make it into the podcast.

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Show Notes

Hackaday Supercon

Hackaday Superconference ("Supercon") is a 3-day conference that happens every year in Pasadena around the end of October at the Supplyframe DesignLab and its neighbor, the LA College of Music. About 500 people get together to hear a collection of talks on two stages from the Hackaday or larger tech nerd community.

Supercon is now in it’s eighth year. How long has Tod been going to Supercon?

I've been every year except for the very first one up in San Francisco and the offshoot ones they have in Europe. I'm a big fan of Hackaday, having been reading it since 2004. My wife Carlyn and I co-founded CrashSpace, a Los Angeles hackerspace that's going on its 15th year! (btw, if you're in SoCal on Dec 7, come by CrashSpace for its CRASH Art Show and 15 year celebration) When Supplyframe bought Hackaday, they invited us to come by to help bring about a "Hackaday Hackerspace" and that turned into the DesignLab, a much nicer and cleaner space than most hackerspaces and much more usable for conferences. And I did a DesignLab Residency in 2017. Suffice to say, I'm a big fan of Hackaday and the DesignLab, and my thoughts are colored by now 20 years of being in the Hackaday community.

What’s the biggest thing that’s changed over that period?

It's surprisingly consistent. That's partly due to the consistency of venue. I think it's more crowded now than when it started. The consistency is strange: I see friends there I only really interact with online because they live in New England or Germany and we're able to pick up right where we left off, like it's just another day and not been a whole year. As for conference content, they've struggled with the perennial tech world issue of having a bunch of old white guys like me on stage, but this year it feels like they've made strides towards fixing that. I really look forward to Supercon every year and I'm glad they're working on making it more inclusive.

About Supercon badges

Generally Supercon conference badges are PCBs with complex circuitry that is both visually interesting and presents a sort of puzzle to the attendees. For some, the conference is an entire weekend of hacking the badge: figuring it out and making it do something cool.

And almost none of them have spaces to write your name. We've evolved beyond badges being used for name identification.

Past badges have ranged from an FPGA that ran Linux, a 4-bit "retro" computer you programmed with switches, a virtual vectorscope, and a mesh networking chat keyboard.

Another aspect to these electronic badges has been add-ons, little extra circuits that just light up or add some functionality to the badge. I personally think they started as a way to identify the badge holder as the badges themselves lost their ability to do this.

For the last six years or so these add-ons have been codified into a standard called "SAO" -- simple add-on (originally shitty add-on by Brian Benchoff). It's a 6-pin connector that provides power, an I2C bus, and two pins of GPIO for whatever you want. Most add-ons just use power and light up in some cool way.

These SAO badge add-ons are generally pretty small: about 2" on a side. The size and format allows for easy exploration of PCB art. A lot of experimenting with PCB colors and LED back lighting happens here.

So given the rise of SAOs, this year's badge is primarily a platform to show off SAOs. It has six SAO sockets on the front and a PicoW and batteries on the back. It also came with a small collection of starter SAOs to display immediately.

But the real fun came as people gave out and traded SAOs all during the conference.

Tod's 2024 Simple Add On

Majenta and Giovanni of the Supplyframe DesignLab (where SuperCon is held) contacted me in August, asking if I wanted make an SAO based off off my touchwheel0 experiments. It was a fun and quick process to scale down my Pico-based experiments to an ATtiny controller appropriate for an SAO. Thankfully, my Arduino touch library worked well enough and the Arduino core for the ATtiny816 works great that I was able to get a prototype designed, routed, and fabbed in a week. Then we went through a couple design iterations to find the right combination of LED and chip packages to make it producable at scale.

The result is the TouchwheelSAO board that everyone got with their badge. In addition to being an ipod-like touch wheel, it's also got three addressable RGB LED backlights to indicate touch position. Simple but seems to work! The I2C protocol I desgined for it was meant to be as easy-as-possible for people to get touch data out of it or control its LEDs. Judging from the lack of questions about it and the many hacks people had that used it, I think it succeeded in that regard.

I wasn't convinced the captouch stuff would work reliably in the wild, battery-powered environment of the conference. But it seeme to! In retrospect, I think using four interleaved touch pads instead of my usual three would've been better. It would've let us downgrade to a simple D-Pad if the analog touch angle calculations wasn't working reliably.

Giving Robotic Friends a Voice: Jorvon Moss & Shawn Hymel by Jorvon Moss (Odd-Jayy) & Shawn Hymel (Paul #1)

Jorvon has been working on robots for about 8 years.
His latest robot, is Digit. Must be wearable, good and comfy, unique design, and the ability to be upgraded.
Neat design - he used magnets in the robot and metal plates in his clothes to anchor Digit to him
Wanted to integrate ChatGPT to be able to have a conversation with Digit, but that wouldn’t work as Jay needs to be mobile, like going to a conference like Supercon.
The Raspberry Pi didn’t work, as the Lama 3 8B model from Meta fit, but it was a 30-60 second wait for an answer when talking to the large language model
The Nvidia Jetson Orin Nano worked, but it’s much more expensive than a Pi at around $500
Shawn explains how the wake word detection works with the LLM in a docker container and the text to speech in a separate docker container
Working on prompt engineering - meaning it gives the robot personality. Odd Jay has used Southern and passive agressive, saying things like “Bless your heart” which is not used in a nice way down South.

The talk and the demo was great - check out the video to see Digit in action and it even tells a joke. Learn more at Shawn's GitHub repository

Circuit Graver by Zach Fredin (Tod #1)

post on Hackaday

Zach gave a talk on this, but on the DesignLab stage. The DesignLab videos aren't streamed immediately to Youtube. We'll have to wait for Hackaday to upload it. It's worth a watch!

The Circuit Graver is essentially a computer-controlled drag-knife that can cut through copper-clad boards. The result is a lot like CNC milled PCBs, but it's much faster. And the cutting bit is not wee little drill bit that snaps when you look at it wrong.

Zach is also a friend. I've been seeing him make crazy circuits with just carving copper boards for many years. It's neat to see him extend this to computer control.

Solving the Last Mile With 3D-printed Packaging by Christina Cyr (Paul #2)

Christina Cyr - Solving the Last Mile With 3D-printed Packaging

Christina Cyr is the CEO of dTOOR and The Cyrcle Phone
Electrical engineer
Dunnage - the packaging inside the box
Tissue paper
Plastic bag
Peanuts
Bubble wrap
Molded / folder cardboard (in most smartphones today)
What can small manufacturers do?
Handmade cardboard molds
PCB, Enclosure, Packaging
Could the enclosure and packaging made out of the same material and is recycled / biodegradable
Ended up going with biodegradable corn / rice based PLA material for 3D printers
Challenges
Typical CAD software not used for designing packaging, but there are two specialty programs that do CAD design for packaging (ArtiosCAD and Kasemake)
Can’t just scale your product design to allow for packaging
Soft TPU is a pain
- Can’t print soft TPU in the Bambu or Prusa, but could print on a Creality printer
Lesson learned: Could have shipped with bubble wrap that is made from 80% recycled nylon and is stronger than regular bubble wrap

In Living Color: A New World of Full-Color PCBs" by Joe Long. (Tod #2)

Joe runs HackerBoxes, a monthly subscription service for cool PCB-based nerd toys. He's been doing PCB art for a while and jumped in early on the full-color PCB services that both JLCPCB and PCBWay offer. He went into his past attempts with doing full color on PCBS (stickers!) and his experiences with these new services.

Microcontrollers Are Just Radios in Disguise - Charles Lohr

Hackaday Supercon 2024 - Microcontrollers Are Just Radios in Disguise - Charles Lohr

In his intro, Charles shares he loves exploring what microcontrollers are capable of without wads of abstractions.

Charles has a few rules to his hardware hacking, but the one to take away is using a microcontroller to do what the original chip designers expect to be impossible.
Fan of the ATTiny85
Used it to transmit radio signals using GPIO
Toolbox - cannot use the built-in radios, like wifi on the ESP8266
Digitally controlled oscillator
Frequency Modulation (FM)
Dithering
PLL for Frequency Multiplication
PWM for output
Harmonic output
Wants to transmit NTSC video using these tools - much more complicated than sending FM
Moving to the ESP 8266
No PWM is the challenge, but does have I2S, used for audio
Can play back bitstreams and broacasting NTSC black and white video just worked
Challenge was to get color video working and using a simulator, figured out the NTSC harmonics and reflections that allowed it
Could they transmit LoRa on a microcontroller without a LoRa radio? Lora stands for long range - it sends radio packets at 900MHz
The ESP32-S2 didn’t work, but 2 chips di: the ch32v203 and esp8266 (not using the radio) using PWM
Wrote his own LoRa stack to work with LoRaWAN
Could send packets up to 1/2 a kilometer away
Eventually did get the ESP32-S2 working over 2.5 kilometers away
Transmitting is the “easy” part, could he figure out receiving and figure out the timing?
Used the ch32v003 at $0.10 each
Figured it out, and had to figure out why is it working and why is it so weak
Could pick up the signal at 500 feet without any radio hardware
Ended up using the ch32v203 to create the receiver as it was slightly faster and needed for tuning the AM frequency

Favorite SAO(s) (Paul)

A few of Paul’s favorites: * Etch SAO (tiny Etch-a-sketch) * SAO Digital Multimeter (Best overall) by Thomas Plummer * Instant Arcade’s Pac-man SAO (ineligible due to using last years badge) (SMD challenge winner) * Steven, a Simon clone - which uses Todbot’s SAO! * Wish I could have seen: * Turntable SAO * Marvel X-Men SAO

Favorite SAO(s) (Tod)

First, check out all the amazing SAO contest submissions and this hackaday.io SAO list by Dave Darko

The winner of the Hackaday SAO contest really won me over too. It's a full digital multimeter by Thomas Flummer. It looks like a tiny Fluke meter. It's got probes! And useful functions like I2C bus handling. And it's code is written in CircuitPython! It looks very well engineered and I think will be mass-produced by Hackaday for future Hackaday conferences.

Another one I really liked was the Record Scratch SAO by Simen E. Sørensen. It looks like a record, but is a captouch wheel kinda like my SAO. When you move your finger across it, it makes record scratch noises and plays beats! It does this because it's a full RP2040 system with enough flash memory to store a sample and some clever code to scrub around in it.

A whole other category for me is favorite SAO that were given to me. Of these, my favorite is the TARS SAO by Dave Darko. Dave is a very prolific SAO maker and you can learn a lot by looking at his designs. The TARS SAO has a full-color TFT display, a speaker, and its face is 6 touch pads. And its driven by a Waveshare RP2040 Zero board. He's got several apps for it and it's really fun to play with.

SAO collection courtesy Dave Darko

2024-12-022026-01-03

The Bootloader

Episode 32 - Wave of Mutilation

Welcome to the show

Listen to the podcast

Show Notes

00:20 Open BoardsGuide (Paul #1)

4:49 BumpMesh.com (Tod #1)

8:10 Parachord Music Player (Paul #2)

11:51 SerialPlotster (Tod #2)

18:19 picoCAD 2 (Paul #3)

21:13 WaveOverhangs (Tod #3)

Episode 31 - Help I'm Alive

Welcome to the show

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Show Notes

00:15 BambuHelper (Tod #1)

BambuHelper Links

5:56 OpenScan (Paul #1)

8:53 Xteink X4 eink ebook reader (Tod #2)

Links about the Xteink X4

12:58 Project Aura (Paul #2)

17:06 Baochip-1x open source microcontroller (Tod #3)

Links about the Baochip

21:51 OpenCode (Paul #3)

Episode 30 - Spin the Black Circle

Welcome to the show

Listen to the podcast

Show Notes

00:19 Statimatic STM-01 Automatic Turntable (Paul #1)

5:00 MicroPythonOS and WaveShare ESP32-S3-Touch-LCD-2 (Tod #1)

10:16 3D Printing News Roundup (Paul #2)

14:37 Teenage Engineering Ting EP-2350 (Micropython-based product) (Tod #2)

20:48 Game Controllers (Paul #3)

24:46 LOOKMUMNOCOMPUTER is going to Eurovision 2026 (Tod #3)

Episode 29 - Kick Out the Jams

Welcome to the show

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Show Notes

Flock camera hacking w/ Benn Jordan (Tod #1)

Naya Connect Modular Keyboard Kickstarter (Paul #1)

ESP32-C5 now in Xiao form (Tod #2)

Let's chat about the Adafruit Fruit Jam (Paul #2)

Using Native TensorFlow & PyTorch Neural Networks in CircuitPython (Tod #3)

Washington State's proposed 3D printing bills (Paul #3)

Wrap-up

Episode 28 - Games Without Frontiers

Welcome to the show

Listen to the podcast

Show Notes

Building my own Steam Machine (Paul #1)

Learn Sewing Machines, they're cool! (Tod #1)

CAD Round-up (Paul #2)

Learn Analog Electronics by Building Synths (Tod #2)

The Indie Beat FM and Television (Paul #3)

'act' to run Github Actions locally (Tod #3)

Episode 1 - Rock Stars are Just Like Us

Welcome

Show Notes

FullControl.xyz (Tod #1) 0:23

tio (Paul #1) 2:11

Belay (Tod #2) 4:14

Rivers Cuomo (Paul #2) 6:36

CircuitPython Camera Support (Tod #3) 8:57

Bambu Labs X1 Carbon 3D Printer Review (Paul #3) 11:36

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Episode 2 - M is for Makers, Music, and Machine Learning

Welcome

Show Notes

Episode Intro

PixelBlaze expression language (Tod #1) 1:45

Whisper OpenAI (Paul #1) 5:50

Music generation in the browser (Tod #2) 11:03

PolyKeyboard (Paul #2) 16:41

Samplebrain by Aphex Twin & Dave Griffiths (Tod #3) 21:27

Kevin McAleer and the Pikon (Paul #3) 23:48

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Episode 3 - The Middle is a Pumpkin

Welcome

Show Notes

Episode Intro

`jpegio` and the Memento Camera

`paralleldisplaybus`