Experimenting With MicroPython On The Bus Pirate 5

October 15, 2024 by 4 Comments

I recently got one of the new RP2040-based Bus Pirate 5 (BP5), a multi-purpose interface debugging and testing tool. Scanning the various such tools in my toolbox already: an Analog Discovery 2, a new Glasgow Interface Explorer, and a couple of pyboards, I realized they all had a Python or MicroPython user interface. A few people on the BP5 forums had tossed around the idea of MicroPython, and it just so happened that I was experimenting with building beta versions of MicroPython for a RP2350 board at the time. Naturally, I started wondering, “just how hard can it be to get MicroPython running on the BP5?”

The Lazy Approach

Rather than duplicating the BP5 firmware functionality, I decided to ignore it completely and go with existing MicroPython capabilities. I planned to just make a simple set of board definition files — perhaps Board Support Package (BSP) is a better term? I’ve done this a dozen times before for development and custom boards. Then write a collection of MicroPython modules to conform to the unique aspects in the BP5 hardware. As user [torwag] over on the Bus Pirate forums said back in March:

Micropython comes already with some modules and enough functions to get some stuff out-of-the-box working. E.g. the infamous version of “hello world” for microcontrollers aka led-blinking.

Continue reading “Experimenting With MicroPython On The Bus Pirate 5” →

Tulip Is A Micropython Synth Workstation, In An ESP32

August 8, 2024 by 6 Comments

We’re not sure exactly what Tulip is, because it’s so many things all at once. It’s a music-making environment that’s programmable in Python, runs on your big computer or on an ESP32-S3, and comes complete with some nice sounding synth engines, a sequencer, and a drum machine all built in. It’s like your dream late-1980s synthesizer workstation, but running on a dev board that you can get for a song.

And because Tulip is made of open-source software and hardware, you can extend the heck out of it. For instance, as demonstrated in this video by [Floyd Steinberg], you can turn it into a fully contained portable device by adding a touchscreen. That incarnation is available from Makerfabs, and it’s a bargain, especially considering that the developer [Brian Whitman] gets some of the proceeds. Or, because it’s written in portable Python, you can run it on your desktop computer for free.

The most interesting part of Tulip for us, as programmer-musicians, is that it boots up into a Micrypython REPL. This is a synth workstation with a command-line prompt as its primary interface. It has an always-running main loop, and you make music by writing functions that register as callbacks with the main loop. If you were fast, you could probably live-code up something pretty interesting. Or maybe it wants to be extended into a physical musical instrument by taking in triggers from the ESP32’s GPIOs? Oh, and did we mention it sends MIDI out just as happily as it takes it in? What can’t Tulip do?

We’ve seen some pretty neat minimalist music-making devices lately, but in a sense Tulip takes the cake: it’s essentially almost entirely software. The various hardware incarnations are just possibilities, and because it’s all open and extremely portable, you can freely choose among them. We really like the design and sound of the AMY software synthesizer engine that powers the Tulip, and we’re sure that more synthesizer models will be written for it. This is a music project that you want to keep your eyes on in the future.

Embedded Python: MicroPython Toolkits

August 5, 2024 by 22 Comments

Last time, I talked about how MicroPython is powerful and deserving of a place in your toolkit, and it made for a lively discussion. I’m glad to see that overall, MicroPython has indeed been getting the recognition it deserves – I’ve built a large number of wonderful projects with it, and so have people I’ve shown it to!

Sometimes I see newcomers dissatisfied with MicroPython, because the helper tools they initially pick don’t suit it well. For instance, they try and start out with a regular serial terminal application that doesn’t fit the MicroPython constraints, or a general IDE that requires a fair bit of clicking around every time you need to run your code. In particular, I’d make sure that you know your options no matter whether you prefer GUI or commandline – both have seriously nice tools for MicroPython use!

The main problem to be solved with MicroPython is that you have a single serial port that everything happens through – both file upload and also debugging. For ESP8266/32-based boards, it’s a physical serial port, and for chips like RP2040 and ESP32-S* where a hardware USB peripheral is available, it’s a virtual one – which makes things harder because the virtual port might get re-enumerated every now and then, possibly surprising your terminal application. If you want to upload a program of yours, you need to free up the serial port, and to see the program’s output, you will need to reopen that port immediately after – not a convenient thing to do if you’re using something like PuTTy.

So, using MicroPython-friendly software is a must for a comfortable hacking experience. What are your options? Continue reading “Embedded Python: MicroPython Toolkits” →

Embedded Python: MicroPython Is Amazing

July 11, 2024 by 105 Comments

In case you haven’t heard, about a month ago MicroPython has celebrated its 11th birthday. I was lucky that I was able to start hacking with it soon after pyboards have shipped – the first tech talk I remember giving was about MicroPython, and that talk was how I got into the hackerspace I subsequently spent years in. Since then, MicroPython been a staple in my projects, workshops, and hacking forays.

If you’re friends with Python or you’re willing to learn, you might just enjoy it a lot too. What’s more, MicroPython is an invaluable addition to a hacker’s toolkit, and I’d like to show you why. Continue reading “Embedded Python: MicroPython Is Amazing” →

A screenshot of the release page, showing the headline and a crop of the release notes

MicroPython 1.23 Brings Custom USB Devices, OpenAMP, Much More

June 2, 2024 by 25 Comments

MicroPython is a wonderful Python interpreter that runs on many higher-end microcontrollers, from ESP8266 to STM32 to the RP2040. MicroPython lets you build devices quickly, and its latest release, 1.23, brings a number of improvements you should be aware of.

The first one is custom USB device support, and it’s a big one. Do you want to build HID devices, or play with MIDI, or do multiple serial streams with help of PIO? Now MicroPython lets you easily create USB devices on a variety of levels, from friendly wrappers for creating HID or MIDI devices, to low-level hooks to let you define your own USB descriptors, with user-friendly libraries to help all the way through. Currently, SAMD and RP2040 ports are supported in this part of code, but you can expect more in the future.

Hooray to 10 years of MicroPython!

There’s more – support for OpenAMP, an inter-core communication protocol, has received a ton of improvements for systems where MicroPython reigns supreme on some of the CPU cores but also communicates with different systems on other cores. A number of improvements have made their way through the codebase, highlighting things we didn’t know MicroPython could do – for instance, did you know that there’s a WebAssembly port in the interpreter, letting you run MicroPython in your browser?

Well, it’s got a significant overhaul in this release, so there’s no better time to check it out than now! Library structure has been refactored to improve CPython compatibility, the RP2040 port receives a 10% performance boost thanks to core improvements, and touches upon areas like PIO and SPI interfaces.

We applaud all contributors involved on this release. MicroPython is now a decade old as of May 3rd, and it keeps trucking on, having firmly earned its place in the hacker ecosystem. If you’ve been playing with MicroPython, remember that there are multiple IDEs, graphics libraries, and you can bring your C code with you!

Accurate Cycle Counting On RP2040 MicroPython

August 26, 2023 by 14 Comments

The RP2040 is a gorgeous little chip with a well-defined datasheet and a fantastic price tag. Two SDKs are even offered: one based on C and the other MicroPython. More experienced MCU wranglers will likely reach for the C variant, but Python does bring a certain speed when banging out a quick project or proof of concept. Perhaps that’s why [Jeremy Bentham] ported his RP2040-based vehicle speedometer to MicroPython.

The two things that make that difficult are that MicroPython tries to be pretty generic, which means some hackery is needed to talk to the low-level hardware, and that MicroPython doesn’t have a reputation for accurate cycle counting. In this case, the low-level hardware is the PWM peripheral. He details the underlying mechanism in more detail in the C version. On the RP2040, the PWM module can count pulse edges on an input. However, you must start and stop it accurately to calculate the amount of time captured. From there, it’s just edges divided by time. For this, the DMA system is pulled in. A DMA request can be triggered once the PWM counter rolls over. The other PWM channel acts as a timer, and when the timer expires, the DMA request turns off the counter. This works great for fast signals but is inaccurate for slow signals (below 1kHz). So, a reciprocal or time-interval system is included, where the time between edges is captured instead of counting the number of edges in a period,

What’s interesting here is how the hardware details are wrapped neatly into pico_devices.py. The uctypes module from MicroPython allows access to MMIO devices such as DMA and PWM. The code is available on GitHub. Of course, [Jeremy] is no stranger to hacking around on the RP2040, as he has previously rolled his own WiFi driver for the Pico W.

MicroPython ESP32 IDE Makes Life Simpler

February 7, 2023 by 49 Comments

In theory, using MicroPython on the ESP32 is easy —  just flash an image and connect using a serial port. But that leaves a lot of things you still have to do. You need to move files between the two platforms. You’ll want to manage network configurations. You might want better editing and assistance, too. So there are a number of IDEs made to help you and one we recently noticed was MPY-Jama.

The IDE provides source code editing, of course. But it also allows you to do things like pull information about the network using a dashboard or connect to a WiFi network easily. You can even create your own AP with a simple interface.

Although the front part of the README mentions it is for Windows or Mac, if you scroll down you’ll find instructions for installing under Linux. The IDE is extensible using “Jama Funcs” and can handle the flashing operation from inside the IDE.

Of course, there is an IDE from Arduino (but not the Arduino IDE) that handles MicroPython. You can also find a rundown of several similar alternatives online.  If you need some inspiration for a MicroPython project, perhaps you’d like to play a game?