Pro Micro RP2040
Sparkfun | $9.95 | sparkfun.com/rp2040
If you’re looking for the smallest RP2040 board, then this is it. SparkFun has squeezed and shrunk everything down to the footprint of its Qwiic Pro Micro range. However, unlike the original (which features a 16MHz, 8-bit microcontroller), this has all the processing power of the RP2040 to get your project running. Alongside this, there’s 16MB of RAM for your programs and data, which should be enough for almost all microcontroller applications. Despite its small size, it still breaks out 18 of the GPIOs, including four analogue inputs, and has a Qwiic connector for additional hardware. There’s a USB for data and power, a power LED, and a user-controlled RGB LED. There are reset and boot buttons, so you can program one of these without unplugging power (as is needed on Pico).
Adafruit Feather 2040
Adafruit | $9.95 | adafruit.com
You’re almost certainly going to want to plug some extra hardware into your microcontroller to build your projects. Whether that’s sensors, displays, or actuators, it’s this extra hardware that is usually the point of microcontroller projects. There are already some great accessories for Pico (see next page), but if you want to get access to a huge range of add-ons, the best solution is to jump right into one of the biggest microcontroller ecosystems around – Feather. Adafruit’s Feather 2040 has the standard pinout that lets you plug in almost any Feather add-on (or Wing as they are known). These are stackable, so you can add several of them if you need lots of features for your project.
21 GPIOs are broken out, and there’s also on-board LiPo battery charging if you need your project to be portable, and a STEMMA QT connector for adding even more hardware. There’s 4MB of flash for storing your data and programs, and like the Mini, there are both reset and boot buttons. All this means that the board is slightly wider than Pico (one row on a breadboard).
The Feather 2040 comes set up and ready to run CircuitPython. This is a little different to MicroPython on Pico. CircuitPython includes excellent support for Adafruit (and other) hardware.
Sparkfun | $11.95 | sparkfun.com
We looked at the MicroMod system in issue 38. It allows you to quickly and easily slot a microcontroller module into a carrier board. These modules are stripped right back to just the bare essentials, so they’re tiny, and the M.2 mounting means they are secure and don’t add any height to the carrier board. This can mean you have a bit less flexibility than with some other add-on systems, but if there’s a carrier board that suits your needs, it can be a compact and robust solution. If you’re looking for a large Arduino Uno-like board with an RP2040 at its heart, there’s the ATP carrier. If you’re looking for a board with input and display, there’s the aptly named Input and Display carrier. There are also data logging and machine learning carrier boards. As with the Pro Micro, there’s also 16MB of flash memory to store programs and data, but other than this, all features are on the carrier boards rather than the processor boards.
Pimoroni | £58.50 | pimoroni.com
Unlike the other boards we’ve looked at here, Pico System isn’t intended to be a general-purpose board; it’s designed with one (very obvious) use in mind: RP2040 makes a great gaming platform. PIO with DMA means that it can output video data very quickly with little CPU overhead, and having two cores and plenty of memory means that there’s loads of scope for doing all the processing that games demand. Add to this some beautiful design work, and you get a fantastic handheld console which we’re looking forward to playing with more in the coming months.
Of course, you don't have to wait for these to arrive. You can get started with RP2040 and Raspberry Pi Pico right now. We'll send you a Pico for free if you take out a HackSpace magazine subscription. Head here to see our offers (from £5).