We finally got our hands on the first of SparkFun’s RP2040 line of boards. The $10 SparkFun Pro Micro RP2040 is the cheapest model on offer and follows a classic design similar to an Arduino Nano board layout that is at home in a breadboard and embedded in your projects. It also provides us with a considered selection of GPIO pins and a Qwiic connector for compatible expansion cards.
SparkFun’s range of RP2040 boards is varied, but the Pro Micro RP2040 is the most typical of the bunch, due to its reasonable cost and familiar form factor. The other two are the Thing Plus RP2040 which is designed in a similar layout to Adafruit’s Feather RP2040 but with an additional 16MB micro SD card with flash storage. The latest RP2040 board is the MicroMod RP2040 processor, an M.2 board featuring the RP2040 for use in a range of carrier boards.
SparkFun’s Pro Micro RP2040 seems to be the ideal form factor for those who need lots of GPIO pins, jagged edges and a Qwiic connector. We tested the latest board RP2040 on our workbench and were pleasantly surprised by its versatility.
SparkFun Pro Micro RP2040 Hardware Specifications
|RP2040 SoC||ARM Cortex M0+ operates at a maximum of 133 Mhz|
|Flash storage||16 MB external flash memory|
|GPIO||20 GPIO pins with the following functionality:|
|10 x PWM outputs 10 x Digital I/O, 4 x Analog 12-bit ADC, 1 x I2C (Qwiic), SPI, 2 x UART, Programmable IO, 1 x WS2812 / NeoPixel|
|USB port||USB C|
|Dimensions||1.3 x 0.7 inches (33 x 17.8mm)|
Design of the SparkFun Pro Micro RP2040
Be almost as big as Adafruit’s ItsyBitsy RP2040SparkFun’s Pro Micro RP2040 features a well-known DIP package design, ideal for use in a breadboard, as well as at home when the surface mount is soldered in place using the castellations. Being a Pro Micro means the board matches the features of previous boards, mostly powered by Atmel chips and about double the price of the $10 RP2040.
The board’s bright red color sets it apart from a sea of black and green boards, and the screen-printed GPIO pin reference is clearly legible on both sides of the board. Power can be supplied from the USB C port, which is also used for programming the board, or we can use the RAW/+ pin and GND to supply 5V at 600mA, but be careful not to exceed these limits . On the other side of the board is a Qwiic connector that breaks the only I2C connection on the board.
Qwiic connectors are compatible with Adafruit’s Stemma QT format (see our story at: Qwiic vs Stemma vs Grove) and between the two sizes we have a wide choice of breakout boards, sensors and displays that can be easily and neatly connected to the port. If you want to use non-Qwiic boards, a Qwiic to jumper cable adapter is a cheap and easy alternative. Access to the UART, SPI pins is through the GPIO.
Using the SparkFun Pro Micro RP2040
Our tests were conducted with the latest versions of MicroPython and CircuitPython. For CircuitPython, we tested basic GPIO functionality with an LED and push button that worked without any issues. Just down the road we hooked up a WS2812/NeoPixel ring and installed the neopixel CircuitPython library and within minutes we had RGB lighting on our workbench.
We then connected an Adafruit MPR121 capacitive touch sensor via a Qwiic/Stema QT cable and soon we were able to use everyday objects as touch input. When we switched to MicroPython, we tested how to use I2C devices via the Qwiic connector. The first was an OLED screen that we coded to show a series of graphical demos and animations. The next test was a four-digit seven-segment display, a generic TM1637-powered board that uses header pins, forcing us to use a Qwiic-to-jumper cable adapter. The TM1637 is easy to work with thanks to a MicroPython library, we had a random four digit number generator and scrolling text.
SparkFun’s Pro Micro RP2040 combines the best features of two Adafruit RP2040 boards, the ItsyBitsy RP2040 and QT Py RP2040. Like Adafruit’s ItsyBitsy RP2040, SparkFun’s Pro Micro RP2030 offers a great selection of GPIO pins and a Qwiic/Stema QT connector and USB-C, just like the QT Py.
Use cases for the SparkFun Pro Micro RP2040
With serrated edges and a flat bottom, the SparkFun Pro Micro RP2040 is embedded in a home project like a breadboard. Embedding this board in your own circuit is trivial once you have the mechanical dimensions. So that that little RP2040 robot you wanted to build could become a reality with this board. Thanks to the Qwiic connector and 16 MB flash storage, the Pro Micro RP2040 can be used in data collection projects.
With a price tag of $10, the same as Adafruit’s ItsyBitsy RP2040, we prefer SparkFun’s Pro Micro RP2040 because it offers a lot of GPIO pins and a Qwiic/Stema QT connector in a relatively small package.
If you’re looking for a little more functionality from your RP2040 board and don’t mind the slightly higher price tag and larger form factor, the Adafruit Feather RP2040 is a great choice as it works with a huge ecosystem of expansion boards. If you need something smaller, the Adafruit QT Py RP2040 is the way to go. And of course the original Raspberry Pi Pico is the best value at just $4. However, if you want a nice mid-sized board with a lot of flexibility, the SparkFun Pro Micro RP2040 is the way to go.