This is a list of RP2040-based microcontroller unit (MCU) boards that can be used in keyboard projects. Much of this data comes from Keyboard Builders’ Digest as well as r/MechanicalKeyboards. Another list of RP2040 boards can be found on the downloads page of the CircuitPython project when filtering by “Raspberrypi”.
For wireless builds, see this list of NRF52840-based boards.
| Name | Open | Vendor | Colour | Cast. | Flash | Extra GPIO | USB Port | USB Brk. Out | Power LED | User LED | 1-Btn. Boot | Buttons | VBus Det. | Price | Ship. | Total |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 0xB2 - splinky | Yes | Bastard Keyboards | Black | No | ≤16MB | 5 bottom | Mid | No | No | Yes | No | 2 (front) | GPIO19 | (€24) | ? | ? |
| 0xCB-Helios | Yes | KeebSupply | Black | Yes | 16MB | 5 bottom, 2 top, 1 inset (5V) | Mid | Inset | Red (optional) | Blue | Yes | 1 (front) | GPIO19 | €16 | EU | ? |
| Keycapsss | €16 | €9 | €25 | |||||||||||||
| Ringer Keys | $20 | $5 | $25 | |||||||||||||
| RNDKBD | $18 | $6 | $24 | |||||||||||||
| Bit-C PRO | No | nullbits | Black, White | No | 4MB | 5 bottom | Top | No | Uses user LEDs | 3 — RG&B | Yes | 0 | No | $20 | $0 | $20 |
| Blok | No | Boardsource | Black | Yes | 16MB | 0; see note (1) below | Mid | No | Purple | RGB | No | 2 (side) | No | $14 | $5 | $19 |
| Elite-Pi | No | 1upkeyboards | Blue | Yes | 2MB | 5 bottom, 2 pads | Mid | Pads | No | No | No | 2 (front) | No | $17 | $0 | $17 |
| Keebio | $13 | $5 | $18 | |||||||||||||
| Frood RP2040 | Yes | 42.Keebs | Various | No | 4MB | 5 | Mid | Top | No | Orange | No | 2 (front) | GPIO19 | €11 | €5 | €16 |
| KB2040 Kee Boar | No | Adafruit | Black | Yes | 8MB | 2 Qwiic; see note (2) below | Top | Top | Green | RGB | No | 2 (front) | No | $9 | $4 | $13 |
| key micro RP | No | BOOTH | Black | No | 4MB | 0 | Mid | Pads | No | No | No | 2 (side) | No | ¥2700 | ? | ? |
| Laitris | No | splitkb | Black | Yes | 16MB | 5 bottom; see note (3) below | Mid | Pads | Yes (back, GPIO24) | RGB | No | 1 (back) | No | €15 | €18 | €33 |
| Pro Micro RP2040 | Yes | SparkFun | Red | Yes | 16MB | 2 Qwiic | Top | Pads | Red | RGB | No | 2 (front) | No | $11 | $11 | $22 |
| RP2040 Pro Micro | No | Tenstar Robot⁴ | Black | No | 4/16MB | 5 bottom, 3 inset | Mid | No | No | RGB | No | 2 (front) | No | $3 | $2 | $5 |
| Sea-Picro EXT | Yes | beekeeb | Black | No | 16MB | 5 bottom, 1 inset (5V) | Mid | Top | No | No | Yes | 0 | GPIO19 | $10 | $8 | $18 |
| Custom KBD | Black | Yes | $17 | $15 | $32 | |||||||||||
| Sea-Picro RST | Yes | None | Black | No | 16MB | 0 | Mid | Top | No | RGB | Yes | 1 (front) | GPIO19 | |||
| svlinky | Yes | fingerpunch | Black | No | 8MB | 9 VIK | Mid | No | No | Yes | No | 0 | GPIO19 | $15 | $10 | $25 |
- Open — indicates whether the schematic and/or PCB design is openly documented (if not actually released under an open source license), and links to that documentation if available.
- Cast. — indicates whether the PCB is castellated or not.
- Extra GPIO — indicates the number and location of any I/O pins beyond the usual 18 for a
Pro Micro:
- Bottom — located on the “bottom” row of the PCB (if the USB port is the “top”)
- Top — located on either side of the USB port above the usual Pro Micro pins
- Inset — located inside the usual pins
- Pads — I/O is accessed via solder pads on the reverse of the PCB rather than through-hole connections
- Qwiic — SparkFun’s I²C interconnect system that uses a four-pin JST connector to provide 3.3V, GND and two I/O
- VIK — an interconnect system that uses a twelve-pin FPC connector to provide 5V, 3.3V, GND and 9 I/O
- 5V — indicates that the output signal is at 5V rather that 3.3V, which means that RGB LEDs can be driven at spec
- USB Port — all boards are USB C unless noted, a mid-mount board will typically result in an overall thickness of 3.2mm (the thickness of a USB C port), while a top-mount board will be 3.2mm plus the thickness of the PCB (typically 1.6mm).
- USB Brk. Out — indicates whether there is access to the USB data (i.e., whether a USB breakout board be used with this controller), and the type and approximate location of the access points. Locations are as Extra GPIO pins above.
- User LED — indicates whether there is an onboard LED (single colour or RGB) that can be accessed from firmware.
- 1-Btn. Boot — indicates whether the board has a combined reset and boot circuit (e.g., a short press will reset, while a long press will reboot). This means that only one on-board reset/boot button is required and off-board reset buttons can be used to go into boot-loader mode. (Once installed and appropriately configured, QMK can also trigger this via a double-tap of the reset button.)
- Buttons — indicates whether there are onboard reset/boot buttons and their general location:
- Front — the side of the board with most components and the USB port (if top mounted)
- Back — the other, usually unpopulated, side of the board
- Side — facing sideways from the board in the opposite direction to the USB port
- VBus Det. — indicates whether the board has a built-in VBUS detection circuit.
- Price — price of a single board before tax as of March 2024 in US dollars, euros or yen. To be used as a very rough guide to comparative cost.
- Ship. — lowest available cost as of March 2024 in US dollars or euros of shipping one board to the continental US (if possible). Populated with an appropriate country/region code if shipping area is limited.
- Total — Price plus Shipping. Again, to be used as a very rough guide to comparative cost for a single board. Does not include cost savings for multiple units, etc.
- Blok has GPIO 16 and 17 instead of 2 and 3 respectively.
- KB2040 has GPIO 10, 18 and 19 instead of 21, 22 and 23 respectively.
- Liatris runs at 3.6V for better 5V signal compatibility.
- The unbranded “RP2040 Pro Micro” is available at various AliExpress stores.
A small selection of RP2040-based controller boards that are not shaped like a Pro Micro.
| Name | Open | Vendor | Size (mm) | Colour | Cast. | Flash | Total GPIO | USB Port | USB Brk. Out | Power LED | User LED | 1-Btn. Boot | Buttons | VBus Det. | Price | Ship. | Total |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Raspberry Pi Pico | Yes | Various | 21.0×51.3 | Green | Yes | 2MB | 26 | Top, Micro! | Pads | No | RGB | No | 1 (front) | GPIO24 | $4 | $4 | $8 |
| RP2040-Zero | Part | WaveShare | 18.0×23.5 | Blue | Yes | 2MB | 20, 9 (pads) | Top | No | No | RGB | No | 2 (front) | No | $4 | $6 | $10 |
| Seeed XIAO RP2040 | Part | Seeed Studio | 17.5×21.0 | Black | Yes | 2MB | 11 | Top | No | Red | RGB, 3RG&B | No | 2 (front) | No | $5 | $7 | $12 |
| Stampy | No | Keebio | 57.3×21.5 | Purple | No | 2MB | 26 | Top | No | No | No | No | 1 (front) | GPIO9 | $13 | $6 | $19 |