This repo is still under construction, all related files will be released very soon!
PICO: a tiny but powerful Arduino-compatible development board built for makers who don't want to compromise. Measuring just 17.78 × 15.24 mm (0.7" × 0.6"), PICO is small enough to disappear into wearables, drones, and pocket-sized prototypes, yet packs enough capability to drive serious projects.
At its core, PICO runs the proven ATmega32U4 microcontroller and exposes 14 GPIOs, giving you plenty of room to connect sensors, displays, motors, and just about anything else you can dream up. A built-in WS2812 addressable RGB LED on pin D5 adds a splash of color for status indication or pure fun. The board is fully breadboard compatible, so you can prototype quickly without extra adapters.
PICO is open source by design. All schematics, PCB layouts, and source files are available in this repository, so you're free to learn from it, modify it, or build on top of it.
- Ultra-compact: 17.78 × 15.24 mm (0.7" × 0.6") footprint
- ATmega32U4: microcontroller with native USB
- 14 GPIOs: including PWM, ADC, I²C, SPI, and UART
- Built-in WS2812 RGB LED: (addressable, on pin D5)
- Breadboard friendly: castellated pins
- Multiple power options: USB and VIN
- Arduino IDE compatible: program it like any Arduino Leonardo
- Fully open source: schematics, PCB, and code freely available
| Category | Specification |
|---|---|
| Microcontroller | ATmega32U4 |
| Architecture | 8-bit AVR |
| Clock Speed | 16 MHz |
| Flash Memory | 32 KB (4 KB used by bootloader) |
| SRAM | 2.5 KB |
| EEPROM | 1 KB |
| GPIO Pins | 14 |
| PWM Channels | 3 (D4 D10 D11) |
| Analog Inputs | 5 (D4 D12 A0 A1 A2) |
| Communication | USB, I²C, SPI, UART |
| Operating Voltage | 5 V |
| Input Voltage (VIN) | 7V~15V or power from USB port |
| DC Current per I/O Pin | 40mA |
| Onboard LED | 1× WS2812 addressable RGB (1 × 1 mm) on D5 |
| USB Connector | USB Type-C (Use USB Typ-A to Type-C cable, I forgot to add the 5.1K resistord on CC pins 🐸) |
| Dimensions | 17.78 × 15.24 mm (0.7" × 0.6") |
| Weight | ~1.1 g |
| Pin | Type | Alternate Functions | Notes |
|---|---|---|---|
| Vin | Power (input) | — | 7–15 V external supply |
| +5V | Power (output) | — | Regulated 5 V output |
| GND | Ground | — | Common ground |
| RST | Reset | — | Active low; pull to GND to reset |
| SCK | Digital | D15, SPI Clock | SPI bus |
| MOSI | Digital | D16, SPI Master-Out | SPI bus |
| MISO | Digital | D17, SPI Master-In | SPI bus |
| D4 | Digital | A6 (Analog In) | ADC capable |
| D3 ~ | Digital | PWM | PWM output |
| D2 | Digital | — | General-purpose I/O |
| D0 | Digital | RX (UART) | Serial receive |
| D1 | Digital | TX (UART) | Serial transmit |
| A0 | Analog | Digital I/O | ADC input |
| A1 | Analog | Digital I/O | ADC input |
| A2 | Analog | Digital I/O | ADC input |
| D9 ~ | Digital | PWM | PWM output |
| D10 ~ | Digital | PWM | PWM output |
| D11 ~ | Digital | PWM | PWM output |
| D5 | Digital | WS2812 RGB LED (onboard) | Connected to onboard RGB LED |
Download and install the latest Arduino IDE (version 2.x recommended).
In Arduino IDE, go to Tools → Board → Board Manager and select Arduino Leonardo, PICO is fully Leonardo-compatible.
Plug PICO into your computer using a USB cable (Use USB Typ-A to Type-C cable, I forgot to add the 5.1K resistord on CC pins 🐸). The onboard RGB LED will light up briefly to confirm power.
If you prefer FastLED over Adafruit NeoPixel, PICO works just as well with it. FastLED is a powerful, performance-focused library with built-in color palettes, HSV support, and smooth animation helpers.
In the Arduino IDE, go to Sketch → Include Library → Manage Libraries…, search for FastLED, and click Install.
Blink LED using FastLED library (Example from the library itself, don't forget to change the Data pin to D5):
#include <Arduino.h>
#include <FastLED.h>
// How many leds do we have?
#define NUM_LEDS 1
#define DATA_PIN 5 // LED pin
#define CLOCK_PIN 13
// Define the array of leds
CRGB leds[NUM_LEDS];
void setup() {
//Serial.begin(9600);
//Serial.println("BLINK setup starting");
FastLED.addLeds<NEOPIXEL, DATA_PIN>(leds, NUM_LEDS);
}
void loop() {
//Serial.println("BLINK");
// Turn the LED on, then pause
leds[0] = CRGB::Red;
FastLED.show();
delay(500);
// Now turn the LED off, then pause
leds[0] = CRGB::Black;
FastLED.show();
delay(500);
}Click Upload — and you're up and running.
All hardware design files are open and available in the /hardware folder:
- Schematics —
hardware/PICO V1.0.pdf.pdf - PCB Files —
hardware/pcb/(Eagle source files)
Designed in Eagle. Feel free to fork and remix.
PICO features a single WS2812B addressable RGB LED connected to digital pin D5. Use the Adafruit NeoPixel or FastLED libraries to control it.
See examples/01_Blink_RGB for a minimal working sketch.
PICO can be powered in two ways:
| Source | Voltage | Notes |
|---|---|---|
| USB | 5 V | Plug-and-play for programming and power |
| VIN pin | 7V~15V | For battery or external supply |
⚠️ Do not apply power to USB and VIN simultaneously unless you understand the implications.
Got questions, ideas, or want to share what you built with PICO?
- Discussions: GitHub Discussions
- Issues / Bugs: Open an issue
- Website: vcclabs.com
- Email: thevcclabs@gmail.com
Contributions are welcome! Whether it's a bug fix, a new example sketch, or documentation improvements, feel free to open a pull request.
- Software & examples are licensed under the MIT License.
- Hardware design files are licensed under the Creative Commons Attribution 4.0 International License (CC BY 4.0).
You are free to use, modify, and distribute - including for commercial purposes - provided you credit Vcc Labs as the original creator.
https://github.com/fastled/fastled
PICO was made possible thanks to:
- The 78 backers who supported us on Kickstarter 🚀
- The open-source hardware community
- The Arduino, Sparkfun, FastLED, and Adafruit teams for their incredible libraries and tools
Built with ❤️ by Vcc Labs