Then there’s a host of input and output options, including three analogue inputs (connected to Pico’s ADC channels) for connecting external sensors, a ZIP socket to add more LEDs, a three-pin servo connector, and two high-power outputs (screw terminals) with a max draw of 1 A. In addition, there are solder pads for 3V3 power, GND, digital pins, SPI, and UART.

Power-wise, there’s a handy switch in one corner and a 3 × AA battery holder on the rear. There’s even a 5 V input if you want to charge up the batteries with a solar panel.

What a gas

The key feature of the board is its BME688 sensor, located in one corner. As well as measuring temperature, humidity, and atmospheric pressure (as on a BME680), it features an AI-enhanced gas sensor that detects volatile compounds and gases to determine IAQ (Index of Air Quality) and estimated CO2 levels. It takes five minutes to calculate the baseline for the gas sensor when first used, but this a one-off process and ensures greater accuracy for future readings.

All in all, this is a well-thought-out board backed up by some top-notch documentation and software. Multiple online tutorials cover its various functions in detail, including data logging and analogue input/output control. The GitHub repo includes a comprehensive MicroPython library for the board and numerous code examples to try out.

Verdict

9/10

A fully-featured Pico add-on with plentiful input/output options, offering a host of possibilities for projects. Excellent documentation too.

Specs

Sensor: BME688 – temperature, humidity, pressure, gases

Connectors: Dual female header for Pico, 3 × ADC inputs, ZIP LED socket, servo output, 2 × high-power outputs, 5 V power input, plus extra solder pads

Features: 128×64 monochrome OLED, 2 × push-buttons, piezo buzzer, 3 × ZIP (WS2812B) RGB LEDs, 3 × AA battery holder

Dimensions: 74×72×27.1 mm