Olimex has released the PICO-EVB, a compact open-source automation board that pairs with any Raspberry Pi Pico or compatible microcontroller to control mains-voltage loads and read high-voltage signals. The full KiCad hardware design files are published on GitHub under the CERN Open Hardware Licence Version 2 - Strongly Reciprocal, alongside ready-to-use Arduino, MicroPython, and ESPHome firmware, making it one of the more accessible entry points for DIY home and industrial automation projects.
The board packs four 15A/240V AC relays and four optoisolated inputs rated for 3.3 to 30V DC or 110 to 220V AC onto a 10 x 7 cm (3.9 x 2.8 in) footprint. Two 20-pin headers accept a Raspberry Pi Pico, Pico 2, Pico W, Pico 2 W, or Olimex's own RP2040-PICO30. A UEXT connector breaks out I2C, UART, and SPI for daisy-chaining sensors or displays, and USB-C handles both power and programming. The industrial temperature range of -45°C to +85°C (-49°F to 185°F) suggests Olimex is targeting enclosure and workshop deployments, not just bench prototyping.
The software side is where the PICO-EVB gets particularly interesting for self-hosters. One of the included MicroPython samples spins up a web server on the Pico W for browser-based relay control, and the bundled ESPHome YAML configuration plugs the board directly into Home Assistant. ESPHome's RP2040 and RP2350 platform support is now mature, with over 140 boards from the arduino-pico framework compatible, so the PICO-EVB slots into an established ecosystem rather than requiring bespoke integration.
The PICO-EVB is available now from Olimex for $17 (€15). A Pico board is not included.
