The Seeedstudio XIAO SAMD21 is a small board with 14 pins that is highly compatible with Arduino’s SAMD21 based microcontroller boards (Nano 33 IoT, Zero, and the MKR series of boards). It contains only the microcontroller, a crystal oscillator (which the Nano 33 IoT does not have), voltage regulator and a “modern” USB-C connector for …