Microcontroller development board: USB (Micro-B/USB-C) for power/programming/serial, 0.1in or castellated GPIO headers exposing UART/SPI/I2C/PWM/ADC, Qwiic/STEMMA/Grove (JST-SH/JST-PH) I2C ports, JST battery input, optional SWD/JTAG debug and antenna/u.FL.