CrumbX128A3 V1.2 is a versatile and very compact/small (just 40x30mm size!) microcontroller module with the ATxmega128A3U microcontroller, 3.3V LDO voltage regulator, CP2102 USB UART converter, RS485 transceiver and a micro-sd-card header/slot. All microcontroller signals are available on pin headers. A selectable XTAL crystal is included.
The module is shipped without preassembled pin headers, since everybody has different preferences or requirements. A Connector Kit with a suitable set of pin headers and receptacles can be ordered optionally.
You can find further information in the documents tab.