SAM D21 Xplained Pro Evaluation Kit The SAM D21 Xplained Pro evaluation kit is ideal for evaluating and prototyping with the SAM D21 ARM® Cortex®-M0+ based microcontrollers. Xplained Pro Extension kits compatible with SAM D21 Xplained Pro can be purchased individually.<p>The ATSAMD21-XPRO evaluation kit does not include extension boards.<p>SAM D21 Xplained Pro supports many Xplained Pro extension kits, including I/O1 Xplained Pro, OLED1 Xplained Pro, QT1 Xplained Pro, and PROTO1 Xplained Pro.<p>To begin configuring software for your board, visit our web-based software configuration tool Atmel START.