The Zero is a simple and powerful 32-bit extension of the platform established by the UNO.The board is powered by Atmel’s SAMD21 MCU, which features a 32-bit ARM Cortex M0 core. One of its most important features is Atmel’s Embedded Debugger (EDBG), which provides a full debug interface without the need for additional hardware.

SPECIFICATIONS :

Microcontroller ATSAMD21G18, 32-Bit ARM Cortex M0
Operating Voltage 3.3V
Digital I/O Pins 20
PWM Pins 3, 4, 5, 6, 8, 9, 10, 11, 12, 13
UART 2 (Native and Programming)
Analog Input Pins 6, 12-bit ADC channels
Analog Output Pins 1, 10-bit DAC
External Interrupts All pins except pin 4
DC Current per I/O Pin 7 mA
Flash Memory 256 KB
SRAM 32 KB
EEPROM None. See documentation
LED_BUILTIN 13
Clock Speed 48 MHz
Length 68 mm
Width 53 mm
Weight 12 gr.