Adafruit Feather M0 WiFi (ATSAMD21 + ATWINC1500)

Overview

The Adafruit Feather M0 WiFi pairs the ATSAMD21G18 ARM Cortex-M0+ microcontroller with Atmel's ATWINC1500 WiFi module on the standard Feather form factor. The ATWINC1500 is a FCC-certified 802.11b/g/n module that handles all RF operations independently, supports WEP/WPA/WPA2 security, and even offers SSL/TLS 1.2 for secure connections — all controlled via SPI from the SAMD21.

Running at 48 MHz with 256KB of flash and 32KB of SRAM, the SAMD21 brings significantly more compute and memory than ATmega-based WiFi boards. It also provides native USB support — meaning it can enumerate as a keyboard, mouse, MIDI device, or serial port without any additional chip.

The board integrates a 200mA LiPo charger, enabling fully wireless battery-powered operation. A built-in regulator provides 600mA at 3.3V, sufficient to power the WiFi module's 300mA peak draw during transmission bursts. The 10 analog inputs (12-bit ADC), 8 PWM channels, and hardware SPI/I2C/UART make it a capable platform for sensor-connected WiFi nodes.

With Arduino IDE support via the Adafruit SAMD board package and the Adafruit_WINC1500 library, this board makes building WiFi-connected devices straightforward while retaining the flexibility of a full-featured development board.