Adafruit Feather M0 Express

At the heart of the Feather M0 is the robust ATSAMD21G18 ARM Cortex M0+ processor, running at a brisk 48 MHz with 3.3V logic. This powerhouse offers 256KB of FLASH and 32KB of RAM, providing ample space for complex projects.

The built-in USB enables seamless USB-to-Serial programming and debugging without an FTDI-like chip. The board is geared for easy use with CircuitPython but supports Arduino IDE and more, thanks to its UF2 bootloader, which simplifies coding by acting like a USB storage device.

It measures a compact 2.0" x 0.9" x 0.28" and weighs a mere 5 grams, making it ideal for portable applications. With 20 GPIO pins, numerous input and output options, and built-in hardware support for Serial, I2C, and SPI, versatility is at your fingertips. The built-in 100mA LiPo charger and pin #13 LED add extra convenience for your projects.

For enhanced functionality, choose the Feather M0 Express. It adds a Mini NeoPixel, 2 MB SPI Flash storage, and prototyping space, acting like a micro hard drive. Flash storage can also be used for datalogging or file access over USB, thanks to our helper program.

Although it's our pioneer for CircuitPython, we now recommend the Feather M4 for a faster, more expansive experience. The Feather M0 still comes fully assembled and tested, making it an excellent choice for makers and enthusiasts looking to explore electronics with ease. Just remember, a LiPo battery and USB cable are necessary but available separately. All these features ensure that this compact board punches well above its weight.