3727: Itsy Bitsy M0 Express - ATSAMD21 Cortex M0


What's smaller than a Feather but larger than a Trinket? It's an Adafruit ItsyBitsy M0 Express! Small, powerful, with a rockin' ATSAMD21 Cortex M0 processor running at 48 MHz - this microcontroller board is perfect when you want something very compact, but still with a bunch of pins.

ItsyBitsy M0 Express is only 1.4" long by 0.7" wide, but has 6 power pins, 23 digital GPIO pins (12 of which can be analog in, 1x analog out, and 13x PWM out). It's the same chip as the Arduino Zero and packs much of the same capability as an Adafruit Metro M0 Express or Feather M0 Express but really really small. So it's great once you've finished up a prototype on a Metro M0 or Feather M0, and want to make the project much smaller. It even comes with 2MB of SPI Flash built in, for data logging, file storage, or CircuitPython code.

The most exciting part of the ItsyBitsy M0 is that while you can use it with the Arduino IDE, we are shipping it with CircuitPython on board. When you plug it in, it will show up as a very small disk drive with main.py on it. Edit main.py with your favorite text editor to build your project using Python, the most popular programming language. No installs, IDE or compiler needed, so you can use it on any computer, even ChromeBooks or computers you can't install software on. When you're done, unplug the Itsy' and your code will go with you.


Manufacturer Adafruit Industries LLC
Category Open Source MCU Platforms
Eval Board Part Number 1528-2554-ND
Eval Board Supplier Adafruit Industries LLC
IDE Arduino IDE, with Software Add-on
Speed 48 MHz
Bits 32 Bit
Memory, Flash/RAM 256 kB + 2 MB / 32 kB
Digital I/O 23 I/O, 18 PWM
Interface I²C x1
SPI x1
USB Device
Analog Outputs (DACs) 1 x 10 Bit
Analog Inputs (ADCs) 11 x 12 Bit
DMA Channels 12
Features 1 x NeoPixel Output
Power/Enable Pin
Real Time Clock
Watch Dog Timers
Radio -
Interrupt Pins 22
I/O Voltage 3.3 V
Voltage In 3.5 ~ 6 V
Touch Sensing Pins 6
Program/Debug Interface USB Type-Micro B
Area 632² mm, 0.98² In
Main I.C. Base Part ATSAMD21
Design Author Adafruit
Date Created By Author 2018-03
Date Added To Library 2019-11

Eval Board

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