ItsyBitsy M4 Express
What’s smaller than a Feather but larger than a Trinket? It’s an Adafruit ItsyBitsy M4 Express featuring the Microchip ATSAMD51! Small, powerful, with a ultra fast ATSAMD51 Cortex M4 processor running at 120 MHz - this microcontroller board is perfect when you want something very compact, with a ton of horsepower and a bunch of pins. This Itsy is like a bullet train, with it’s 120MHz Cortex M4 with floating point support and 512KB Flash and 192KB RAM. Your code will zig and zag and zoom, and with a bunch of extra peripherals for support, this will for sure be your favorite new chipset.
ItsyBitsy M4 Express is only is only 1.4” long by 0.7” wide, but has 6 power pins, 23 digital GPIO pins (7 of which can be analog in, 2 x 1 MSPS analog out DACs, and 18 x PWM out). It’s the same chip as the Adafruit Metro M4 but really really small. So it’s great once you’ve finished up a prototype on a Metro M4 or (the upcoming) Feather M4, 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 M4 is that it ships with CircuitPython on board. When you plug it in, it will show up as a very small disk drive with code.py on it. Edit code.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.
Here are some of the updates you can look forward to when using ItsyBitsy M4:
- Same size, form-factor as the ItsyBitsy 32u4 and ItsyBitsy M0, and nearly-identical pinout as both
- ATSAMD51 32-bit Cortex M4 core running at 120 MHz
- Floating point support with Cortex M4 DSP instructions
- 512 KB flash, 192 KB RAM
- 2 MB SPI FLASH chip for storing files and CircuitPython code storage.
- 32-bit, 3.3V logic and power
- Tons of GPIO! 23 x GPIO pins with following capabilities:
- Dual 1 MSPS 12 bit true analog DAC (A0 and A1) - can be used to play 12-bit stereo audio clips
- Dual 1 MSPS 12 bit ADC (7 analog pins some on ADC1 and some on ADC2)
- 6 x hardware SERCOM - Native hardware SPI, I2C and Serial all available
- 18 x PWM outputs - for servos, LEDs, etc
- No I2S. I2S is only supported on the 64 pin version of this chip. But there’s a stereo DAC you could use.
- 1 x Special Vhigh output pin gives you the higher voltage from VBAT or VUSB, for driving NeoPixels, servos, and other 5V-logic devices. Digital 5 level-shifted output for high-voltage logic level output.
- Can drive NeoPixels or DotStars on any pins, with enough memory to drive 60,000+ pixels. DMA-NeoPixel support on the VHigh pin so you can drive pixels without having to spend any processor time on it.
- Native USB supported by every OS - can be used in Arduino or CircuitPython as USB serial console, Keyboard/Mouse HID, even a little disk drive for storing Python scripts.
- Can be used with Arduino IDE or CircuitPython
- Built in red pin #13 LED
- Built in RGB DotStar LED
- Reset button and pin
- Power with either USB or external output (such as a battery) - it’ll automatically switch over
- Comes pre-loaded with the UF2 bootloader, which looks like a USB storage key. Simply drag firmware on to program, no special tools or drivers needed! It can be used to load up CircuitPython or Arduino IDE (it is bossa v1.8 compatible)
Comes assembled and tested, with headers that can be soldered in for use with a breadboard. ItsyBitsy M4 comes with CircuitPython programmed in.
Have some info to add for this board? Edit the source for this page here.
This is the latest stable release of CircuitPython that will work with the ItsyBitsy M4 Express.
Use this release if you are new to CircuitPython.
Built-in modules available: _asyncio, _bleio, _pixelmap, adafruit_bus_device, adafruit_pixelbuf, aesio, alarm, analogio, array, atexit, audiocore, audioio, audiomixer, audiomp3, binascii, bitbangio, bitmaptools, board, builtins, builtins.pow3, busio, busio.SPI, busio.UART, collections, countio, digitalio, displayio, errno, floppyio, fontio, framebufferio, frequencyio, getpass, gifio, i2ctarget, io, json, keypad, keypad.KeyMatrix, keypad.Keys, keypad.ShiftRegisterKeys, math, microcontroller, msgpack, neopixel_write, nvm, onewireio, os, os.getenv, paralleldisplay, ps2io, pulseio, pwmio, rainbowio, random, re, rgbmatrix, rotaryio, rtc, samd, sdcardio, select, sharpdisplay, storage, struct, supervisor, synthio, sys, terminalio, time, touchio, traceback, ulab, usb_cdc, usb_hid, usb_midi, vectorio, watchdog, zlib
Every time we commit new code to CircuitPython we automatically build binaries for each board and language. The binaries are stored on Amazon S3, organized by board, and then by language. These releases are even newer than the development release listed above. Try them if you want the absolute latest and are feeling daring or want to see if a problem has been fixed.
Previous Versions of CircuitPython
All previous releases of CircuitPython are available for download from Amazon S3 through the button below. For very old releases, look in the OLD/ folder for each board. Release notes for each release are available at GitHub button below.
Older releases are useful for testing if you something appears to be broken in a newer release but used to work, or if you have older code that depends on features only available in an older release. Otherwise we recommend using the latest stable release.
Update UF2 Bootloader
Latest version: v3.15.0
The bootloader allows you to load CircuitPython, MakeCode, and Arduino programs. The bootloader is not CircuitPython. You can check the current version of your bootloader by looking in the INFO_UF2.TXT file when the BOOT drive is visible (FEATHERBOOT, CPLAYBOOT, etc.).
It is not necessary to update your bootloader if it is working fine. Read the release notes on GitHub to see what has been changed. In general, we recommend you not update the bootloader unless you know there is a problem with it or a support person has asked you to try updating it.
To update, first save the contents of CIRCUITPY, just in case. Then double-click the reset button to show the BOOT drive. Drag the update-bootloader .uf2 file to the BOOT drive. Wait a few tens of seconds for the bootloader to update; the BOOT drive will reappear. After you update, check INFO_UF2.TXT to verify that the bootloader version has been updated. Then you will need to reload CircuitPython.