ItsyBitsy NRF52840 Express

by Adafruit

Image of Board

What’s smaller than a Feather but larger than a Trinket? It’s an Adafruit ItsyBitsy nRF52840 Express featuring the Nordic nRF52840 Bluetooth LE processor! Teensy & powerful, with an fast nRF52840 Cortex M4 processor running at 64 MHz and 1 MB of FLASH - this microcontroller board is perfect when you want something very compact, with a heap-load of memory and Bluetooth LE support This Itsy is your best option for tiny wireless connectivity - it can act as both a BLE central and peripheral, with support in both Arduino and CircuitPython

ItsyBitsy nRF52840 Express is only 1.4” long by 0.7” wide, but has 6 power pins, 21 digital GPIO pins (6 of which can be analog in). It’s the same chip as the Feather nRF52840 but really really small. So it’s great for thse really compact builds. It even comes with 2MB of QSPI Flash built in, for data logging, file storage, or CircuitPython code.

The most exciting part of the ItsyBitsy is that while we ship it with an Arduino IDE compatible demo, you can also install CircuitPython on board with only a few clicks. When you plug it in, it will show up as a very small disk drive with on it. Edit with your favorite text editor to build your wireless-enabled 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.




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CircuitPython 5.3.1

This is the latest stable release of CircuitPython that will work with the ItsyBitsy NRF52840 Express.

Start here if you are new to CircuitPython.

Release Notes for 5.3.1

CircuitPython 6.0.0-beta.0

This is the latest unstable release of CircuitPython that will work with the ItsyBitsy NRF52840 Express.

Unstable builds have the latest features but are more likely to have critical bugs.

Release Notes for 6.0.0-beta.0

Built-in modules available: _bleio, _pixelbuf, aesio, analogio, audiobusio, audiocore, audiomixer, audiomp3, audiopwmio, bitbangio, board, busio, digitalio, displayio, framebufferio, gamepad, math, microcontroller, neopixel_write, nvm, os, pulseio, pwmio, random, rgbmatrix, rotaryio, rtc, sdcardio, sharpdisplay, storage, struct, supervisor, terminalio, time, touchio, ulab, usb_hid, usb_midi, vectorio, watchdog

Absolute Newest

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. Try them if you want the absolute latest and are feeling daring or want to see if a problem has been fixed.

Past Releases

All previous releases are listed on GitHub, with release notes, and are available for download from Amazon S3. They are handy for testing, but otherwise we recommend using the latest stable release. Some older GitHub release pages include the same binaries for downloading. But we have discontinued including binaries as assets on newer release pages because of the large number of files for each release.


UF2 Bootloader

Latest version: 0.3.2

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.).

Updating the bootloader on nRF52840 boards is an involved process right now. Follow the instructions in this README. It is not necessary to update on each release if your bootloader is working fine. Read the release notes on GitHub to see what has been changed.

After you update, check INFO_UF2.TXT to verify that the bootloader version has been updated. Then you will need to reload CircuitPython.