This is the latest stable release of CircuitPython that will work with the SAMD21 Dev.
Start here if you are new to CircuitPython.
Built-in modules available: analogio, board, busio, digitalio, math, microcontroller, neopixel_write, nvm, os, pwmio, rainbowio, random, rotaryio, rtc, storage, struct, supervisor, time, touchio, usb_cdc, usb_hid, usb_midi
This is the latest unstable release of CircuitPython that will work with the SAMD21 Dev.
Unstable builds have the latest features but are more likely to have critical bugs.
Built-in modules available: analogio, array, board, builtins, busio, collections, digitalio, math, microcontroller, neopixel_write, nvm, os, pwmio, rainbowio, random, rotaryio, rtc, storage, struct, supervisor, sys, time, touchio, usb_cdc, usb_hid, usb_midi
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.
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.
Update UF2 Bootloader
Latest version: v3.14.0
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.