From the GitHub release page:

This is the first alpha release of CircuitPython 6.0.0. It is a renumbered version of 5.4.0 because i2cslave module and class have been renamed to i2cperipheral. It is alpha because we may remove or rename additional APIs. It is relatively stable.

Feature-wise, this stable release adds basic lower power support when in time.sleep() and initial ESP32-S2 support. The lower power work changed time keeping and may have introduced bugs. Please use 5.3.0 if you need a stable version of CircuitPython.

Download from circuitpython.org

Downloads are available from circuitpython.org! The site makes it easy to select the correct file and language for your board. The downloads page is here. Downloads are no longer available from the GitHub release pages because of the large number of files for each release.

Installation

To install follow the instructions in our new Welcome to CircuitPython! guide. To install the latest libraries, see this page in that guide.

Try the latest version of the Mu editor for creating and editing your CircuitPython programs and for easy access to the CircuitPython serial connection (the REPL).

New features and improvements since 5.4.0 Beta 1

• Added sdioio and sdcardio for native SDCard support. Available on SAMD51 and spresense. Thanks to @jepler and @kamtom480.
• Added busio support to ESP32-S2. Thanks to @tannewt
• Add support for SAME54. Thanks to @jepler
• Add global navigation satellite system (gnss) support for Spresense. Thanks to @kamtom480
• Improved ESP32-S2 performance. Thanks to @tannewt and @DavePutz
• Updated ulab thanks to @jepler and @v923z
• Fix time.sleep() after it has been ctrl-c’d. Thanks to @DavePutz
• Fix microcontroller.cpu.temperature read hang. Thanks to @dhalbert
• Fix ScanEntry prefix matching when any=False. Thanks to @dhalbert
• Fixed port D pins on STM32 LQFP64 boards. Thanks to @hierophect
• Fixed I2C timing on STM32 F7 and H7. Thanks to @hierophect
• Fixed display refresh when changing palette transparency. Thanks to @DavePutz
• Meowbit build is now UF2 rather than a bin. Thanks to @hierophect
• Documentation improvements thanks to @AndrewR-L
• Improved Dutch, German, Brazilian Portuguese and Spanish translations. Thanks to @buchen, @fede2cr, @ryevertigo, and @wtuemura.

Full commit log is here.

Breaking changes since 5.x

• i2cslave is now i2cperipheral and the class in it is changed as well.

New boards since 5.4.0 Beta 1

• Seeeduino Wio Terminal Thanks to @ansonhe97
• Atmel SAME54 Xplained Thanks to @jepler
• Loc Ber M4 Thanks for @florin-trutiu
• UnexpectedMaker FeatherS2 Thanks to @tannewt and @unexpectedmaker

Known Issues

• displayio operations that read from an SD card (e.g., OnDiskBitmap) will interfere with other SD card operations and can cause lockup. To work around this problem, do not read or write files on the SD while the display is updating, and vice versa.
• pulseio.PulseIn isn’t reliable on SAMD21. #3049
• Performance has dropped since 5.3.0 due to excessive background work. #2929
• See https://github.com/adafruit/circuitpython/issues for other issues.

Thanks

Thank you to all who used, tested, contributed since 5.4.0 Beta 1, helped out, and participated on GitHub and/or Discord, including @ansonhe97, @buchen, @DavePutz, @deshipu, @dhalbert, @fede2cr, @florin-trutiu, @hierophect, @jepler, @jerryneedell, @kamtom480, @kattni, @k0d, @ladyada, @PTS93, @rhooper, @sommersoft, @v923z, @wtuemura and surely more we have missed. Join us on the Discord chat to collaborate.

Documentation

Documentation is available in readthedocs.io.

This release is based on MicroPython 1.9.4 @25ae98f. Support upstream MicroPython by purchasing a PyBoard (from Adafruit here) or sponsoring MicroPython on GitHub.

Translations

One important feature of CircuitPython is translated control and error messages. With the help of fellow open source project Weblate, we’re making it even easier to add or improve translations. Sign in with an existing account such as Github, Google or Facebook and start contributing through a simple web interface. No forks or pull requests needed!

Troubleshooting

Check out this guide for info on common problems with CircuitPython. If you are still having issues, then post to the Adafruit Support Forums and join Discord.

Assets

Builds are no longer stored as assets on this release page, because there are too many of them. Please see the Download from circuitpython.org section above.