From the GitHub release page:
3.0.0 is the latest major revision of CircuitPython and features new support for the SAMD51 (aka M4) and preliminary support for the nRF52 BLE chipset. It also features better memory utilization so more can be loaded in the same amount of space.
This is an alpha release of 3.0.0. Alpha releases do not have the complete API from 2.x and are only meant for testing. (Beta release will have the full API but still need work.) Please use the latest stable release when first starting with CircuitPython. It is stable.
Changes since Alpha 2
- Fix DotStar support so user code can access it. Thanks @siddacious!
- Update the driver guide page! Thanks @sommersoft, @tannewt and @kattni.
- Use DMA for SPI transactions including those to SPI Flash. Thanks @tannewt and @dhalbert.
gamepadin 3.0.0. Thanks @deshipu and @dhalbert.
- Correct timer definitions on SAMD21 so that pins are picked correctly. Thanks to @kattni, @hukuzatuna, @tannewt and @dhalbert.
- Squash a USB concurrency bug which led to incorrectly loaded data and connection instability. Thanks @jerryneedell and @siddacious for finding the issue and @tannewt and @dhalbert for fixing it.
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).
All builds except ESP8266 are available as both UF2 and bin files here along with test builds.
New Features in 3.0.0
- Support for SAMD51 based M4 boards from Adafruit. Thanks @tannewt, @dhalbert, @siddacious and all the M4 testers.
- Preliminary support for nRF52 BLE capable boards. Thanks @glennrub, @tralamazza, @microbuilder, @arturo182, @hathach and @jerryneedell.
- Long-lived heap allocations are better compacted. (Video) Thanks @tannewt and @dhalbert.
- Read the microcontroller’s unique id through
microcontroller.cpu.uid. Thanks @sommersoft!
- UART can now be created with only one direction. Thanks @dhalbert!
- Code has been reorganized to ease sharing main code across ports.
ustructhas been replaced with
structto match CPython.
- The mpy format has changed so make sure and use a 3.0.0 bundle for libraries.
Thank you to all who used, tested, contributed, helped out, and participated on GitHub and/or Discord:
@ladyada, @dhalbert, @tannewt, @microbuilder, @arturo182, @jamesadevine, @tralamazza, @hathach, @glennrub, @siddacious, @deshipu, @tdicola, @mrmcwethy, @willingc, @sommersoft, @deanm1278, @jerryneedell, @stewmystre, @boneskull, @Sigafoos, @brentru, @caternuson, @process1183, @Andon-A, @asherlie, adamwolf, dastels, @hukuzatuna, @KurticusMaximus, nis, BravoDelta, aj_nys, @wolf, @vesperk38 and surely more we have missed. Join us on the Discord chat to collaborate.
Documentation is available in readthedocs.io.
Here are all the changes since 2.2.3.