CircuitPython 9.2.1

This is CircuitPython 9.2.1, the latest bugfix revision of CircuitPython, and is a new stable release.

WARNING for nRF52 boards only: If your board has an nRF52 UF2 bootloader whose version is before 0.6.1, you will not be able to load CircuitPython 8.2.0 and later, due to increased size of the firmware. See these instructions for updating your bootloader.

Highlights of this release

• Additional synthio and audiofilters functionality.
• I2CTarget and keys.*.reset() fixes.
• RP2350: PSRAM and cpu.temperature fixes.
• rp2pio: add background read operation.
• Five new boards.

Incompatibility warnings

• Raise TypeError when attempt to produce JSON for invalid types. Previously the types were serialized as strings.

Download from circuitpython.org

Firmware downloads are available from the downloads page on circuitpython.org. The site makes it easy to select the correct file and language for your board.

Installation

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

Try code.circuitpython.org or 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).

Documentation

Documentation is available in readthedocs.io.

Port status

CircuitPython has a number of "ports" that are the core implementations for different microcontroller families. Stability varies on a per-port basis. As of this release, these ports are consider stable (but see Known Issues below):

• atmel-samd: Microchip SAMD21, SAMx5x
• cxd56: Sony Spresense
• espressif: Espressif ESP32, ESP32-S2, ESP32-S3, ESP32-C2, ESP32-C3, ESP32-C6
• nordic: Nordic nRF52840, nRF52833
• raspberrypi: Raspberry Pi RP2040, RP2350
• stm: ST STM32F4 chip family

These ports are considered alpha and will have bugs and missing functionality:

• broadcom: Raspberry Pi boards such as RPi 4, RPi Zero 2W
• espressif: ESP32-P4 (currently no USB support)
• litex: fomu
• mimxrt10xx: NXP i.MX RT10xxx
• renode: hardware simulator
• silabs: Silicon Labs MG24 family
• stm: ST non-STM32F4 chip families

Changes since 9.2.0

Fixes and enhancements

• Fix regression of keypad.*.reset() behavior. #9819. Thanks @aseanwatson and @dhalbert.
• Add finaliser to I2CTarget to fix problems on soft retart. #9810. Thanks @dhalbert.
• Raise TypeError when attempt to produce JSON for invalid types. #9789. Thanks @jepler.
• Add synthio.BlockInput support to synthio.Note waveform loop parameters. #9788. Thanks @relic-se.
• Supply silence when sample missing in audiofilters.Filter. #9787. Thanks @relic-se.
• Force reboot to normal mode after storage.erase_filesystem(). #9786. Thanks @bill88t.
• Add support for tuple of Biquad objects within audiofilters.Filter. #9772. Thanks @relic-se.
• synthio: Add a form of biquad filter, BlockBiquad, that uses BlockInput. #9756. Thanks @jepler.

Port and board-specific changes

Broadcom

Espressif

i.MX

nordic

renode

RP2

• Fix serial REPL bootloop. #9799. Thanks @eightycc.
• Avoid mbedtls function that exists only on RP2040. #9792. Thanks @jepler.
• Fix cpu.temperature on RP2350. #9784. Thanks @bablokb.
• Flush cache properly when PSRAM is in use on RP2350. #9783. Thanks @dhalbert.
• Update cyw43-driver module to match pico-sdk 2.0.0. #9775. Thanks @eightycc.
• Add rp2pio background read operation. #9659. Thanks @timchinowsky.

SAMx

SiLabs

Spresense

STM

Individual boards

• LILYGO T-Deck (Plus): improve port, add support for variant "Plus" functionality. #9815. Thanks @bill88t.
• LILYGO TEMBED ESP32S3: fix display initialization sequence. #9650. Thanks @bytiful.
• Meowbit: enabled gifio, and disable other modules unlikely to be used to make room. #9761. Thanks @dglaude.
• Pimoroni Pico Plus 2: rework pin names. #9803. Thanks @bablokb.
• WIZnet W5100S EVB Pico: Add ssl. #9791. Thanks @anecdata.

Documentation changes

• Fix typo in BusDisplay parameters. #9806. Thanks @RetiredWizard.

Build and infrastructure changes

• Make default unix variant be coverage. #9796. Thanks @jepler.
• Add audiodelays and audioeffects to unix coverage port. #9793. Thanks @jepler.
• Fix security issues in GitHub Actions found by zizmor. #9785. Thanks @jepler.
• Check for proper gcc version when building. #9779. Thanks @jepler.
• Enable vectorio in coverage build. #9766. Thanks @jepler.

Translation additions and improvements

• Thanks for translations:
  • @andibing (English - UK)
  • @hexthat (Chinese - Hanyu Pinyin)
  • @py7hon (Indonesian)
  • @wtuemura (Portugese - Brazil)

New boards since 9.2.0

• 0xCB Gemini. #9801. Thanks @0xCB-dev.
• Bradán Lane STUDIO Coin M0. #9797. Thanks @bradanlane.
• Raspberry Pi Pico 2 W. #9817. Thanks @jepler.
• SparkFun Thing Plus RP2350. #9812. Thanks @sparkfun.
• WIZnet W5100S EVB Pico2. #9791. Thanks @anecdata.

Known issues

• See https://github.com/adafruit/circuitpython/issues for other issues, including issues still to be addressed for:
  • 9.2.x
  • 9.x.x
  • 10.0.0
  • long term
• Native-code .mpy files are not working. This capability is currently enabled only on the winterbloom_sol board.

Thanks

Thank you to all who used, tested, and contributed toward this release, including the contributors above, and many others on GitHub and Discord. Join us on the Discord chat to collaborate.