CircuitPython 9.2.0-rc.0

This is CircuitPython 9.2.0-rc.0, a release candidate for 9.2.0 final. This release is believed to be stable, and is meant for testing before the final release of 9.2.0.

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

• New audiodelays and audiofilters modules. These modules are experimental, and the API may change.
• Bug fixes.

Notable changes in 9.2.0 from 9.1.x

• Raspberry Pi RP2350 support.
• Update to Espressif ESP-IDF V5.3.1, including new I2C driver.
• Merge MicroPython updates from v1.22.2 and v1.23.
• Espressif BLE improvements.
• Add math.dist().
• _eve updates.
• New busio.I2C.probe() and bitbangio.I2C.probe() methods to check for a single device address.
• ESP32-S3: implement sdioio.
• New audiodelays and audiofilters modules. These modules are experimental, and the API may change.
• Incompatible change: Change default hostname for all Espressif boards to the ESP-IDF default, which is espressif.
• Incompatible change: Use default hostname for mDNS. Fix mDNS collision mangling.

Incompatibility warnings

• Change default hostname for all Espressif boards to the ESP-IDF default, which is espressif. Previous board-specific names were not applied consistently. Use wifi.radio.hostname to set a custom hostname.
• Use default hostname for mDNS. Fix mDNS collision mangling. DNS hostnames will be different.

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 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-beta.1

Fixes and enhancements

• Fix default values for wifi.Radio.start_dhcp_client(). #9751. Thanks @dhalbert.
• Add audiofilters module. #9744. Thanks @dcooperdalrymple.
• Improve _bleio.Connection.bind() validation, error messages, and documentation. #9732. Thanks @dhalbert.
• Add errno.EROFS and errno.ENOSPC. #9731. Thanks @dhalbert.
• adafruit_pixelbuf: allow modifying transmit buffer to control brightness on TM1814 RGB strips. #9730. Thanks @jepler.
• Fix keypad.ShiftRegisterKeys.key_count value. #9719. Thanks @dhalbert.
• Add audiodelays module. #9640. Thanks @gamblor21.

Port and board-specific changes

Broadcom

Espressif

• Disable hardware stack guard while crashes it causes are investigated. #9748. Thanks @dhalbert and MicroPython folks.
• Disable ipv6 RDNSS: LWIP overwrites ipv4 DNS servers. #9713. Thanks @jepler.

i.MX

nordic

renode

RP2

• Explicitly invalidate cache lines on RP2350. #9752. Thanks @tannewt and @earlephilhower.
• Document picodvi differences between RP2040 and RP2350. #9740. Thanks @tannewt.
• Fix assignment to wifi.radio.dns. #9727. Thanks @jepler.

SAMx

SiLabs

Spresense

STM

Individual boards

Documentation changes

• Correct documentation of wifi.Network.authmode. #9725. Thanks @bablokb.
• Improve keypad.ShiftRegisterKeys documentation. #9717. Thanks @aseanwatson.

Build and infrastructure changes

• Update to use macos-12 and ubuntu-24.04 for CI runs. #9720. Thanks @dhalbert.
• Support frozen modules that use a src/ directory. #9673. Thanks @bablokb.

Translation additions and improvements

• Thanks for translations:
  • @andibing (English - UK)
  • @Atalanttore (German)
  • @hexthat (Chinese - Pinyin)
  • @Sokromatrix (German)
  • @wtuemura (Portugese - Brazil)

New boards since 9.2.0-beta.1

• cezerio dev ESP32C6. #9724. Thanks @cezer-io.
• Solder Party ESP32-Pr Stamp XL. #9715. Thanks @solderparty (@arturo182).

Known issues

• See https://github.com/adafruit/circuitpython/issues for other issues, including issues still to be addressed for:
  • 9.2.0
  • 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.