CircuitPython 9.1.0-beta.1

This is CircuitPython 9.1.0-beta.1, a beta for CircuitPython 9.1.0, and is a new unstable release. This release has known bugs that will be addressed before 9.1.0 final.

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.

Notable changes since 9.0.0

Incompatibility warnings

• API changes to floppyio.
• String values in settings.toml must be quoted.

Audio

• RP2040 I2SOut supports BLCK and LRCLK in either order.

Built-in modules

• Enhance collections.deque functionality.
• Add keypad_demux.DemuxKeyMatrix: use multiplexer for one side of a keypad matrix.
• Add integration-based debouncing to keypad.
• supervisor.Runtime.serial_bytes_available now returns a count instead of a bool.
• Incompatible change: floppyio improvements, including API changes.

Graphics

• fourwire.FourWire: chip_select pin is now optional.
• picodvi now supports 640x240 and 800x240 resolutions.

Internal

• Espressif: update to ESP-IDF v5.2.1.
• Espressif: Change task-switching quantum to 1 millisecond from 10 milliseconds.

Supervisor

• String values in settings.toml must be quoted.

USB

• max3421e USB host support.
• Allow user-specified names for usb_midi interfaces and jacks.

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-C3
• nordic: Nordic nRF52840, nRF52833
• raspberrypi: Raspberry Pi RP2040
• 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
• litex: fomu
• mimxrt10xx: NXP i.MX RT10xxx
• silabs: Silicon Labs MG24 family
• stm: ST non-STM32F4 chip families

Changes since 9.1.0-beta.0

Fixes and enhancements

• Update frozen libraries. #9188. Thanks @dhalbert.
• External flash cache allocation crashed into safe mode when heap was too small. #9187, #9169. Thanks @dhalbert.
• Avoid putting terminal escape sequences in boot_out.txt. #9181. Thanks @bill88t.
• MAX3421E USB host support. #9164. Thanks @tannewt.
• Enable bitmapfilter on boards where it will fit. #9156. Thanks @dhalbert.
• Allow user-specified names for usb_midi interfaces and jacks. #9146. Thanks @brushmate.
• supervisor.Runtime.serial_bytes_available now returns a count instead of a bool. #9141. Thanks @dhalbert
• Correct EPaperDisplay.time_to_refresh. #9140. Thanks @elpekenin.
• floppyio improvements, including API changes. #9135. Thanks @jepler.
• Require strings to be quoted in settings.toml #9117. Thanks @jepler.
• fourwire.FourWire: chip_select pin is now optional. #9106. Thanks @wee-noise-makers.

Port and board-specific changes

Broadcom

Espressif

• Document Espressif AnalogIn limitations. #9137. Thanks @dhalbert.
• Change task-switching quantum to 1 millisecond from 10 milliseconds. #9134. Thanks @dhalbert.
• Handle new ESP-IDF v5.2.1 failure codes for WiFi connections. #9126. Thanks @dhalbert.

i.MX

nordic

• Fix AnalogIn. #9187, #9161, #9114. Thanks @dhalbert.
• Move state word that survives reset to avoid its being overwritten by bootloader. #9160. Thanks @tannewt.

RP2040

• Disable picodvi and usb_host on boards that cannot use them. #9116. Thanks @bablokb.
• picodvi now supports 640x240 and 800x240 resolutions. #9102. Thanks @jepler.

SAMx

• Fix AudioOut timer allocation. #9165. Thanks @dhalbert.

SiLabs

Spresense

STM

Individual boards

• FireBeetle 2 ESP32-S3: fix reset. #9170. Thanks @bill88t.
• ESP32-S3 HackTablet: initialize display. #9157. Thanks @RetiredWizard.
• M5Stack Cardputer: allow input from Cardputer keyboard. #9145. Thanks @joshua-beck-0908.
• Pimoroni InkyFrame 5.7": several updates. #7997. Thanks @bablokb.
• senseBox MCU-S2 ESP32S2: busio.I2C: allow GPIO45, do not check for pullups. #9132. Thanks @mariopesch.

Documentation changes

Build and infrastructure changes

• Fix local and ReadTheDocs documentation builds. #9187, #9185. Thanks @dhalbert.

Translation additions and improvements

• Thanks for translations:
  • @wtuemura (Portuguese - Brazil)

New boards since 9.1.0-beta.0

• MakerGo ESP32C3 Supermini. #9131. Thanks @SeanTheITGuy.
• SQFMI Watchy. #9153. Thanks @joshua-beck-0908.
• Sunton ESP32-2424S012. #9110. Thanks @SeanTheITGuy.
• Sunton ESP32-8048S070. #9149. Thanks @SeanTheITGuy.
• Waveshare RP2040-GEEK. #9187, #9090. Thanks @RetiredWizard.

Known issues

• See https://github.com/adafruit/circuitpython/issues for other issues, including issues still to be addressed for:
  • 9.0.x
  • 9.1.0
  • 9.x.x
  • long term

Thanks

Thank you to all who used, tested, and contributed since 9.1.0-beta.0, including the contributors above, and many others on GitHub and Discord. Join us on the Discord chat to collaborate.