This is CircuitPython 10.4.0-alpha.2, an alpha release for 10.4.0. Further features, changes, and bug fixes will be added before the final release of 10.4.0.

Highlights of changes since 10.3.1

• 5 GHz WiFi support.
• Allow importing turbo (@viper and @native) .mpy files on many espressif, nordic, and SAMx5x boards (already enabled on RP2xxx).
• BLE numeric-comparison (PIN) pairing on Espressif.
• Merge from MicroPython v1.28 and v1.29.
• Many bug fixes.

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-C2, ESP32-C3, ESP32-C5, ESP32-C6, ESP32-C61, ESP32-H2, ESP32-S2, ESP32-S3
• 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:

• analog: Analog Devices MAX32690
• broadcom (will be removed in CircuitPython 11): Raspberry Pi boards such as RPi 4, RPi Zero 2W
• espressif: ESP32-P4
• litex: fomu
• mimxrt10xx: NXP i.MX RT10xxx
• renode: hardware simulator
• silabs: Silicon Labs MG24 family
• stm: ST non-STM32F4 chip families
• zephyr: multiplatform RTOS, running on multiple chip families

Changes since 10.3.1

Fixes and enhancements

• Fix argument validations, internal calculations, and edge cases in many places, including audio code. #11385, #11384, #11381, #11378, #11377, #11370, #11368, #11367. Thanks @peterbay.
• Allow 5 GHz channels in wifi.Monitor. #11375. Thanks @mikeysklar.
• Allow 5 GHz channels in wifi.Radio.start_ap(). #11374. Thanks @mikeysklar.
• Compress localized messages further. #11373, #11369. Thanks @dhalbert.
• Save firmware space by shrinking property objects on more ports. #11371. Thanks @lynt-smitka.
• Allocate space only for terminal font glyphs that exist. #11365. Thanks @lynt-smitka.
• Set ARM Thumb bit on code pointers consistently. #11361. Thanks @mikeysklar.
• Merge from MicroPython v1.29.0. #11349. Thanks @mikeysklar.
• Merge from MicroPython v1.28.0. #11334. Thanks @mikeysklar.
• wifi.Radio.connect() can now take a Network from scan result. #11309. Thanks @mikeysklar.

Port and board-specific changes

Analog Devices

Broadcom

Espressif

• Enable turbo (@viper and @native) .mpy loading. #11392. Thanks @mikeysklar.
• BLE numeric-comparison pairing. #11340. Thanks @mmabey.

i.MX

Nordic

• Enable turbo (@viper and @native) .mpy loading. #11360. Thanks @mikeysklar.

renode

RP2xxx

• Use a smaller version of the internal timezone code. #11379. Thanks @lynt-smitka.

SAMx

• Enable turbo (@viper and @native) .mpy loading. #11356. Thanks @mikeysklar.

SiLabs

Spresense

STM

• Enable turbo (@viper and @native) .mpy loading. #11355. Thanks @mikeysklar.

Zephyr

• Correct staleness check for autogen_board_info.toml. #11396. Thanks @mikeysklar.
• Fix BLE problems, including those affecting BLE workflow. #11366. Thanks @dhalbert.
• In tests, read serial output in chunks instead of one byte at a time. #11353. Thanks @lynt-smitka.
• Run tests in parallel. #11348. Thanks @lynt-smitka.
• In CI runs, cache each port's submodules in its own cache entry. #11345. Thanks @lynt-smitka.
• Limit west update to projects we actually use. #11344. Thanks @lynt-smitka.
• Only build boards that enabled a changed module. #11316. Thanks @lynt-smitka.

Individual boards

Pimoroni PicoSystem: enable picogame. #11359. Thanks @lynt-smitka.

Documentation changes

Build and infrastructure changes

• Experiment with merge queues. #11399, #11398, #11390, #11389, #11388, #11387. Thanks @tannewt.
• Cancel PR merge runs when a later PR is merged, to save CI time. #11388. Thanks @tannewt.
• Regenerate translation data when TRANSLATION is changed in a build directory. #11372. Thanks @dhalbert.

Translation additions and improvements

New boards

• SecuringHardware.com Xiaomao. #11395. Thanks @securelyfitz.

Known issues

• See https://github.com/adafruit/circuitpython/issues for other issues, including issues still to be addressed for:
  • 10.3.x
  • 10.x.x
  • 11.0.0
  • long term

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.

This is CircuitPython 10.3.1, a bugfix revision of CircuitPython, and is a new stable release.

Highlights of changes since 10.3.0

• Allow importing turbo (@viper and @native) .mpy files on RP2xxx boards. More to come.
• Espressif ESP32-C5 support.
• Espressif and nordic BLE fixes that improve BLE workflow.
• Many other bug fixes.
• Many build infrastructure improvements and speedups.

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-C2, ESP32-C3, ESP32-C5, ESP32-C6, ESP32-C61, ESP32-H2, ESP32-S2, ESP32-S3
• 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:

• analog: Analog Devices MAX32690
• broadcom (will be removed in CircuitPython 11): Raspberry Pi boards such as RPi 4, RPi Zero 2W
• espressif: ESP32-P4
• litex: fomu
• mimxrt10xx: NXP i.MX RT10xxx
• renode: hardware simulator
• silabs: Silicon Labs MG24 family
• stm: ST non-STM32F4 chip families
• zephyr: multiplatform RTOS, running on multiple chip families

Changes since 10.3.0

Fixes and enhancements

• Keep serving web workflow after a watchdog reset. #1337. Thanks @grgrant.
• Add a guard service to BLE workflow services so user-created services won't cause problems. #11333. Thanks @dhalbert.
• Allow loading "turbo" (native and viper) .mpy files without adding the @native and @viper compilers. #11332, #11331. Thanks @mikeysklar.
• Fix WaveFile 8-bit sample padding at end of file. #11320. Thanks @4RH1T3CT0R7.
• Validate epoch_time in TimeAlarm. #11318. Thanks @4RH1T3CT0R7.
• Allow scanning 5 GHz WiFi channels on dual-band boards. #11308. Thanks @mikeysklar.
• Validate passed display in picogame. #11306. Thanks @lynt-smitka.
• Add freeze property to audiodelays.PitchShift. #11293. Thanks @relic-se.
• Fix dirty-rectangle checks in picogame. #11290. Thanks @lynt-smitka.
• Fix dropped note when re-pressed after decay in synthio #11289. Thanks @bdbarnett.
• Fix regression in LED status code display. #11288. Thanks @dhalbert.
• usb_hid: honor boot protocol request that arrives after startup. #11282. Thanks @mikeysklar.
• Fix synthio Biquad filter reset. #11278. Thanks @bdbarnett.
• Fix audiofilters.Distortion(soft_clip=False). #11277. Thanks @bdbarnett.
• Fix synthio oscillator wrapping one sample late. #11276. Thanks @bdbarnett.
• Fix synthio Biquad filter computation. #11275. Thanks @bdbarnett.
• Mark usb_audio.Speaker OUT adaptive so Windows UAC2 driver can start. #11256. Thanks @jbirchall-svg.

Port and board-specific changes

Analog Devices

Broadcom

Espressif

• Fix touchio.TouchIn regression. #11307. Thanks @dhalbert.
• Don't run out of space for BLE CCCDs. #11304. Thanks @dhalbert.
• Don't drop Characteristic.value notifications under load. #11301. Thanks @dhalbert.
• Add ESP32-C5 support. #11297. Thanks @mikeysklar.
• Don't lose _bleio.PacketBuffer data when buffers are temporarily not available. #11286. Thanks @dhalbert.
• Don't clear sleep memory after a reload; only clear after hard reset. #11274. Thanks @mikeysklar.

i.MX

Nordic

• Fix hardcrash when activating watchdog in boot.py. micropython#11925. Thanks @FoamyGuy.
• Add emmcio module, currently only used for Teenage Engineering SP-1. #11257. Thanks @FoamyGuy.

renode

RP2xxx

• Fix mDNS WiFI hostname. #11035. Thanks @grgrant.

SAMx

SiLabs

Spresense

STM

• Make entering bootloader more robust by retrying. #11270. Thanks @mikeysklar.

Zephyr

• nrf7002dk: give slot0 the unused 32 kB storage partition. #11335. Thanks @mikeysklar.
• RP2xxx: make nvm size be a whole erase block. #11272. Thanks @lynt-smitka.
• Build changes:
  • Build translations more selectively. #11336. Thanks @lynt-smitka.
  • Run tests only when a change can reach them. #11327. Thanks @lynt-smitka.
  • Allow display capture tests to stop the simulator after the last display write. #11323. Thanks @lynt-smitka.
  • Add asan native_sim build. #11317. Thanks @tannewt.
  • Install 32-bit SDL2 packages only for native_sim. Thanks @lynt-smitka.
  • Use Python 3.13 for board jobs because wheels do not yet exist for some 3.14 packages. #11312. Thanks @lynt-smitka.
  • Check that zephyr board firmware layouts match the non-zephyr builds for those boards. #11310. THanks @lynt-smitka.
  • Use dummy SDL video driver for native_sim. #11303. Thanks @tannewt.
  • Use autogen for emmcio, picogame, board. #11296. Thanks @tannewt.
  • Run tests in their own workflow. #11294. Thanks @mikeysklar.
  • Increase timeouts for test_saved_word test. #11280. Thanks @dhalbert.
  • Add partition layout check. #11273. Thanks @lynt-smitka.
  • Add ranges to partitions node. #11271. Thanks @lynt-smitka.
  • Ignore more file changes that don't affect board builds. #11264. Thanks @tannewt.

Individual boards

• Pajenicko PicoPad: Use 62.5 MHz for display SPI frequency. #11291. Thanks @lynt-smitka.

Documentation changes

Build and infrastructure changes

• Run zephyr tests as three jobs, to improve parallelism. #11350. Thanks @lynt-smitka.
• Add lib/mp3 as a dependency for mimxrt10xx in ci_fetch_deps.py. #11346. Thanks @lynt-smitka.
• Get ninja from ESP-IDF tools instead of fetching it again with apt. #11343. Thanks @lynt-smitka.
• Fix unix coverage build on arm64. #11330. Thanks @4RH1T3CT0R7.
• Predict translation sizes to avoid needing to build translations that will not overflow during PR runs. #11326. Thanks @lynt-smitka.
• Split ports with more than 256 board jobs into several matrix jobs. #11325. Thanks @lynt-smitka.
• Build firmware.size.json in all cases now. #11314. Thanks @lynt-smitka.
• use -j$(nproc) for make parallelism. #11313. Thanks @lynt-smitka.

Translation additions and improvements

New boards

• Challenger RP2040 NFC. #11321. Thanks @TheFilipcom4607.
• Espressif ESP32-C5-DevKitC-1-N8R8. #11297. Thanks @mikeysklar.
• Teenage Engineering SP-1. #11298, #11261. Thanks @FoamyGuy.

Known issues

• See https://github.com/adafruit/circuitpython/issues for other issues, including issues still to be addressed for:
  • 10.3.x
  • 10.x.x
  • 11.0.0
  • long term

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.

This is CircuitPython 10.3.0, a minor revision of CircuitPython, and is a new stable release.

Notable additions, changes, and fixes in 10.3.0 from 10.2.1

Gaming and Display

• picogame game engine module, a performant game-oriented alternative to displayio.
• E-ink display quality improvements, including on MagTag 2025.

Audio

• audio.AudioOut, using DAC, now available on STM.
• audio_i2sin, available on Espressif and RP2xxx.
• audiofilewriter, to send an audio pipeline stream to a file.
• audiodelays.Flanger, audiodelays.GranularPitchShift.
• audiospeed.Resampler.
• audiodelays, audiofilters, and audiofreeverb now available on RP2xxx.
• synthio.Biquad filters now available in audiodelays.Echo and audiofreeverb.Freeverb.
• usb_audio.USBMicrophone and usb_audio.USBSpeaker, which provide audio source and sink USB devices.
• Duplex I2S.

settings.toml

• CIRCUITPY_BLE_WORKFLOW toggle.
• CIRCUITPY_HEAP_SRAM_SIZE.
• CIRCUITPY_SAFE_MODE_DELAY time value.
• CIRCUITPY_SDCARD_USB toggle.
• CIRCUITPY_WIFI_HOSTNAME.
• Float values can now be specified.

Storage

• sdioio now available on RP2xxx.
• storage.unsafe_disable_usb_drive() can disable the USB CIRCUITPY drive after the host has mounted it.

Fixes

• ESP-NOW works again.
• USB host fixes.
• BLE workflow fixes (more to come).

Highlights of changes since 10.3.0-rc.0

• Fix build failures.
• Update RP2350 PSRAM timing when processor frequency changes.

Incompatibility warnings when upgrading to 10.3.0 from 10.2.1

• The baudrate specified in busio.SPI.configure() is now a ceiling, and will not be exceeded. Previously, on some ports, the actual baudrate chosen could have been the nearest available baudrate, but higher than the specified baudrate, sometimes by a substantial amount. Use SPI.frequency to fetch the actual baudrate. Limitations: On Zephyr, SPI.frequency is the specified, not the actual baudrate, and some Zephyr ports may violate the ceiling behavior.

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-C2, ESP32-C3, ESP32-C6, ESP32-C61, ESP32-H2, ESP32-S2, ESP32-S3
• 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:

• analog: Analog Devices MAX32690
• broadcom (will be removed in CircuitPython 11): Raspberry Pi boards such as RPi 4, RPi Zero 2W
• espressif: ESP32-P4
• litex: fomu
• mimxrt10xx: NXP i.MX RT10xxx
• renode: hardware simulator
• silabs: Silicon Labs MG24 family
• stm: ST non-STM32F4 chip families
• zephyr: multiplatform RTOS, running on multiple chip families

Changes since 10.3.0-rc.0

Fixes and enhancements

Port and board-specific changes

Analog Devices

Broadcom

Espressif

i.MX

Nordic

renode

RP2xxx

• Derive PSRAM QMI timings from system clock rate. #11250. Thanks @ladyada.

SAMx

SiLabs

Spresense

STM

Zephyr

• Raise test timeouts. #11262. Thanks @tannewt.
• Build nRF54lm20 bsim. #11262. Thanks @tannewt.

Individual boards

Adafruit PyBadge: shrink build. #11263. Thanks @dhalbert.

Documentation changes

Build and infrastructure changes

Translation additions and improvements

New boards

Known issues

• See https://github.com/adafruit/circuitpython/issues for other issues, including issues still to be addressed for:
  • 10.3.x
  • 10.x.x
  • 11.0.0
  • long term

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.

This is CircuitPython 10.3.0-rc.0, a release candidate for CircuitPython 10.3.0 final. CircuitPython 10.3.0 will be the latest minor revision of CircuitPython, and will be a new stable release.

Notable additions, changes, and fixes in 10.3.0 from 10.2.1

Gaming and Display

• picogame game engine module, a performant game-oriented alternative to displayio.
• E-ink display quality improvements, including on MagTag 2025.

Audio

• audio.AudioOut, using DAC, now available on STM.
• audio_i2sin, available on Espressif and RP2xxx.
• audiofilewriter, to send an audio pipeline stream to a file.
• audiodelays.Flanger, audiodelays.GranularPitchShift.
• audiospeed.Resampler.
• audiodelays, audiofilters, and audiofreeverb now available on RP2xxx.
• synthio.Biquad filters now available in audiodelays.Echo and audiofreeverb.Freeverb.
• usb_audio.USBMicrophone and usb_audio.USBSpeaker, which provide audio source and sink USB devices.
• Duplex I2S.

settings.toml

• CIRCUITPY_BLE_WORKFLOW toggle.
• CIRCUITPY_HEAP_SRAM_SIZE.
• CIRCUITPY_SAFE_MODE_DELAY time value.
• CIRCUITPY_SDCARD_USB toggle.
• CIRCUITPY_WIFI_HOSTNAME.
• Float values can now be specified.

Storage

• sdioio now available on RP2xxx.
• storage.unsafe_disable_usb_drive() can disable the USB CIRCUITPY drive after the host has mounted it.

Fixes

• ESP-NOW works again.
• USB host fixes.
• BLE workflow fixes (more to come).

Highlights of this release

• Add picogame game engine module.
• Add CIRCUITPY_HEAP_SRAM_SIZE setting in settings.toml.
• Add audiodelays.Flanger.
• Add synthio.Biquad filters to audiodelays.Echo and audiofreeverb.Freeverb.
• Implement duplex I2S.
• Add stereo support to usb_audio.
• BLE workflow fixes (more to come).
• Zephyr BLE support.
• Many other Zephyr, additions, fixes, and new boards.

Incompatibility warnings when upgrading to 10.3.0 from 10.2.1

• The baudrate specified in busio.SPI.configure() is now a ceiling, and will not be exceeded. Previously, on some ports, the actual baudrate chosen could have been the nearest available baudrate, but higher than the specified baudrate, sometimes by a substantial amount. Use SPI.frequency to fetch the actual baudrate. Limitations: On Zephyr, SPI.frequency is the specified, not the actual baudrate, and some Zephyr ports may violate the ceiling behavior.

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-C2, ESP32-C3, ESP32-C6, ESP32-C61, ESP32-H2, ESP32-S2, ESP32-S3
• 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:

• analog: Analog Devices MAX32690
• broadcom (will be removed in CircuitPython 11): Raspberry Pi boards such as RPi 4, RPi Zero 2W
• espressif: ESP32-P4
• litex: fomu
• mimxrt10xx: NXP i.MX RT10xxx
• renode: hardware simulator
• silabs: Silicon Labs MG24 family
• stm: ST non-STM32F4 chip families
• zephyr: multiplatform RTOS, running on multiple chip families

Changes since 10.3.0-alpha.4

Fixes and enhancements

• Keep BLE workflow connection alive across VM restarts when possible. #11255. Thanks @dhalbert.
• Update frozen libraries. #11244. Thanks @dhalbert.
• Fix card size for SDXC cards larger than 32 GB. #11243, #11013. Thanks @mikeysklar.
• On boards that use a button to enter safe mode or BLE discovery, provide LED feedback the user successfully entered those modes. #11232. Thanks @dhalbert.
• Fix some cross-platform BLE bugs. #11225. Thanks @dhalbert.
• Prevent MP3Decoder input corruption. #11219. Thanks @FoamyGuy.
• Report individual error code for gaierror in socketpool. #11215. Thanks @mikeysklar.
• Prevent audiomixer.Mixer from resetting all voices when played. #11211. Thanks @relic-se.
• Check traceback arguments more carefully. #11209. Thanks @dhalbert.
• Check for failures when creating web workflow listening socket. #11207. Thanks @mikeysklar.
• Add picogame game engine module. #11199. Thanks @lynt-smitka.
• Add synthio.Biquad filters to audiodelays.Echo and audiofreeverb.Freeverb. #11196. Thanks @relic-se.
• Improve usb_audio.Microphone. #11195. Thanks @mikeysklar.
• Prevent click noise on audiomixer.Mixer and synthio.Synthesizer during volume updates. #11194. Thanks @relic-se.
• Fix synthio.Note.panning. #11191. Thanks @relic-se.
• Merge overlapping dirty rectangles in busdisplay. #11189. Thanks @lynt-smitka.
• Return text errors for SSL certificat verification failures. #11183. Thanks @dhalbert.
• Fix mdns crashes. #11181. Thanks @dhalbert.
• Remove previously added I2SIn invert_bit_clock argument. #11177. Thanks @FoamyGuy.
• Add CIRCUITPY_HEAP_SRAM_SIZE setting in settings.toml. #11176. Thanks @lynt-smitka.
• Add audiodelays.Flanger. #11175. Thanks @FoamyGuy.
• Fix crashes caused by deinited audiosample objects. #11154. Thanks @FoamyGuy.
• For _bleio HCI, fill in error information for ATT Error Response. #11145. Thanks @annejan.
• Validate that an expected audiosample argument is really one, in many places. #11138. Thanks @dhalbert.
• Add raise_on_timeout=False option to usb_core.Device.read. #11137. Thanks @lynt-smitka.
• Implement duplex I2S. #11136. Thanks @FoamyGuy.
• Add stereo support to usb_audio. #11102. Thanks @relic-se.

Port and board-specific changes

Analog Devices

Broadcom

Espressif

• Read MAC address from eFuse so WiFi does not need to be enabled to fetch the address. #11238. Thanks @mikeysklar.
• Accept a BLE re-pairing request from a peer already bonded to the board. #11237. Thanks @dhalbert.
• Require encryption to write CCCD of an encrypted characteristic. #11236. Thanks @dhalbert.
• Fix busio.UART CTS flow control. #11162. Thanks @tannewt.

i.MX

Nordic

• Fix AnalogIn issue: value sometimes 0. #11253. Thanks @FoamyGuy.
• Support external_clock on I2SOut. #11252. Thanks @FoamyGuy.
• Allow SoftDevice to be optional, for boards that don't use BLE. #11251. Thanks @FoamyGuy.
• Fix some platform-specific BLE bugs. #11225. Thanks @dhalbert.
• Support two stop bits in busio.UART. #11169. Thanks @dhalbert.

renode

RP2xxx

• Add GD25Q64 flash chips as an alternative for W25Q64 on several boards. #11249. Thanks @tannewt.
• Turn off CIRCUITPY_I2CIOEXPANDER except on yoto boards. #11241. Thanks @dhalbert.
• Add Framebuffer.wait_for_vblank() to allow tear-free repaints. #11187. Thanks @lynt-smitka.
• Support multicast TTL sockets. #11174. Thanks @Daniiiil1.
• Update mbedtls from 2.28.3 to 4.2.0. #11156. Thanks @dhalbert.
• Add wiznet PIO SPI support. #10440. Thanks @wizhannah.

SAMx

• Handle SAME51 board builds properly. #11143. Thanks @dhalbert.

SiLabs

Spresense

• Raise NotImplementedError for os.urandom() instead of returning a non-TRNG value. #11184. Thanks @dhalbert.

STM

Zephyr

• Support saved words across hard resets. #11254. Thanks @tannewt.
• Use WiFi MAC for cpu.uid when hardware unique ID is not available. #11246. Thanks @mikeysklar.
• Add ulab. #11245. Thanks @mikeysklar.
• Fix BLE name. #11239. Thanks @tannewt.
• Keep board overlays and Kconfig fragments in the board folder. #11235. Thanks @lynt-smitka.
• Fix flash partition specification. #11234. Thanks @lynt-smitka.
• Turn on some MICROPY speed improvement options that were off by default. #11233. Thanks @lynt-smitka.
• Handle heap regions that are too small for use. #11230. Thanks @mikeysklar.
• Add WiFi station connect, IPv4 address fetching, wifi.radio.addresses, proper authmode reporting, MAC address fetching. #11228. Thanks @mikeysklar.
• Route WiFi diagnostics through the log subsystem. #11227. Thanks @mikeysklar.
• Enable BLE workflow. #11226. Thanks @tannewt.
• Fix WiFi network scanning. #11223. Thanks @mikeysklar.
• Handle reading vendor index from vendor directory. #11220. Thanks @mikeysklar.
• Handle missing labels for keys/buttons. #11210. Thanks @mikeysklar.
• Add usb_hid. #11201. Thanks @tannewt.
• Add BLE pairing and bonding. #11200. Thanks @tannewt.
• Enable asyncio, binascii, json, re, and select. #11180. Thanks @tannewt.
• Implement _bleio GATT functionality. #11179. Thanks @tannewt.
• Update to latest version of Zephyr. #11171. Thanks @tannewt.
• Fix left justified I2SIn with external clock. #11170. Thanks @relic-se.

Individual boards

• Adafruit Memento: turn off presenting SD c...

This is CircuitPython 10.3.0-alpha.4, an alpha release for 10.3.0. Further features, changes, and bug fixes will be added before the final release of 10.3.0.

Highlights of this release

• Add audiofilewriter.
• Add audiodelays.GranularPitchShift.
• Add sdioio, audiodelays, audiofilters, and audiofreeverb on RP2xxx.
• Add CIRCUITPY_BLE_WORKFLOW, CIRCUITPY_SAFE_MODE_DELAY, and CIRCUITPY_WIFI_HOSTNAME to settings.toml.
• Add storage.unsafe_disable_usb_drive(), to disable the USB CIRCUITPY drive after the host has mounted it.
• Lower the default WiFi power from 20 dBm to 15 dBm on all boards with chip antennas
• USB host fixes.
• Espressif BLE fixes.
• ESP-NOW works again on Espressif.
• Update TinyUSB.

Incompatibility warnings when upgrading to 10.3.0 from 10.2.x

• The baudrate specified in busio.SPI.configure() is now a ceiling, and will not be exceeded. Previously, on some ports, the actual baudrate chosen could have been the nearest available baudrate, but higher than the specified baudrate, sometimes by a substantial amount. Use SPI.frequency to fetch the actual baudrate. Limitations: On Zephyr, SPI.frequency is the specified, not the actual baudrate, and some Zephyr ports may violate the ceiling behavior.

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-C2, ESP32-C3, ESP32-C6, ESP32-C61, ESP32-H2, ESP32-S2, ESP32-S3
• 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:

• analog: Analog Devices MAX32690
• broadcom: Raspberry Pi boards such as RPi 4, RPi Zero 2W (will be removed in CircuitPython 11)
• espressif: ESP32-P4
• litex: fomu
• mimxrt10xx: NXP i.MX RT10xxx
• renode: hardware simulator
• silabs: Silicon Labs MG24 family
• stm: ST non-STM32F4 chip families
• zephyr: multiplatform RTOS, running on multiple chip families

Changes since 10.3.0-alpha.3

Fixes and enhancements

• Update frozen libraries. #11129. Thanks @dhalbert.
• Add storage.unsafe_disable_usb_drive(), which disables the CIRCUITPY drive even after it was enumerated as a USB drive. The drive is marked as "not ready". This allows writing to the drive from the REPL or from code without a remount() in boot.py.
• Allow non-boot-protocol keyboards to be used with USB host. #11126. Thanks @mikeysklar.
• Do not do BLE bonding delay (blue flashes) when waking from deep sleep. #11123. Thanks @dhalbert.
• Add CIRCUITPY_BLE_WORKFLOW in settings.toml for enabling/disabling BLE workflow. #11123. Thanks @dhalbert.
• Add audiodelays.GranularPitchShift. #11121. Thanks @FoamyGuy.
• Fix handling of .. in beginning of file paths. #11113. Thanks @94xhn.
• Fix native modules (.mpy files with native machine code). #11112. Thanks @jepler.
• Improve PWMOut constructor failure error messages. #11107. Thanks @dhalbert.
• Add audiofilewriter module, an audio sink that writes to a file. #11106. Thanks @FoamyGuy.
• Update TinyUSB, including MAX3421E fix. #11093. Thanks @mikeysklar.
• Fix preserve_dios during fake deep sleep. #11087. Thanks @dhalbert.
• Fix non-looping audio playback. #11085. Thanks @dhalbert.
• busio.SPI: do not exceed specified baudrate. #11081. Thanks @dhalbert.
• Fix BLE crash on AirLift restart. #11077. Thanks @dhalbert.
• Add CIRCUITPY_SAFE_MODE_DELAY in settings.toml: sets time allowed for user-initiated safe mode during startup. #11073. Thanks @dhalbert.
• Add CIRCUITPY_WIFI_HOSTNAME in settings.toml: sets hostname prior to WiFi connect. #11072. Thanks @dhalbert.
• Improvements to I2SIn streaming protocol. #11068. Thanks @FoamyGuy.

Port and board-specific changes

Analog Devices

Broadcom

Espressif

• Lower default WiFi power to from 20 dBm to 15 dBm on all boards with chip antennas. #11132. Thanks @dhalbert.
• Deinitialize espcamera I2C use properly. #11108. Thanks @dhalbert.
• Fixed GATT discovery failures: build Python objects on main task, not BLE task. #11104. Thanks @dhalbert.
• Fix I2SOut. #11083. Thanks @dhalbert.
• Wait for access point IP address to be valid. #11082. Thanks @dhalbert.
• Fixed ESP-NOW regression. #11075. Thanks @dhalbert.

i.MX

Nordic

renode

RP2xxx

• Fix USB host failures. #11130, #11120, #11117, #11114. Thanks @mikeysklar.
• Check builds for use of flash by core 1 USB host code. #11115. Thanks @mikeysklar.
• Implement sdioio. #11090. Thanks @FoamyGuy.
• Enable audiodelays, audiofilters, and audiofreeverb. #11074. Thanks @FoamyGuy.

SAMx

SiLabs

Spresense

STM

Zephyr

Individual boards

• LILYGO T-Dongle S3: invert brightness sense. #11092. Thanks @dhalbert.

Documentation changes

• Fix doubled backslashes in settings.toml documentation. #11119. Thanks @dhalbert.

Build and infrastructure changes

• fix CIRCUITPY_* flags that should be #if, not #ifdef. #11069. Thanks @dhalbert.

Translation additions and improvements

• Use sort-by-file instead of deprecated --sort-outputfor xgettext and mergemsg. #11107. Thanks @dhalbert.
• Translations
  • @LydoriaChan (Turkish)
  • @lydorianP (Turkish)

New boards

• PCBCupid GLYPH C3. #11096. Thanks @pcbcupid.
• PCBCupid GLYPH C6. #11100. Thanks @pcbcupid.
• PCBCupid GLYPH H2. #11101. Thanks @pcbcupid.

Known issues

• See https://github.com/adafruit/circuitpython/issues for other issues, including issues still to be addressed for:
  • 10.2.x
  • 10.3.0
  • 10.x.x
  • 11.0.0
  • long term

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.

This is CircuitPython 10.3.0-alpha.3, an alpha release for 10.3.0. Further features, changes, and bug fixes will be added before the final release of 10.3.0.

Highlights of this release

• Add usb_audio.USBMicrophone and usb_audio.USBSpeaker, which provide audio source and sink USB devices.
• Add audiospeed.Resampler.
• Add audio_i2sin input audio stream; supported only on Espressif and RP2xxx.
• Fix Espressif camera support regression.
• Fix several Espressif BLE bugs.
• Other bug fixes.

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-C2, ESP32-C3, ESP32-C6, ESP32-C61, ESP32-H2, ESP32-S2, ESP32-S3
• 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:

• analog: Analog Devices MAX32690
• broadcom: Raspberry Pi boards such as RPi 4, RPi Zero 2W
• espressif: ESP32-P4
• litex: fomu
• mimxrt10xx: NXP i.MX RT10xxx
• renode: hardware simulator
• silabs: Silicon Labs MG24 family
• stm: ST non-STM32F4 chip families
• zephyr: multiplatform RTOS, running on multiple chip families

Changes since 10.3.0-alpha.2

Fixes and enhancements

• Add audio_i2sin on Espressif and RP2xxx. It can act as an audio stream like other audio sources. #11064, #10990. Thanks @FoamyGuy.
• Add usb_audio.USBSpeaker. #11062. Thanks @FoamyGuy.
• Add usb_audio.USBMicrophone. #11058. Thanks @FoamyGuy.
• Add audiospeed.Resampler. #11057. Thanks @relic-se.
• Allow using an I/O expander pin or a DigitalInOut for the sdcardio.SDCard chip-select pin. #11053. Thanks @bablokb.
• Fix dotclockframebuffer GPIO expander pin validation. #11028. Thanks @makermelissa.
• Add mask arg to bitmaptools.alphablend(). #11027. Thanks @makermelissa.
• Fix stereo signal processing in audiofilters.Filter. #11025. Thanks @relic-se.
• Fix audiospeed.SpeedChanger. #11022. Thanks @todbot.
• Fix filesystem incorrectly reported as read-only for web and BLE workflows. #11048. Thanks @makermelissa.
• Return HTTP 409 instead of 500 on web workflow when filesytem is read-only. #11017. Thanks @makermelissa.
• Simplify startup message printing to fix suppressing messages from boot.py on the display. #11010. Thanks @dhalbert.
• Turn on __delattr__() and __setattr__() on most boards. #11007. Thanks @dhalbert.

Port and board-specific changes

Analog Devices

Broadcom

Espressif

• Fix camera support. #11059. Thanks @dhalbert.
• Turn on audiobusio.PDMIn on ESP32. Improve PDMIn documentation and compile options. #11056. Thanks @dhalbert.
• Fix crashes due to BLE reset bug on startup. #11051. Thanks @dhalbert.
• Fix slow BLE discovery. #11050. Thanks @dhalbert.
• Use a more recent cmake version. #11043. Thanks @bablokb.
• Validate arg for ParallelBus to prevent crashes. #11041. Thanks @dhalbert.
• Fix BLE advertising duration. Return bleio.adapter.connected as True earlier. #11036. Thanks @dhalbert.
• Remove obsolete lwip workaround. #11016. Thanks @dhalbert.

i.MX

Nordic

renode

RP2xxx

• Use irq_shared_handler() instead of isr_dma_0(). #11054. Thanks @dhalbert.
• Fix uses of PICO_RP2040 and PICO_RP2350 compile macros. #11019, #11014. Thanks @dhalbert.
• Switch back to using upstream Pico-PIO-USB library. #11015. Thanks @dhalbert.
• Turn off picodvi on boards without available pins. #11008. Thanks @dhalbert.

SAMx

SiLabs

Spresense

STM

Zephyr

• Pin protobuf version to prevent build issues. #11045. Thanks @tannewt.
• Update Zephyr version to post-4.4.0. #11011. Thanks @tannewt.

Individual boards

• senseBox MCU Eye: update name, pins, and flash. #11063. Thanks @sensebox.

Documentation changes

• Improve deep sleep and displayio.release_displays() documentation. #11038. Thanks @dhalbert.

Build and infrastructure changes

• Prevent duplicate builds on PR's and releases. #11046. Thanks @dhalbert.
• Fix incorrect compressed translation qstr ids. #11037. Thanks @dhalbert.

Translation additions and improvements

New boards

• PCBCupid Glyph Mini 2040. #11034. Thanks @pcbcupid.
• PCBCupid GLYPH S3. #11042. Thanks @pcbcupid.
• Waveshare ESP32-S3-Tiny-N8R8. #11033. Thanks @stolen.

Known issues

• Native-code .mpy files are not working. This capability is currently enabled only on the winterbloom_sol board.
• See https://github.com/adafruit/circuitpython/issues for other issues, including issues still to be addressed for:
  • 10.2.x
  • 10.3.0
  • 10.x.x
  • 11.0.0
  • long term

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.

This is CircuitPython 10.3.0-alpha.2, an alpha release for 10.3.0. Further features, changes, and bug fixes will be added before the final release of 10.3.0.

Highlights of this release

• Fix crashes on certain boards with integral displays.
• Adafruit MagTag 2025: improve display quality and support new display variant.
• Add CIRCUITPY_SDCARD_USB to settings.toml to control visibility of a mounted SD card on USB.
• Support float values in settings.toml.
• Report USB MSC drives as removable media to the host.
• Update ESP-IDF to v6.0.1.
• Fix audiomixer.Mixer regressions on SAMx5x.
• STM: support audio.AudioOut, using DAC.

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-C2, ESP32-C3, ESP32-C6, ESP32-C61, ESP32-H2, ESP32-S2, ESP32-S3
• 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:

• analog: Analog Devices MAX32690
• broadcom: Raspberry Pi boards such as RPi 4, RPi Zero 2W
• espressif: , ESP32-P4
• litex: fomu
• mimxrt10xx: NXP i.MX RT10xxx
• renode: hardware simulator
• silabs: Silicon Labs MG24 family
• stm: ST non-STM32F4 chip families
• zephyr: multiplatform RTOS, running on multiple chip families

Changes since 10.3.0-alpha.1

Fixes and enhancements

• Adafruit MagTag 2025: improve display quality. #11003, #11001. Thanks @mikeysklar.
• Update frozen libraries. #10998. Thanks @dhalbert.
• Fix crashes on boards with FourWire displays with no reset pin. #10997, #10995. Thanks @dhalbert.
• Add CIRCUITPY_SDCARD_USB to settings.toml to control SD card USB presentation. #10996. Thanks @dhalbert.
• Add support for float values in settings.toml. #10975. Thanks @dhalbert.
• Report USB MSC drives as removable media to the host. #10967. Thanks @mikeysklar.

Port and board-specific changes

Analog Devices

Broadcom

Espressif

• Fix WiFi/BLE crashes after ESP-IDF v6.0.1 upgrade. #11004. Thanks @tannewt.
• Preserve alarm.sleep_memory across software resets. #10989, #10899. Thanks @lzr
• Support ESP32-P4 V1. #10986. Thanks @tannewt.
• Update ESP-IDF to v6.0.1. #10922. Thanks @tannewt.

i.MX

Nordic

renode

RP2

SAMx

• Fix audiomixer.Mixer regressions on SAMx5x. #10906. Thanks @relic-se.

SiLabs

Spresense

STM

• Support audio.AudioOut, using DAC. #10976. Thanks @ChrisNourse.

Zephyr

Individual boards

• Adafruit MagTag 2025: improve display quality, support new display variant. #11003, #10992, #10987. Thanks @mikeysklar.
• Unexpected Maker S3 D series: add board.ANTENNA_SWITCH (board.IO41). #10984. Thanks @JonNelson.

Documentation changes

Build and infrastructure changes

Translation additions and improvements

• Thanks for translations:
  • @cyphra (Spanish)

New boards

• Adafruit P4GPIO. #10986. Thanks @tannewt.
• Espressif ESP32-P4X-Function-EV. #11004. Thanks @tannewt.
• NHB Systems JL401-S3. #10997, #10977. Thanks @NHBSystems.

Known issues

• The CIRCUITPY drive is not working on at least some STM32 boards.
• Native-code .mpy files are not working. This capability is currently enabled only on the winterbloom_sol board.
• See https://github.com/adafruit/circuitpython/issues for other issues, including issues still to be addressed for:
  • 10.2.x
  • 10.x.x
  • 11.0.0
  • long term

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.

This is CircuitPython 10.2.1, a bugfix revision of CircuitPython, and is a new stable release.

Highlights of this release

• Fix crashes on certain boards with integral displays.
• Adafruit MagTag 2025: improve display quality and support new display variant.

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-C2, ESP32-C3, ESP32-C6, ESP32-C61, ESP32-H2, ESP32-S2, ESP32-S3
• 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:

• analog: Analog Devices MAX32690
• broadcom: Raspberry Pi boards such as RPi 4, RPi Zero 2W
• espressif: , ESP32-P4
• litex: fomu
• mimxrt10xx: NXP i.MX RT10xxx
• renode: hardware simulator
• silabs: Silicon Labs MG24 family
• stm: ST non-STM32F4 chip families
• zephyr: multiplatform RTOS, running on multiple chip families

Changes since 10.2.0

Fixes and enhancements

• Update frozen modules. #11001. Thanks @dhalbert.
• Fix crashes on boards with FourWire displays with no reset pin. #10995. Thanks @dhalbert.

Port and board-specific changes

Analog Devices

Broadcom

Espressif

i.MX

Nordic

renode

RP2

SAMx

SiLabs

Spresense

STM

Zephyr

Individual boards

• Adafruit MagTag 2025: improve display quality, support new display variant. #11002, #11000,. Thanks @mikeysklar.

Documentation changes

Build and infrastructure changes

Translation additions and improvements

New boards

• NHB Systems JL401-S3. #10977. Thanks @NHBSystems.

Known issues

• ESP32-C6 has problems.
• The CIRCUITPY drive is not working on at least some STM32 boards.
• Native-code .mpy files are not working. This capability is currently enabled only on the winterbloom_sol board.
• See https://github.com/adafruit/circuitpython/issues for other issues, including issues still to be addressed for:
  • 10.2.x
  • 10.x.x
  • 11.0.0
  • long term

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.

This is CircuitPython 10.3.0-alpha.1, an alpha release for 10.2.0. Further features, changes, and bug fixes will be added before the final release of 10.3.0.

Highlights of this release

• Improve SD card USB presentation on macOS.
• Prefer foo.py over foo/ package when importing, like CPython.
• Pin fixes.
• Enable gifio and `storage in Zephyr port.

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-C2, ESP32-C3, ESP32-C6, ESP32-C61, ESP32-H2, ESP32-S2, ESP32-S3
• 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:

• analog: Analog Devices MAX32690
• broadcom: Raspberry Pi boards such as RPi 4, RPi Zero 2W
• espressif: , ESP32-P4
• litex: fomu
• mimxrt10xx: NXP i.MX RT10xxx
• renode: hardware simulator
• silabs: Silicon Labs MG24 family
• stm: ST non-STM32F4 chip families
• zephyr: multiplatform RTOS, running on multiple chip families

Changes since 10.2.0

Fixes and enhancements

• • Prefer foo.py over foo/ package when importing, like CPython. Conforms to CPython behavior. #10951. Thanks @tannewt.
• Automount SD card earlier to make USB SD card access work properly on macoS. #10963. Thanks @mikeysklar.

Port and board-specific changes

Analog Devices

Broadcom

Espressif

i.MX

Nordic

renode

RP2

SAMx

SiLabs

Spresense

STM

Zephyr

• Enable gifio and storage. #10970. Thanks @FoamyGuy.

Individual boards

• Waveshare ESP32-S3 Matrix: fix pin name typo. #10971. Thanks @kylefmohr.

Documentation changes

Build and infrastructure changes

Translation additions and improvements

• Thanks for translations:
  • @andibing (English - UK)

New boards

Known issues

• ESP32-C6 networking is not working well.
• The CIRCUITPY drive is not working on at least some STM32 boards.
• Native-code .mpy files are not working. This capability is currently enabled only on the winterbloom_sol board.
• See https://github.com/adafruit/circuitpython/issues for other issues, including issues still to be addressed for:
  • 10.2.x
  • 10.x.x
  • 11.0.0
  • long term

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.

This is CircuitPython 10.2.0, a minor revision of CircuitPython, and is a new stable release.

Highlights of this release

• New audiotools.SpeedChanger.
• New qspibus support for displayio.
• Stability improvements to USB SD card handling.
• Merge of MicroPython v1.27.
• Update to ESP-IDF v5.5.3.
• Many additions to the Zephyr port.
• Simulated hardware testing is now being done in the Zephyr port.

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-C2, ESP32-C3, ESP32-C6, ESP32-C61, ESP32-H2, ESP32-S2, ESP32-S3
• 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:

• analog: Analog Devices MAX32690
• broadcom: Raspberry Pi boards such as RPi 4, RPi Zero 2W
• espressif: , ESP32-P4
• litex: fomu
• mimxrt10xx: NXP i.MX RT10xxx
• renode: hardware simulator
• silabs: Silicon Labs MG24 family
• stm: ST non-STM32F4 chip families
• zephyr: multiplatform RTOS, running on multiple chip families

Changes since 10.1.4 and 10.2.0-alpha.1

Fixes and enhancements

• Fix web workflow background callback handling. #10966. Thanks @dhalbert.
• Fix sdcardio.SDCard regression that failed to init some cards. #10956. Thanks @dhalbert and @bablokb.
• Update frozen libraries. #10945, #10853, Thanks @dhalbert and @FoamyGuy.
• Merge MicroPython v1.27 into CircuitPython. #10931. Thanks @dhalbert.
• Fix palette length validation in _stage. #10904. Thanks @deshipu.
• Add audiotools.SpeedChanger. #10900. Thanks @todbot.
• Add mcp4822 SPI DAC support. #10895. Thanks @todbot.
• Improve USB SD presentation, sdcardio implementation, displayio bus sharing. #10887. Thanks @dhalbert.
• Add arg validations in various bitmaptools methods. #10884. Thanks @FoamyGuy.
• Merge 10.1.x fixes. #10877, #10839. Thanks @dhalbert.
• Fix handling of full-width glyphs in lvfontio. #10865. Thanks @FoamyGuy.
• Added displayio qspibus support. #10844. Thanks @ppsx.

Port and board-specific changes

Analog Devices

Broadcom

Espressif

• Change USB task priority to be the same as the CircuitPython task. #10887. Thanks @dhalbert.
• Fix BLE startup crash. #10858. Thanks @tannewt.
• Update to ESP-IDF 5.5.3. #10840. Thanks @tannewt.

i.MX

Nordic

renode

RP2

• Fix i2ctarget bugs. #10933. Thanks @FoamyGuy.
• Fix i2ctarget start bug. #10474. Thanks @MarkEbrahim.

SAMx

SiLabs

Spresense

STM

• Move SPI deinit code to prevent crash. #10926. Thanks @ChrisNourse.

Zephyr

• Fix flash size on Feather RP240. #10960. Thanks @FoamyGuy.
• Enable jpegio, getpass, adafruit_bus_device, hashlib, zlib, aesio, msgpack. #10952, #10949, #10943, #10939, #10932, #10927. Thanks @FoamyGuy.
• Add nvm support. #10918. Thanks @tannewt.
• Add Adafruit Feather RP240. #10925. Thanks @FoamyGuy.
• Add Adafruit Feather nRF2840 Sense. #10923. Thanks @tannewt.
• Add Raspberry Pi Pico, Pico W, Pico2, Pico2 W. #10917. Thanks @tannewt.
• add audiobusio.I2SOut support. #10916. Thanks @tannewt.
• Zephyr port and build fixes. #10912, #10911, #10863, #10860, #10859. Thanks @tannewt.
• Allow building and uploading native_sim .exe. #10897. Thanks @tannewt.
• Add heap statistics tracking to native_sim. #10869. Thanks @tannewt.
• Add zephyr_display to support fixed Zephyr displays. #10868. Thanks @tannewt.
• Implement _bleio scanning, advertising, connect, and disconnect. #10862, #10833. Thanks @tannewt.
• Add TCP neworking support. #10847. Thanks @tannewt.
• Test simulated hardware using perfetto traces. #10846. Thanks @tannewt.
• Handle time simulation without using yields. #10834. Thanks @tannewt.

Individual boards

• Adafruit QT Py ESP32-S3 4/2 and 8/0: reduce default WiFi power to 15 dBm. #10921. Thanks @jesseadams.
• Cytron Maker Pi RP2040: add GP29 pin definitions. #10893. Thanks @CytronTechnologies.
• uGame S3: slow down SPI to avoid display glitches. #10837. Thanks @deshipu.

Documentation changes

• Fix typo in tim.monotonic_ns(). #10950. Thanks @tannewt.
• Explain SD card initialization more thoroughly. #10962, #10947. Thanks @mikeysklar.
• Correct return type in busio.I2C.probe(). #10891. Thanks @FoamyGuy.

Build and infrastructure changes

• Update CI actions to Node.24 versions. #10910. Thanks @dhalbert.
• Fix ReadTheDocs build warnings. #10907. Thanks @dhalbert.
• Add support for user-supplied build configuration files: user_pre_mpconfigport.mk, user_post_mpconfigport.mk, user_post_circuitpy_defns.mk. #10817. Thanks @bablokb.

Translation additions and improvements

New boards

• Pimoroni Badger2350. #10929. Thanks @bablokb.
• Pimoroni Explorer RP2350. #10778. Thanks @tyeth.
• TinyCircuits Thumby and Thumby Color. #10851, #10303. Thanks @tannewt.
• Waveshare ESP32-S# Touch AMOLED 2.41". #10844. Thanks @ppsx.
• WeAct Studio RP2350B Core. #10646. Thanks @cvmanjoo.
• Xteink X4. #10873. Thanks @BlitzCityDIY.

Known issues

• ESP32-C6 networking is not working well.
• The CIRCUITPY drive is not working on at least some STM32 boards.
• Native-code .mpy files are not working. This capability is currently enabled only on the winterbloom_sol board.
• See https://github.com/adafruit/circuitpython/issues for other issues, including issues still to be addressed for:
  • 10.2.x
  • 10.x.x
  • 11.0.0
  • long term

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.