CircuitPython 4.0.0 Beta 3 !

This is a beta build of 4.0.0. There are still issues to fix before stable and the new APIs may evolve a bit more. Please use the latest 3.x stable release when first starting with CircuitPython. It is stable.

When you find a bug please check the current known issues and file an issue if something isn't already known.

4.0.0

4.0.0 is the latest major revision of CircuitPython. It features:

• a port to the Nordic nRF52840 microcontroller, including support as a BLE beacon or peripheral (bleio)
• extensive new support for pixel-based displays (displayio)
• USB MIDI support
• messages translated into multiple languages

Installation

To install follow the instructions in our new 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).

Most builds are available as both UF2 and bin files here along with test builds.

New Features, Updates, and Fixes since Beta 2

• Check for length too long on Python sequence multiply, thanks to @tannewt.
• rotaryio added to nrf port, thanks to @nickzoic.
• ENOSPC error now has numan-readable text, thanks to @cpforbes.
• USB MIDI fixes, thanks to @cpforbes.
• Set __file__ for main source code file, thanks to @cpforbes.
• Space-saving and build fixes, thanks to @debrouxl, for use with a specialized build for a TI calculator accessory.
• German translation improvements, thanks to @Tasm-Devil.
• Rework of translation builds and output, to reduce merge difficulties, thanks to @tannewt.
• Many displayio additions, improvements, and fixes, thanks to @tannewt.
• displayio and PyPortal board fixes and improvements, thanks to @TG-Techie.
• Fix atmel-samd UART implementation, thanks to @dhalbert.
• Additional re (was ure) functionality, thanks to @notro.
• Entering safe mode via slow double click fixed on SAMD51, thanks to @tannewt.
• The long list of links to CircuitPython driver documentation is now a part of the CircuitPython Bundle instead of being part of the circuitpython repo. Thanks to @sommersoft.
• Build options were extensively refactored, allowing features to be turned on and off more easily. The atmel-samd and nrf ports were also made much more similar, and share more common settings now. Thanks to @dhalbert.
• Support print(..., flush=True), thanks to @tannewt.
• Add support for 1-bit (monochrome), 8-bit (indexed and grayscale), 16-bit (565), and 32-bit (ARGB) pixel sizes in displayio.OnDiskBitmap, thanks to @siddacious.
• bleio bug fixes, thanks to @dhalbert.
• Ability to allow filesystem writes from both USB and internal CircuitPython (dangerous!), thanks to @tannewt, with inspiration from @ladyada.
• Refactoring of timer code into `samd-peripherals, thanks to @sommersoft.
• Add .height and .width properties to Display, thanks to @penguindustin.
• 'displayio` refresh fixes, thanks to @dhalbert.
• PWMOut fixes on atmel-samd, thanks to @dhalbert, and thanks to @kevinjwalters for discovering the problem and testing the fix.
• frequencyio.FrequencyIn frequency measurement capability on atmel-samd ports, thanks to @sommersoft.

New Boards

• SAM32. Thanks to @maholli.

Breaking Changes from 3.x!

• ure, ujson, and uerrno renamed to re, json, and errno to reflect that they are subsets of the CPython library modules. Thanks to @dhalbert.

• busio.UART breaking changes to match PySerial. Thanks to @dhalbert
  • busio.UART constructor timeout parameter is now in seconds instead of milliseconds.
  • UART.readinto(buf) now does not allow an optional length parameter UART.readinto(buf, len).
  • UART.write(...) no longer allows strings to be written. The bytes written must be bytes or bytearray or an array.array.
• framebuf has been removed. displayio is its replacement, and will be enhanced after 4.0 to include framebuf's functionality. Thanks to @tannewt.
• Improve struct compatibility with CPython by enforcing stricter types. This may break your code! Thanks to @dhalbert.

Thanks

Thank you to all who used, tested, contributed, helped out, and participated on GitHub and/or Discord:
@adafruit, @anecdata, @arofarn, @arturo182, @ATMakersBill, @brennen, @brentru, @bwshockley, @C47D, @CarlFK, @carlosperate, @caternuson, @CedarGroveStudios, @chalei, @charlesbunaford, @cpforbes, @dastels, @deshipu, @dhalbert, @dsiee, @edspark, @eighthree, @furlaneto, @gcvasconcelos, @glennrub, @gpshead, @hathach, @iraytrace, @Jahor, @jasonp, @jepler, @jay Doscher, @jerryneedell, @jimblom, @johnpark, @JoshuaLowe1002, @Uanita, @kattni, @kevinjwalters, @klardotsh, @Klowner, @ladyada, @larsks, @madbodger, @maholli, @Makdaam, @makermelissa, @mattyt, @mchobby, @microbuilder, @Mikebarela, @mr. Certainly, @mrmcwethy, @nickzoic, @notro, @OldCrow, @penguindustin, @PhredFL, @platipo, @Retoc, @rhooper, @sabas1080, @sajattack, @sajattack, @saspa, @schmarty, @Senuros, @ShawnHymel, @siddacious, @sommersoft, @SouthernDragon, @TangoJuliett, @tannewt, @Tasm-Devil, @TG-Techie, @uhrheber, @urish, @vgoodwinv, @xpecex, @yeyeto2788, and surely more we have missed. Join us on the Discord chat to collaborate.

Documentation

Documentation is available in readthedocs.io.

Here are all the changes since 4.0.0-beta.2.
Here are all the changes since 3.1.2.

This release is based on MicroPython 1.9.4 @25ae98f. Support upstream MicroPython by purchasing a PyBoard (from Adafruit here).

Troubleshooting

Check out this guide for info on common problems with CircuitPython. If you are still having, then post to the Adafruit Support Forums and join Discord.

CircuitPython 4.0.0 Beta 2!

This is a beta build of 4.0.0. There are still issues to fix before stable and the new APIs may evolve a bit more. Please use the latest 3.x stable release when first starting with CircuitPython. It is stable.

When you find a bug please check the current known issues and file an issue if something isn't already known.

4.0.0

4.0.0 is the latest major revision of CircuitPython and features support for the nRF52840 BLE chipset and translated messages.

Installation

To install follow the instructions in our new 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).

Most builds are available as both UF2 and bin files here along with test builds.

New Features, Updates, and Fixes since Beta 1

• nrf: Add touchio support to nRF52840 using a 1mOhm drain resistor. Thanks to @nickzoic
• nrf: Improve USB and BLE coexistence. Thanks to @hathach
• displayio changes. Thanks to @tannewt
  • Adds serial output to displays when they are available.
  • Replaces Sprite with TileGrid which is more generic.
  • Display now manages the backlight brightness. To change it manually do display.auto_brightness = False and then set display.brightness with a value 0 to 1.0.
  • Add support for display rotation.
• Enables FATFS fast seek to slightly improve file read times. Thanks to @tannewt

New Boards

• SparkFun LumiDrive. Thanks to @edspark
• SparkFun Redboard Turbo. Thanks to @edspark

Breaking Changes from 3.x!

• busio.UART breaking changes to match PySerial. Thanks to @dhalbert
  • busio.UART constructor timeout parameter is now in seconds instead of milliseconds
  • UART.readinto(buf) now does not allow an optional length parameter UART.readinto(buf, len)
  • UART.write(...) no longer allows strings to be written. The bytes written must be bytes or bytearray or an array.array.
• framebuf has been removed. displayio is its replacement, and will be enhanced after 4.0 to include framebuf's functionality.
• Improve struct compatibility with CPython by enforcing stricter types. This may break your code! Thanks to @dhalbert

Known Issues

None

Thanks

Thank you to all who used, tested, contributed, helped out, and participated on GitHub and/or Discord:
@ladyada, @dhalbert, @tannewt, @kattni, @microbuilder, @hathach, @arturo182, @nickzoic, @glennrub, @siddacious, @deshipu, @sommersoft, @jerryneedell, @brentru, @caternuson, @jepler, @urish, @sajattack, @notro, @Jahor, @Makdaam, @mrmcwethy, @jepler, @notro, @mattyt, @furlaneto, @ATMakersBill, @Klowner, @klardotsh, @C47D, @carlosperate, @platipo, @xpecex, @gcvasconcelos, @saspa, @uhrheber, @nickzoic, @sabas1080, @sajattack, @JoshuaLowe1002, @Senuros, @mchobby, @Retoc, @CedarGroveStudios, @bwshockley, @yeyeto2788, @jimblom, @rhooper, @ShawnHymel, @TG-Techie, @eighthree, @arofarn, @chalei, @vgoodwinv, @gpshead, @dsiee, @Tasm-Devil, @larsks, @CarlFK, @edspark and surely more we have missed. Join us on the Discord chat to collaborate.

Documentation

Documentation is available in readthedocs.io.

Here are all the changes since 4.0.0-beta.1.
Here are all the changes since 3.1.2.

This release is based on MicroPython 1.9.4 @25ae98f. Support upstream MicroPython by purchasing a PyBoard (from Adafruit here).

Troubleshooting

Check out this guide for info on common problems with CircuitPython. If you are still having, then post to the Adafruit Support Forums and join Discord.

CircuitPython 4.0.0 Beta 1

This release includes a number of bug fixes to bleio and displayio since Beta 0.

This is a beta build of 4.0.0. There are still issues to fix before stable and the new APIs may evolve a bit more. Please use the latest 3.x stable release when first starting with CircuitPython. It is stable.

When you find a bug please check the current known issues and file an issue if something isn't already known.

4.0.0

4.0.0 is the latest major revision of CircuitPython and features support for the nRF52840 BLE chipset and translated messages.

Installation

To install follow the instructions in our new 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).

Most builds are available as both UF2 and bin files here along with test builds.

New Features, Updates, and Fixes since Beta 0

• bleio fixes that make it work with newer iOS devices and Android. Thanks to @dhalbert
• Fix bleio docs. Thanks to @dhalbert
• Fix time.struct_time() incorrect argument checking. Thanks to @jerryneedell
• Fix color computation in displayio.Palette and make init code more USB friendly. Thanks to @tannewt
• Translation updates:
  • German thanks to @Tasm-Devil

New Boards

• SparkFun SAMD21 Dev. Thanks to @ShawnHymel

Breaking Changes from 3.x!

• busio.UART breaking changes to match PySerial. Thanks to @dhalbert
  • busio.UART constructor timeout parameter is now in seconds instead of milliseconds
  • UART.readinto(buf) now does not allow an optional length parameter UART.readinto(buf, len)
  • UART.write(...) no longer allows strings to be written. The bytes written must be bytes or bytearray or an array.array.
• framebuf has been removed. displayio is its replacement, and will be enhanced after 4.0 to include framebuf's functionality.
• Improve struct compatibility with CPython by enforcing stricter types. This may break your code! Thanks to @dhalbert

Known Issues

Thanks

Thank you to all who used, tested, contributed, helped out, and participated on GitHub and/or Discord:
@ladyada, @dhalbert, @tannewt, @kattni, @microbuilder, @hathach, @arturo182, @nickzoic, @glennrub, @siddacious, @deshipu, @sommersoft, @jerryneedell, @brentru, @caternuson, @jepler, @urish, @sajattack, @notro, @Jahor, @Makdaam, @mrmcwethy, @jepler, @notro, @mattyt, @furlaneto, @ATMakersBill, @Klowner, @klardotsh, @C47D, @carlosperate, @platipo, @xpecex, @gcvasconcelos, @saspa, @uhrheber, @nickzoic, @sabas1080, @sajattack, @JoshuaLowe1002, @Senuros, @mchobby, @Retoc, @CedarGroveStudios, @bwshockley, @yeyeto2788, @jimblom, @rhooper, @ShawnHymel, @TG-Techie, @eighthree, @arofarn, @chalei, @vgoodwinv, @gpshead, @dsiee, @Tasm-Devil, @larsks, @CarlFK and surely more we have missed. Join us on the Discord chat to collaborate.

Documentation

Documentation is available in readthedocs.io.

Here are all the changes since 4.0.0-beta.0.
Here are all the changes since 3.1.2.

This release is based on MicroPython 1.9.4 @25ae98f. Support upstream MicroPython by purchasing a PyBoard (from Adafruit here).

Troubleshooting

Check out this guide for info on common problems with CircuitPython. If you are still having, then post to the Adafruit Support Forums and join Discord.

CircuitPython 4.0.0 Beta 0!

This release includes a number of excellent enhancements since Alpha 5 including many bleio and displayio improvements.

This is the first beta build of 4.0.0. There are still issues to fix before stable and the new APIs may evolve a bit more. Please use the latest 3.x stable release when first starting with CircuitPython. It is stable.

When you find a bug please check the current known issues and file an issue if something isn't already known.

4.0.0

4.0.0 is the latest major revision of CircuitPython and features support for the nRF52840 BLE chipset and translated messages.

Installation

To install follow the instructions in our new 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).

Most builds are available as both UF2 and bin files here along with test builds.

New Features, Updates, and Fixes since Alpha 5

• displayio improvements. Thanks to @tannewt
  • Dynamic displays are now supported.
  • 8 bit parallel display bus is now supported.
  • Shapes are now supported with displayio.Shape. (Meant to be subclassed.)
  • Hallowing display now uses board.SPI() so user can use it as well.
• bleio has been rewritten to work in conjunction with Adafruit_CircuitPython_BLE. Together they now support the standard Nordic BLE UART Service. Various kinds of advertising beacons are supported as well. Also see the new library Adafruit_CircuitPython_Bluefruit, which supports communication using the Adafruit Bluefruit LE Connect app. Thanks to @dhalbert
• Add USB Midi support. Thanks to @tannewt
• Add _pixelbuf module to speed up RGBW pixels like NeoPixel and DotStar. Thanks to @rhooper
• nrf: Add PulseIn support. Thanks to @hathach
• nrf: Remove framebuf. displayio is supported. Thanks to @jerryneedell
• atmel-samd: Fix the I2C on Grand Central M4 Express
• Improve struct compatibility with CPython by enforcing stricter types. This may break your code! Thanks to @dhalbert
• Add x support to struct unpack. Thanks to @dhalbert.
• Add .height and .width to OnDiskBitmap. Thanks to @siddacious
• Add support for subclassing native classes that take kwargs into __init__. Thanks to @tannewt
• README improvements. Thanks to @kattni
• New Bahasa Indonesia (ID) translation thanks to @chalei
• Translation updates:
  • German thanks to @Tasm-Devil
  • Spanish thanks to @yeyeto2788,
  • French thanks to @arofarn
  • Tagalog thanks to @eighthree

New Boards

• SparkFun nRF52840 Mini. Thanks to @jimblom.
• Arduino MKR Zero. Thanks to @ShawnHymel
• SparkFun SAMD21 Mini. Thanks to @ShawnHymel
• Datalore IP M4. Thanks to @TG-Techie.
• MakerDiary nRF52840 MDK USB Dongle. Thanks to @gpshead.

Breaking Changes from 3.x!

• busio.UART breaking changes to match PySerial. Thanks to @dhalbert
  • busio.UART constructor timeout parameter is now in seconds instead of milliseconds
  • UART.readinto(buf) now does not allow an optional length parameter UART.readinto(buf, len)
  • UART.write(...) no longer allows strings to be written. The bytes written must be bytes or bytearray or an array.array.
• framebuf has been removed. displayio is its replacement, and will be enhanced after 4.0 to include framebuf's functionality.
• Improve struct compatibility with CPython by enforcing stricter types. This may break your code! Thanks to @dhalbert

Known Issues

• Some documentation in the bleio module is outdated and incorrect.
• bleio services don't seem to work properly on some newer models of iOS devices, and perhaps on some Android devices as well. iPhones 6s and before seem to work, but we have had trouble with iPhone 7. A 2018 iPad also does not work. The problems seem to be due to hardware rather than iOS versions.

Thanks

Thank you to all who used, tested, contributed, helped out, and participated on GitHub and/or Discord:
@ladyada, @dhalbert, @tannewt, @kattni, @microbuilder, @hathach, @arturo182, @nickzoic, @glennrub, @siddacious, @deshipu, @sommersoft, @jerryneedell, @brentru, @caternuson, @jepler, @urish, @sajattack, @notro, @Jahor, @Makdaam, @mrmcwethy, @jepler, @notro, @mattyt, @furlaneto, @ATMakersBill, @Klowner, @klardotsh, @C47D, @carlosperate, @platipo, @xpecex, @gcvasconcelos, @saspa, @uhrheber, @nickzoic, @sabas1080, @sajattack, @JoshuaLowe1002, @Senuros, @mchobby, @Retoc, @CedarGroveStudios, @bwshockley, @yeyeto2788, @jimblom, @rhooper, @ShawnHymel, @TG-Techie, @eighthree, @arofarn, @chalei, @vgoodwinv, @gpshead, @dsiee, @Tasm-Devil, @larsks, @CarlFK and surely more we have missed. Join us on the Discord chat to collaborate.

Documentation

Documentation is available in readthedocs.io.

Here are all the changes since 4.0.0-alpha.5.
Here are all the changes since 3.1.2.

This release is based on MicroPython 1.9.4 @25ae98f. Support upstream MicroPython by purchasing a PyBoard (from Adafruit here).

Troubleshooting

Check out this guide for info on common problems with CircuitPython. If you are still having, then post to the Adafruit Support Forums and join Discord.

CircuitPython 3.1.2

Changes since 3.1.1

• All frozen libraries have been updated to their latest versions as of 2019-01-05.
• Added runtime.serial_bytes_available. Returns True if any bytes are available to read on the USB serial input. Allows for polling to see whether to call the built-in input() or wait. (read-only). Thanks to @ATMakersBill.
• nRF52840-related builds were removed from 3.x as of 3.1.2 because certain software downloads that 3.x depends on were removed from Nordic's website. It is no longer possible to build these on the 3.x branch. But see the 4.0 (master) branch for viable and better support for nRF52840. Note also that nRF52832 builds from commits before 3.1.2 will no longer build due to changed download locations on the Nordic website. Thanks to @dhalbert.

Installation

To install follow the instructions in our new 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).

All builds are available as both UF2 and bin files here along with test builds.

Documentation

Documentation is available on readthedocs.io.

Here are all the changes since 3.1.1.

This release is based on MicroPython 1.9.3. Support upstream MicroPython by purchasing a PyBoard (from Adafruit here).

mpy-cross

Pre-built mpy-cross executables are available above for MacOS, Windows, Ubuntu, and Raspbian. For MacOS, Ubuntu, and Raspbian, you must make the mpy-cross download executable by doing. Then you can compile a .py file to .mpy:

$ chmod +x mpy-cross-whatever-you-downloaded         # you only need to do this once
$ ./mpy-cross-whatever-you-downloaded yourfile.py    # this will generate yourfile.mpy

Troubleshooting

Check out this guide for info on common problems with CircuitPython. If you are still having trouble, then post to the Adafruit Support Forums and join Discord.

CircuitPython 4.0.0 Alpha 5!

This release includes a number of excellent enhancements since Alpha 3 including more reliable USB, better safe mode and Particle Mesh board support. This gets us closer to beta!

This is alpha release number 5 of 4.0.0. Alpha releases do not have the complete API from 3.x on the nRF builds and are only meant for testing. (Beta release will have the full existing API but still need work.) Please use the latest 3.x stable release when first starting with CircuitPython. It is stable.

When you find a bug please check the current known issues and file an issue if something isn't already known.

4.0.0

4.0.0 is the latest major revision of CircuitPython and features support for the nRF52840 BLE chipset and translated messages.

Installation

To install follow the instructions in our new 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).

Most builds are available as both UF2 and bin files here along with test builds.

New Features, Updates, and Fixes since Alpha 3

• busio.UART breaking changes to match PySerial. Thanks to @dhalbert
  • busio.UART constructor timeout parameter is now in seconds instead of milliseconds
  • UART.readinto(buf) now does not allow an optional length parameter UART.readinto(buf, len)
  • UART.write(...) no longer allows strings to be written. The bytes written must be bytes or bytearray or an array.array.
• Improved safe mode and added it to nRF52 boards. Thanks to @tannewt
  • 700 millisecond period at start up where a reset will go into safe mode. RGB status is yellow and the single status LED will blink three times.
  • The stack growing to overwrite the heap will reset into safe mode.
  • nRF boards will reset into safe mode on brownout.
• Fixes to USB. Thanks to @hathach and @tannewt.
• Documentation improvements. Thanks to @C47D, @sommersoft .
• Spanish translation updates. Thanks to @yeyeto2788, @C47D and @sabas1080 .

New Boards

• Mini SAM M4 Thanks to @bwshockley
• Electronic Cats' CatWAN Thanks to @sabas1080
• Particle Argon, Boron and Xenon Thanks to @tannewt

Breaking Changes from 3.x!

• busio.UART breaking changes to match PySerial. Thanks to @dhalbert
  • busio.UART constructor timeout parameter is now in seconds instead of milliseconds
  • UART.readinto(buf) now does not allow an optional length parameter UART.readinto(buf, len)
  • UART.write(...) no longer allows strings to be written. The bytes written must be bytes or bytearray or an array.array.
• framebuf has been removed. displayio is its replacement, and will be enhanced after 4.0 to include framebuf's functionality.

Known Issues

None

Thanks

Thank you to all who used, tested, contributed, helped out, and participated on GitHub and/or Discord:
@ladyada, @dhalbert, @tannewt, @kattni, @microbuilder, @hathach, @arturo182, @nickzoic, @glennrub, @siddacious, @deshipu, @sommersoft, @jerryneedell, @brentru, @caternuson, @jepler, @urish, @sajattack,, @notro, @Jahor, @Makdaam, @mrmcwethy, @jepler, @notro, @mattyt, @furlaneto, @ATMakersBill, @Klowner, @klardotsh, @C47D, @carlosperate, @platipo, @xpecex, @gcvasconcelos, @saspa, @uhrheber, @nickzoic, @sabas1080, @sajattack, @JoshuaLowe1002, @Senuros, @mchobby, @Retoc, @CedarGroveStudios, @bwshockley, @yeyeto2788 and surely more we have missed. Join us on the Discord chat to collaborate.

Documentation

Documentation is available in readthedocs.io.

Here are all the changes since 4.0.0-alpha.3.
Here are all the changes since 3.1.1.

This release is based on MicroPython 1.9.4 @25ae98f. Support upstream MicroPython by purchasing a PyBoard (from Adafruit here).

Troubleshooting

Check out this guide for info on common problems with CircuitPython. If you are still having, then post to the Adafruit Support Forums and join Discord.

Note: alpha.4 was briefly released but USB didn't work on nRF52840 so it was pulled. This release has it fixed.

CircuitPython 4.0.0 Alpha 3!

This release puts the "alpha" in our alpha releases. It features a brand-new bleio API that will definitely change over time and swaps the atmel-samd USB stack to the same one used by the nrf chips.

This is alpha release number 3 of 4.0.0. Alpha releases do not have the complete API from 3.x on the nRF builds and are only meant for testing (especially this one). (Beta release will have the full existing API but still need work.) Please use the latest 3.x stable release when first starting with CircuitPython. It is stable.

When you find a bug please check the current known issues and file an issue if something isn't already known.

4.0.0

4.0.0 is the latest major revision of CircuitPython and features support for the nRF52840 BLE chipset, display support and translated messages.

Installation

To install follow the instructions in our new 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).

Most builds are available as both UF2 and bin files here along with test builds.

New Features, Updates, and Fixes since Alpha 2

• Add bleio, the beginnings of our BLE API. Thanks @arturo182 and @dhalbert. This API will change before it is considered stable.
• Move atmel-samd to TinyUSB and refactor usb related code to be shared amongst ports. Thanks to @hathach and @tannewt. Expect to find bugs with this and please file issues for them.
• Swap the sys.path order so that frozen modules are preferred over those on the filesystem. Thanks to @dhalbert, @kattni, and @caternuson..
• Add low-level Ethernet support with network, wiznet and socket modules. Thanks to @nickzoic .
• Add .BATTERY to board for boards that allow for battery monitoring. Thanks to @sajattack.
• Add time.monotonic_ns to match the new API in Python 3.7. Thanks to @jepler
• AudioOut now preconditions the DAC at a quiescent_value to reduce audible popping when playing sound. Thanks to @tannewt, @CedarGroveStudios and @dhalbert .
• Add .channel_count and .bits_per_sample to WaveFile to make it easier to use with Mixer. Thanks to @caternuson.
• Documentation improvements thanks to @JoshuaLowe1002, @sabas1080 and @sommersoft.
• Translation updates thanks to @C47D, @sabas1080, @Senuros, @mchobby, and @Retoc.
• Update frozen modules thanks to @dhalbert, and @kattni who released many new versions of the libraries.

New Boards

• Electronic Cats' Meow Meow. Thanks to @sabas1080
• MakerDiary NRF52840 MDK. Thanks to @klardotsh
• Fennec CP32-M4. Thanks to @siddacious
• Arduino MKR1300. Thanks to @sabas1080
• Adafruit Trellis M4 Express. Thanks to @tannewt

Breaking Changes from 3.x!

• framebuf has been removed. displayio is its replacement, and will be enhanced as 4.0 progresses to include framebuf's functionality.

Known Issues

• On nRF52840, using ubluepy with first allocated busio.SPI object will cause a reset. The first SPI object created is always be the high speed 32MHz SPIM3 peripheral. To avoid this, if you need SPI, create but do not use the first SPI object, and create subsequent SPI objects to use. The second and later objects will run at a maximum of 8MHz.
• Due to a bug, the SPIM3 peripheral is not allocated. Only one SPI peripheral, running at 8MHz, is available. This accidentally works around the problem above.

Thanks

Thank you to all who used, tested, contributed, helped out, and participated on GitHub and/or Discord:
@ladyada, @dhalbert, @tannewt, @kattni, @microbuilder, @hathach, @arturo182, @nickzoic, @glennrub, @siddacious, @deshipu, @sommersoft, @jerryneedell, @brentru, @caternuson, @jepler, @urish, @sajattack,, @notro, @Jahor, @Makdaam, @mrmcwethy, @jepler, @notro, @mattyt, @furlaneto, @ATMakersBill, @Klowner, @klardotsh, @C47D, @carlosperate, @platipo, @xpecex, @gcvasconcelos, @saspa, @uhrheber, @nickzoic, @sabas1080, @sajattack, @JoshuaLowe1002, @Senuros, @mchobby, @Retoc, @CedarGroveStudios and surely more we have missed. Join us on the Discord chat to collaborate.

Documentation

Documentation is available in readthedocs.io.

Here are all the changes since 4.0.0-alpha.2.
Here are all the changes since 3.1.1.

This release is based on MicroPython 1.9.4 @25ae98f. Support upstream MicroPython by purchasing a PyBoard (from Adafruit here).

Troubleshooting

Check out this guide for info on common problems with CircuitPython. If you are still having, then post to the Adafruit Support Forums and join Discord.

CircuitPython 3.1.1

Changes since 3.0.3

• All frozen libraries have been updated to their latest versions as of 2018-11-01.

• The default value of sys.path has been changed.
  OLD:

  ['', '/', '/lib', '.frozen']
  

  NEW:

  ['', '/', '.frozen', '/lib']
  

  This change causes the frozen library of a library to be found and loaded on import, instead of any non-frozen version in /lib. Previously, to make sure the frozen version of a library was used, you had to remove that library from /lib. Whenever you updated /lib with a new library bundle, this had to be repeated.

  When frozen libraries are imported they use up much less heap space (in RAM) than compiled .mpy libraries in /lib or elsewhere. This helps prevent running out of RAM when importing several modules or allocating large amounts of storage. This was a common support issue. Thanks to @kattni for advocating for this change, to @caternuson for discussion, and @dhalbert for implementation.

  If you need to override a frozen library with a different version, simply place it in /, instead of in /lib. The version in / will be found first and will be used instead.

Note that .frozen is not a real directory. It represents all the frozen modules. You cannot list it with os.listdir().

The following builds include frozen libraries and are affected by this change: circuit_playground_express, circuit_playground_express_crickit, feather_m0_express_crickit, hallowing_m0_express, pirkey_m0.

Note: Release 3.1.0 is being skipped: the tag was created on the wrong commit. The tag has been deleted, but we're skipping to avoid confusion.

Installation

To install follow the instructions in our new 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).

All builds are available as both UF2 and bin files here along with test builds.

Documentation

Documentation is available on readthedocs.io.

Here are all the changes since 3.0.3.

This release is based on MicroPython 1.9.3. Support upstream MicroPython by purchasing a PyBoard (from Adafruit here).

mpy-cross

Pre-built mpy-cross executables are available above for MacOS, Windows, Ubuntu, and Raspbian. For MacOS, Ubuntu, and Raspian, you must make the mpy-cross download executable by doing. Then you can compile a .py file to .mpy:

$ chmod +x mpy-cross-whatever-you-downloaded         # you only need to do this once
$ ./mpy-cross-whatever-you-downloaded yourfile.py    # this will generate yourfile.mpy

Troubleshooting

Check out this guide for info on common problems with CircuitPython. If you are still having, then post to the Adafruit Support Forums and join Discord.

CircuitPython 4.0.0 Alpha 2!

4.0.0 is the latest major revision of CircuitPython and features support for the nRF52840 BLE chipset, display support and translated messages.

Alpha!

This is alpha release number 2 of 4.0.0. Alpha releases do not have the complete API from 3.x on the nRF builds and are only meant for testing. (Beta release will have the full existing API but still need work.) Please use the latest 3.x stable release when first starting with CircuitPython. It is stable.

When you find a bug please check the current known issues and file an issue if something isn't already known.

Installation

To install follow the instructions in our new 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).

Most builds are available as both UF2 and bin files here along with test builds.

New Features, Updates, and Fixes

• Add new audioio.Mixer class to provide multiple simultaneous sample playback. Thanks @tannewt.
• Add pulseio.PWMOut and pulse.PulseOut to nrf port. Thanks @dhalbert.
• Add busio.UART to nrf port. Thanks @hathach.
• Add supervisor.runtime.serial_bytes_available to see if input is available to read. Thanks @ATMakersBill.
• Add auto-reload for nrf port. Thanks @hathach.
• framebuf has been removed. displayio is its replacement, and will be enhanced as 4.0 progresses to include framebuf's functionality
• Fix storage.erase_filesystem() on nrf port. Thanks @jerryneedell.
• Enable optional support for inline assembly. Thanks @urish.
• Continued work on Spanish translation. Thanks @C47D and @carlosperate.
• Italian translation. Thanks @platipo.
• Brazilian Portuguese translation. Thanks @furlaneto, @xpecex, and @gcvasconcelos.
• Travis build improvements. Thanks @sajattack and @jepler.
• Fix bugs in nrf SPI and I2C. Thanks @dhalbert.
• Frozen libraries updated to latest released versions. Thanks @dhalbert.
• Merge latest fixes from 3.x. Thanks @tannewt.

Breaking Changes!

• framebuf has been removed. displayio is its replacement, and will be enhanced as 4.0 progresses to include framebuf's functionality

Known Issues

• On nRF52840, using ubluepy with first allocated busio.SPI object will cause a reset. The first SPI object created is always be the high speed 32MHz SPIM3 peripheral. To avoid this, if you need SPI, create but do not use the first SPI object, and create subsequent SPI objects to use. The second and later objects will run at a maximum of 8MHz.
• Due to a bug, the SPIM3 peripheral is not allocated. Only one SPI peripheral, running at 8MHz, is available. This accidentally works around the problem above.

Thanks

Thank you to all who used, tested, contributed, helped out, and participated on GitHub and/or Discord:
@ladyada, @dhalbert, @tannewt, @kattni, @microbuilder, @hathach, @arturo182, @nickzoic, @glennrub, @siddacious, @deshipu, @sommersoft, @jerryneedell, @brentru, @caternuson, @jepler, @urish, @sajattack,, @notro, @Jahor, @Makdaam, @mrmcwethy, @jepler, @notro, @mattyt, @furlaneto, @ATMakersBill, @Klowner, @klardotsh, @C47D, @carlosperate, @platipo, @xpecex, @gcvasconcelos, @saspa, @uhrheber, and surely more we have missed. Join us on the Discord chat to collaborate.

Documentation

Documentation is available in readthedocs.io.

Here are all the changes since 4.0.0-alpha.1.
Here are all the changes since 3.0.2.

This release is based on MicroPython 1.9.4 @25ae98f. Support upstream MicroPython by purchasing a PyBoard (from Adafruit here).

Troubleshooting

Check out this guide for info on common problems with CircuitPython. If you are still having, then post to the Adafruit Support Forums and join Discord.

CircuitPython 4.0.0 Alpha 1!

4.0.0 is the latest major revision of CircuitPython and features support for the nRF52840 BLE chipset, display support and translated messages.

Alpha!

This is the first alpha release of 4.0.0. Alpha releases do not have the complete API from 3.x on the nRF builds and are only meant for testing. (Beta release will have the full existing API but still need work.) Please use the latest stable release when first starting with CircuitPython. It is stable.

When you find a bug please check the current known issues and file an issue if something isn't already known.

Installation

To install follow the instructions in our new 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).

Most builds are available as both UF2 and bin files here along with test builds.

New Features

• nrf: Adds nrf52840 USB support. Thanks @hathach, @arturo182, @dhalbert and @jerryneedell.
• Adds translated messages for German (de_DE), French(fr), Spanish (es) and Tagalog (fil). English is available as en_US. Thanks to @turbinenreiter, @arofarn, Pierrick C, @C47D, @eighthree, and @tannewt.
• atmel-samd: Adds support for Grand Central M4 Express, Hallowing M0 Express and Trellis M4.
• Adds displayio to manage displays. Thanks to @tannewt, @jedgarpark, @ladyada and @dhalbert.
• Adds dynamic VM memory management by changing stack size with supervisor.set_next_stack_limit. Thanks to @tannewt and @dhalbert.

Breaking Changes!

None so far.

Thanks

Thank you to all who used, tested, contributed, helped out, and participated on GitHub and/or Discord:
@ladyada, @dhalbert, @tannewt, @kattni, @microbuilder, @arturo182, @tralamazza, @hathach, @glennrub, @siddacious, @deshipu, @sommersoft, @jerryneedell, @brentru, @caternuson, @dfarning, @jepler, @PaulKierstead, @notro, @Jahor, @Makdaam, @mrmcwethy and surely more we have missed. Join us on the Discord chat to collaborate.

Documentation

Documentation is available in readthedocs.io.

Here are all the changes since 3.0.2.

This release is based on MicroPython 1.9.4 @25ae98f. Support upstream MicroPython by purchasing a PyBoard (from Adafruit here).

Troubleshooting

Check out this guide for info on common problems with CircuitPython. If you are still having, then post to the Adafruit Support Forums and join Discord.