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.

CircuitPython 3.0.3

This is the a bug fix and minor feature release for the 3.x stable series. There is one fix in this release. Please check out the 3.0.0 release notes for full details on what's new in 3.0.0.

Changes since 3.0.2

• atmel-samd: Fix AudioOut playback on the SAMD21. Thanks to jct4764 on the forum for the bug report, @caternuson and @sommersoft for verifying it and @tannewt for the fix.

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 3.0.2.

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 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 3.0.2

This is the a bug fix and minor feature release for the 3.x stable series. There are a few important fixes and some additions to busio.UART. Please check out the 3.0.0 release notes for full details on what's new in 3.0.0.

Changes since 3.0.1

• Adjust neopixel write timings on the M4: On-board NeoPixel stopped working on M4 boards in 3.0.1. Thanks to @jerryneedell for the fix and testing, and @ash0x1b for the issue.
• Handle USB output buffer >255 characters. Thanks @daguitarguy for the issue, initially noticed in the REPL, and thanks @dhalbert for the fix.
• Allocate PWMOut timer channels correctly. Previously some TCC timer channels were being incorrectly reused in multiple PWMOut objects. Thanks @deshipu for the issue and @dhalbert for the fix.
• When UART timeout of zero is given, make UART.read() return available data. Thanks to @PaulKierstead for the fix.
• Re-initialize default board busses on soft reset (board.SPI, board.I2C, board.UART). Thanks @dhalbert.
• Add UART.in_waiting and UART.reset_input_buffer(), which mirror functionality in PySerial. Thanks @dhalbert, and thanks to @ladyada for the suggestions.

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 3.0.0.

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.

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 3.0.1

This is the first bug fix release for the 3.x stable series. It brings a few important fixes and support for the Hallowing M0 Express. Please check out the 3.0.0 release notes for full details on whats new in 3.0.0.

Changes since 3.0.0

• Speed up import. Thanks @dhalbert for the fix and @daguitarguy for filing the issue.
• Fix neopixel write timings on the M4 for SK6812 on 5V. Thanks to @tannewt for the fix, @Thomasinator for the issue and @jerryneedell for testing.
• Fix UART on SAMDs. Thanks to @jepler for the find and the fix. Thanks to @jerryneedell for testing.
• Add Hallowing M0 Express support. Thanks to @dhalbert and @ladyada.

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 3.0.0.

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.

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.

3.0.0

3.0.0 is the latest major revision of CircuitPython and features new support for the SAMD51 (aka M4) and preliminary support for the nRF52 BLE chipset. It also features better memory utilization so more can be loaded in the same amount of space.

General release

We believe this release is stable and relatively bug free. So, please try this before trying 2.x. If you find issues please file an issue.

Changes since Release Candidate 1

• Update frozen crickit library. Thanks @dhalbert.
• Fix pull setting for DigitalInOut. Thanks @cater, @kattni, @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.

New Features in 3.0.0

• Support for SAMD51 based M4 boards from Adafruit. Thanks @tannewt, @dhalbert, @siddacious and all the M4 testers.
• Preliminary support for nRF52 BLE capable boards. Thanks @glennrub, @tralamazza, @microbuilder, @arturo182, @hathach and @jerryneedell.
• Long-lived heap allocations are better compacted. (Video) Thanks @tannewt and @dhalbert.
• Read the microcontroller's unique id through microcontroller.cpu.uid. Thanks @sommersoft!
• UART can now be created with only one direction. Thanks @dhalbert!
• Files to prevent mac from indexing the drive are created automatically. Thanks @jepler!
• * and *= implemented for array.array. Thanks @jepler!
• Implemented seeking to non-zero locations. Thanks @aykevl and @jepler.
• Detect when USB has been plugged in with supervisor.runtime.serial_connected. Thanks @sommersoft and @dhalbert.
• Change file system label (CIRCUITPY by default) using storage.getmount("/").label.
• Add storage.erase_filesystem() to make erasing the file system easy. Thanks @dhalbert!
• atmel-samd: usb_hid support include Consumer Controls (aka multimedia keys) and Gamepad. Thanks @dhalbert.
• Support atmel-samd real-time clock (RTC) as main time source. Thanks @notro!
• Add audiobusio.I2SOut support and split samples into audioio.RawSample and audioio.WaveFile. Thanks @tannewt
• AudioOut and I2SOut now support pause and resume while playing back a sample. Thanks @tannewt
• samd.clock added to enable low level clock tuning. Thanks @notro
• supervisor.reload() now available to reload the VM. It no longer uses KeyboardInterruptException but rather its own ReloadException. Thanks to @rhooper
• Add board.I2C(), board.SPI() and board.UART() as singleton objects for default buses as defined on the board. Thanks to @matt-land
• Longints are now supported on M0 Express boards (along with M4 boards). Thanks to @notro and @dhalbert
• Add custom board for CircuitPlayground Crickit. Thanks to @dhalbert and @ladyada
• Support for the Pirkey M0. Thanks @dhalbert
• Add rotaryio to support rotary encoders. Thanks to @tannewt and @dhalbert
• Auto-pause PulseIn during high frequency input thanks to @tannewt, @dhalbert and @jerryneedell
• ESP8266 is now auto-built by Travis thanks to @jepler
• Code has been reorganized to ease sharing main code across ports.

Breaking Changes!

• ustruct has been replaced with struct to match CPython.
• ucollections has been replaced with collections to match CPython. Thanks @bildzeitung.
• ubinascii is renamed binascii to match CPython. Thanks @jepler
• The mpy format has changed so make sure and use a 3.0.0 bundle for libraries.
• Non-standard array types inherited from MicroPython are no longer supported in favor of matching CPython. Thanks to @jepler.
• audioio.AudioOut now takes the sample to playback in play rather than in the constructor. (This enables playback through other outputs such as audiobusio.I2SOut.) It also means you only need one AudioOut for multiple samples.
• PDMIn's frequency property has been renamed to sample_rate.
• Trinket M0 and Gemma M0 builds no longer include pin objects for all microcontroller pins. They only include those used by the board. Thanks to @rhooper
• Auto-reload no longer uses KeyboardInterruptException but rather its own ReloadException. Thanks to @rhooper

Thanks

Thank you to all who used, tested, contributed, helped out, and participated on GitHub, sprinted with us at PyCon and/or chatted with us on Discord:
@ladyada, @dhalbert, @tannewt, @kattni, @microbuilder, @arturo182, @jamesadevine, @tralamazza, @hathach, @glennrub, @siddacious, @deshipu, @tdicola, @mrmcwethy, @willingc, @sommersoft, @deanm1278, @jerryneedell, @stewmystre, @boneskull, @Sigafoos, @brentru, @caternuson, @process1183, @Andon-A, @asherlie, adamwolf, dastels, @hukuzatuna, @KurticusMaximus, nis, BravoDelta, aj_nys, @wolf, @vesperk38, @jepler, @notro, CGrover, @larsks, @WestfW, @rhooper, @khawley, @godlygeek, @bildzeitung, @matt-land, @wickedchicken, @margaret, sdw_nj, @ntoll, @SConaway, @dglaude, @nickzoic, MikeBarela, Josh, Les, @cefn, papahabla, hotcarrier, Bill_R, and from PyCon sprints: Dylan W, Anders, David, Dylan H, Adam, John, Chris, Lady Red, Craig, Aaron, John, Boris, Drew and Kathryn and surely more we have missed. Join us on the Discord chat to collaborate.

Documentation

Documentation is available on readthedocs.io.

Here are all the changes since 2.3.1.

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.

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.

3.0.0 Release Candidate 1

3.0.0 is the latest major revision of CircuitPython and features new support for the SAMD51 (aka M4) and preliminary support for the nRF52 BLE chipset. It also features better memory utilization so more can be loaded in the same amount of space.

Release Candidate

We believe this release is stable and relatively bug free. So, please try this before trying 2.x. If you find issues please file an issue. If no major bugs are found, then we'll release this as 3.0.0 stable.

Changes since Release Candidate 0

• Fix M4 RTC. Thanks @mrmcwethy and @notro
• Fix / mounting. Thanks @dhalbert
• Freeze in crickit library. Thanks @dhalbert, @jerryneedell and @papahabla
• Fix one wire. Thanks @dhalbert, @caternuson, @sommersoft, Bill_R, and hotcarrier
• Add D3 and D4 definitions to Itsy Bitsy M4. Thanks @jerryneedell

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.

New Features in 3.0.0

• Support for SAMD51 based M4 boards from Adafruit. Thanks @tannewt, @dhalbert, @siddacious and all the M4 testers.
• Preliminary support for nRF52 BLE capable boards. Thanks @glennrub, @tralamazza, @microbuilder, @arturo182, @hathach and @jerryneedell.
• Long-lived heap allocations are better compacted. (Video) Thanks @tannewt and @dhalbert.
• Read the microcontroller's unique id through microcontroller.cpu.uid. Thanks @sommersoft!
• UART can now be created with only one direction. Thanks @dhalbert!
• Files to prevent mac from indexing the drive are created automatically. Thanks @jepler!
• * and *= implemented for array.array. Thanks @jepler!
• Implemented seeking to non-zero locations. Thanks @aykevl and @jepler.
• Detect when USB has been plugged in with supervisor.runtime.serial_connected. Thanks @sommersoft and @dhalbert.
• Change file system label (CIRCUITPY by default) using storage.getmount("/").label.
• Add storage.erase_filesystem() to make erasing the file system easy. Thanks @dhalbert!
• atmel-samd: usb_hid support include Consumer Controls (aka multimedia keys) and Gamepad. Thanks @dhalbert.
• Support atmel-samd real-time clock (RTC) as main time source. Thanks @notro!
• Add audiobusio.I2SOut support and split samples into audioio.RawSample and audioio.WaveFile. Thanks @tannewt
• AudioOut and I2SOut now support pause and resume while playing back a sample. Thanks @tannewt
• samd.clock added to enable low level clock tuning. Thanks @notro
• supervisor.reload() now available to reload the VM. It no longer uses KeyboardInterruptException but rather its own ReloadException. Thanks to @rhooper
• Add board.I2C(), board.SPI() and board.UART() as singleton objects for default buses as defined on the board. Thanks to @matt-land
• Longints are now supported on M0 Express boards (along with M4 boards). Thanks to @notro and @dhalbert
• Add custom board for CircuitPlayground Crickit. Thanks to @dhalbert and @ladyada
• Support for the Pirkey M0. Thanks @dhalbert
• Add rotaryio to support rotary encoders. Thanks to @tannewt and @dhalbert
• Auto-pause PulseIn during high frequency input thanks to @tannewt, @dhalbert and @jerryneedell
• ESP8266 is now auto-built by Travis thanks to @jepler
• Code has been reorganized to ease sharing main code across ports.

Breaking Changes!

• ustruct has been replaced with struct to match CPython.
• ucollections has been replaced with collections to match CPython. Thanks @bildzeitung.
• ubinascii is renamed binascii to match CPython. Thanks @jepler
• The mpy format has changed so make sure and use a 3.0.0 bundle for libraries.
• Non-standard array types inherited from MicroPython are no longer supported in favor of matching CPython. Thanks to @jepler.
• audioio.AudioOut now takes the sample to playback in play rather than in the constructor. (This enables playback through other outputs such as audiobusio.I2SOut.) It also means you only need one AudioOut for multiple samples.
• PDMIn's frequency property has been renamed to sample_rate.
• Trinket M0 and Gemma M0 builds no longer include pin objects for all microcontroller pins. They only include those used by the board. Thanks to @rhooper
• Auto-reload no longer uses KeyboardInterruptException but rather its own ReloadException. Thanks to @rhooper

Thanks

Thank you to all who used, tested, contributed, helped out, and participated on GitHub, sprinted with us at PyCon and/or chatted with us on Discord:
@ladyada, @dhalbert, @tannewt, @kattni, @microbuilder, @arturo182, @jamesadevine, @tralamazza, @hathach, @glennrub, @siddacious, @deshipu, @tdicola, @mrmcwethy, @willingc, @sommersoft, @deanm1278, @jerryneedell, @stewmystre, @boneskull, @Sigafoos, @brentru, @caternuson, @process1183, @Andon-A, @asherlie, adamwolf, dastels, @hukuzatuna, @KurticusMaximus, nis, BravoDelta, aj_nys, @wolf, @vesperk38, @jepler, @notro, CGrover, @larsks, @WestfW, @rhooper, @khawley, @godlygeek, @bildzeitung, @matt-land, @wickedchicken, @margaret, sdw_nj, @ntoll, @SConaway, @dglaude, @nickzoic, MikeBarela, Josh, Les, @cefn, papahabla, hotcarrier, Bill_R, and from PyCon sprints: Dylan W, Anders, David, Dylan H, Adam, John, Chris, Lady Red, Craig, Aaron, John, Boris, Drew and Kathryn and surely more we have missed. Join us on the Discord chat to collaborate.

Documentation

Documentation is available on readthedocs.io.

Here are all the changes since 2.3.1.

This release is based on MicroPython 1.9.3. 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.