CircuitPython 5.0.0 Release Candidate 0! — @adafruit @circuitpython

This is a 5.0.0 Release Candidate — please test
This is release 5.0.0-rc.0 (Release candidate 0). If this release does not have show-stopper issues, it will be re-released as 5.0.0, the first 5.x.x stable release.
If you find a bug please check the current known issues and file an issue if something isn’t already known.
5.0.0
5.0.0 is the latest major revision of CircuitPython. It features many improvements and enhancements to displayio, including grayscale OLED and e-paper displays, extensive additions and improvements to BLE support, support for the STM32F4, iMX RT10xx and Sony Spresense microcontroller families, and PWM audio support.
Download from circuitpython.org
Downloads are available from circuitpython.org! The site makes it easy to select the correct file and language for your board. The downloads page is here.
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).
New Features, Updates, and Fixes since 5.0.0 Beta 5
General
- Speed up heap allocation by tracking first free chunk for multiple block sizes. Thanks @tannewt.
- Fix crash after empty REPL session. Thanks @tannewt.
- Fix MacOS crash when Mac wakes up with an ejected CIRCUITPY. Thanks @tannewt.
- Added draft implementation of
eveL, the Gameduino low-level bindings. Thanks @jamesbowman. - Allow
storage.remount()to work even if MSC is disabled. Thanks @bmeisels. time.monotonic_ns()is now accurate to microseconds.time.sleep()now rounds to the nearest millisecond. Thanks @dhalbert.- Include filename in “No such file/directory” error messages. Thanks @dhalbert.
- Fix
os.stat()integer overflow on non-longint builds. Thanks @dhalbert. - Implement
to_bytes(..., signed=True). Thanks @dhalbert. - Support echoing of Unicode characters in REPL. Thanks @DavePutz.
- Add RTS/CTS and RS485 capabilities to
busio.UART. Thanks @mubes.displayio - Update rotation so 0 is the default, making
OnDiskBitmapmuch faster. Thanks @ladyada. - Allow tuple or list for
displayio.Palettecolor. Thanks @dhalbert. - Fix
OnDiskBitmapdocumentation. Thanks @makermelissa.nRF and BLE
- Add cached buffer on heap for nRF
neopixel_write. Thanks @rhooper and @dhalbert. - Add nRF SPIM3 support, allowing 32MHz SPI. Thanks @dhalbert.
- Fix using too-small SPI transactions on nRF. Thanks @dhalbert.
- Correct I2C frequency setting on nRF. Thanks @dhalbert.
- Enable
_bleiosingletonAdapterwhen_bleiois imported. Thanks @dhalbert. - Disable experimental BLE file editing service for now. Thanks @tannewt.
- Improve BLE error messages. Thanks @tannewt.
STM
- Add core temperature and voltage for STM32. Thanks @hierophect.
i.MX
- Fix SPI clock speed on iMX. Thanks @mubes.
- Fix i.MX UART initialization. Thanks @mubes.
- Enable
displayioformimxrt10xxboards. Thanks @arturo182. - Add directly loadable image support for i.MX. Thanks @mubes.
Other board-specific fixes
- Fix Arduino MKR Zero USB VID. Thanks @fgallaire.
- Add additional pin definitions for OHS2020 board. Thanks @pdp7.
Build infrastructure
- Add support for W25Q80DV external flash chip. Thanks @lgnashold.
- Allow CIRCUITPY drive name to be set in
mpconfigboard.h. Thanks @mubes. - Fix a build alignment warning. Thanks @mubes.
- Fix build checks for proper flash granularity for flash erases. Thanks @dhalbert.
New Boards
Find downloads for all boards, including these, at https://ift.tt/2Tx6WJB.
New since 5.0.0-beta.5
- SparkFun SAMD51 Thing Plus. Thanks @jepler.
- Feather M7 1011. Thanks @arturo182.
- Arduino Nano 33 IoT. Thanks @fgallaire.
- PyCubed. Thanks @maholli.
- Espruino Wifi. Thanks @hierophect.
- Espruino Pico. Thanks @hierophect.
- CircuitBrains Basic. Thanks @neubauek.
- CircuitBrains Deluxe. Thanks @neubauek.
Breaking Changes and Deprecations from 4.x
- 5.0.0 improves our internal filesystem definitions and may overwrite your existing files so make sure to back them up before updating!
- The
bleiomodule has been renamed to_bleioto indicate that it is meant to be used only for writing BLE libraries, and that its API may change between CircuitPython minor versions. There are many incompatible changes in_bleiosince 4.0.0. Please use the latestadafruit_blelibrary for end-user BLE programming. - The
displayiorefresh API has been revamped to be simpler.wait_for_frameandrefresh_soonhave been removed. In both 4.x and 5.x, auto refresh will automatically refresh the display so they can be removed. The newauto_refreshproperty andrefresh()function can be used to control when the screen refreshes and at a specific rate. - Moved
audioio.Mixertoaudiomixer.Mixer, which is only available on M4s. Movedaudioio.RawSample, andaudioio.WaveFileto the new moduleaudiocore. However, for backwards compatibility, they are still available inaudioio. They will be removed fromaudioioin 6.0.0. Thanks @jepler. - Added
I2C.writeto_then_readfrom(). Deprecatestop=arg which will be removed in 6.x. UseI2C.writeto_then_readfrom()instead. - Removed
refrom CircuitPlayground Express Display build. - Removed
gamepadfrom CircuitPlayground Express Crickit build.
Known Issues
displayiooperations that read from an SD card (e.g.,OnDiskBitmap) will interfere with other SD card operations and can cause lockup. To work around this problem, do not read or write files on the SD while the display is updating, and vice versa.- See https://ift.tt/2j1euBi for other issues.@
Thanks
Thank you to all who used, tested, contributed, helped out, and participated on GitHub and/or Discord, including @arturo182, @bmeisels, @DavePutz, @dhalbert, @fgallaire, @hierophect, @jamesbowman, @jepler, @ladyada, @lgnashold, @maholli, @makermelissa, @mubes, @neubauek, @pdp7, @rhooper, @tannewt, @ATMakersBill, @AndrewTribble, @Anne B, @Antonio, @CGrover, @CarlFK, @Curt Olson, @Dar, @DaveP, @DavidGlaude, @DudeImOnly6, @Duewester, @KingerNorth, @SouthernDragon, @TG-Techie, @ThomasAtBBTF, @adafruit, @anecdata, @brentru, @cater, @charlesburnaford, @codeNSolder, @deshipu, @dherrada, @diegoMini+, @ednl, @foamyguy, @geekguy, @graham, @hexthat, @jasonp, @jerryn, @kattni, @kjw, @madbodger, @marius_450, @mscosti, @ntoll, @siddacious, @sommersoft, @stargirl, @timvictor, @v923z 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 5.0.0-beta.5.
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 issues, then post to the Adafruit Support Forums and join Discord.