The 2.3.0 CircuitPython release fixes a longstanding issue of
CIRCUITPY sometimes being erased when applying power or when batteries run down. It also adds the CircuitPlayground and HID libraries as frozen libraries on the Circuit Playground Express build. And finally, if
CIRCUITPY becomes partially corrupted, you can now use
storage.clear_filesystem() to erase and reformat it, and reset the board.
Power-on CIRCUITPY corruption fix
CircuitPython writes version information to
boot_out.txt when it starts from a hard reset or power on. It also writes whatever
settings.py, etc.) prints to
boot_out.txt. If power failed while
boot_out.txt was being written,
CIRCUITPY could become severely corrupted. When power returned, CircuitPython would erase and reformat
CIRCUITPY to fix the corruption. Several things were done to ameliorate this problem:
- Do not rewrite
boot_out.txtif the version information in it will not change and there is no
- If the version information has changed, or there is a
boot.pyfile, wait 1.5 seconds to ensure power is stable before starting to write
- Raise the “brownout” voltage below which CircuitPython refuses to run from 1.7V to 2.8V. This ensures all chips on the board have proper voltage to run.
Additional frozen libraries added to CircuitPython image for Circuit Playground Express
The CircuitPlayground (aka
cpx) library and the HID librariy have been added as frozen libraries to the Circuit Playground Express firmware image. The CircuitPlayground library provides easy access to the built-in sensors and peripherals on the Circuit Playground Express (CPX) board. Using the frozen versions of these libraries can save RAM and allow you to run larger programs. Remove the versions in the
lib/ directory if you want to use the frozen versions. (Or change
sys.path to put
CIRCUITPY becomes partially corrupted, but not badly enough so that it is automatically reformatted. You can now use
erase.filesystem() to reformat easily and quickly, without having to use a special erase
.uf2 file and then reload CircuitPython. In the REPL, just do:
import storage storage.erase_filesystem()
This will erase and reformat
CIRCUITPY, and reset the board.
_stage module now uses 16-bit coordinates to support larger screens. Thanks @deshipu!
The esp8266 build now uses the latest version of the SDK toolchain. Thanks @jepler!
Thanks to @dhalbert, @tannewt, @kattni, @jepler, @deshipu, @ladyada, and @croadfeldt (who helped greatly with testing the power fixes) for help with this release! Join us on the Discord chat to collaborate.
Documentation is available in readthedocs.io.
Here are all the changes since 2.2.4.
mpy-cross executables in this release work fine with 2.3.0.