uflash 1.0.0b3

A module and utility to flash Python onto the BBC micro:bit.

uFlash

THIS MODULE ONLY WORKS WITH PYTHON 2.7 or 3.3+.

A utility for flashing the BBC micro:bit with Python scripts and the MicroPython runtime. You pronounce the name of this utility “micro-flash”. ;-)

It provides two services:

1. A library of functions to programatically create a hex file and flash it onto a BBC micro:bit.

2. A command line utility called uflash that will flash Python scripts onto a BBC micro:bit.

Several essential operations are implemented:

• Encode Python into the hex format.

• Embed the resulting hexified Python into the MicroPython runtime hex.

• Extract an encoded Python script from a MicroPython hex file.

• Discover the connected micro:bit.

• Copy the resulting hex onto the micro:bit, thus flashing the device.

Installation

To install simply type:

$ pip install uflash

…and the package will download from PyPI. If you wish to upgrade to the latest version, use the following command:

$ pip install --no-cache --upgrade uflash

Command Usage

To read help simply type:

$ uflash help

If you type the command on its own then uflash will attempt to find a connected BBC micro:bit and flash an unmodified version of the MicroPython runtime onto it:

$ uflash
Flashing Python to: /media/ntoll/MICROBIT/micropython.hex

To flash a version of the MicroPython runtime with a specified script embedded within it (so that script is run when the BBC micro:bit boots up) then pass the path to the Python script in as the first argument to the command:

$ uflash my_script.py
Flashing Python to: /media/ntoll/MICROBIT/micropython.hex

At this point uflash will try to automatically detect the path to the device. However, if you have several devices plugged in and/or know what the path on the filesystem to the BBC micro:bit already is, you can specify this as a second argument to the command:

$ uflash myscript.py /media/ntoll/MICROBIT
Flashing Python to: /media/ntoll/MICROBIT/micropython.hex

To extract a Python script from a hex file use the “-e” flag like this:

$ uflash -e something.hex myscript.py

This will save the Python script recovered from “something.hex” into the file “myscript.py”. If you don’t supply a target the recovered script will emit to stdout.

Development

The source code is hosted in GitHub. Please feel free to fork the repository. Assuming you have Git installed you can download the code from the canonical repository with the following command:

$ git clone https://github.com/ntoll/uflash.git

Ensure you have the correct dependencies for development installed by creating a virtualenv and running:

$ pip install -r requirements.txt

To locally install your development version of the module into a virtualenv, run the following command:

$ python setup.py develop

There is a Makefile that helps with most of the common workflows associated with development. Typing “make” on its own will list the options thus:

$make

There is no default Makefile target right now. Try:

make clean - reset the project and remove auto-generated assets.
make pyflakes - run the PyFlakes code checker.
make pep8 - run the PEP8 style checker.
make test - run the test suite.
make coverage - view a report on test coverage.
make check - run all the checkers and tests.
make package - create a deployable package for the project.
make publish - publish the project to PyPI.
make docs - run sphinx to create project documentation.

Release History

1.0.0.beta.1

• Works with Python 2.7 (thanks to @Funkyhat).

• Updated to the latest build of MicroPython for the BBC micro:bit.

• Minor refactoring and updates to the test suite due to MicroPython updates.

0.9.17

• Minor code refactor.

• Documentation update.

0.9.14

• Feature complete.

• Comprehensive test suite - 100% coverage.

• Tested on Linux and Windows.

• Documentation.

• Access via the “uflash” command.

0.0.1

• Initial release. Basic functionality.