MicroPython cross compiler

This directory contains the MicroPython cross compiler, which runs under any Unix-like system and compiles .py scripts into .mpy files.

Build it as usual:

$ make

The compiler is called mpy-cross. Invoke it as:

$ ./mpy-cross foo.py

This will create a file foo.mpy which can then be copied to a place accessible by the target MicroPython runtime (eg onto a pyboard's filesystem), and then imported like any other Python module using import foo.

Different target runtimes may require a different format of the compiled bytecode, and such options can be passed to the cross compiler. For example, the unix port of MicroPython requires the following:

$ ./mpy-cross -mcache-lookup-bc foo.py

If the Python code contains @native or @viper annotations, then you must specify -march to match the target architecture.

Run ./mpy-cross -h to get a full list of options.

The optimisation level is 0 by default. Optimisation levels are detailed in https://docs.micropython.org/en/latest/library/micropython.html#micropython.opt_level