- micropython is designed to run on a machine with 192 kilobytes of RAM and perhaps a megabyte of FLASH. The controller can execute read-only code directly from FLASH. There is no dynamic linker in this environment. (It also has a UNIX port). - However it does include a full Python parser and REPL, so the board can be programmed without a separate computer as opposed to, say, having to upload bytecode compiled on a regular computer. - It's definitely going to be a subset of Python. For example, func.__name__ is not supported - to make it more micro? - They have a C API. It is much different than the CPython C API. - It mas more than one code emitter. A certain decorator causes a function to be compiled to ARM Thumb code instead of bytecode. - It even has an inline assembler than translates Python-syntax ARM assembly (to re-use the same parser) into machine code.
Most information from https://www.kickstarter.com/projects/214379695/micro-python-python-for-micro... and http://micropython.org/