CPython supports asynchronous programming via the asyncio library. MicroPython provides uasyncio which is a subset of this, optimised for small code size and high performance on bare metal targets. This repository provides documentation, tutorial material and code to aid in its effective use.

Damien has completely rewritten uasyncio which was released as V3.0. See PR5332. This is now incorporated in release build V1.13 and subsequent daily builds.

Resources for V3 may be found in the v3 directory. These include a guide to porting applications from V2, an updated tutorial, synchronisation primitives and various applications and demos.

V2 should now be regarded as obsolete for almost all applications with the possible exception mentioned below.

The official version 2 is entirely superseded by V3, which improves on it in every respect.

I produced a modified fast_io variant of V2 which is in use for some specialist purposes. It enables I/O to be scheduled at high priority. Currently this schedules I/O significantly faster than V3; the maintainers plan to improve uasyncio I/O scheduling. When this is complete I intend to delete all V2 material.

All V2 resources are in the V2 subdirectory: see this README.