uasyncio

uasyncio is an asynchronous I/O framework designed for MicroPython and other Python environments with limited resources. It provides an event loop, coroutines, tasks, and future objects, enabling non‑blocking programming on microcontrollers that lack a full operating system. The library is inspired by Python's asyncio module but has been carefully trimmed down to fit within a small memory footprint, making it suitable for devices such as ESP32, STM32, and RP2040.

Programming with uasyncio involves defining async functions and using await on I/O primitives such as sockets, timers, or hardware peripherals. Tasks are scheduled on the event loop, which multiplexes execution across multiple coroutines. Unlike traditional blocking code, this approach allows a single thread to handle many concurrent operations such as network communication, sensor polling, and user interactions without busy waiting.

Key features of uasyncio include timers, file I/O, network sockets, and custom awaitable objects. It also supports cooperative multitasking through coros, letting developers split long operations into discrete steps. The API mirrors that of standard asyncio in many respects, easing the transition for developers familiar with Python’s async/await syntax.

Typical use cases involve creating lightweight web servers, MQTT clients, or home‑automation controllers where low latency and deterministic timing are essential. Example snippets show how to start a web server that serves static content, how to read sensor data via asynchronous callbacks, and how to coordinate multiple tasks using gather or ensure_future.

Overall, uasyncio extends the power of asynchronous programming to resource‑constrained devices, allowing developers to write cleaner, more maintainable code while keeping memory usage low.