@peterp Note that the 'event.py' which defines a semaphore for asyncio does not load on the latest version, as it depends (for ThreadSafeFlag) on being able to extend uio.IOBase. This base class is not used in the pycom micropython uio port apparently... This is an issue to use asyncio on pycom ports as ThreadSafeFlag is the only way to do a semaphore from an ISR or other _thread task... any ideas?

@martijnthe I have to check that again. As far I recalled, I tested the wrap-around situations.