LED staying on with asyncio (RP2040)

[SandyWalsh]

MPY: soft reboot
MicroPython v1.23.0 on 2024-06-02; Raspberry Pi Pico with RP2040

>>> os.uname()
(sysname='rp2', nodename='rp2', release='1.23.0', version='v1.23.0 on 2024-06-02 (GNU 13.2.0 MinSizeRel)', machine='Raspberry Pi Pico with RP2040')

My program

from machine import Pin
import asyncio

async def blink(led, period_ms, evt):
    try:
        print("START")
        while not evt.is_set():
            print("-ON")
            led.on()
            await asyncio.sleep_ms(5)
            led.off()
            print("-OFF")
            await asyncio.sleep_ms(period_ms)
        print("EXIT")
    except:
        print("ERROR")
        for x in range(5):
            led.on()
            await asyncio.sleep(100)
            led.off()
            await asyncio.sleep(100)

async def main(led):
    event=asyncio.Event()
    print("$ MAIN")
    t=asyncio.create_task(blink(led, 700, event))
    print("$ SLEEPING")
    await asyncio.sleep(3)
    print("$ SETTING FLAG")
    event.set()
    print("$ WAITING")
    await asyncio.wait_for(t, 1000)
    print("$ DONE")

led=Pin(25, Pin.OUT, value=0)
asyncio.run(main(led))

The output looks correct (ends with a "-OFF" message)

>>> asyncio.run(main(led))
$ MAIN
$ SLEEPING
START
-ON
-OFF
-ON
-OFF
-ON
-OFF
-ON
-OFF
-ON
-OFF
$ SETTING FLAG
$ WAITING
EXIT
$ DONE

But the LED is staying on about 50% of the time. If I explicitly do a finally: led.off() it's fine, but that shouldn't be necessary.

Thoughts?

Originally posted by @SandyWalsh in #16016

[peterhinch]

I can't replicate this. The LED always ends up off.

Two comments. The timeout never occurs, but please read this for a discussion on error trapping.

Secondly, I am converting this to a discussion - please don't raise issues in the MP bug tracker unless you have evidence of a MP bug.

[SandyWalsh]

duplicate https://github.com/orgs/micropython/discussions/16024