Non-blocking read from serial

[PicoUser]

I need a program that listens to serial input from a PC over USB. This listing shouldn't block the continous reading of other sensors because this data is send back over serial to the PC. At the moment, the only way I found to listen to the serial bus is with sys.stdin.readline(), but this is a blocking function.

Is there a way to check if data is available in the serial read bus? Or is it possible to define like a callback functions that runs when data is available? I'm quite new to python so any help is appreciated

Example code

Code: Select all

from machine import Pin
import sys
led = Pin(25, Pin.OUT) #LED pin

while True:
    data = sys.stdin.readline(1) #<-- this line is blocking. It shouldn't

    if data == "N":
        led.on()
    elif data == "F":
        led.off()
        
    print("Working") #represents other code that should continue to run.
    sleep(0.2)

[Roberthh]

See this post for using poll(): viewtopic.php?f=21&t=12162&p=66276&hili ... ing#p66276