using serial port in python3 asyncio

Question

i\'m trying and, so far, failing to use python asyncio to access a serial port.

i\'d really appreciate any tips on using the new python async framework on a simple fd.

Answer 1

It's other way using FD

import asyncio
import serial

s = serial.Serial('/dev/pts/13', 9600)


def test_serial():
    '''
    read a line and print.
    '''
    text = ""
    msg = s.read().decode()
    while (msg != '\n'):
        text += msg
        msg = s.read().decode()
    print(text)
    loop.call_soon(s.write, "ok\n".encode())

loop = asyncio.get_event_loop()
loop.add_reader(s, test_serial)
try:
    loop.run_forever()
except KeyboardInterrupt:
    pass
finally:
    loop.close()

Answer 2

Consider using aioserial.

Here's an example:

import aioserial
import asyncio


async def read_and_print(aioserial_instance: aioserial.AioSerial):
    while True:
        print((await aioserial_instance.read_async()).decode(errors='ignore'), end='', flush=True)


aioserial_com1: aioserial.AioSerial = aioserial.AioSerial(port='COM1')

asyncio.run(read_and_print(aioserial_com1))

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To the moderator,

The answer is just similar to this one but not duplicated.