python-asyncio-pyserial-reader.py

# example reading two serial devices using pyserial, asyncio and coroutines

import serial_asyncio
import asyncio

@asyncio.coroutine
def serial_read(device, **kwargs):
    reader, writer = yield from serial_asyncio.open_serial_connection(url=device, **kwargs)
    while True:
        line = yield from reader.readline()
        print(line.decode('ascii').strip())

loop = asyncio.get_event_loop()
tasks = [
    serial_read('/dev/ttyACM0', baudrate=57600),
    serial_read('/dev/ttyUSB0', baudrate=9600, bytesize=7),
]
asyncio.gather(*tasks)
loop.run_forever()
loop.close()