A serial port bridge monitor written by python3

pyseridge.py

#!/usr/bin/env python3

import queue
import signal
import sys
import threading
from datetime import datetime
from time import time

from serial import Serial


def serial_port_relay(q, port_from, port_to):
    pfn = port_from.name
    while True:
        byte = port_from.read(size=1)
        port_to.write(byte)
        q.put((pfn, time(), byte))


def logger(q):
    c = 0
    p_old = None
    while True:
        p, t, b = q.get()
        if p == p_old:
            print('%02X ' % b[0], end='', flush=True)  # flush=True
        else:
            c += 1
            p_old = p
            print('\n\n[{count}] {port}: {ts}'.format(
                count=c, ts=datetime.fromtimestamp(t), port=p))
            print('%02X ' % b[0], end='', flush=True)


def win32_ctrl_c():
    if sys.platform == 'win32':
        # %ERRORLEVEL% = '-1073741510'
        signal.signal(signal.SIGINT, signal.SIG_DFL)


if __name__ == '__main__':
    win32_ctrl_c()
    try:
        p1 = Serial(sys.argv[1])
        p2 = Serial(sys.argv[2])
        if len(sys.argv) > 3:
            p1.baudrate = p2.baudrate = sys.argv[3]
        q = queue.Queue()
        tp = threading.Thread(target=logger, args=(q, ))
        t1 = threading.Thread(target=serial_port_relay, args=(q, p1, p2))
        t2 = threading.Thread(target=serial_port_relay, args=(q, p2, p1))
        tp.start()
        t1.start()
        t2.start()
    except IndexError:
        print('Usage: {} portA portB [baudrate]'.format(sys.argv[0]))