Better serial console.

sercom.py

#!/usr/bin/env python3

import serial
import sys
import os
import threading
import traceback

if len(sys.argv) not in (2, 3):
    print(f"Usage: {sys.argv[0]} <path> [baud]")
    exit(1)

if len(sys.argv) == 2:
    ser = serial.Serial(sys.argv[1])
else:
    ser = serial.Serial(sys.argv[1], baudrate=sys.argv[2])

print(str(ser))
print("Hit 'Ctrl-A q' to exit.")

def terminate(code=1):
    os.system("stty sane")
    ser.close()
    print()
    os._exit(code)

def read_loop():
    try:
        while True:
            ch = ser.read(1)
            sys.stdout.buffer.write(ch)
            sys.stdout.buffer.flush()
    except:
        traceback.print_exc()
        terminate()

def write_loop():
    try:
        cmd_mode = False
        while True:
            ch = sys.stdin.buffer.read(1)
            if ch == b'\x01':
                if cmd_mode:
                    ser.write(ch)
                    cmd_mode = False
                else:
                    cmd_mode = True
            elif cmd_mode:
                if ch == b'q':
                    terminate(0)
                cmd_mode = False
            else:
                ser.write(ch)
    except:
        traceback.print_exc()
        terminate()

os.system("stty raw -echo")
try:
    read_thread = threading.Thread(target=read_loop)
    write_thread = threading.Thread(target=write_loop)
    read_thread.start()
    write_thread.start()

    read_thread.join()
    write_thread.join()
except:
    traceback.print_exc()
    terminate()