# coding=utf-8

import serial
import serial.tools.list_ports

def list_com():
	print("----- useful serial port list ------------------------")
	plist = list(serial.tools.list_ports.comports())
	if len(plist) <= 0:
		print("No useful port!")
	else:
		for plist_i in plist:
			serialFd = serial.Serial(plist_i[0], 9600, timeout=1)
			print("- Port : %s"% serialFd.name)
			serialFd.close()
	print("")