Python操作串口的方法

import serial 
import sys 
try: 
  ser = serial.Serial('/dev/ttyUSB0', 9600) 
except Exception, e: 
  print 'open serial failed.' 
  exit(1) 
print 'A Serial Echo Is Running...' 
while True: 
  # echo 
  s = ser.read() 
  ser.write(s) 
  # write to stdout and flush it 
  sys.stdout.write(s) 
  sys.stdout.flush()