pyserial enumerate ports

Question

I need list or enumerate of existing serial ports, Till now I was using this method enumerate_serial_ports(), but its not working with windows 7. Do you know some alternative how can I find out available serial ports under windows 7?

def enumerate_serial_ports():
  """ Uses the Win32 registry to return an 
      iterator of serial (COM) ports 
      existing on this computer.
  """
  path = 'HARDWARE\\DEVICEMAP\\SERIALCOMM'
  try:
      key = winreg.OpenKey(winreg.HKEY_LOCAL_MACHINE, path)
  except WindowsError:
      raise IterationError

  for i in itertools.count():
      try:
          val = winreg.EnumValue(key, i)
          yield str(val[1])
      except EnvironmentError:
          break

I get IterationError

Answer 1

There's now a list_ports module built in to pyserial.

In [26]: from serial.tools import list_ports
In [27]: list_ports.comports()
Out[27]: 
[('/dev/ttyS3', 'ttyS3', 'n/a'),
 ('/dev/ttyS2', 'ttyS2', 'n/a'),
 ('/dev/ttyS1', 'ttyS1', 'n/a'),
 ('/dev/ttyS0', 'ttyS0', 'n/a'),
 ('/dev/ttyUSB0',
  'Linux Foundation 1.1 root hub ',
  'USB VID:PID=0403:6001 SNR=A1017L9P')]

The module can also be executed directly:

$ python -m serial.tools.list_ports
/dev/ttyS0          
/dev/ttyS1          
/dev/ttyS2          
/dev/ttyS3          
/dev/ttyUSB0        
5 ports found

Answer 2

You're raising an IterationError, but that exception doesn't actually exist. Maybe you should try raising EnvironmentError for that condition as well.

The pySerial docs include some sample code for finding serial ports. Check them out: http://pyserial.sourceforge.net/examples.html#finding-serial-ports