#!/usr/bin/env python
"""Program which detects USB serial ports.
This program will search for a USB serial port using a search criteria.
In its simplest form, you can use the -l (--list) option to list all of
the detected serial ports.
You can also add the following filters:
--vid 2341 Will only match devices with a Vendor ID of 2341.
--pid 0001 Will only match devices with a Product ID of 0001
--vendor Micro Will only match devices whose vendor name starts with Micro
--seral 00123 Will only match devices whose serial number stats with 00123
If you use -l or --list then detailed information about all of the matches
will be printed. If you don't use -l (or --list) then only the name of
the device will be printed (i.e. /dev/ttyACM0). This is useful in scripts
where you want to pass the name of the serial port into a utiity to open.
"""
from __future__ import print_function
import pyudev
import sys
import argparse
def is_usb_serial(device, vid=None, pid=None, vendor=None, serial=None, *args,
**kwargs):
"""Checks device to see if its a USB Serial device.
The caller already filters on the subsystem being 'tty'.
If serial_num or vendor is provided, then it will further check to
see if the serial number and vendor of the device also matches.
"""
if 'ID_VENDOR' not in device.properties:
return False
if vid is not None:
if device.properties['ID_VENDOR_ID'] != vid:
return False
if pid is not None:
if device.properties['ID_MODEL_ID'] != pid:
return False
if vendor is not None:
if 'ID_VENDOR' not in device.properties:
return False
if not device.properties['ID_VENDOR'].startswith(vendor):
return False
if serial is not None:
if 'ID_SERIAL_SHORT' not in device.properties:
return False
if not device.properties['ID_SERIAL_SHORT'].startswith(serial):
return False
return True
def extra_info(device):
extra_items = []
if 'ID_VENDOR' in device.properties:
extra_items.append("vendor '%s'" % device.properties['ID_VENDOR'])
if 'ID_SERIAL_SHORT' in device.properties:
extra_items.append("serial '%s'" % device.properties['ID_SERIAL_SHORT'])
if extra_items:
return ' with ' + ' '.join(extra_items)
return ''
def list_devices(vid=None, pid=None, vendor=None, serial=None, *args,
**kwargs):
devs = []
context = pyudev.Context()
for device in context.list_devices(subsystem='tty'):
if is_usb_serial(device, vid=vid, pid=pid, vendor=vendor,
serial=serial):
devs.append([device.properties['ID_VENDOR_ID'], device.properties['ID_MODEL_ID'],
extra_info(device), device.device_node])
return devs
def main():
"""The main program."""
parser = argparse.ArgumentParser(
prog="find-port.py",
usage="%(prog)s [options] [command]",
description="Find the /dev/tty port for a USB Serial devices",
)
parser.add_argument(
"-l", "--list",
dest="list",
action="store_true",
help="List USB Serial devices currently connected"
)
parser.add_argument(
"-s", "--serial",
dest="serial",
help="Only show devices with the indicated serial number",
default=None,
)
parser.add_argument(
"-n", "--vendor",
dest="vendor",
help="Only show devices with the indicated vendor name",
default=None
)
parser.add_argument(
"--pid",
dest="pid",
action="store",
help="Only show device with indicated PID",
default=None
)
parser.add_argument(
"-v", "--verbose",
dest="verbose",
action="store_true",
help="Turn on verbose messages",
default=False
)
parser.add_argument(
"--vid",
dest="vid",
action="store",
help="Only show device with indicated VID",
default=None
)
args = parser.parse_args(sys.argv[1:])
if args.verbose:
print('pyudev version = %s' % pyudev.__version__)
if args.list:
'''Print all USB Serial devices'''
devices = list_devices(**vars(args))
for device in devices:
print('USB Serial Device {}:{}{} found @{}'.format(*device))
if len(devices) == 0:
print('No USB Serial devices detected.')
return
context = pyudev.Context()
for device in context.list_devices(subsystem='tty'):
if is_usb_serial(device, **vars(args)):
print(device.device_node)
return
sys.exit(1)
if __name__ == "__main__":
main()
