antscan

#!/usr/bin/env python
#
# Scan for ANT+ sensors and print out their types and uids

import sys, os
from antlistener import AntStick
from ant.core.message import ChannelBroadcastDataMessage, ChannelRequestMessage, ChannelIDMessage
from ant.core.constants import MESSAGE_CHANNEL_ID

def main(serial_device):
	ant_stick = AntStick(serial_device)
	ant_stick.open_channel('0')
	device_type_uid = [None]
	for timestamp, msg in ant_stick.receive_messages():
		if isinstance(msg, ChannelBroadcastDataMessage):
			cnum = msg.getChannelNumber()
			if device_type_uid[cnum] is None:
				# We don't know what this channel has paired with, ask the stick.
				msg = ChannelRequestMessage(number=cnum, message_id=MESSAGE_CHANNEL_ID)
				ant_stick.send_msg(msg, False)
		elif isinstance(msg, ChannelIDMessage):
			# Response to a message channel id request
			devtype = msg.getDeviceType() 
			uid = msg.getDeviceNumber()
			if devtype == 0 or uid == 0:
				# Nope, the stick hasn't yet worked out what device is connected.
				continue
			cnum = msg.getChannelNumber()
			if device_type_uid[cnum] is None:
				# The first such response on this channel
				print "Paired with device TYPE=%d UID=%d on channel %d" % (devtype, uid, cnum)
				device_type_uid[cnum] = "%d.%d" % (devtype, uid)
				# As this channel is now paired with a device, we need to open another to scan for more.
				ant_stick.open_channel('0')
				device_type_uid.append(None)

if __name__ == '__main__':
	args = sys.argv[1:]
	if len(args) != 1:
		print >> sys.stderr, "Usage: antscan <ANT_STICK_TTY_DEVICE>"
		sys.exit(-1)
	tty = args[0]
	if not os.path.exists(tty):
		print >> sys.stderr, "First argument must be the name of a serial device connected to an ANT+ USB stick, e.g. /dev/ttyUSB0"
		sys.exit(-1)
	main(tty)