Mouse2.py

#!/usr/bin/env python

import rospy
import sys
import usb.core
import usb.util
from position_tracking.msg import Mouse_data

md = Mouse_data()
md.x=0.0
md.y=0.0
x=0.0
y=0.0
factor = 0.0000077244
def register_data(event):
        print str(event.current_real)
        md.x=round(x,5)
        md.x=round(x,5)
        md.y=round(y,5)
        x=0.0
        y=0.0
        rospy.loginfo(md)
        publish.publish(md)


if __name__=='__main__':
	print 'in main'
	# decimal vendor and product values
	#dev = usb.core.find(idVendor=10077, idProduct=2982)
	#this id is found by using the finddevices code
	# or, uncomment the next line to search instead by the hexidecimal equivalent
	dev = usb.core.find(idVendor=0x046d, idProduct=0xc084)
	#dev = usb.core.find(idVendor=0x275d, idProduct=0xba6)
	# first endpoint
	interface = 0
	endpoint = dev[0][(0,0)][0]
	# if the OS kernel already claimed the device, which is most likely true
	# thanks to http://stackoverflow.com/questions/8218683/pyusb-cannot-set-configuration
	if dev.is_kernel_driver_active(interface) is True:
	  	# tell the kernel to detach
        	dev.detach_kernel_driver(interface)
	  	# claim the device
        	usb.util.claim_interface(dev, interface)

	#md = Mouse_data()
	#md.x=0.0
	#md.y=0.0
	#x=0.0
	#y=0.0
	#factor = 0.0000077244
	#count=25
	rospy.init_node('mouse_data', anonymous =True)
	publish = rospy.Publisher('mouse_odom', Mouse_data , queue_size = 10)
	rate = rospy.Rate(125)

	while not rospy.is_shutdown():
	        try:
	                data = dev.read(endpoint.bEndpointAddress,endpoint.wMaxPacketSize)
	                if data[5]>=127:      #IF the mouse is moving in the positiv$
	                        y=y+(256-data[4])*factor
	                else:
	                        y=y-data[4]*factor
	                if data[3]>=127:      #IF the mouse is moving in the negativ$
	                        x=x-(256-data[2])*factor
	                else:
	                        x=x+(data[2])*factor
	        except usb.core.USBError as e:
	                data = None
	                if e.args == ('Operation timed out',):
	                        continue
		rospy.Timer(rospy.Duration(0.2),register_data)
#	count-=1
#        if count==0 :
#		md.x=round(x,5)
#		md.y=round(y,5)
#		x=0.0
#		y=0.0
#		rospy.loginfo(md)
#		publish.publish(md)
#		count=25
#	rospy.loginfo(md)
#	publish.publish(md)
		rate.sleep()

# release the device
	usb.util.release_interface(dev, interface)
# reattach the device to the OS kernel
	dev.attach_kernel_driver(interface)
if __name__=='__main__':
        print 'in main'