1 files changed, 88 insertions, 0 deletions
diff --git a/gpspoller.py b/gpspoller.py
new file mode 100644
index 0000000..6f7c19c
--- /dev/null
+++ b/gpspoller.py
@@ -0,0 +1,88 @@
+#!/usr/bin/python
+
+# Copyright (C) 2007 by Jaroslaw Zachwieja
+# Modified (C) 2012 by Tim Redfern
+# Published under the terms of GNU General Public License v2 or later.
+# License text available at http://www.gnu.org/licenses/licenses.html#GPL
+
+import serial,string,threading,time,sys,random
+
+class GpsPoller(threading.Thread):
+	
+	latitude = 0
+	longitude = 0
+	changed = False
+	
+	def __init__(self,port,test=False):
+		self.test=test
+		self.port=port
+		self.gps = serial.Serial(port, 9600, timeout=1)
+		threading.Thread.__init__(self)
+		
+	def check(self):
+		if self.changed:
+			self.changed=False
+			return (self.latitude,self.longitude)
+		else:
+			return False
+
+	def run(self):
+		if self.test:
+			print "GpsPoller: serving random data"
+		else:	
+			print "GpsPoller: serving data from",self.port
+		try:
+			while True:
+				if self.test:
+					self.latitude=random.random()*90
+					self.longitude=random.random()*90
+					self.changed=True
+					time.sleep(0.5)
+				else:
+					line = self.gps.read(1)
+					line = line+self.gps.readline()
+					datablock = line.split(',') 
+
+					if line[0:6] == '$GPRMC':
+						latitude_in = string.atof(datablock[3])
+						longitude_in = string.atof(datablock[5])
+						altitude = string.atof(datablock[8])
+						speed_in = string.atof(datablock[7])
+						heading = string.atof(datablock[8])
+
+						if datablock[4] == 'S':
+							 latitude_in = -latitude_in
+						if datablock[6] == 'W':
+							 longitude_in = -longitude_in
+
+						latitude_degrees = int(latitude_in/100)
+						latitude_minutes = latitude_in - latitude_degrees*100
+
+						longitude_degrees = int(longitude_in/100)
+						longitude_minutes = longitude_in - longitude_degrees*100
+
+						latitude = latitude_degrees + (latitude_minutes/60)
+						longitude = longitude_degrees + (longitude_minutes/60)
+						
+						if latitude!=self.latitude or longitude!=self.longitude:
+							self.latitude=latitude
+							self.longitude=longitude
+							self.changed=True
+			
+			
+		except StopIteration:
+			pass
+
+	def __del__():
+		self.gps.close()
+
+if __name__ == '__main__':
+	
+	gpsp = GpsPoller(sys.argv[1])
+	gpsp.start()
+	while 1:
+		# In the main thread, every 5 seconds print the current value
+		time.sleep(0.1)
+		check=gpsp.check()
+		if check!=False:
+			print "changed:",check[0],check[1]