Update without timer since read is blocking

scripts/stream_node.py

@@ -21,7 +21,7 @@ import ue9
 
 
 class Labjack(object):
-    def __init__(self, channel, resolution=16, scan_freq=150):
+    def __init__(self, channel, resolution=16, scan_freq=366):
         self.channel_name = "AIN"+str(channel)
         self.d = ue9.UE9()
         self.d.getCalibrationData()
@@ -39,21 +39,24 @@ class Labjack(object):
         # Anonymous topic ?
         self.pub = rospy.Publisher('chatter', Float32, queue_size=10)
 
-        timer_period = 0.01  # in second
-        self.timer = rospy.Timer(rospy.Duration(timer_period), self.timer_callback)
-        rospy.spin()
+        #timer_period = 0.01  # in second
+        #self.timer = rospy.Timer(rospy.Duration(timer_period), self.timer_callback)
+        #rospy.spin()
+
+        while rospy.is_shutdown() is False:
+            self.timer_callback()
 
         self.d.streamStop()
         self.d.close()
 
-    def timer_callback(self, event):
+    def timer_callback(self):
         msg = Float32()
         # Conversion in milli volt for gain 1
-        for data in self.d.streamData():
-            if data is not None:
-                msg.data = sum(data[self.channel_name])/len(data[self.channel_name])
-                rospy.loginfo('Publishing: "{0}"'.format(msg.data))
-                self.pub.publish(msg)
+        data = next(self.d.streamData())
+        if data is not None:
+            msg.data = sum(data[self.channel_name])/len(data[self.channel_name])
+            rospy.loginfo('Publishing: "{0}"'.format(msg.data))
+            self.pub.publish(msg)
 
 
 if __name__ == '__main__':