Hi. I am new to GPS and have a basic question, so please bear with me. My purpose is to obtain speed and position data as and when I want it (for this I understand I need to use $PSRF103 to query for GGL/VTG). My question is, apart from this, what are the basics I have to take care of before even trying to get the data? Am I supposed to constantly monitor the number of satellites? The quality of the fix? Other things? If I have two states such as “OK to query data” and “Not OK to query data” (from the GPS), how to I determine that it is OK? Sorry if this is a bit confused and thanks for your answers.