![]() Notice the space inserted between degrees and minutes, and no comma before hemisphere designation. The simplest thing you can do to get Google Earth to recognize and properly display the coordinate would be to enter the following: Unfortunately, if you simply try to put 3051.8007,N,10035.9989,W, into Google Earth, it will not recognize it. So, always take the number starting two to the left of the decimal, and those following all the way to the comma, and that is your minutes. What is always the case is that the first two numerals to the left of the decimal place, and the numbers to the right of the decimal represent the minutes. Hence you have to be careful parsing this data. Your Longitude is: 100 degrees 35.9989 minutes, in the Western Hemisphere.ĭegrees could be a one, two or three digit number. Similarly, the next number, 10035.9989,W, is Longitude. Your Latitude is: 30 degrees, 51.007 minutes, in the Northern Hemisphere. 3051.8007,N should be interpreted as follows: Now, for the good stuff, the next number and following letter gives you your lattitude. An ‘A’ indicates you are getting a signal and things are working properly. The next letter just lets you know if your signal is Active (A) or Void (V). Since converting from UTC to your local time is simply a matter of knowing what time zone you are in, you can see that one thing you get from a GPS is a very accurate clock. It works like this, 194530.000 would be 19:45 and 30.0 seconds in UTC. The next number, represents the Coordinated Universal Time (UTC). The $GPRMC is simply telling what sentence type is on the line. If your GPS has a fix, then your GPS sentences should look something like this: If you can not turn the other sentences off, then just ignore them, and focus on the two you care about, $GPRMC, $GPGGA. ![]() If your GPS unit has options to turn the other sentences off, then turn them off to simplify the data getting thrown at you. To make this whole thing a manageable problem, the first thing we must realize is that the data that we want will be in the $GPRMC sentence and the $GPGGA sentence. So, $GPGSA is a certain type of NMEA sentence, and $GPRMC is a different type of NMEA sentence. ![]() There are different NMEA sentence type, and the type is indicated by the first characters before the comma. Each line above is referred to as a NMEA sentence. So, how do we make sense of all this? The first thing is to learn some of the lingo. When it does have a fix, there will be all types of numbers between the commas in the lines above. This is what the data looks like when your GPS does not have a fix. When you connect a GPS board up, and look at the data coming off of it, you are likely to see something like this: In this lesson we will look at what the data coming off the GPS means, and how you can work with it, and get it to display properly in programs like Google Earth. It is as if no one is speaking the same language. It can become a challenge to take the output from a GPS unit, like the Adafruit Ultimate GPS breakout board, and get that data to play nicely with mapping programs like Google earth. GPS units spit out data in a dizzying array of formats.
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