GPS program

Hi guys, can anyone tell me which GPS program is giving out an accurate data?
The data that I meant is Latitude, Longitude at least.

From the EM406 gps tester that I've downloaded, the data does not seem to be clear.
Does gs means ground speed? And what does groundspeed do and how does gps measures it?
And the altitude in metres does not seem to be clear. I am at level 7 and it's showing 100 over metres.
And how do I convert a Latitude of 14220578 to a standard form of displaying it in terms of degrees etc?

And the photo below is the program from EM406 GPS, why is there a need to divide the altitude and gs?

I am using the EM406 gps by the way. An accurate GPS is needed.. thanks in advance.

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  • help!
  • The divide by 100 on the parameters is because of memory issues on the processor.

    It takes alot more time and memory for a processor to work with a floating point (decimal) numbers than with integers.

    To get around this, things like altitude (in meters) is multiplied by 100 so that the processor can work with greater precision (centimeters) without having to resort to floating point math.

    So just before the variable gets printed, we divide by 100 to return the value to meters.

    Regarding groundspeed, the GPS calculates groundspeed by looking at how fast the latitude and longitude is changing.

  • NMEA altitude is in feet (or meters, depending on your unit's settings) above mean sea level, your being on Level 7 has absolutely nothing to do with that - that's altitude above ground level.
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Shivchand Jaysaval liked Shivchand Jaysaval's profile
Aug 25