Example Format Document

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Data Format Description: These files contain GGA and ZDA strings preceded by decimal unix system timestamps. Each lines alternates the NMEA tag used.

Standards Followed: NMEA0183, Unix Epoch Time

Useful References: 
https://receiverhelp.trimble.com/alloy-gnss/en-us/NMEA-0183messages_GGA.html
https://receiverhelp.trimble.com/alloy-gnss/en-us/NMEA-0183messages_ZDA.html

Sample Rate: 1Hz

Data line column descriptions (one description per unique line format):

    Example Line: 1724619324.23 $GPGGA,123519,4807.038,N,01131.000,E,1,08,*47
    where:
	  1724619324.23    Unix Epoch Time (Decimal seconds since 00:00:00 UTC - January 1, 1970 minus leap seconds)
	  $GPGGA           NMEA0183 standard tag: essential fix data which provide 3D location and quality data.
	  123519           Fix taken at 12:35:19 UTC
	  4807.038, N      Latitude 48 degrees 07.038 minutes North
	  01131.000,E      Longitude 11 degrees 31.000 minutes East
	  1                Fix quality: 0 = fix not available or invalid
				 1 = GPS Standard Positioning Service (SPS) mode, fix valid
				 2 = differential GPS (DGPS), SPS mode, fix valid
				 3 = GPS Precise Point Positioning (PPS) mode, fix valid
	  08              Number of satellites being tracked
	  *47             Checksum, always begins with *

    Example Line: 1724619324.23 $GPZDA,201530.18,04,07,2002,01,00*60
    where:
	  1724619324.23  Unix Epoch Time (Decimal seconds since 00:00:00 UTC - January 1, 1970 minus leap seconds)
	  $GPZDA         NMEA0183 standard tag: Date and Time
	  201530.18      hours, minutes, and seconds expressed as hhmmss.ss
			      20      2-digit hour [24 hour clock]
			      15      2-digit minute
			      30.18   decimal seconds
	  04            2-digit day,
	  07            2-digit month
	  2002          4-digit year
	  01            2-digit local timezone hours: -13 to 13
	  00            2-digit local timezone minutes: 0 to 59
	  *60           Checksum, begins with *

Example File Contents:

    1724619319.23 $GPGGA,  123519,4807.038,N,01131.000,E,1,08,0.9,545.4,M,46.9,M,,*47
    1724619320.23 $GPZDA,  123520.23,25,08,2024,00,00*6B
    1724619321.23 $GPGGA,  123521,4807.078,N,01131.060,E,1,10,0.7,547.0,M,46.9,M,,*4F
    1724619322.23 $GPZDA,  123522.23,25,08,2024,00,00*69
    1724619323.23 $GPGGA,  123523,4807.118,N,01131.120,E,1,08,0.8,548.6,M,46.9,M,,*40
    1724619324.23 $GPZDA,  123524.23,25,08,2024,00,00*6F
    1724619325.23 $GPGGA,  123525,4807.158,N,01131.180,E,1,10,0.9,550.2,M,46.9,M,,*4D
    1724619326.23 $GPZDA,  123526.23,25,08,2024,00,00*6D
    1724619327.23 $GPGGA,  123527,4807.198,N,01131.240,E,1,08,0.7,551.8,M,46.9,M,,*40
    1724619328.23 $GPZDA,  123528.23,25,08,2024,00,00*63
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