NMEA 0183 standard GPS Fix Data.


<1>    UTC of position, in the form hhmmss
<2>    Latitude, to the nearest .0001 minute
<3>    N if field <2> is North Latitude S if field <2> is South Latitude
<4>    Longitude, to the nearest .0001 minute
<5>    E if field <4> is East Longitude W if field <4> is West Longitude
<6>    GPS quality indicator:
           0 = Fix not available or invalid
           1 = GPS SPS Mode, fix valid
           2 = Differential GPS, SPS Mode, fix valid
           3 = GPS PPS Mode, fix valid
           4 = Real Time Kinematic (RTK)
           5 = Float RTK
           6 = Estimated (dead reckoning) Mode
           7 = Manual Input Mode
           8 = Simulator Mode
<7>    Number of satellites in use, 0-12
<8>    Horizontal dilution of precision (HDOP)
<9>    Altitude relative to mean-sea-level (geoid), meters (to the nearest whole meter)
<10>  M
<11>  Geoidal separation, meters (to the nearest whole meter). 
durga BABU
11/25/2016 09:02:36 pm

i want to wirite a cprogram to validate the gps packet,at the 14 field there their is no delimter how can i seperate checksum for my calculations

12/4/2016 03:24:30 am

As you know checksum starts with "*" so before you start the checksum calculation check the incoming sentence to see if a checksum is precent. (check if * is included in the sentence and if you function finds then remove from sentence the star and the next two bytes).
Now you have a sentence without checksum ready for the calculation function


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