When I try to read the magnetic variation, the value does not appear, it appears blank, I use one of the examples that exist in the library and on the website. I do not know why it is, since if I want to get other data from the $GPRMC statement that I use, it does appear, but data 10 and 11 just appear blank. I thought that it could be the module that I use and that with the m7n or the m8n it could be requested, what do you think?
Did you print out the RAW serial messages from your GPS module to the Serial Monitor? If yes, could you post a couple of the messages, preferably after the module has been running for a while and found a couple of satellites. Make sure you include all of the message types that are send by the module.
There are modelling systems that allow you to lookup magnetic declination (its normal name), you can look it up online;Magnetic Declination So presumably with certain base parameters from the GPS constallation the GPS works out the declination, when it knows its location. UBLOX produce 'protocol' specification datasheets for their GPSs, whats included in each standard NMEA sentence and whats not is in there. Try a Google search on 'ublox 6 protocol datasheet'
But, how can I find a module with magnetic declination support? I think I can't read all modules protocol datasheets.
I think I can buy a M8N for testing, it's not a big money lost.
Would it not be constant?
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