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Tips and questions relating to the GPS modules from SFE
By NleahciM
My understanding of GPS modules is that they gave you position (including altitude) and velocity. Looking over the EM-406 datasheet though I noticed that it also gives a heading. Is this heading just the direction that the velocity is? Surely it isn't a compass sort of heading? Thanks.
By dpaton
I haven't checked, but if it's like every other GPS module I've ever worked with, yes, it's the angle of the velocity vector. Closer to english, it's the direction of travel, and is most accurate when traveling faster than a few mph.