I have designed a unit for our RV that reads several sensors and displays driving, leveling, distance to front objects, engine and atmos conditions, etc.
I have added a QMC5883L and am only using the X axis for compass. Included a calibration routine in the sketch. Everything works perfectly on the bench. The box (with QMC588L and NANO) will be located under the front shroud. It will be mounted near metal of course (with the engine about 3 feet away.) My question(s) is: After install if I do the calibration routine while driving in a circle, will that get me close? Assuming so, how often does this routine have to be done? (I will save the corrections to Eprom to be read at each startup)
I would guess? that all vehicles with compasses have similar mounting issues near metal. Does calibration adust for this and how often do I have to do it? Thanks