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+The sensor is the PmodCMPS2 compass sensor with
+the 3D magnetometer chip MMC34160PJ
+Data sheet
+https://download.mikroe.com/documents/datasheets/MMC3416xPJ_Rev_C_2013_10_30.pdf
+
+On the earth surface the world magnetic field points towards the north and
+in level with the horizon at the equador. Further north the field starts 
+pointing downwards. In southern Europe it points downwards with inclination
+60 degrees. In Scandinavia it points downwards with inclination 75 degrees. 
+At the north pole it points straight down with inclination 90 degrees. 
+
+The declination is the difference between geaographic and magnetic north pole.
+The declination depends where and when you are observing the field. 
+
+The values for Helsinki in December 2021 ( Model used WMM-2020 
+https://www.ngdc.noaa.gov/geomag/calculators/magcalc.shtml#igrfwmm  ) 
+Declination 9 degr 45 min 
+Inclination 73 degr 35 min
+North component 14572 nT = 146 milli Gaus
+East component 2505 nT = 25 milli Gaus
+Vertical component 50222 nT = 502 milli Gaus
+Total field 52353 nT = 524 milli Gaus
+ 
+Connect: 
+L432KC --  PmodCMPS2
+PA_9   --  SCL
+PA_10  --  SDA
+GND    --  GND
+3V3    --  VCC
+Set the jumpers SDA and SCL on the PmodCMPS2. 
+
+Timo Karppinen Apache-2.0
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