Owner manual
PNI Sensor Corporation    DOC#1016505 r06 
TRAX User Manual  Page 55 
kFactoryAccelCoeffDone (frame ID 37
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) 
This frame is the response to kFactoryAccelCoeff frame. The frame has no payload. 
7.7  Compass Mode Commands 
The TRAX normally operates in AHRS Mode, which uses a proprietary Kalman algorithm to 
fuse the  inputs of its 3-axis gyroscope, 3-axis accelerometer,  and 3-axis magnetometer. 
However, the user can place the TRAX in Compass Mode, wherein it only uses the inputs 
from the accelerometer and magnetometer to establish heading, pitch, and roll.  In this case 
the TRAX operates very similarly to PNI’s TCM electronic compass. 
There are a couple of reasons it may be desirable to place the TRAX in Compass Mode.  As 
previously mentioned, it  is  necessary to  place  the  TRAX in  Compass  Mode to  perform  a 
calibration.    Additionally,  if  a  static  measurement  is  to  be  made  in  a  known  clean  local 
magnetic field, then a somewhat higher level of accuracy is achievable in Compass Mode. 
Also, by placing the TRAX in Compass Mode it can subsequently be placed into Sleep Mode 
which will significantly reduce power consumption when not taking measurements. 
7.7.1  Switching Functional Mode 
kSetFunctionalMode (frame ID 79
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) 
This frame establishes  whether  the TRAX operates  in AHRS  Mode or  Compass 
Mode.  The frame has  a  one byte payload.  The payload  byte  is  “0”  to  operate  in 
Compass Mode and “1” to operate in AHRS Mode. The default is “1”. 
Sending the kSave command after changing the mode  will save the new setting  in 
non-volatile memory. 
kGetFunctionalMode (frame ID 80
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) 
This frame queries the TRAX functional mode. The frame has no payload. 
kGetFunctionalModeResp (frame ID 81
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) 
This is the response of kGetFunctionalMode, and it has the same payload definition 
as kSetFunctionalMode. 
FunctionalMode 
UInt8 
Payload 
FunctionalMode Payload Value: 
“0”: Compass Mode 
“1”: AHRS Mode (default) 










