PNI FieldForce Trax - Manual (Page 59)

PNI Sensor Corporation DOC#1016505 r06
TRAX User Manual Page 55
kFactoryAccelCoeffDone (frame ID 37
d
)
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
d
)
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
d
)
This frame queries the TRAX functional mode. The frame has no payload.
kGetFunctionalModeResp (frame ID 81
d
)
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)