PNI SeaTRAX User Manual
Page 53
PNI Sensor Corporation
DOC#1018154 r02
SeaTRAX User Manual
Page 48
The CalOption values are given below, along with basic descriptions of the options.
Full-Range Calibration - magnetic only (10
d
= 0A
h
)
Recommended calibration method when >45° of tilt is possible.
2D Calibration - magnetic only (20
d
= 14
h
)
Recommended when the available tilt range is limited to ≤5
°.
Hard-Iron-Only Calibration - magnetic only (30
d
= 1E
h
)
Recalibrates the hard iron offset for a prior calibration. If the local field hard iron
distortion has changed, this calibration can bring the module back into specification.
Limited Tilt Range Calibration
– magnetic only (40
d
= 28
h
)
Recommended calibration method when >5° of tilt calibration is available, but tilt is
restricted to <45°. (i.e. Full-Range Calibration is not possible.)
Accelerometer-Only Calibration (100
d
= 64
h
)
Select this when only accelerometer calibration will be performed.
Accelerometer and Magnetic Calibration (110
d
= 6E
h
)
Selected when magnetic and accelerometer calibration will be done simultaneously.
Below is a complete sample packet to start a 2D Calibration (kStartCal):
Heading, pitch and roll information is output via the kGetDataResp frame during the
calibration process. This feature provides guidance during the calibration regarding
calibration sample point coverage. During calibration, in the kGetDataResp frame, the
number of data components is set to be 3 and then followed by the data component ID-
value pairs. The sequence of the component IDs are kHeading, kPitch and kRoll.
The steps below provide an example of the steps to perform a user calibration.
Using the kSetConfig command, set kUserCalAutoSampling. FALSE allows for
more direct control, but TRUE may be more convenient.
Using the kSetConfig command, establish the coefficient set number for the new
calibration coefficient by setting the value for kMagCoeffSet (value 0-7) and/or
kAccelCoeffSet (value 0-2).
Using the kSetConfig command again, set kUserCalNumPoints to the appropriate
number of calibration points.
00 09
Frame ID
0A
ByteCount
00 00
CalOption
(MSBs)
CalOption
(2D Calibration)
00 14
5C F9
Checksum