V102 GPS Compass User Guide
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message. The default value of this constant is 0.5 seconds of smoothing.
Increasing the time constant increases the level of pitch smoothing and
increases lag.
Rate of Turn (ROT) time constant:
Use the $JATT,HRTAU command to
adjust the level of responsiveness of the ROT measurement provided in the
$GPROT message. The default value of this constant is 2.0 seconds of
smoothing. Increasing the time constant increases the level of ROT
smoothing.
Course Over Ground (COG) time constant:
Use the $JATT,COGTAU
command to adjust the level of responsiveness of the COG measurement
provided in the $GPVTG message. The default value of this constant is
0.0 seconds of smoothing. Increasing the time constant increases the level
of COG smoothing. COG is computed using only the primary GPS antenna
and its accuracy depends upon the speed of the vessel (noise is proportional
to 1/speed). This value is invalid when the vessel is stationary, as tiny
movements due to calculation inaccuracies are not representative of a
vessel’s movement.
Speed time constant:
Use the $JATT,SPDTAU command to adjust the
level of responsiveness of the speed measurement provided in the $GPVTG
message. The default value of this constant is 0.0 seconds of smoothing.
Increasing the time constant increases the level of speed measurement
smoothing.
Watchdog
The watchdog is a timer that is controlled by the software that monitors if
the heading is lost. The watchdog software is compliant with IEC 60495.
Summary of Contents for V102 G
Page 1: ...V102 GPS Compass User Guide Part No 875 0276 000 Rev C1 ...
Page 6: ...Chapter 1 Introduction Overview Parts List ...
Page 9: ......
Page 32: ...Chapter 3 Operation GPS Overview V102 Overview Common Commands and Messages ...
Page 46: ...Appendix A Troubleshooting ...
Page 50: ...Appendix B Specifications ...
Page 60: ...www hemispheregps com ...
