Trimble Outdoors THUNDERBOLT 64057-00-ENG - Manual (Page 46)

A Trimble Standard Interface Protocol
44 Trimble ThunderBolt E GPS Disciplined Clock User Guide
Command Packet 0x31: Accurate Initial Position (XYZ Cartesian ECEF)
This packet provides an accurate initial position to the GPS receiver in XYZ
coordinates. Either the single precision or the double precision version of this packet
may be used, however, we recommend using the double precision version for greatest
accuracy. ThunderBolt E uses this position for performing time-only fixes. If a survey is
in progress when this command is sent, the survey is aborted and this position data is
used immediately. ThunderBolt E will automatically switch to the Over-Determined
Timing mode when this command is issued. Note that this position is not
automatically saved to flash memory. If you want to save this position, first set the
position, wait at least 2 seconds and then use packet 0x8E-A6 to save the position.
Command Packet 0x31 Data Format (single precision)
Command Packet 0x31 Data Format (double precision)
Command Packet 0x32: Accurate Initial Position (Latitude, Longitude,
Altitude)
This packet provides an accurate initial position to the GPS receiver in latitude,
longitude, and altitude coordinates. Either the single precision or the double precision
version of this packet may be used, however, we recommend using the double
precision version for greatest accuracy. The GPS receiver uses this position for
performing time-only fixes. If a survey is in progress when this command is issued, the
survey is aborted, and this position data is used immediately. The coordinates entered
must be in the WGS-84 datum. ThunderBolt E will automatically switch to the
Over-Determined Timing mode when this command is issued. Note that this position
is not automatically saved to flash memory. If you want to save this position, first set
the position, wait at least 2 seconds and then use packet 0x8E-A6 to save the position.
Note – When converting from degrees to radians use the following value for
p = 3.1415926535898
Byte Item Type Units
0-3 X-axis Single Meters
4-7 Y-axis Single Meters
8-11 Z-axis Single Meters
Byte Item Type Units
0-7 X-axis Double Meters
8-15 Y-axis Double Meters
16-23 Z-axis Double Meters