Trimble Outdoors SK8 - Manual (Page 127)

Lassen-SK8 Embedded GPS Module A-63
Trimble Standard Interface Protocol
*
Note – Version 7.52 firmware supports only WGS-84 datum.
To request the current datum setting, the command packet contains only one data byte as
shown in Table A-73. Report Packet
0x 8F-15 is returned.
To change to one of the internally held datum the packet must contain exactly 2 bytes
representing the integer value of the index of the datum desired:
*
Note – To request the current datum, send Packet 8E-15 with no data bytes.
Alternatively, the unit will accept a 42 byte input packet containing 6 double precision
floating point value representing the ellipse. The first 3 are DX, DY and DZ which
represent an offset in meters from the ECEF origin for the ellipse. The fourth parameter is
the semi-major axis of the ellipse (called the a-axis) and is also in meters. The fifth
parameter is the eccentricity squared of the ellipse and is dimensionless.
I
Caution – The GPS receiver does not perform an integrity check on the datum values. If unusual
inputs are used, the output will be equally unusual.
Table A-72. Command Packet 0x8E-15 Field Descriptions
Byte Type Value
0 Superpacket ID 0 x 15
Table A-73. Command Packet 0x8E-15 Datum Index Field Descriptions
Byte Type Value
0 Superpacket ID 0 x 15
1-2 INTEGER Datum index
Table A-74. Command Packet 0x8E-15 Eccentricity of the Ellipse
Parameter Field Descriptions
Byte Type Value Units
0 Superpacket
ID 0 x 15
1-8 DOUBLE DX m
9-16 DOUBLE DY m
17-24 DOUBLE DZ m