SXBlue II GPS Series Technical Reference Manual
88
$>JRAD,1P,OK
4.8.3 $JRAD,1,lat,lon,alt
This command is a derivative of the $JRAD,1,P command. It is normally followed by a
$JRAD,2 command.
This command has the following layout:
$JRAD,1,lat,lon,alt<CR><LF>
Where the data fields in this command are described in the following table.
Data Field
Description
lat
This is the latitude of the reference point in degrees decimal degrees.
lon
This is the longitude of the reference point in degrees decimal degrees.
alt
This is the ellipsoidal height of the reference point in m. (Ellipsoidal height
can be calculated by adding the altitude and geoidal separation, both
available from the GGA sentence. See example below.)
Example of ellipsoidal height calculation:
$GPGGA,173309.00,5101.04028,N,11402.38289,W,2,07,1.4,1071.0,M,-17.8,M,6.0, 0122*48
ellipsoidal height = 1071.0 + (-17.8) = 1053.2 meters
The SXBlue II GPS will reply with the following response:
$>JRAD,lat,lon,alt
Note - Both latitude and longitude must be entered as decimal degrees. The
receiver will not accept the command if there are no decimal places.
4.8.4 $JRAD,2
This command is used to force the receiver to use the new reference point. This
command is normally used following a $JRAD,1 type command.
This command has the following format:
$JRAD,2<CR><LF>
The SXBlue II GPS will reply with the following response:
$>JRAD,2,OK
4.8.5 $JRAD,3
This command is used for two primary purposes. The first is to invoke the Auto-Dif
function once the unit has started up (with the Auto-Dif application active). The second
purpose is to update the Auto-Dif solution using the current position as opposed to the
reference position used by the $JRAD,2 command. This command has the following
format:
$JRAD,3<CR><LF>
