ashtech DG16 Reference Manual page 159

positioning mode, and, in 2-D mode, whether the altitude used is the most recently
computed "good" altitude or a fixed altitude value set by the ALT command. Enter
0, 1, 2, or 3 for d1. You can view the current position mode by entering the query
command $PASHQ,PAR and checking the PMD field. See the section in chapter
3 entitled "Position Modes" for more information on the position mode settings.
• Position Mode 0: Manual 3-D Mode
Sets the receiver for 3-D position computation. The receiver must be
tracking a minimum of four satellites in order to compute a position.
• Position Mode 1: Automatic 3-D Mode
The receiver must track a minimum of three satellites to compute a
position. With three satellites, latitude and longitude are computed and
altitude is held to a fixed value (2-D positioning). With four satellites or
more, altitude is computed (3-D positioning).
• Position Mode 2: Manual 2-D Mode
The receiver must track a minimum of three satellites to compute a
position. This mode locks the receiver to 2-D positioning, meaning latitude
and longitude are computed and altitude is always held fixed regardless of
the number of satellites tracked.
• Position Mode 3: Automatic 3-D Mode
The receiver must track a minimum of three satellites to compute a
position. With 3 satellites, longitude and latitude are computed and altitude
is held fixed (2-D positioning). With 4 satellites, altitude is computed (3-D
positioning) unless the calculated HDOP value is greater than HDOP
mask setting.
Example
Enter the following command to select Position Mode 3:
$PASHS,PMD,3
Receiver Commands
DEFAULT SETTING
PMD—1
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