ashtech DG14, Reference Manual

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Receiver Commands 161
Receiver Commands
SVP: Include/Exclude Satellites for Position Computations
$PASHS,SVP,c1c2c3…c32
This command includes and excludes specific satellites for use in position
computations, where c is Y (include) or N (exclude). Unlike most of the other set
commands, the c parameters are not separated by commas. A satellite which has
been excluded can still be acquired and tracked, but is not used in computing
positions. All satellites are included for position computation by default. The
parameters c1 through c32 correspond to GPS satellites PRN numbers 1 through
32. It is not necessary to enter a setting for all 32 satellites when using this
command.
Examples
To exclude satellites 10 and 15 from the position computation, you could enter the
following command:
$PASHS,SVP,YYYYYYYYYNYYYYN
This command excludes satellites 10 and 15 from the position computation, but
does not change the settings for satellites 16 through 32
$PASHQ,SVP,[c1]
This command queries the current SVP settings, where c1 is the optional output
serial port. If a port is not specified, the receiver sends the response to the current
port.
$PASHR,SVP
The response message contains the current SVP settings for all 32 satellites. The
format of the response message is nearly identical to the format used in the SVP
set command:
$PASHR,SVP,c1c2c3…c32*hh
Table 6.54 outlines the response message.
Typical SVP message:
$PASHR,SVP,YYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY*0D
Table 6.54. $PASHR,SVP Message Format
Field Description Range
c1...c32 Indicates whether a satellites is included (Y) or
excluded (N) for position computations Y, N
*hh Checksum 2-character hex