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100 GG Surveyor GPS+GLONASS Reference Manual
PPO: Point Positioning
$PASHS,PPO,c
Enable/disable point positioning mode, where c is either Y (enable) or N (disable).
Point positioning is an averaging algorithm that will improve the stand-alone
accuracy of a static point after about 4 hours.
Example: Enable point positioning mode
$PASHS,PPO,Y <Enter>
PPS: 1 PPS Pulse Output
$PASHS,PPS,f1,f2,c3
The GG Surveyor GPS board can generate 1 PPS pulse (page 31) with programmable
period and offset. 1 PPS is generated by default once every second with its rising or
falling edge synchronized to the GPS system time (or UTC + 3 hours if SYS is set to
GLO). The PPS set command allows you to change the period and the offset of the
pulse, where Table 6.23 outlines the parameters:
The precision of the PPS signal is 70 nano seconds in stand-alone mode with SA
active, and 45 nano seconds in differential mode.
Example: Set 1PPS to a period of 2 seconds an offset of 500ms, and synchronize the
rising edge of the pulse with GPS time.
$PASHS,PPS,.2.0,+500,R<Enter>
$PASHQ,PPS,x
The associated query command is $PASHQ,PPS,x, where x is the optional output
port.
Example: Query 1PPS parameters to port A.
$PASHQ,PPS,A<Enter>
Table 6.23: PPS Parameters
Field Description
f1 1PPS period in seconds with a range between 0.2 and 99, depending upon
the receiver update rate, which depends upon the position update or raw
data update options
f2 Offset from GPS system time in milliseconds, with 100ns resolution (range
between -999.9999 and +999.9999)
c3 R (Synchronize the rising edge of the pulse with GPS system time), or F
(synchronize the falling edge of the pulse with GPS system time).