Orolia GSG-5 Series, User Manual With Scpi Manual, Page: 378 / 392

sour:scen:elapsedTime?
*OPC?
...
syst:err?
6.6.1.3 Underflow and Overflow
Underflow and overflow errors are signaled by the GSG unit. The possible errors which can
be retrieved with the command
SYSTem:ERRor[:NEXT]?
.
The relevant error codes are:
-193 “RSG command overflow occurred.”
-194 “RSG command underflow detected.”
The GSG unit will flag the overflow error in a situation where redundant or conflicting
information is given during the same epoch, i.e., giving position both using the
SOURce:SCENario:ECEFPOSition
as well as the
SOURce:SCENario:POSition
com-
mand would trigger an overflow error. The overflow error will always trigger by default in
such situations. Would redundant data come in the later commands will overwrite the
earlier information.
The underflow error detection is by default not used but has to be explicitly set ON using
the command listed in previous chapter. When in usage GSG will require at least one RSG
command to come in every epoch (100 ms). Would there be an out take in this command
stream GSG will set the error flag that indicates, e.g., problems in communication with host.
6.6.1.4 Best Practices
In a high rate control setup it is recommended that queries are avoided or kept to a min-
imum. The reason for this is to reserve the maximum time for the controlling commands.
The user must pay attention that the actual data sent in is smooth. The signal tracking in
GNSS receivers are very sensitive to high dynamics and won’t be able to track signals if pos-
ition changes with several meters during one epoch. Hence it should be preferred to
change user position using the more dynamic speed and acceleration commands, as a
‘blunt’ position change has to be smooth and small for the receivers to be able to follow.
Hence using position/speed commands you only need to send commands when these
parameter values changes. Relying on position commands you are recommended/forced
to utilize 10 Hz commands to make the movements smooth enough for receivers to follow.
6.6.1.5 Limitations
Communication over GPIB is not currently working for RSG commands – syn-
chronization fails.
362 User Manual GSG-5/6 Series Rev. 27
6.6 Programming