Campbell Scientific RTDAQ Software - Manual (Page 260)

Section 9. Calibration and Zeroing
variables would be used after the FieldCal instruction in the CRBasic program
to ensure that regular measurements return a calibrated value.
To perform a zero basis point calibration, use an argument of 4 (the number
four) for the calibration type in the FieldCal instruction of your CRBasic
program.
The syntax would be:
FieldCal (4,RTS(),3,0,ZeroState(),Mode,0,1,Avg)
Using the instruction shown above, when a calibration is performed the current
values of the variable array, RTS, will be loaded into the variable array,
ZeroState.
In the Calibration Wizard, choose “Zero” as the type of
calibration to perform when doing a Zero Basis Point
Calibration. NOTE
9.4 Performing a Manual Calibration
9.4.1 How to Use the Mode Variable for Calibration Status and
Control
To perform a manual calibration (without use of the RTDAQ Calibration
Wizard) on a FieldCal enabled program running in a datalogger, it is necessary
to understand the function of the mode variable that is used as an argument of
the FieldCal instruction.
In a CRBasic calibration program, a mode variable is declared and associated
with a particular FieldCal instruction, thereby associating it with the
measurement to be calibrated.
Most values of the mode variable represent the status of the calibration for that
affected measurement. A few values of the mode variable are set by the user of
the datalogger to instruct the program to proceed with calibrations.
The following values of the mode variable give the status of the calibration:
0 No calibration has been performed since program start
2 Calibration in progress OR first stage of two-point calibration in progress
3 Waiting for second stage of two-point calibration to begin
5 Second stage of two-point calibration in progress
6 Calibration complete
-1 Calibration error
-2 Measurement range error
-3 Error with the value used as the Reps argument in the FieldCal instruction.
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