Campbell Scientific CR9000X Measurement and Control System - Manual (Page 157)

Section 4. CRBasic – Native Language Programming
In most applications, it is highly recommended to perform background
calibration in the SlowSequence Scan. If calibration is not done as part of the
program, a typical shift in the calibration is 0.01 % per degree C change from
the temperature at which the program compile calibration occurred.
See Section 9.2 DataLogger Status/Control for information on Calibrate &
BiasComp.
Example program 4.2.9-5 has a SlowSequence program area with a
Scan/NextScan bracketing the Calibrate and BiasComp instructions.
Example Program 4.2.9-5
Public Accel
DataTable (Main1,1,-1)
DataInterval (0,0,0,100) 'Synch the output rate to the SubScan rate
Sample (1,Accel,IEEE4)
EndTable
'PROGRAM: MAIN SEQUENCE
BeginProg
Scan (1,Sec,1000000,0) 'Scan once a second, 1,000,000 Scan buffers
SubScan (1,mSec,1000) '1000/1 SubScan/Scan ratio
VoltFilt (Accel(),1,mV200,5,1,2,7,1.0,0)
CallTable Main1 'Call Table from SubScan to output at its rate.
NextSubScan
NextScan
'LOW PRIORITY BACKGROUND SEQUENCE
SlowSequence 'Used for slow measurements/Background Calibration
Scan(10,Sec,0,0) 'Scan once every 10 seconds
Calibrate 'Corrects ADC offset and gain
BiasComp 'Corrects ADC bias current
Next Scan 'Loop up for the next scan
EndProg
4.2.10 CRBasic Measurement Instructions
CRBasic includes instructions specifically designed for making measurements
and storing the result to variables. Each instruction has a keyword name and a
series of parameters that contain the information needed to complete the
measurement. Measurement instructions must be placed within a
Scan/NextScan construct. This section will cover a couple measurement
instructions to give examples on how to set up a program.
See Section 7 Measurement Instructions for information on Measurement
instructions.
4.2.10.1 ModuleTemp Measurement Instruction
The instruction for measuring the temperature of the CR9050 modules reference
PRT is: ModuleTemp (Dest,Reps,Slot,Integ)
ModuleTemp is the keyword name of the instruction. The four parameters
associated with ModuleTemp are:
Destination: the name of the variable in which to put the temperature
Reps:
the number of modules you want to measure the PRTs of,
Slot the slot number where the first module resides, and
Integration: the length of time to integrate the measurement.
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