Campbell CR9000, Instruction Manual

Page: 143 / 218

Section 7. Measurement Instructions
7-29
The following example program measures 6 channels on the CR9052DC using the VoltFilt instruction.
' CR9052 example program #1
'
'
Measure six channels at 1 kHz on +/- 5000 mV range with 5-Volt excitation.
‘ Sample ratio is 2.5: top of pass band is 1 kHz / 2.5 = 400 Hz.
‘ CR9052 is in slot 8.
‘ Turn on flag 1 on to save instantaneous data to output table.
Public sig_in (6)
units sig_in = mV
Public flag (1)
'------------------- Data Tables -------------
DataTable (FiltData, flag (1), -1)
' save to final storage if flag (1) = True
Sample (6, sig_in(1),IEEE4)
EndTable
'------------------- Program ---------------
BeginProg
Scan(1, msec, 0,0)
' VoltFilt (Destination, Reps, Range, Fslot, Chan, FiltOption, Excitation, Mult, Offset)
VoltFilt (sig_in(1), 6, mV5000, 8, 1, 2, 5, 1.0, 0.0)
CallTable FiltData
Next Scan
EndProg
SubScan (SubInterval, Units, SubRatio)
The SubScan instruction makes it possible to measure CR9052DC inputs at
one rate and measurements on other modules at a slower rate, all within the
same scan.
Parameter
& Data Type
Enter
SUBSCAN INSTRUCTION PARAMETERS
SubInterval
Constant
The time interval at which to run the subscan. The interval must be one of the valid intervals
for the CR9052 module: 20, 40, 100, 200, or 400 microseconds or 1, 2, 4, 10, 20, 40, 100, or
200 milliseconds. When used with the CR9052 Filter Module, the interval of the scan that
contains the SubScan must be an integral multiple of the SubScan interval.
Units
The units for the Interval
Constant
Alpha
Code Numeric
Code
Units
USEC 0 Microseconds
MSEC 1 Milliseconds
SubRatio
Constant
The subscan will run SubRatio times each time the scan runs. When SubScan is used with the
CR9052 Filter Module (the only use as of March 2001) this parameter is redundant but must
be entered anyway. (The Scan interval must be an integral multiple of the SubScan interval or
a compile error will occur. SubRatio is the ratio between the scan interval and the subscan
interval.)