Campbell Scientific CDM-VW300 Series Dynamic Vibrating-Wire Analyzer System - Manual (Page 94)

Appendix G. CRBasic Program Library
'Offset (shift) to be applied to sensor output frequency
Dim Off(2) = { 0.0, 0.0}
'Steinhart-Hart coefficients [A,B,C] for converting thermistor ohms to
'temperature in Celsius. Specifying zeroes for A,B,C results in a reading in Ohms.
Dim SteinA(2) = { 0.0, 0.0}
Dim SteinB(2) = { 0.0, 0.0}
Dim SteinC(2) = { 0.0, 0.0}
'Rainflow configuration (not used in this program,
'but required as configuration arguments)
Dim RFMB(2) As Long = { 20, 20}
Dim RFAB(2) As Long = { 20, 20}
Dim RFLL(2) = { 400.0, 400.0}
Dim RFHL(2) = {4000.0,4000.0}
Dim RFHY(2) = { 0.005, 0.005}
Dim RFOF(2) As Long = { 100, 100}
'Configure the CDM-VW300 series device
'Use the variable arrays declared above
CDM_VW300Config (0,CPI_ADDR,0,Enable(),Max_AMP(),F_Low(),F_High(), _
OutForm(),Mult(),Off(), SteinA(),SteinB(),SteinC(), _
RFMB(),RFAB(),RFLL(),RFHL(),RFHY(),RFOF())
DataTable (static,true,-1)
'Static Frequency reading (1 Hz output)
Sample (2,StaticFreq(),IEEE4)
'Thermistor reading : Ohms or DegC
Sample (2,Therm(),IEEE4)
'Standard Deviation of dynamic readings
'taken during the most recent second
Sample (2,DynStdDev(),IEEE4)
EndTable
DataTable (dynamic,true,-1)
'Dynamic Frequency (20 Hz output)
Sample (2,Freq(),IEEE4)
'Diagnostic code for the current dynamic reading
Sample (2,Diag(),IEEE4)
EndTable
BeginProg
'20 Hz/50msec scan rate
Scan (50,msec,500,0)
CDM_VW300Dynamic (CPI_ADDR,Freq(),Diag()) 'Get dynamic readings
CallTable dynamic
If TimeIntoInterval (0,1,Sec) Then ' Process static data only once per second
CDM_VW300Static (CPI_ADDR,StaticFreq(),Therm(),DynStdDev()) 'Get static readings
CallTable static
EndIf
NextScan
EndProg
G.1.2 20 Hz Measurement Example — One CDM-VW305, Eight
Channels
'===20Hz-1Device8Ch_4-25===
'CR3000 datalogger
'CDM-VW305 vibrating-wire analyzer
'Program to read 20-Hz dynamic data from one CDM-VW305 analyzer measuring eight channels
'IMPORTANT -- Ensure that the CPI address coded on the following line matches the address
'reported for the attached analyzer in the DevConfig or DVWTool software.
Const CPI_ADDR = 1 '<<<<<<<<<<<<<
Public Freq(8) 'dynamic frequencies
Public Diag(8) As Long 'diagnostic code
Public StaticFreq(8) 'Static (1Hz output) frequencies
Public Therm(8) 'Thermistor readings
G-2