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C.2 Using CONFigure with a Math Operation
The following example uses CONFigure with the dBm math operation.The CONFigure command
gives you a little more programming flexibility than the MEASure? command. This allows you
to
“incrementally” change the multimeter’s config
uration.
LISTING C.2.
Set the startup object for a Windows application to
Sub Main
.
Add a Reference to the
“
VISA Library
”
.
The sample application requires the following referece: C:\WINDOWS\system32\
visa32.dll
.
Public Declare Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As Long)
Sub main()
Rem #########################################
Rem
Rem Using NI-VISA library visa32.dll
Rem
Rem Set sample count 5 configuration and
Rem read the trigger
Rem
Rem #########################################
Dim stat As ViStatus
Dim dfltRM As ViSession
Dim sesn As ViSession
Dim fList As ViFindList
Dim desc As String * VI_FIND_BUFLEN
Dim nList As Long
Dim ret As Long
Dim readin As String * 128
Dim i As Integer ' Array index
stat = viOpenDefaultRM(dfltRM)
If (stat < VI_SUCCESS) Then
'Rem Error initializing VISA ... exiting
MsgBox "USB-TMC resource not found.", vbExclamation, "DL-1060 multimeter device test"
Exit Sub
End If
Rem Find all DL-1060 USB-TMC instruments in the system
stat = viFindRsrc(dfltRM, "USB[0-9]*::0x098F::0x2062::?*INSTR", fList, nList, desc)
If (stat < VI_SUCCESS) Then
'Rem Error finding resources ... exiting
MsgBox "DL-1060 device not found.", vbExclamation, "DL-1060 multimeter device test"
viClose (dfltRM)
Exit Sub
End If
Rem Open a session to each and determine if it matches
stat = viOpen(dfltRM, desc, VI_NULL, VI_NULL, sesn)
If (stat < VI_SUCCESS) Then
MsgBox "Open device failed.", vbExclamation, "DL-1060 multimeter device test"
stat = viClose(fList)
Exit Sub
End If
Rem send reset command '*RST' -- reset DL-1060
stat = viWrite(sesn, "*RST", 4, ret)
