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Chapter 6 Application Programs
Program Listings
6
Program Listings
Example: A Simple Sine Waveform
This program (found in the “Examples\chapter6\SimpleSine” subdirectory on the CD-
ROM) selects the function as “sine,” and then sets the frequency, amplitude and offset of
the waveform.
Private Sub cmdSimpleSine_Click()
Dim io_mgr As VisaComLib.ResourceManager
Dim Fgen As VisaComLib.FormattedIO488
Set io_mgr = New VisaComLib.ResourceManager
Set Fgen = New VisaComLib.FormattedIO488
Set Fgen.IO = io_mgr.Open(txtIO.Text)
On Error GoTo MyError
' This program sets up a waveform by selecting the waveshape
' and adjusting the frequency, amplitude, and offset.
With Fgen
.WriteString "*RST" ' Reset the function generator
.IO.Clear ' Clear errors and status registers
.WriteString "FUNCtion SINusoid" ' Select waveshape
' Other options are SQUare, RAMP, PULSe, NOISe, DC, and USER
.WriteString "OUTPut:LOAD 50" ' Set the load impedance in Ohms
' (50 Ohms default)
' May also be INFinity, as when using oscilloscope or DMM
.WriteString "FREQuency 2500" ' Set the frequency.
.WriteString "VOLTage 1.2" ' Set the amplitude in Vpp.
' Also see VOLTage:UNIT
.WriteString "VOLTage:OFFSet 0.4" ' Set the offset in Volts
' Voltage may also be set as VOLTage:HIGH and VOLTage:LOW for low level
' and high level
.WriteString "OUTPut ON" ' Turn on the instrument output
End With
Exit Sub
MyError:
txtError = Err.Description & vbCrLf
Resume Next
End Sub