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Visual Basic 6.0 and modem question

  1. Apr 11, 2004 #1

    Ivan Seeking

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    I am having a first go at integrating a PC based VB application with some other types of industrial computers. I wrote a simple VB routine that calls up the driver [for the PC to Industrial connection] as an executable file. This all works fine. The program dials in, gets the data, and closes the exe with no problem. The problem is that whether or not I actually shell to the exe, the modem intialization string seem to be causing me problems. When I am done I can't get the modem to disconnect. This is what I am doing.

    For dial out:

    If MSComm1.PortOpen = False Then
    Call mnuCommPortOpen_Click
    End If

    MSComm1.Output = "AT &D0 &R1 &B1" & vbCrLf
    DialString = "ATDT" & DialNumber & vbCrLf
    MSComm1.Output = DialString

    Once it connects I set MSComm1.PortOpen = false. I need to do this to free up the port for the other application. After I retrieve the data, I attempt to hang up like this.

    If MSComm1.PortOpen = False Then
    MSComm1.PortOpen = True
    End If

    If MSComm1.PortOpen = True Then
    MSComm1.Output = "+++" & vbCrLf
    MSComm1.Output = "ATH0" & vbCrLf
    MScomm1.Portopen = false
    End If

    My modem control skills really stink and I haven't worked with Basic in a very long time, so I'm not sure if this is a VB problem or a modem control problem. I thought that a simple ATH0 should do it, but something about the intialization prevents this from working. Then I thought that I must have to go back into command mode, so I added the +++, but no good. Does anyone know what's going on?

    Edit: This all uses a standard Hayes compatible, V90 modem
  2. jcsd
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