using the serial port class in VB

using the serial port class in VB

• mike_dowler

  Private WithEvents objPort As System.IO.Ports.SerialPort
      Private Sub frmGPSReader_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
                      If InitComPort("COM1") Then
                          If OpenComPort() Then
                              blnReturn = True
                          End If
                      End If
      End Sub
      Friend Function InitComPort(ByVal strPortName As String) As Boolean
  
          Dim blnOK As Boolean = False
  
          Try
              If objPort Is Nothing Then
                  objPort = New SerialPort(strPortName, 4800)
              End If
  
              objPort.ReceivedBytesThreshold = 512 '<- set limit before objPort_DataReceived event fires
  
              blnOK = True
  
          Catch ex As Exception
              blnOK = False
  
          End Try
  
          Return blnOK
  
      End Function
      Friend Function OpenComPort() As Boolean
  
          Dim blnOK As Boolean = False
  
          Try
              If objPort Is Nothing Then
                  blnOK = False
              Else
                  If objPort.IsOpen Then
                      blnOK = True
                  Else
                      objPort.Open()
                      blnOK = objPort.IsOpen
  
                  End If
              End If
  
          Catch ex As Exception
              blnOK = False
  
          End Try
  
          Return blnOK
  
  WARNING: objPort.ReadBufferSize = 8192 <- Has no effect on my device, max is 2047
  
      Private Sub objPort_DataReceived(ByVal sender As Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) Handles objPort.DataReceived
  
          Dim strGPSData as String = objPort.ReadExisting
  
      End Sub
  
  voila!
  
  

• Display Name*

  I worked on a VS2005  program many months ago to explore and use the com serial class with desktop CF2 (VS2005 Beta 1).  I  developed from a sample I found elsewhere.  It fully exercises the desktop serial class.
  
  I then ported it to  a smartdevice but ran into one problem.
  
  With the full FW you can get a list of all available COM ports.  This then is used as a dropdownlist to choose the COM port.  This capability is not available under CF.  It could be replaced with a manually entered list, but I haven't added this yet.
  
  You can get the projects from http://babbage.ece.rmit.edu.au/downloads  and use that as a start.
  
  

• David PROVOST

  Hi Bruce,
  
  You can find a sample of managed serial port communication here:
  
  http://www.codeproject.com/csharp/SerialCommunication.asp
  
  The project is in C#, but you should be able to convert it to VB easily.
  
  In NETCF V2 Beta 2, we added the SerialPort.GetPortNames() method that returns an array of serial port names for the current device. You can find the documentation here:
  
  http://msdn2.microsoft.com/en-us/library/0st1yts8
  
  Cheers,
  Anthony Wong [MSFT]
  

• FMartins

  I think it was the GetPortNames() method that wasn't available in the CF.
  
• using the serial port class in VB