Question

I’m sending some data to my computer through serial port. Thus, I want to load a VBNet program to be loaded once data arrives at the said port. In other words, the program will be triggered by data arriving at the port.

How can I implement that?

Answer 1

Try this. It assumes 3 bytes will be received. You will need to change it for the number of bytes you will be sending. As Mark suggests, use Process to start the program. Alternatively, you could use Shell.

Imports System.IO.Ports

Public Class COMControl

Private WithEvents comPort As SerialPort

Public Sub New(comPortNumber As Integer)

    comPort = New SerialPort
    With comPort
        .BaudRate = 9600
        .Parity = IO.Ports.Parity.None
        .StopBits = IO.Ports.StopBits.One
        .DataBits = 8
        .PortName = "COM" & comPortNumber.ToString
        .ReceivedBytesThreshold = 3
        .Open()
    End With

End Sub


Private Sub comPort_DataReceived(sender As Object, e As System.IO.Ports.SerialDataReceivedEventArgs) Handles comPort.DataReceived

    If comPort.BytesToRead = 3 Then
        Dim by(comPort.BytesToRead - 1) As Byte

        'Read the bytes from the port...
        comPort.Read(by, 0, comPort.BytesToRead)

        '...into an array of bytes
        Dim byList As New List(Of Byte)
        byList.AddRange(by)

        Dim inp As String = System.Text.Encoding.ASCII.GetString(by)

        Select Case inp

            Case "P01"
                Process.Start("PO1.exe")

            Case "P02"
                Process.Start("PO2.exe")

        End Select

    End If
End Sub
End Class