<System.Runtime.InteropServices.DllImport("dllname.dll", _
      EntryPoint:="InitHardware")> _
    Public Shared Sub Inithardware(ByVal a As Integer)
    End Sub
    <System.Runtime.InteropServices.DllImport("dllname.dll", _
      EntryPoint:="IsHardwareConnected")> _
    Public Shared Function IsHardwareConnected() As Integer
    End Function

InitHardware(Me.Handle)
If IsHardwareConnected() <> 0 Then
     '....code
else
     'starte timer
end if