Calling .DLL Method from Timer_Elapsed

[gonzalioz]

Hi all,

I have a .dll file (Interop.ACTMULTILib.dll) that I use to connect to a PLC. This .dll contains a sub called ReadDeviceBlock2(byval devicename as string, byval size as integer, byref data as short).

My console application startup thingy is a module. When I call this method in my main it works fine, if I call it from another method that was called by main it works as well.

However, it doesn't work when I call it from my Timer_Elapsed sub? I guess this has to do something with threads but I can't figure it out.

Any ideas ? Been staring at it for 2 hours now .


[EDIT]
Timer.Start is called from Main()... maybe that has something to with it?

Module Main

    Private Timer As New System.Timers.Timer
    Private PLC As New ACTMULTILib.ActEasyIF
    Private DataSet As new DataSet

    Private _lanes As New List(Of Lane)

    Public Sub Main()

        LoadDataSet()
        ConnectToPLC()

        Console.WriteLine("Press any key to continue ...")
        Console.ReadKey()
        Console.Clear()

        'This works:
        Dim data As Short
        PLC.ReadDeviceBlock2("D880", 1, data)

        AddHandler Timer.Elapsed, New Timers.ElapsedEventHandler(AddressOf Timer_Elapsed)
        Timer.Interval = 1000
        Timer.Start()

        Console.WriteLine("Press any key to exit ...")
        Console.ReadKey()

    End Sub

    Private Sub Timer_Elapsed(ByVal sender As Object, ByVal e As Timers.ElapsedEventArgs)

        'This doesn't work, it will hang here forever without throwing a error:
        Dim data As Short
        PLC.ReadDeviceBlock2("D880", 1, data)

    End Sub