BeginReadMultiple

[qmd]

Hi,

Just hoping to see a sample of how to use BeginReadMultiple()
Trying to work out how I can build my list of tags to read.

Thanks!

[qmd]

I managed to write the code for this to compile, but don't think it's correct as I am not ever getting a DataReceived event. Any idea why?
Code I used to read is:

        Dim result As New Integer

        Dim DintTags As New List(Of Drivers.CLXAddressRead)
        DintTags.Add(New Drivers.CLXAddressRead("DINT1"))
        DintTags.Add(New Drivers.CLXAddressRead("DINT2"))
        DintTags.Add(New Drivers.CLXAddressRead("DINT3"))
        DintTags.Add(New Drivers.CLXAddressRead("DINT4"))
        DintTags.Add(New Drivers.CLXAddressRead("DINT5"))
        result = EthernetIPforMicro800Com1.BeginReadMultiple(DintTags)
        Console.WriteLine("result: " & result)

[Archie]

The BeginReadMultiple will fire the event, but the values are not extracted to e.Values

You will have to manually extract it like this:

Code: [Select]

    Private Sub EthernetIPforCLXCom1_DataReceived_1(sender As Object, e As Drivers.Common.PlcComEventArgs) Handles EthernetIPforCLXCom1.DataReceived
        Dim x As Int16 = BitConverter.ToInt32(e.RawData, 0)
        MsgBox(x)
    End Sub


[Archie]

My solution above is not correct. I'm investigating further into this

[Archie]

You will need to specify the NumberOfElements:

Code: [Select]

        Dim addresses As New List(Of MfgControl.AdvancedHMI.Drivers.CLXAddressRead)
        Dim adr As New MfgControl.AdvancedHMI.Drivers.CLXAddressRead("DINTTag")
        adr.NumberOfElements = 1
        addresses.Add(adr)
        EthernetIPforCLXCom1.BeginReadMultiple(addresses)


[qmd]

Does this work on MicroLogix?

I have used your code:

Code: [Select]

        Dim addresses As New List(Of MfgControl.AdvancedHMI.Drivers.CLXAddressRead)
        Dim adr As New MfgControl.AdvancedHMI.Drivers.CLXAddressRead("DINT1")
        adr.NumberOfElements = 1

        addresses.Add(adr)
        EthernetIPforMicro800Com1.BeginReadMultiple(addresses)

And get this exception: A first chance exception of type 'System.ArgumentOutOfRangeException' occurred in mscorlib.dll

I can connect to tags with a subscription via the visual toolbox items though.

[Archie]

The Mirco800 series does not support Multi Service Requests.

[qmd]

OK thanks for your very prompt responses.