VB.net Implementation

[Anonymous]

Hi,

I am trying to use your DLL in a VB.net application to read and write via modbus to a Schnieder distributed IO device. I have used your sample modbusTCP client app and it successfully returns the input status by reading the holding registers. I call the ReadHoldingRegisters function (modbusclient.ReadHoldingRegisters(5392, 16) in this instance to read address 45392 which is a 16 input module) and I only ever get back an array of all 0s.

My test code is as follows:

Public Class Form1
Public Shared modbusclient As New EasyModbus.ModbusClient("192.168.1.101", 502)

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
    modbusclient.Connect()
    System.Threading.Thread.Sleep(1000)

    If (modbusclient.Connected = True) Then
        Dim Inputs(15) As Integer
        Array.Copy(modbusclient.ReadHoldingRegisters(5392, 16), Inputs, 16)
        modbusclient.Disconnect()
        TextBox1.Text = Inputs(0)
    End If

End Sub

End Class

When I trigger this via a push button on the form and setup a breakpoint after that line, the array shows as all 0's when the LSB (first) bit should be 1 as the input is switched on.

Any ideas?
Do you have sample VB code using this library for reference?

[Rossmann Engineering]

Hi I don't fully understand your code. But you definitelly have to check the mapping of your device, that has to match with your Modbus reading. It sounds to me that your trying to read a Holding Register to determine the state of a digital input, or did I missunderstand something?