Messages

1

Support Questions / Re: Modbus RTU questions

« on: March 03, 2021, 08:06:04 AM »

I trying to give the user the option to select the Com port through a ComboBox, as well as BaudRate and Modbus slave address.
As far as I understand if I drag n drop the Modbus driver into the form then the connection will be started automatically when the Form loads.
What if I want to start the connection manually after selecting the port, baudrate and slave address for example on button click and also be able to disconnect change comms settings and then connected again.
Do I need to read and write registers connected to BasicLabels manually?

Is there any example project that could help understanding how AdvancedHMI works?

2

Support Questions / Modbus RTU questions

« on: February 28, 2021, 06:35:36 AM »

I use Modbus RTU driver to connect to a Modbus slave.
The addressing scheme of the slave is 0 based so in order to read HR 400050 I have to put the address 400051 in basic label.
Is it possible to setup the AHMI driver to be 0 based as well?

The method modbusRTUCom1.CloseConnection() can be used to close the connection.
How can I reopen it?

3

Application Showcase / Re: Controlling an entire machine as HMI and PLC.

« on: February 07, 2021, 02:02:00 PM »

Hi timryder

So as far as I understand you created "something" like Soft PLC.
I was thinking about for some time but didn't have the C# skillset to create it.
If possible I would like to take a look at your code and how you handle threads.

Thanks
Leonidas

4

Open Discussion / AdvancedHMI as Soft-PLC

« on: January 03, 2019, 06:39:53 AM »

I was wondering how it's possible to use AdvancedHMI as Soft PLC.
I understand all the real-time restrictions of the OS and the whole setup but for test purposes and non critical applications it could work.

Lets assume that it's acceptable so I guess that a separate thread should be created in order to run the control code.
Has anyone done it before?

5

Support Questions / Re: How to stucture a program in C# for Modbus RTU communication

« on: October 26, 2018, 05:11:24 AM »

Archie,

The problem I have with BasicLevel is that I can't set scaling to "0.1" as Visual studio it doesn't accept "." as delimiter and it doesn't work propely when I put ",".

6

Support Questions / How to stucture a program in C# for Modbus RTU communication

« on: October 26, 2018, 02:40:29 AM »

Hi,

I want to read 3 Modbus registers from a level measuring device.
What I do now is to list all the available com ports and then after selecting the correct one I start reading and displaying the 3 registers by using BasicLabel controls.

It works but this is not how I want it to work.
Is it possible to establish Modbus communication and then start reading Modbus data?

So I use the following code:

Code: [Select]

private void MainForm_Load(object sender, EventArgs e)
        {
            //show list of valid com ports
            foreach (string s in System.IO.Ports.SerialPort.GetPortNames())
            {
                comboBox1.Items.Add(s);
            }
        }

        private void button1_Click(object sender, EventArgs e)
        {
            modbusRTUCom1.PortName = comboBox1.SelectedItem.ToString();
        }

        private void modbusRTUCom1_ConnectionEstablished(object sender, EventArgs e)
        {
            button1.Text = "Connected";
            Timer timerReadPLC = new Timer();
            timerReadPLC.Interval = 500;
            timerReadPLC.Tick += new EventHandler(timerReadPLC_Tick);
            timerReadPLC.Start();
        }

        void timerReadPLC_Tick(object sender, EventArgs e)
        {
                litersMod.Text = modbusRTUCom1.Read("30001").ToString();
                kilosMod.Text = modbusRTUCom1.Read("30003").ToString();
                int x = Int32.Parse(modbusRTUCom1.Read("30002")) / 10;
                levelMod.Text = x.ToString();
        }

Is it a proper way to make a program?

Also I don't really undestand what modbusRTUCom1.Subscribe and modbusRTUCom1.BeginRead methods do.

7

Support Questions / Manually select serial for port for Modbus RTU

« on: March 25, 2015, 12:35:23 PM »

In my application I don't to hardcode the serial port number into my code but I want to be able to select the port from a combobox and the start the connection.
So I have created a combobox and populate it with the available com ports. Then I added a button and as soon as I selected the appropriate com port I use it to read from the address I need and write the value to DigitalPanelMeter.
I need to press the button every time I want to read. Is it possible to poll the slave every 500ms as it's done the ModbusRTUCom driver is added in the designer?
Do I need to create an event to achieve this?
I'm not an expert in VB.NET (yet) so any help will be appreciated. Below is my code.

Private Sub MainForm_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        Dim ports As String() = SerialPort.GetPortNames()
        Dim port As String
        For Each port In ports
            ComboBox1.Items.Add(port)
        Next port
End Sub

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Dim ModbusDriverXR80CX As New ModbusRTUCom
        ModbusDriverXR80CX.PortName = ComboBox1.SelectedItem
        ModbusDriverXR80CX.BaudRate = 9600
        ModbusDriverXR80CX.StationAddress = 5
        DigitalPanelMeter1.Value = ModbusDriverXR80CX.Read("40257")
End Sub