Skip to Content

SiePortal

The integrated platform for your product selection, buying and support workflow - bringing together Industry Mall and Online Support.

SiePortalDeutsch

Search

Home
Support Support
{{(apiData.Support | filter:{'rank':1}:true)[0].title}} Support
- Menu temporary not available
- Menu temporary not available
- Menue temporary not available
- {{item.title}}

Products & Services
- Menu temporary not available
- Menue temporary not available
- {{item.title}}
Support Support
{{(apiData.Support | filter:{'rank':1}:true)[0].title}} Support
- Menu temporary not available
- Menue temporary not available
- {{item.title}}
MySiePortal MySiePortal
{{(apiData.MySiePortal | filter:{'rank':1}:true)[0].title}} MySiePortal
- Menu temporary not available
- Menue temporary not available
- {{item.title}}
Cart ({{apiData.CartCount}})

Navigation

read problem from vb net

Created by: nagy at: 5/10/2016 7:58 PM (8 Replies)

Rating (0)

Thanks 0

9 Entries

5/10/2016 7:58 PM	Rate (0)
nagy Posts: 8 Rating: (0)	Hello Guys, my goal is to read data to the PLC (next step will be to write) in the simplest way. After much research I wrote the code that I think is the most appropriate. The code is: Imports OPCSiemensDAAutomation Public Class Form1 Const itemCount = 2 Dim WithEvents opc_Server As OPCServer Dim opc_Groups As OPCGroups Dim WithEvents opc_Group As OPCGroup Dim clientHandles(itemCount) As Integer Dim opc_items(itemCount) As OPCItem Private Sub ConnectBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ConnectBtn.Click opc_Server = New OPCServer() If opc_Server Is Nothing Then MsgBox("Server not created", vbCritical, "") Exit Sub End If 'ServerObj = New OPCSiemensDAAutomation.OPCServer opc_Server.Connect("OPC.SimaticNet") If opc_Server Is Nothing Then MsgBox("OPC server connection failed", vbCritical, "") Exit Sub End If ConnectedLbl.Visible = True ConnectedLbl.Update() 'add the group opc_Groups = opc_Server.OPCGroups opc_Group = opc_Groups.Add("Group_1") opc_Group.IsActive = True 'create the items 'opc_items(0) = opc_Group.OPCItems.AddItem("S7:[S7 connection_1]DB4109,B16", clientHandles(0)) 'opc_items(1) = opc_Group.OPCItems.AddItem("S7:[S7 connection_1]DB4109,B17", clientHandles(1)) opc_items(0) = opc_Group.OPCItems.AddItem("S7:[S7 connection_1]DB4109,B16", 1) opc_items(1) = opc_Group.OPCItems.AddItem("S7:[S7 connection_1]DB4109,B17", 2) ReadTimer_Tick(sender, e) 'we can start reading End Sub Private Sub DisconnectBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles DisconnectBtn.Click ConnectedLbl.Visible = False ConnectedLbl.Update() If opc_Server Is Nothing Then 'safety Exit Sub End If opc_Server.OPCGroups.RemoveAll() 'free all the items and groups opc_Server.Disconnect() 'disconnect from the OPC Server opc_Server = Nothing End Sub Private Sub ReadTimer_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ReadTimer.Tick Dim i As Integer Dim ServerHandles As Array = Array.CreateInstance(GetType(Int32), itemCount) 'item ID (server side) Dim Values As Array = Array.CreateInstance(GetType(Object), itemCount) 'return values Dim Errors As Array = Array.CreateInstance(GetType(Int32), itemCount) Dim Qual As Array = Array.CreateInstance(GetType(Object), itemCount) Dim TimeValue As Array = Array.CreateInstance(GetType(Object), itemCount) Try ReadTimer.Enabled() = False If opc_Server Is Nothing Then 'safety Exit Sub End If If Not (opc_Server.ServerState = OPCServerState.OPCRunning) Then 'safety Exit Sub End If 'set up which items to be read Try For i = 0 To itemCount - 1 ServerHandles(i) = opc_items(i).ServerHandle Next i Catch ex As Exception MessageBox.Show("Error") ReadTimer.Enabled = False End Try Try opc_Group.SyncRead(OPCDataSource.OPCCache, 2, ServerHandles, Values, Errors, Qual, TimeValue) Catch ex As Exception MessageBox.Show("Sync read failed") ReadTimer.Enabled = False End Try Label2.Text = Values(1) Label2.Update() Finally ReadTimer.Enabled() = True End Try End Sub End Class I have a proble as shown i the attached pic. Can You help me please? Thank you Daniel
nagy Posts: 8 Rating: (0)
Suggestion To thank Quote Answer

5/10/2016 9:10 PM	Rate (0)
vipz Gold Member Joined: 9/2/2012 Last visit: 3/14/2025 Posts: 711 Rating: (30)	Hi, attachment missing ?
	With Best Regards VIPZ
Suggestion To thank Quote Answer

5/10/2016 10:03 PM	Rate (0)
nagy Posts: 8 Rating: (0)	I'm sorry Attachment error.png (190 Downloads)
nagy Posts: 8 Rating: (0)
Suggestion To thank Quote Answer

5/11/2016 10:08 AM	Rate (0)
Duris_I Diamond Expert Joined: 4/28/2015 Last visit: 2/24/2025 Posts: 10832 Rating: (836)	Hello, simply debug that Values after RUN step by step and look inside if array isn't null, this can be your problem - Values(1).
	With best regards... Ivan Duris Flight: OMICO
Suggestion To thank Quote Answer

5/11/2016 5:12 PM	Rate (0)
nagy Posts: 8 Rating: (0)	Thanks for answer, tomorrow I'll try in this way. Anyway today I saw in "S7 Connection Diagnostic" that connection state is "NOT USED". I don't understand the reason, I don't know if I did some mistakes in opc configuration I don't think so because I checked more times the configuration. Is this the problem in your opinion? Attachment s7 diagnostic.png (151 Downloads)
nagy Posts: 8 Rating: (0)
Suggestion To thank Quote Answer

5/17/2016 12:59 PM	Rate (0)
nagy Posts: 8 Rating: (0)	After many test, I think the problem is that my opcserver doesn't connect. I still have "State not Used" in S7connection diagnostic. Do you have some idea? I use S7300 and Win7Pro
nagy Posts: 8 Rating: (0)
Suggestion To thank Quote Answer

5/17/2016 1:22 PM	Rate (0)
Duris_I Diamond Expert Joined: 4/28/2015 Last visit: 2/24/2025 Posts: 10832 Rating: (836)	Hello, what can I recommend to you... Simply debug all Button events with needed objects living, also some statuses in Global memory area (if exists and used in another areas), there is probably something on begining of initialization of basic objects. Give info.
	Last edited by: Duris_I at: 5/17/2016 2:42:43 PM With best regards... Ivan Duris Flight: OMICO
Suggestion To thank Quote Answer

5/17/2016 3:52 PM	Rate (0)
nagy Posts: 8 Rating: (0)	I tried with Debugger and it seems everythings ok till program run the command line which generates the error that you see in previous pic. In this command line, by using debugger, I can see that values are 'nothing'. Which info Can I give You? Sorry but I'm just learning this kind of communication and I don't have enough experience. If you need I can attach my files
nagy Posts: 8 Rating: (0)	Last edited by: nagy at: 5/17/2016 3:53:09 PM
Suggestion To thank Quote Answer

5/18/2016 7:58 AM	Rate (0)
Duris_I Diamond Expert Joined: 4/28/2015 Last visit: 2/24/2025 Posts: 10832 Rating: (836)	Hello, I was working in VB long time ago, also cant test OPC, but what I've discovered also is, look at your code again, code lines before that label2 has Catch Exceptions, but if that Exception occur - probably better will be exit sub, am I right? You simply continue after Exception to that label2.text even you'll have nothing in that array, so I see so much other problems in your code. Next recommendation can be look for basic configuration of OPC for first, check functionality of OPC Server correctly runing??? and then connect via your SW to it. Sry I'm working C/C++ but also my ask is due that label2.text, is there problem to write this: label2.text="" label2.text=label2.text+Values(1) Pls look, my syntax can be simply wrong in VB but I think better will be init with null string that label2 and then add some value to it everytime. Try my recommendations and give info, but for first check OPC basic functionality, configuration, look to documentation for OPC. Update: also question, why you need from Values index 1 - value? I don't know internal structure of that.
	Last edited by: Duris_I at: 5/18/2016 10:33:52 AM With best regards... Ivan Duris Flight: OMICO
Suggestion To thank Quote Answer

|

Share this page:

Share this page on...

Follow us on