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Read ad Write multiple values
20 Feb 2024 17:41 #12566
by support
Replied by support on topic Read ad Write multiple values
Examples for OPC client and subscriber development in Python are now on GitHub: github.com/OPCLabs/Examples-QuickOPC-Python .
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21 Nov 2023 13:35 #12397
by support
Replied by support on topic Read ad Write multiple values
Note: QuickOPC now supports Python in much better way, cleaner syntax, and public packages (pypi.org/project/opclabs-quickopc/) on
Python Package Index
. See
What's new in QuickOPC 2023.2
for more information. And, over 270 examples are available in the User's Guide!
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20 Aug 2019 06:11 #7634
by support
Replied by support on topic Read ad Write multiple values
Hello.
It looks like that we have worked on similar issue in Python before. The results array is weird - but it still can be processed. Please see www.opclabs.com/forum/general-issues-building/2466-quickopc-in-python#6436 , and attempt to extract the results (roughly) like this:
Best regards
It looks like that we have worked on similar issue in Python before. The results array is weird - but it still can be processed. Please see www.opclabs.com/forum/general-issues-building/2466-quickopc-in-python#6436 , and attempt to extract the results (roughly) like this:
Result1 = win32com.client.Dispatch(val[0][0])
Result2 = win32com.client.Dispatch(val[0][1])
Result3 = win32com.client.Dispatch(val[0][2])
Vtq1 = Result1.Vtq
Vtq2 = Result2.Vtq
Vtq3 = Result3.VtqPlease Log in or Create an account to join the conversation.
- Jesus Rodriguez
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17 Aug 2019 20:03 #7632
by Jesus Rodriguez
Replied by Jesus Rodriguez on topic Read ad Write multiple values
Hi, thanks for your reply, I just tried to run it in python. This is what I got:
import win32com.client
ReadItemArguments1 = win32com.client.Dispatch("OpcLabs.EasyOpc.DataAccess.OperationModel.DAReadItemArguments")
ReadItemArguments1.ServerDescriptor.ServerClass = "OPCLabs.KitServer.2"
ReadItemArguments1.ItemDescriptor.ItemID = "Demo.Single"
ReadItemArguments2 = win32com.client.Dispatch("OpcLabs.EasyOpc.DataAccess.OperationModel.DAReadItemArguments")
ReadItemArguments2.ServerDescriptor.ServerClass = "OPCLabs.KitServer.2"
ReadItemArguments2.ItemDescriptor.ItemID = "Demo.Single"
arguments = [ReadItemArguments1, ReadItemArguments2]
client = win32com.client.Dispatch('OpcLabs.EasyOpc.DataAccess.EasyDAClient')
results = client.ReadMultipleItemValues(arguments)
There is no error at this point but still I think is not correct since I cannot get the values.
Thank you for your help
import win32com.client
ReadItemArguments1 = win32com.client.Dispatch("OpcLabs.EasyOpc.DataAccess.OperationModel.DAReadItemArguments")
ReadItemArguments1.ServerDescriptor.ServerClass = "OPCLabs.KitServer.2"
ReadItemArguments1.ItemDescriptor.ItemID = "Demo.Single"
ReadItemArguments2 = win32com.client.Dispatch("OpcLabs.EasyOpc.DataAccess.OperationModel.DAReadItemArguments")
ReadItemArguments2.ServerDescriptor.ServerClass = "OPCLabs.KitServer.2"
ReadItemArguments2.ItemDescriptor.ItemID = "Demo.Single"
arguments = [ReadItemArguments1, ReadItemArguments2]
client = win32com.client.Dispatch('OpcLabs.EasyOpc.DataAccess.EasyDAClient')
results = client.ReadMultipleItemValues(arguments)
There is no error at this point but still I think is not correct since I cannot get the values.
Thank you for your help
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14 Aug 2019 07:51 #7621
by support
Replied by support on topic Read ad Write multiple values
There are ReadMultipleItems and ReadMultipleItemValues methods for this purpose. See e.g. opclabs.doc-that.com/files/onlinedocs/QuickOpc/Latest/User%2...ding%20just%20the%20value.html .
I do not have Python example at hand. hopefully you can derive it from code given in other languages. If you run into an issue, let me know here. Here is a VBScript example for ReadMultipleItemValues:
Best regards
I do not have Python example at hand. hopefully you can derive it from code given in other languages. If you run into an issue, let me know here. Here is a VBScript example for ReadMultipleItemValues:
Rem This example shows how to read values of 4 items at once, and display them.
Option Explicit
Dim ReadItemArguments1: Set ReadItemArguments1 = CreateObject("OpcLabs.EasyOpc.DataAccess.OperationModel.DAReadItemArguments")
ReadItemArguments1.ServerDescriptor.ServerClass = "OPCLabs.KitServer.2"
ReadItemArguments1.ItemDescriptor.ItemID = "Simulation.Random"
Dim ReadItemArguments2: Set ReadItemArguments2 = CreateObject("OpcLabs.EasyOpc.DataAccess.OperationModel.DAReadItemArguments")
ReadItemArguments2.ServerDescriptor.ServerClass = "OPCLabs.KitServer.2"
ReadItemArguments2.ItemDescriptor.ItemID = "Trends.Ramp (1 min)"
Dim ReadItemArguments3: Set ReadItemArguments3 = CreateObject("OpcLabs.EasyOpc.DataAccess.OperationModel.DAReadItemArguments")
ReadItemArguments3.ServerDescriptor.ServerClass = "OPCLabs.KitServer.2"
ReadItemArguments3.ItemDescriptor.ItemID = "Trends.Sine (1 min)"
Dim ReadItemArguments4: Set ReadItemArguments4 = CreateObject("OpcLabs.EasyOpc.DataAccess.OperationModel.DAReadItemArguments")
ReadItemArguments4.ServerDescriptor.ServerClass = "OPCLabs.KitServer.2"
ReadItemArguments4.ItemDescriptor.ItemID = "Simulation.Register_I4"
Dim arguments(3)
Set arguments(0) = ReadItemArguments1
Set arguments(1) = ReadItemArguments2
Set arguments(2) = ReadItemArguments3
Set arguments(3) = ReadItemArguments4
Dim Client: Set Client = CreateObject("OpcLabs.EasyOpc.DataAccess.EasyDAClient")
Dim results: results = Client.ReadMultipleItemValues(arguments)
Dim i: For i = LBound(results) To UBound(results)
WScript.Echo "results(" & i & ").Value: " & results(i).Value
NextBest regards
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13 Aug 2019 05:36 #7620
by admin
Replied by admin on topic Read ad Write multiple values
Please be [patient. Will reply later this week, as soon as possible. We have a vacation period.
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- Jesus Rodriguez
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12 Aug 2019 18:26 #7619
by Jesus Rodriguez
Read ad Write multiple values was created by Jesus Rodriguez
Hi
I have the following code to read and write:
import win32com.client
client = win32com.client.Dispatch('OpcLabs.EasyOpc.DataAccess.EasyDAClient')
value = client.ReadItemValue('', 'CoDeSys.OPC.02', '.Inputs[9]')
client.WriteItemValue('', 'CoDeSys.OPC.02', '.Inputs[9]', 7)
They work well but I would like to know how to read and write multiple values in just one function. Is there any function already doing this?
Thank you.
I have the following code to read and write:
import win32com.client
client = win32com.client.Dispatch('OpcLabs.EasyOpc.DataAccess.EasyDAClient')
value = client.ReadItemValue('', 'CoDeSys.OPC.02', '.Inputs[9]')
client.WriteItemValue('', 'CoDeSys.OPC.02', '.Inputs[9]', 7)
They work well but I would like to know how to read and write multiple values in just one function. Is there any function already doing this?
Thank you.
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