dOPC FAQ's

How can I debug into the dOPC source code?
The easiest way to debug into the dOPC source is to add the following string to the "Search Path" of your Project (Project Options-\> Building-\> Delphi Compiler): $(dOPC)\core;$(dOPC)\ua;$(dOPC)\xml;$(dOPC)\com;$(dOPC)\dialogs;$(dOPC)\ua\security Another way to debug into the dOPC source is to set the path to the dOPC source in the Delphi/C++ IDE. To set the path you have to do the following steps: Start Delphi/RAD Studio IDE Open menu "Tools/Options/Language/Delph/Library" Now add the $dOPC... folders above in the "Library path" section. You have to do step 3 for every platform you want to debug. Please note: Debugging will only work if you have the registered (with source code) dOPC Client Toolkit version installed in a writable folder. If this is not the case, please uninstall the toolkit via the Windows Control Panel and re-install it into a writable folder.

How can I debug into the dOPC source code?

The easiest way to debug into the dOPC source is to add the following string to the "Search Path" of your Project (Project Options-\> Building-\> Delphi Compiler):
$(dOPC)\core;$(dOPC)\ua;$(dOPC)\xml;$(dOPC)\com;$(dOPC)\dialogs;$(dOPC)\ua\security

Another way to debug into the dOPC source is to set the path to the dOPC source in the Delphi/C++ IDE. To set the path you have to do the following steps:

Start Delphi/RAD Studio IDE
Open menu "Tools/Options/Language/Delph/Library"
Now add the $dOPC... folders above in the "Library path" section.
You have to do step 3 for every platform you want to debug.

Please note: Debugging will only work if you have the registered (with source code) dOPC Client Toolkit version installed in a writable folder. If this is not the case, please uninstall the toolkit via the Windows Control Panel and re-install it into a writable folder.

I am not able to establish a connection to a OPC UA server
The dOPC UA client component implements the fastest OPC UA protocol, the OPC UA Binary (opc.tcp://...). This protocol is based on TCP/IP. If you get a common socket error such as "Connection refused" or "Time out", you must first check your network configuration, firewall and security settings. If your general settings are ok, please read the OPC UA & Security section.

I am not able to establish a connection to a classic OPC server
Please look at section "dOPC and DCOM"

How can I create 64 bit OPC classic client applications
Very important: To run OPC COM 64-bit client programs you have first to download and install the 64-bit OPC Core Components 3.00 Redistributable (x64) from the OPC Foundation. (a free registration is required) https://www.opcfoundation.org Also you have to recompile the dOPC Client Tookit. Please look to section below: "How can I create a dOPC applications for other platforms" That's normally all you have to do. Now you can create a 64 bit dOPC application. For further information about 64 bit application development look at your Delphi help file. Please note: Currently it is not possible to create 64 bit application for C++ Builder. Attention: If you want to use the TdOPCDAClient component under 64 bit Windows and you have Delphi 11 or a newer version, you have to compile your program with the following compiler directive {$HIGHENTROPYVA OFF}). For more information please refer to https://docwiki.embarcadero.com/RADStudio/Alexandria/en/Support_high-entropy_64-bit_ASLR

How can I create 64 bit OPC classic client applications

Very important: To run OPC COM 64-bit client programs you have first to download and install the 64-bit OPC Core Components 3.00 Redistributable (x64) from the OPC Foundation. (a free registration is required)

https://www.opcfoundation.org

Also you have to recompile the dOPC Client Tookit. Please look to section below: "How can I create a dOPC applications for other platforms"
That's normally all you have to do. Now you can create a 64 bit dOPC application. For further information about 64 bit application development look at your Delphi help file.
Please note: Currently it is not possible to create 64 bit application for C++ Builder.

Attention:
If you want to use the TdOPCDAClient component under 64 bit Windows and you have Delphi 11 or a newer version, you have to compile your program with the following compiler directive {$HIGHENTROPYVA OFF}). For more information please refer to

https://docwiki.embarcadero.com/RADStudio/Alexandria/en/Support_high-entropy_64-bit_ASLR

Is it possible to connect to remote OPC COM servers with dOPC?
dOPC supports connections to remote OPC servers, but you need to configure DCOM on both client and server beforehand. For further information please look at section: dOPC and DCOM

Which OPC components do I have to distribute with my client program developed with dOPC?
OPC XML DA clients: If you use OPC XML DA as communication layer, you only need to distribute your EXE file. OPC UA clients: If you are using OPC UA and our default native security setting (SecurityLib := uaSNative) then all you need to do is distribute your EXE file, nothing more :-) If you are using security or authentication and the SecurityLib property is set to uaSOpenSSL, you must distribute the following OpenSSL library files with your EXE file: ssleay32.dll and libeay32.dll You can find the versions we used in the dOPC installation folder in the path "tools" or "tools\win64" for the 64 bit versions or at https://indy.fulgan.com/SSL/. OPC Classic COM based clients: If you run the program you developed on the same PC the OPC server is running on (local access), you also only need to distribute your EXE file, because usually all required OPC components have been installed by the OPC server. If your client program does not run on the same PC the OPC COM server is running on (remote access), you have to configure DCOM and you need to install the OPC Core Components. You can download the "OPC Core Components" installation program at the OPC Foundation (Resources/Sample and Tools/Classic). The direct link is https://opcfoundation.org/developer-tools/samples-and-tools-classic.

Which OPC components do I have to distribute with my client program developed with dOPC?

OPC XML DA clients:
If you use OPC XML DA as communication layer, you only need to distribute your EXE file.

OPC UA clients:
If you are using OPC UA and our default native security setting (SecurityLib := uaSNative) then all you need to do is distribute your EXE file, nothing more :-)
If you are using security or authentication and the SecurityLib property is set to uaSOpenSSL, you must distribute the following OpenSSL library files with your EXE file: ssleay32.dll and libeay32.dll
You can find the versions we used in the dOPC installation folder in the path "tools" or "tools\win64" for the 64 bit versions or at https://indy.fulgan.com/SSL/.

OPC Classic COM based clients:
If you run the program you developed on the same PC the OPC server is running on (local access), you also only need to distribute your EXE file, because usually all required OPC components have been installed by the OPC server.

If your client program does not run on the same PC the OPC COM server is running on (remote access), you have to configure DCOM and you need to install the OPC Core Components. You can download the "OPC Core Components" installation program at the

OPC Foundation (Resources/Sample and Tools/Classic). The direct link is

https://opcfoundation.org/developer-tools/samples-and-tools-classic.

Do I have to purchase any runtime licenses when I distribute my program developed with dOPC?
No, the dOPC Client Toolkit is licensed per developer and includes an unlimited runtime license (royalty-free runtime distribution). See also licence agreement

How can I create certificates for my OPC UA client program
The easiest way to create a certificate for your OPC UA program is to click on the "..." of the SecurityKeypair property of the TdOPCUAClient class in the Object Inspector of the IDE. This will open a dialog where you can press the "Create" button. You can also use the following link to find examples of how to create certificates for your OPC UA client program: click here

Is it possible to call OPC UA services with the TdOPCDAClient component?
Yes, the TdOPCDAClient component uses internally the TdOPCUAClient component. How to do it please: click here

How can I add a OPC UA NodeId to a dOPC group.
How to do it please: click here

How can I recompile the dOPC Client Toolkit
If you want to recompile the dOPC Client Toolkit, because e.g if the dOPC installation says that you don't have the right compiler version, then you have to do following steps. 1. Install the dOPC Client Toolkit on your computer to a writeable folder. 2. Open Delphi IDE 3. Now open packages file dOPCP.dproj from the "..\source\package" folder. 4. In the project Manager make a right click on dOPC.bpl and "Build" and "Install" the toolkit. 5. That's normally all, now it should work with your Delphi compiler version. Please note: This procedure works only with the registered source code version of dOPC. Also it is very important to install dOPC to a writeable folder elsewhere you can't compile the toolkit. If you have installed the toolkit in a none writeable folder, please use the Windows Control Panel to remove the toolkit and install it again into a writeable folder.

How can I recompile the dOPC Client Toolkit

If you want to recompile the dOPC Client Toolkit, because e.g if the dOPC installation says that you don't have the right compiler version, then you have to do following steps.
1. Install the dOPC Client Toolkit on your computer to a writeable folder.
2. Open Delphi IDE
3. Now open packages file dOPCP.dproj from the "..\source\package" folder.
4. In the project Manager make a right click on dOPC.bpl and "Build" and "Install" the toolkit.
5. That's normally all, now it should work with your Delphi compiler version.

Please note:
This procedure works only with the registered source code version of dOPC. Also it is very important to install dOPC to a writeable folder elsewhere you can't compile the toolkit. If you have installed the toolkit in a none writeable folder, please use the Windows Control Panel to remove the toolkit and install it again into a writeable folder.

How can I install the dOPC Client Toolkit manually.
If you want to compile the dOPC Client Toolkit on a new released Delphi version, which is not listed in dOPC installation, then you have to do following steps: 1. Install the dOPC Client Toolkit on your computer to a writeable folder. 2. Open Delphi IDE 3. Open in Delphi menu Tools->Options Tab: Environment Variables 4. Under "User System Overrides" add following items with button "New". Variable name Variable Value Example dOPCRoot dOPC Installation folder c:\dopc dOPC Folder to the source c:\dopc\source dOPCLib Delphi Package Version 280 (Delphi 11.1 Alexandria) 5. Now open packages file dOPCP.dproj from the "..\source\package" folder. 6. In the Delphi project manager make a right click on dOPC.bpl and "Build" and "Install" the toolkit. 7. That's normally all, now dOPC should work with the new Delphi version. Please note: This procedure works only with the registered source code version of dOPC. Also it is very important to install dOPC to a writeable folder elsewhere you can't compile the toolkit. If you have installed the toolkit in a none writeable folder, please use the Windows Control Panel to remove the toolkit and install it again into a writeable folder.

How can I install the dOPC Client Toolkit manually.

If you want to compile the dOPC Client Toolkit on a new released Delphi version, which is not listed in dOPC installation, then you have to do following steps:
1. Install the dOPC Client Toolkit on your computer to a writeable folder.
2. Open Delphi IDE
3. Open in Delphi menu Tools->Options Tab: Environment Variables
4. Under "User System Overrides" add following items with button "New".
Variable name Variable Value Example
dOPCRoot dOPC Installation folder c:\dopc
dOPC Folder to the source c:\dopc\source
dOPCLib Delphi Package Version 280 (Delphi 11.1 Alexandria)
5. Now open packages file dOPCP.dproj from the "..\source\package" folder.
6. In the Delphi project manager make a right click on dOPC.bpl and "Build" and "Install" the toolkit.
7. That's normally all, now dOPC should work with the new Delphi version.

Please note:
This procedure works only with the registered source code version of dOPC. Also it is very important to install dOPC to a writeable folder elsewhere you can't compile the toolkit. If you have installed the toolkit in a none writeable folder, please use the Windows Control Panel to remove the toolkit and install it again into a writeable folder.

How can I create a dOPC application for other platforms (e.g. Android and iOS)
Attention: Following description will only work if you have the installed the registered dOPC Client Toolkit version in a writeable folder. If not please uninstall the toolkit from the Windows control panel and install it again to a writeable folder. If you want to create dOPC applications for other platforms than Windows you have first to recompile the dOPC Client Toolkit. In order to do this please carry out the following steps: 1. Close your Delphi or C++ IDE and start program dCompile.exe You will find this program by default in the dOPC installation folder under: "..\tools\dcompile". 2. Open script file "dOPCCompileAll.cms" With the help of this script the dOPC Client Toolkit will be complied for following platforms: Windows 32 bit, Windows 64 Bit, Android, Mac OS and iOS In program "dcompile" click in main menu: "File->Load" to open the script file. You will find the script file in the dOPC installation folder under: "..\tools\dcompile". Press button "Run Script" The program should return with "building succesfully :-)" Now you can open the Delphi or C++ Builder IDE. For further information about multi platform developing please look to the Delphi or C++ Builder documentations. You will find multi platform OPC client programs (e.g. the dOPC Mobile Explorer) at: http://www.kassl.de/opc/download.shtml For Android, iOS and MAC OS it is only possible to create OPC UA and XML DA client programs. If you want to use OPC XML DA and your OPC server does not support OPC XML DA you can use our dOPC XGate to enlarge any classic OPC server with an OPC XML-DA interface. You will find dOPC XGate as trial version under the "tools" folder, or you can download the newest version at: http://www.kassl.de/opc/opc-server-gateway.shtml Attention: If you want to use the TdOPCDAClient component under 64 bit Windows and you have Delphi 11 or a newer version, you have to compile your program with the following compiler directive {$HIGHENTROPYVA OFF}). For more information please refer to https://docwiki.embarcadero.com/RADStudio/Alexandria/en/Support_high-entropy_64-bit_ASLR

How can I create a dOPC application for other platforms (e.g. Android and iOS)

Attention:
Following description will only work if you have the installed the registered dOPC Client Toolkit version in a writeable folder. If not please uninstall the toolkit from the Windows control panel and install it again to a writeable folder.

If you want to create dOPC applications for other platforms than Windows you have first to recompile the dOPC Client Toolkit. In order to do this please carry out the following steps:

1. Close your Delphi or C++ IDE and start program dCompile.exe
You will find this program by default in the dOPC installation folder under: "..\tools\dcompile".

2. Open script file "dOPCCompileAll.cms"
With the help of this script the dOPC Client Toolkit will be complied for following platforms:
Windows 32 bit, Windows 64 Bit, Android, Mac OS and iOS
In program "dcompile" click in main menu: "File->Load" to open the script file.
You will find the script file in the dOPC installation folder under: "..\tools\dcompile".
Press button "Run Script"
The program should return with "building succesfully :-)"

Now you can open the Delphi or C++ Builder IDE. For further information about multi platform developing please look to the Delphi or C++ Builder documentations.

You will find multi platform OPC client programs (e.g. the dOPC Mobile Explorer) at:

http://www.kassl.de/opc/download.shtml

For Android, iOS and MAC OS it is only possible to create OPC UA and XML DA client programs.

If you want to use OPC XML DA and your OPC server does not support OPC XML DA you can use our dOPC XGate to enlarge any classic OPC server with an OPC XML-DA interface. You will find dOPC XGate as trial version under the "tools" folder, or you can download the newest version at:

http://www.kassl.de/opc/opc-server-gateway.shtml
Attention:
If you want to use the TdOPCDAClient component under 64 bit Windows and you have Delphi 11 or a newer version, you have to compile your program with the following compiler directive {$HIGHENTROPYVA OFF}). For more information please refer to

https://docwiki.embarcadero.com/RADStudio/Alexandria/en/Support_high-entropy_64-bit_ASLR

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