pkingsbury
Member
Hello all,
I am beginning to write an application which obtains PLC data via the DDE interface in RSLinx Classic.
Previously I had configured an Excel spreadsheet to obtain the data, but due to a number of consistent application failures (application crashing after X hours, data not being read without twiddling with the spreadsheet, etc) I decided to write a more reliable and less crash-prone C++ application.
In the spreadsheet I had accessed the RSLinx DDE interface using "RSLINX" as the 'application', and the shortcuts I'd defined inside RSLinx Classic as the 'topic'. Despite the problems I mentioned above, this works.
I tried using these values for the application and topic inside my C++ application, and I consistently get the error 'DMLERR_NO_CONV_ESTABLISHED', which evaluates to the description "A client's attempt to establish a conversation has failed".
I have only begun scratching the surface of DDE via C++, and have been using a tutorial (here) as a starting point for reading my PLC data (adapting it to read through RSLinx rather than from a local application).
I am unsure how to proceed, so any help would be appreciated!
Best regards,
- Peter
I am beginning to write an application which obtains PLC data via the DDE interface in RSLinx Classic.
Previously I had configured an Excel spreadsheet to obtain the data, but due to a number of consistent application failures (application crashing after X hours, data not being read without twiddling with the spreadsheet, etc) I decided to write a more reliable and less crash-prone C++ application.
In the spreadsheet I had accessed the RSLinx DDE interface using "RSLINX" as the 'application', and the shortcuts I'd defined inside RSLinx Classic as the 'topic'. Despite the problems I mentioned above, this works.
I tried using these values for the application and topic inside my C++ application, and I consistently get the error 'DMLERR_NO_CONV_ESTABLISHED', which evaluates to the description "A client's attempt to establish a conversation has failed".
I have only begun scratching the surface of DDE via C++, and have been using a tutorial (here) as a starting point for reading my PLC data (adapting it to read through RSLinx rather than from a local application).
I am unsure how to proceed, so any help would be appreciated!
Best regards,
- Peter