Appendices
28.1
Precautions for DOP use
Precautions for DOP use
Introduction
List of precautions
The list below is not exhaustive, however, it does group together the errors most frequently encountered whilst installing DOP functions in an application. l l l l l l l l l
Do not forget to initialize the Time-out parameter (%MWi+2) before starting the
Operator Dialogue function. For the ASK_MSG or ASK_VALUE functions, the value has to be 0.
If you use the same word to save each function’s report, you must then test the activity bit (%MWi:X0) at value 0 before starting another function.
Synchronize the start of the different Built-in DOP functions in order that the CCX
17 console command queue does not become full.
Remember to correctly calculate the size of the %KWi internal constants for displaying the data to be sent.
Do not hesitate to allow a margin for error when allocating the data to be sent
(%KWi:n). In fact, if you need to modify the text name, there will be no overlap between the different %KWi:n references.
The maximum size for the Built-in DOP functions is 47 words.
Warning, it is impossible to create a Built-in DOP function in line modification mode, if the application located in the PLC does not already contain a copy of this function.
During power outage or communication loss, the application has to reset the CCX
17 in a coherent state (assigning buttons and messages to the screen).
Canceling modifications or deleting a rung or phrase (List or Text) does not cancel initialization of the %KWi variables.
330
TLX DS 37 PL7 xxE
