Built-in DOP functions
Parameters field: Data to be sent
Introduction
Locating items within the PLC application
Data to be sent is individual to each type of MMI function.
The data can be found either in the PLC application, or in the CCX 17 when it has its own application.
In the case where data is to be found in the PLC application, it can be sent from: l l a table of internal words (%MW), a table of internal constants (%KW).
The table below shows the structure of data sent in this way.
Role Word number
1
2
3
4, 5, ...
Contains a contains a marker for value 16#CC17, and has a double role: l it allows the Help screen to identify a correct message and to redisplay the values on the entry screen in order to help modify or display default values.
l it allows the function being carried out to check that the table received does actually contain a message for a CCX 17. In fact, it is possible to call an
Integrated DOP function in a program without going via the Help/Control screens.
In the case of an unmarked message, the function can immediately return an error back to the application without sending unreliable data to the console.
Contains the command number.
Contains the length of data to be sent.
Contains the data to be sent.
Note: For reasons of efficiency, the <Data to be sent> parameter can be programmed using %KWi constants. In this way the software automatically initializes this data field with adequate values.
Selecting %MW bars access to different fields in the entry help box for integrated
DOP functions. It is then necessary to establish, either manually or by program, the contents of the data to be sent (see PL7 MMI 17 software documentation).
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TLX DS 37 PL7 xxE
Location in a
CCX 17 with application
Built-in DOP functions
When data is in a CCX 17, the data to be sent is limited to DOP function execution commands.
This data can be sent from the PLC application: l l from a table of internal words (%MW), from a table of internal constants (%KW), l directly using an immediate integer value.
The table above shows data structure when using a table.
Role
1
2
Word number
Contains a command number
Contains the data to be sent to the console.
TLX DS 37 PL7 xxE
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