Configuration
4.10 Data points
CP 1243-1
82
Operating Instructions, 04/2017, C79000-G8976-C365-03
4.10
Data points
4.10.1
Data point configuration
Data point-related communication with the CPU
No program blocks need to be programmed for telecontrol modules with data point
configuration to transfer user data between the station and communications partner.
The data areas in the memory of the CPU intended for communication with the
communications partner are configured data point-related on the module. Each data point is
linked to a PLC tag or the tag of a data block.
Requirement: Created PLC tags and/or data blocks (DBs)
PLC tags or DBs must first be created in the CPU program to allow configuration of the data
points.
The PLC tags for data point configuration can be created in the standard tag table or in a
user-defined tag table. All PLC tags intended to be used for data point configuration must
have the attribute "Visible in HMI".
Address areas of the PLC tags are input, output or bit memory areas on the CPU.
Note
Number of PLC tags
Remember the maximum possible number of PLC tags the can be used for data point
configuration in the section Configuration limits and performance data (Page 15).
The formats and S7 data types of the PLC tags that are compatible with the protocol-specific
data point types of the module can be found in the section Datapoint types (Page 89).
Access to the memory areas of the CPU
The values of the PLC tags or DBs referenced by the data points are read and transferred to
the communications partner by the module.
Data received from the communications partner is written by the module to the CPU via the
PLC tags or DBs.
Configuring the data points and messages in STEP 7
You configure the data points in STEP 7 in the data point and message editor. You can find
this using the project tree:
Project > directory of the relevant station > Local modules > CP