Mapping vs. PLC library
Communication with an S7 Controller can be done in two ways. In the classic way, access to the controller and the data points to be read or written can be configured via the I/O device. For operating environments where there should be a somewhat more dynamic access, the PLC library Tc3_S7Comm is available for establishing the connection and for reading/writing data points. The following table shows both modes of communication in comparison.
| Mapping | PLC |
|---|---|---|
Changing connection parameters dynamically | no | yes |
Adding/Removing S7 data points dynamically | no | yes |
In the Samples chapter you will find examples of both communication types.