Tree view
A Profibus master and a Profibus slave are displayed as follows in the tree view:
In this example the slave was linked to the master. TwinCAT was then scanned for the master, and the master was added in TwinCAT together with the slave.
Number | Description |
|---|---|
1 | The device name of the master is shown in brackets. All Profibus slaves are added under the master. |
2 | Under the Profibus master, status messages are listed as input variables and output variables. The variables can be linked with the PLC and used for diagnostic purposes (e.g. error codes, counters, etc.). |
3 | Profibus slaves are added under the master, labelled as box and numbered consecutively. The device name appears in brackets after it. Each Profibus slave has its own input variables for diagnostic purposes, which indicate the state of the communication (DPState, ExtDiagFlag). |
4 | Further settings for the Profibus master or slave can be implemented under the tabs. Other tabs are displayed, depending on whether the master or slave is selected in the tree view. |
A Profibus slave and the corresponding tabs are shown as follows in the tree view:
Number | Description |
|---|---|
1 | Under the Profibus slave, status messages are listed as input variables. The variables can be linked with the PLC and used for diagnostic purposes. The inputs DpState and ExtDiagFlag are created for each slave box. In addition, process data for the data exchange are added under the slave. |
2 | All slaves are added under the master. This example shows the B3100 with connected Bus Terminals. All available terminals are displayed with their inputs and outputs. |
3 | Further settings for the Profibus slave can be implemented under the tabs. Other tabs are displayed, depending on whether the master or slave is selected in the tree view. |
When the PLC process image is read, the variables for status messages and the variables under the process data can be linked with the variables from the PLC program. Double-click on a variable name in the tree view to open the link dialog. The link variables are identified with a small arrow icon.
Further information about TwinCAT can be found in the TwinCAT documentation on the Beckhoff website:
www.beckhoff.de