Profibus

"Station No." NumericUpDown control

The PROFIBUS station address set on the respective slave device can be set here.

"Set…" button

There are slave devices for which the station address cannot be set on the hardware, but only via the SetSlaveAddress service. The "Set…" button opens a dialog through which sending of a SetslaveAddress telegram can be triggered.

"Ident No." text box

Here, the Ident number from the GSD file is displayed.

"CfgData" text box

The current configuration data are derived from the attached modules or terminals. They are displayed bytewise in hexadecimal notation, as they are sent from the master device to the slave devices. The length of the configuration data in bytes is displayed in the text box on the right.

"Own PrmData" text box

The control element enables editing of the PROFIBUS-specific parameter data. They are displayed bytewise in hexadecimal notation, as they are sent from the master device to the slave devices. The size of the current parameter data in bytes is also displayed in the text box on the right. However, the parameter data can usually be set textually (PrmData (text)) or, for Beckhoff DP slave devices, partly via the "Beckhoff" tab.

Watchdog "Enable" check box

The "Enable" check box activates the DP watchdog. If a slave device does not receive a DP telegram during the watchdog time when the watchdog is enabled, it automatically leaves the data exchange. The minimum watchdog time to be set depends on the DP cycle time, and should be larger than the value calculated by the following formula: Estimated-Cycle-Time x 10.

"Time" text box

All Beckhoff slave devices, with the exception of the BK3000 and BK3100 devices, and third-party devices whose GSD file contains the entry "WD_Base_1ms_supp = 1" support a watchdog base time of 1 ms. If DP slave devices support a watchdog base time of 1 ms, a DP watchdog down to 2 ms can be set for their outputs, if they are particularly critical. However, the DP watchdog time should be at least twice the maximum of cycle time and estimated cycle time.

DPV1-Class 2

With the FC310x/EL6731, a DPV1 class 2 connection to a DPV1 slave device can be activated. This is useful, for example, if the DP slave device exchanges data with another master device, but TwinCAT should nevertheless address it acyclically. The "Watchdog" parameter can be used to set the connection monitoring time for the class 2 connection.

"Enable DPV1-C2" check box

If the "Enable DPV1-C2" check box is not checked, the "Disable Abort" and "Watchdog" control elements are grayed out. If the "Enable DPV1-C2" check box is checked, a DPV1 class 2 connection to a DPV1 slave device is activated, and the "Disable Abort" and "Watchdog" control elements can be used.

"Disable Abort" check box

"Watchdog" text box

The connection monitoring time for the class 2 connection can be entered in the "Watchdog" text box.

"Sync/Freeze enable" check box

If the master operates in DP/MC (equidistant) mode, slaves can be operated with Sync and Freeze.

"PrmStruct enable" check box

If the "PrmStruct enable" check box is checked, the interpretation of parameter data from an external GSD file as such parameter data is enabled.

DP Class 2

If a DP slave device is in data exchange with another master device but still needs to be acyclically addressed by TwinCAT, the "DP-Class 2" option "No Cyclic Connection" must be checked. If a DP slave device is in data exchange with another master device but its DP inputs or outputs are still to be read cyclically, you must select the "Read-Only" option under "DP-Class 2". If "Read-Only" is selected, the modules must be selected as for the cyclic connection, but they all appear in the TwinCAT system with input variables, regardless of whether they are input modules or output modules. "Read­Only" is only supported from firmware version 3.00.

"Disabled" option

TwinCAT should not acyclically address the DP slave device.

"Read-Only" option

The "Read-Only" option is not yet supported.

"No Cyclic Connection" option

Select this option if the DP slave device is to be acyclically addressed by TwinCAT while it is in data exchange with another master device.

Wait for DataExchange "Enable" check box

"Timeout" NumericUpDown control

"Publisher enable" check box

"Isochron enable" check box

If the "Isochron enable" check box is checked, the PROFIBUS runs isochronous with the clock telegram. This is relevant for Motion Control applications, for example.

"I/O-Reset Slave" button

This button can be used to terminate and immediately re-establish the cyclic data exchange to the DP slave when TwinCAT is started. This corresponds to an IO reset, but only for the one slave.