Creating a virtual slave

Up to three virtual slaves can be configured for the EK3100 Bus Coupler. Virtual slaves can be used to increase the transfer rate beyond the standard PROFIBUS rate of 244 bytes. The maximum process data size is 240 byte inputs and 240 byte outputs per slave.

In order to be able to use virtual slaves, the EtherCAT Terminals must be successive, and all EtherCAT Terminals must occur in the slaves. In addition, it is important that a slave contains both input and output terminals.

By default only the first slave is activated. The virtual slaves are enabled in the configuration via the parameter data. The parameter data and the CtrlStatus DWORD only have the full functionality for the first slave.

The addressing is fixed and starts with the address, which the first slave uses via an address selection switch. If the address is set to 11, the following addresses are 12, 13 and 14 if all 4 slaves are active.

Example of a hardware configuration with a slave.

EtherCAT device, actual hardware configuration

EK3100

CtrlStatus

EL1008

EL2008

EL3062

EK1110

EK1100

EL2008

EL1008

EL3154

EL9011

Distribution of the EtherCAT device in TwinCAT over two slaves.

Slave 1

Slave 2 (virtual slave)

EK3100

CtrlStatus

EL1008

EL2008

EL3062

EK1110

EK3100

CtrlStatus

EK1100

EL2008

EL1008

EL3154

PROFIBUS address: 11

PROFIBUS address: 12. The non-visible EL9011 is omitted.

Requirements

Create virtual slaves as follows:

1. In the tree view on the left, double-click on Box 1 (GSD box) (EK3100).
Creating a virtual slave 1:
2. Click on the tab PrmData (Text).
3. Double-click on Enabled DP Slaves and select the number of virtual slaves.
Creating a virtual slave 2:
4. Add a further EK3100 Bus Coupler under the existing EK3100 Bus Coupler. This Bus Coupler is the virtual slave.
5. Click on the Profibus tab and enter the PROFIBUS address "12" under Station No.
Add all EtherCAT Terminals after the EK3100 Bus Coupler and the virtual slave. Use the above table for guidance.
Creating a virtual slave 3: