Enabling distributed clocks

This chapter explains how to enable distributed clocks (DC) in the slave interface of the CX8110. To this end, the CX8110 is scanned in TwinCAT, and the slave interface and the lower master of the CX8110 are created.

Proceed as follows:

1. In the tree view on the left, click on EtherCAT slave.
Enabling distributed clocks 1:

2. Click on the EtherCAT Slave tab

3. Select the Enable Synchronization option.

You have successfully enabled distributed clocks (DC) if the variables DcToTcTimeOffset, DcTimeDiff and Dc State were created under InfoData. From now on you can measure the time difference between the master and slave clock with the variable DcToTcTimeOffset. You can determine when the CX8110 is synchronized by reading the value of the DcTimeDiff variable. A control configuration can be regarded as optimal with a task time of 1 ms and a DcTimeDiff of less than 10 ns. A DcTimeDiff of less than 100 ns is regarded as adequate.

In the next step you can configure the master of the CX8110.