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7.4
Synchronization
Ezi-IO EtherCAT DA provides the following synchronization modes.
Figure 7-7. Types of EtherCAT Synchronization
Free Run
7.4.1
The I/O module operates without being synchronized with the master. In Free Run mode, the master and I/O
module operate in their own cycles independently.
SM Event
7.4.2
The I/O module operates synchronously with the SyncManager (SM) Event of EtherCAT communication.
SM Event occurs when an EtherCAT Frame is received by the module, and each SM Event synchronized module
has a range of jitter in µs or less.
DC Sync Event
7.4.3
The I/O module operates synchronously with the Sync-Interrupt generated according to Distributed Clock (DC).
DC is a synchronized time clock that is shared by the master and I/O module. Using DC, it generates perfectly
synchronized interrupts so that the I/O module executes commands in exact timing. Each product has a range of
jitter in ns or less.
Frame Jitter for EtherCAT Masters