Synchronization Mode And Communications Cycle; Distributed Clock (Dc) Mode; Free-Run Mode - Omron 1 S Series User Manual

5 EtherCAT Communications
5-6 Synchronization Mode and Commu-
nications Cycle
1S-series Servo Drives Advance Type support the following synchronization modes.

• Distributed Clock (DC) Mode

• Free-Run Mode

Note SM Event Mode is not supported.
5-6-1

Distributed Clock (DC) Mode

A mechanism called distributed clock (DC) is used to synchronize EtherCAT communications.
The DC Mode is used for 1S-series Servo Drives Advance Type to perform highly accurate control in a
multi-axis system.
In DC Mode, the master and slaves are synchronized by sharing the same clock.
Interruptions (Sync0) are generated in the slaves at precise intervals based on this clock.
Servo Drive control is executed at this precise timing.
Communications Cycle (DC Cycle)
The communications cycle is determined by setting the output cycle of Sync0 signal on the master side.
Setting range : 125 µs/250 µs/500 µs/750 µs/1 to 10 ms (in 0.25 ms increments)
5-6-2

Free-Run Mode

You can use the Free-Run Mode when synchronization such as the DC Mode is not required.
In Free-Run Mode, slaves perform I/O processing, i.e. refresh I/O data asynchronously with the com-
munications cycle of the master.
Communications Cycle
The communications cycle is determined by the cycle time of the master.
Setting range : 125 µs to 100 ms
5 - 16
1S-series with Built-in EtherCAT Communications and Safety Functionality User's Manual (I621)