Features; Ethercat Free-Run And Distributed Clock Modes - ADLINK Technology ECAT IO Series User Manual

1.2 Features

Supports up to 100μs EtherCAT cycle time with DC mode
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Status holding mode when disconnected
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Connects up to 256 modules
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Easy maintenance by hot-plugging
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Flexible terminal block design for alternate wiring
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Compatible with APS function library
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Same wiring and layout as HSL IO
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1.2.1

EtherCAT Free-Run and Distributed Clock Modes

EtherCAT is a real-time Ethernet communication protocol that is
used in industrial automation systems. It supports two different
synchronization mechanisms: Free-Run and Distributed Clock.
Free Run Mode
Free-Run is the default synchronization mechanism used by
EtherCAT. In this mechanism, each slave device uses its own
internal clock and is responsible for maintaining its own synchroni-
zation with the EtherCAT master. The master sends out the con-
trol data and each slave reads this data, performs its required
task, and sends its response back to the master.
DC Mode
In DC mode, all devices on the EtherCAT network use a shared,
synchronized clock to determine when to perform their tasks. This
ensures that all devices on the network are working together in a
coordinated manner. The Distributed Clock mechanism requires
that each slave device has a hardware clock that is synchronized
with the master clock. The master sends out periodic synchroniza-
tion messages, and each slave adjusts its clock based on these
messages. Once all devices on the network are synchronized,
they can all perform their tasks at exactly the same time, with no
timing discrepancies.
ECAT IO Series
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