LS ELECTRIC L7NHF Series, Руководство пользователя

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3. EtherCAT Communication
3-1
3.
EtherCAT Communication
EtherCAT stands for Ethernet for Control Automation Technology. It is a communication method for
masters and slaves that uses Real-Time Ethernet, developed by the German company BECKHOFF
and managed by the EtherCAT Technology Group (ETG).
The basic concept of EtherCAT communication is that, when a DataFrame sent from a master passes
through a slave, the slave inputs the received data to the DataFrame as soon as it receives the data.
EtherCAT uses a standard Ethernet frame compliant with IEEE802.3. Therefore, based on the Ethernet
100BASE-TX, the cable can be extended up to 100 m, and up to 65,535 nodes can be connected. In
addition to this, when using a separate Ethernet switch, you can interconnect with the commonly used
TCP/IP.
3.1
Structure of CANopen over EtherCAT
This drive supports a CiA 402 drive profile. The Object Dictionary in the application layer includes the
application data and PDO (Process Data Object) mapping information from the process data interface
and application data.
The PDO can be freely mapped, and the content of the process data is defined by PDO mapping.
The data mapped to the PDO is periodically exchanged (read and written) between an upper level
controller and a slave by process data communication; the mailbox communication is performed
aperiodically; and all of the parameters defined in the Object Dictionary are accessible.
Sync
Manager0
Object Dictionary
SDO PDO Mapping
Application Layer
Mailbox Process Data
Data Link Layer
EtherCAT Physical Layer
EtherCAT
State
Machine
Registers
Servo Application
Sync
Manager1
Sync
Manager2
Sync
Manager3
FMMU0 FMMU1