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EtherCAT Communications Protocol (CoE)
The MG80-EC applies the device profile of the open network standard “CAN
application protocol” to EtherCAT devices, so it uses “CAN application protocol
over EtherCAT (CoE)”.
The figure below shows the structure of CoE in the MG80-EC.
CAN application protocol has two types of object dictionaries, PDO (Process Data
Object) and SDO (Service Data Object) .
PDO is composed of object dictionaries that can be mapped. The process data is
defined by PDO mapping. PDO is primarily used in PDO communications for
regularly exchanging process data.
Moreover, SDOs can read and write all object dictionaries and are used in non-
fixed-cycle type communications.
MG80-EC EtherCAT Slave Units
Application layer
Slave application
Object dictionary
Communications
status transitions
SDO (mailbox)
PDO mapping
PDO (cyclic)
Registers
Mailbox
Process data
SyncManager
FMMU
EtherCAT data link layer
EtherCAT physical layer
Содержание MG80-EC
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