INVT Goodrive350 Series, Operation Manual

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Communication extension card EtherCAT communication card
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6.4 Communication
6.4.1 CoE reference model
Object dictionary (OD)
SDO PDO mapping
Register
Mail box
Process data
SM0 SM2 SM1 SM3
EtherCAT data link layer
EtherCAT physical layer
EtherCAT
state
machine
GD350 application
Figure 6-3 CoE reference model
CoE network reference model consists of the data link layer and application layer. The data
link layer is responsible for EtherCAT communication protocol. CANopen drive Profile (DS402)
communication rules are embedded in the application layer. The object dictionary in CoE
includes the parameters, application data, and PDO mapping configuration information.
PDOs are composed of the objects (in the object dictionary) that can perform PDO mapping.
The content in PDO data is defined by PDO mapping. PDO data is periodically read and
written, which does not require searching the object dictionary. Mail box communication (SDO)
is not periodic, which requires searching the object dictionary.
Note: To parse SDO and PDO data correctly on the EtherCAT data link layer, it is necessary
to configure FMMU and Sync Manager (SM).
Table 6-4 EtherCAT Sync Manager configuration
Synchronization
management
Configuration Size Start address
Sync Manager 0
Assigned to receive
SDO
512byte 0x1000
Sync Manager 1
Assigned to send
SDO
512byte 0x1400
Sync Manager 2
Assigned to receive
PDO
128byte 0x1800
Sync Manager 3
Assigned to send
PDO
128byte 0x1C00