SFA-5000 • SFA-10000 EtherCAT
6.2.2 Communication messages
EtherCAT Datagram of CoE mode has the following structure:
Mbx Header
CoE Cmd
Cmd specific
data
type = 3
Number
res
Type
6 bytes
9 bits
3 bits 3 bits
0 … 1478 bytes
Mbx Header = 3 CoE mode
Number
= 0 in case of SDO messages
≠
0 in case of PDO messages, it defines the type of service
res
reserved bits
Type
= 0 reserved
= 1 Emergency message
= 2 SDO request
= 3 SDO response
= 4 Transmitted PDO (TxPDO)
= 5 Received PDO (RxPDO)
= 6 Remote transmission request of TxPDO
= 7 Remote transmission request of RxPDO
= 8 SDO information
= 9 … 15 reserved
Cmd specific data
PDO messages: are the process data, e.g. position value
SDO messages: standard CANopen frame
Transmit (tx) or receive (rx) “Type” is viewed from the Slave.
6.2.3 Process Data Objects (PDO)
PDO messages are used for transmitting or receiving process data in real time;
data to be transmitted or received is defined in PDO Mapping and managed by
Sync Manager PDO Mapping.
MAN SFA_5000_10000_EC E 1.0.odt
6 - EtherCAT® interface
60 of 84