Omron CJ1W- ECT21, Operation Manual

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4 EtherCAT Communications
4 - 8 CJ-series EtherCAT Slave Units Operation Manual (W541)
These assignments determine the PDOs to use for communications between the EtherCAT master and
slave.
When assigning PDOs to the EtherCAT Slave Unit, refer to the IN and OUT data area size that have
been configured for the EtherCAT Slave Unit.
Assign PDOs of the same size as the setting value. PDOs are not assigned by default to an EtherCAT
Slave Unit. An example is shown in the table below.
Refer to 3-3-2 Details of the Allocated DM Area Words on page 3-9 for the I/O Communication Area
Reference Table.
Refer to 4-4-2 PDO Mappings on page 4-5 for PDO Mapping of the EtherCAT Slave Unit.
Precautions for Correct Use
The IN and OUT data area size allocation for the EtherCAT Slave Unit must be the same size
as the PDO mapping for the EtherCAT master. Refer to
3-3-1 Overview of the Allocated DM
Area Words on page 3-9. If the sizes do not match, an error will occur.
Assigning PDOs to EtherCAT Slave Units
I/O communication area reference table
PDO assignment
Name Offset Value
OUT data area size m + 9 64 hex (100 bytes) 258th receive PDO Mapping
IN data area size m + 12 32 hex (50 bytes) 257th transmit PDO Mapping