EtherCAT PDOs are transmitted cyclically in a fixed length. The standard set of PDO can be sent at up to 4000 Hz.
Each PDO mapping can be used for different use cases, for example a diagnostics mapping can be configured in one PDO mapping and this can be discarded for operation.
Mappings can also be added for different drives.
A total of four PDO mappings can be defined with up to 10 objects in each direction.
The defined mappings are configured in objects 0x1A00 - 0x1A03 (TxPDO Mapping) and 0x1600 - 0x1603 (RxPDO Mapping).
The PDO mappings that should be used are defined in the objects 0x1C12 (Incoming: SM Assignment 2) and 0x1C13 (Outgoing: SM Assignment 3).
Since the SM Assignment Mailboxes work as a triple buffer, only 0.3 kByte of data can be used in each PDO mapping.
To change the content of an object:
Disable the object by setting its subindex 0 to 0
Enter the objects that should be mapped to the mapping entry subindices 1 to n
Set subindex 0 to the number n of used entries
If the subindex 0 is not 0 a write access to any other subindex will only be possible if the entered value equals the stored value. This can be used to check the device configuration against the master configuration.
Used for defining the incoming PDO mapping 1
Used for defining the incoming PDO mapping 2
Used for defining the incoming PDO mapping 3
Used for defining the incoming PDO mapping 4
Used for defining the outgoing PDO mapping 1
Used for defining the outgoing PDO mapping 2
Used for defining the outgoing PDO mapping 3
Used for defining the outgoing PDO mapping 4
This object handles the SM assignment.
This object defines the master to slave communication (SDO and FoE)
This object defines the slave to master communication (SDO and FoE)
This object object defines the incoming PDO mappings to be used.
This object object defines the outgoing PDO mappings to be used.