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Network Communication

5.3.1 Communication Objects

5.3.1.1 Process Data Object - PDO

PDOs contain real time data with high priority identifiers. The data telegrams consist of a maximum of 8 bytes and can be interchanged among the individual sub-assemblies, as required. This data exchange can be optionally event controlled or performed in a synchronized manner. The event controlled mode allows the bus load to be drastically reduced permitting a high communication capacity at a low Baud rate. However, the various modes can also be processed as a mix (see chapter 5.3.4.2.20 "Object 0x1400– 0x141F, Receive PDO Communication Parameter")

5.3.1.1.1 PDO Protocol

This protocol is used to transmit data from/to the bus coupler without protocol overhead. PDOs consist only of the CAN identifier and the data field. No further protocol information is contained in a PDO. The contents of the data are defined by the mapping parameters and the transmission type by the communication parameters.

A differentiation is made between RxPDO (receipt PDO) and TxPDO (transmit PDO).

Receive Process Data Object (RxPDO)

Transmit Process Data Object (TxPDO)

WAGO-I/O-SYSTEM 750

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