Beckhoff FC5101, Documentation

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CANopen Communication
FC5101 and FC5102 45 Version: 2.0
of the 29-bit versions remains limited to unusual applications. It is therefore also not supported by a
Beckhoff's CANopen devices. The highest bit (bit 31) can be used to activate the process data object or to
turn it off.
A complete identifier list [
}
80] is provided in the appendix.
PDO linking
In the system of default identifiers, all the nodes (here: slaves) communicate with one central station (the
master), since slave nodes do not listen by default to the transmit identifier of any other slave node.
Fig. 36: Default identifier allocation: Master/Slave
Fig. 37: PDO linking: Peer to Peer
If the consumer-producer model of CANopen PDOs is to be used for direct data exchange between nodes
(without a master), the identifier allocation must be appropriately adapted, so that the TxPDO identifier of the
producer agrees with the RxPDO identifier of the consumer: This procedure is known as PDO linking. It
permits, for sample, easy construction of electronic drives in which several slave axes simultaneously listen
to the actual value in the master axis TxPDO.
PDO Communication Types: Overview
CANopen offers a number of possible ways to transmit process data (see also: Notes on PDO
Parameterization [ } 51] ).