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Shenyang Guangcheng Technology Co., Ltd.
CANopen bus coupler
—
GCAN-IO-8000
Product data sheet
Shenyang Guangcheng Technology CO.LTD.
4. Predefined messages or special function objects
Predefined messages or special function objects provide specific functions for
CANopen devices, which is convenient for CANopen master to manage slave stations.
In the CANopen protocol, the COB-ID has been predefined for special functions,
which mainly have the following special messages:
Synchronization (SYNC), the message object mainly realizes the synchronous
transmission of the entire network, each node uses the synchronization message
as the PDO synchronization trigger parameter, so the COB-ID of the
synchronization message has a higher priority and the shortest Transmission time
Time Stamp object (Time Stamp), providing a common time reference for each
node;
Emergency object (Emergency), when an error occurs in the device, the object is
triggered, that is, the device internal error code is sent;
Node/Life Guarding, the master node can obtain the status of the slave node
through node protection. The slave node can obtain the status of the master node
through life protection;
Start the message object (Boot-up), send the object to the network after the
initialization of the node, and enter the pre-operation state.
B.5 CANopen network configuration
In the CANopen protocol description text DS305, a network configuration protocol is
defined, that is, the network configuration service LSS (Layer Setting Service), which
uses the CANOpen module with the LSS master function to query or modify the
CANOpen module with the LSS slave via the CAN bus. Certain parameters.
By using LSS, you can query or modify the following parameters:
Node-ID of CANopen slave
;
Bit timing parameters of physical layer (baud rate)
;
LSS address (feature object 1018h).