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CANopen communication
About CANopen
Identifier
5
16
KHB 13.0003-EN 2.0
5.1.2
Identifier
The principle of the CAN communication is based on a message-oriented data exchange
between a sender and many receivers. All nodes can send and receive
quasi-simultaneously.
The
identifier
in the CAN telegram - also called
COB-ID
(
Communication Object Identifier
)
- is used to control which node is to receive a sent message. In addition to the addressing,
the identifier contains information on the priority of the message and on the type of the
user data.
Except for the network management and the sync telegram, the identifier contains the
node address of the controller:
Identifier (COB-ID) = basic iden adjustable node address (node ID)
The identifier assignment is specified in the CANopen protocol.
The basic identifier ex works is preset to the following values:
Object
Direction
Basic identifier
from the drive
to the drive
hex
SDO
(parameter data channel)
X
580
X
600
PDO1
(process data channel 1)
TPDO1
X
180
RPDO1
X
200
PDO2
(process data channel 2)
TPDO2
X
280
RPDO2
X
300
PDO3
(process data channel 3)
TPDO3
X
380
RPDO3
X
400
RPDO4
X
500
SYNC
080
Emergency
X
080
Heartbeat/boot-up
X
700
NMT
000
5.1.3
Node address (node ID)
Each node of the CAN network must be assigned with a node address (also called
node ID
)
within the valid address range for unambiguous identification.
ƒ
A node address may not be assigned more than once within a network.