Omron C200HW-CORT21-V1, Руководство по эксплуатации

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Setting up a network
Section 3-3
38
COB-ID
To establish communication between CANopen nodes, their communication
objects (PDOs) must be linked to each other. This is done by configuring the
identifier part of the COB-IDs of the respective PDOs to the same value.
The COB-ID is a 32 bit object, which contains an 11-bit (or 29-bit) identifier:
bit 31 30 29 28-11 10-0
data 0/1 0/1 0 000000000000000000 11-bit identifier
Additional identifier bits (CAN 2.0B)
0 = 11-bit ID
1 = 29-bit ID
0 = RTR allowed on this PDO
1 = no RTR allowed on this
PDO
0 = PDO valid
1 = PDO not valid
Note: C200HW-CORT21-V1 supports only 11-bit identifiers, and no Remote
Transmission Requests (RTR). Therefore all its valid PDOs have COB-ID's
with the structure 40000xxxh. For PDO linking, only the identifier (xxx) is
relevant.
Example
The linking of PDOs is best described by an example. The following figure
shows a possible network configuration.
Nodes 2 to 5 are 8 digital input + 8 digital output modules. Node 1 is the
Network Management Master, which is also able to transmit and receive data
over the network. Note that the terms ‘input’ and ‘output’ are with respect to
the network.
Node 1 transmits 8 bits of data to Node 2 and Node 3 (multicast).
Node 2 and Node 4 transmit their input data to Node 1.
Node 3 transmits its input data to Node 5.
Node 5 transmits its input data to Node 4.
To realise this data exchange, the configuration manager must configure the
communication object identifiers (COB-IDs) of the PDOs. The configuration
manager can be part of the node that also functions as the NMT master, but
often a PC based configuration tool will be used. Refer to section 1-3-5 for
more details about COB-IDs.
Node 2
8 bit input
8 bit output
Node 3
8 bit input
8 bit output
Node 5
8 bit input
8 bit output
Node 4
8 bit input
8 bit output
NMT, Node 1
8 bit input
16 bit output