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Shenyang Guangcheng Technology Co., Ltd.
CANopen bus coupler
—
GCAN-IO-8000
Product data sheet
Shenyang Guangcheng Technology CO.LTD.
Figure A3 Producer consumer model
PDO communication has no protocol, and the content of PDO data is defined by
its CAN-ID (also called COB-ID);
Each PDO is described by 2 objects in the object dictionary:
PDO communication parameters, which define the COB-ID, transmission type
and timing period used by the device;
PDO mapping parameter, the mapping parameter contains a list of objects in the
object dictionary, these objects are mapped to the corresponding PDO, including
the length of the data (unit: bits), both producers and consumers must know this
mapping parameter, Only then can the PDO content be correctly interpreted.
The content of the PDO message is predefined. If the PDO supports variable PDO
mapping, the PDO can be configured through SDO;
PDO can have multiple transmission methods:
Synchronous
transmission
(to
achieve
synchronization
by
receiving
synchronization objects), synchronous transmission can be divided into aperiodic
and periodic transmission. Acyclic transmission is pre-triggered by remote frames
or pre-triggered by object-specific events specified in the device sub-protocol.
Periodic transmission is achieved by receiving a synchronization object (SYNC),
which can be set to trigger from 1 to 240 synchronization objects;
Asynchronous transmission (triggered by a specific event), which can be
triggered in two ways. The first is to trigger the transmission of PDO by sending a
remote frame with the same COB-ID of PDO, and the second is specified in the
device sub-protocol Object specific events to trigger (for example, timing
transmission, data state change transmission, etc.).