Lenze EPM−T9XX Modular system - Manual (Page 213)

About CANopen
Structure of the CAN data telegram
9
Network via CANopen
9.1
9.1.1
L
9.1−1 EDSPM−TXXX−9.0−11/2009
9.1 About CANopen
The I/O system IP20 supports the CANopen communication module.
The CANopen protocol is a standardised layer−7 protocol for the CAN bus. This
layer is based on the CAN Application Layer (CAL) which was developed as a
universal protocol.
However, as the practice shows, applications with CAL were too complex for the
users. CANopen provides a uniform and simple structure for connecting the CAN
devices of the various manufacturers.
)
Note!
l The communication profile CANopen can be selected with
setting the node address (Node−ID).
– Information on how to proceed with the modular system is
included in the description of the CAN Gateway module in the
chapter "The modular system".
– Information on how to proceed with the compact system is
included in the description of the corresponding module in the
chapter "The compact system".
– Lenze setting: System bus (CAN)
l Additional information on CANopen can be found in the Lenze
CAN Communication Manual.
9.1.1 Structure of the CAN data telegram
Control field CRC delimit. ACK delimit.
Start RTR bit CRC sequence ACK slot End
Identifier User data (0 ... 8 bytes)
·
Network management
·
Process data
·
Parameter data 1 bit 11 bits 1 bit 6 bits 15 bits 1 bit 1 bit 1 bit 7 bits
Fig. 9.1−1 Basic structure of the CAN telegram
)
Note!
Only the identifier and the user data are relevant to the user. All
other data of the CAN telegram are automatically processed by
the system.