User Manual Of EL7-EC** AC Servo
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7.4 CANopen over EtherCAT (CoE)
7.4.1 Network structure of EL7-EC
EL7-EC DSP402
Object Dictionary
Service
Data
Object
PDO
mapping
Object
EtherCAT
State
Machine
ESC
register
Mailbox
Process data
FMMU0
FMMU1
FMMU2
SM2
SM3
SM0
SM1
EtherCAT physical layer
CANopen
DSP 402
CANopen
Over
EtherCAT
EtherCAT
Data link
layer
EtherCAT
application
layer
Figure 7.4 The structure of EL7-EC network module
The data link layer is mainly implemented by EtherCAT slave station controller (ESC).
EL7-EC EtherCAT application layer protocol mainly includes application part (CANopen
DSP402), object dictionary and communication function (red frame part), among which
object dictionary and communication function can be jointly called CoE part.
Object dictionary——Bridge of communication function and application part.
Communication function——Implementation of communication rules (SDO, PDO,
etc.)
Application part——Define the specific function of the device, such as the drive, IO
module.