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Each EtherCAT
®
layer consists of the building blocks as shown in
FMMU n
FMMU n
FMMU n
FMMU n
Application
RD/WR
Registers
PHY
Management
MII / EBUS
Port 0
MII / EBUS
Port 1
MII / EBUS
Port 2
MII / EBUS
Port 3
File
Access
ESC Address Space (DPRRAM)
TCP, UDP
Object Dictionary
PDO Mapping
IP
Process Data Interface (µC, SSI, I/O)
SDO
PDO
Appli-
cation
HTTP,
FTP,..
Application
e.g. CiA402 Drive Profile
....
...
VoE
FoE
CoE
CoE
EoE
Mailbox DLL
EtherCAT Processing Unit
and Auto-Forwarder with Loop Back
EtherCAT Slave Controller (ESC)
Mailbox
SyncMAN0 MdxOut
SyncMAN1 MdxIn
SyncMAN2
FMMU n
PHY
PHY
LVDS
SII
EEPROM
FCS
LRW
ECAT HDR
Ethernet HDR
FPWR
More Datagrams..
Mailbox Data
Process Data
SyncMAN3
Process Data
Application
Layer
(AL)
Data
Link
layer
(DL)
Physical
Layer
(PL)
0x0000
0x1000
RJ45
WKC
WKC
HDR
HDR
Mag
RJ45
Con
Mag
Figure 11.62:
EtherCAT
®
Slave Stack overview
11.10.3
Physical Layer
The EtherCAT
®
Physical Layer defines the EtherCAT
®
transport media over
which EtherCAT
®
frames are sent and how signals should be encoded and
decoded over this media.
11.10.4
Data Link Layer
The EtherCAT
®
Data Link Layer controls access to the transport medium and
provides basic time
-
critical messaging communication between devices
connected to the EtherCAT
®
field bus. Within the Data Link Layer the following
building blocks can be identified:
GEN3t
230
I3995-3.1 en HBM: public