
SFA-5000 • SFA-10000 EtherCAT
6.2.4 Service Data Objects (SDO)
SDO messages are issued via Mailbox (low priority data); Segmented SDO Service
and SDO Complete Access are not supported (transfer of low size data and one
sub-index at a time).
“CoE Cmd type” = 2 or 3
Structure of “Cmd specific data”:
Cmd specific data
SDO control
Index
Sub index
Data
Data optional
8 bits
16 bits
8 bits
32 bits
1 … 1470 bytes
SDO control
standard CANopen SDO Service
Index
parameter index
Sub index
parameter sub-index
Data
parameter value
Data optional
optionally, more then 4 bytes of data can be sent in one frame.
Full mailbox size usable.
Index and sub-index values are described in the “Object Dictionary”.
6.2.5 Object dictionary
The most important part of a device profile is the Object Dictionary. The Object
Dictionary is essentially a grouping of objects accessible via the network in an
ordered, pre-defined mode. Each object within the dictionary is addressed using
a 16-bit index.
The Object Dictionary can contain a maximum of 65,536 entries.
The user-related objects are grouped in two main areas: the Communication
Profile Area and the Standardised Device Profile Area. The objects are all
described in the XML file.
The
Communication Profile Area
at indexes from 1000h to 1FFFh contains the
communication specific parameters for the EtherCAT network. These entries are
common to all devices. PDO objects and SDO objects are described in this
section. The Communication Profile Area objects comply with the “CiA Draft
Standard Proposal 301. Application Layer and Communication Profile”. Refer to
the “Communication Profile Area objects (DS 301)” section on page 63.
The
Standardised Device Profile Area
at indexes from 6000h to 9FFFh
contains all data objects common to a class of devices that can be read or
written via the network. The device profiles may use entries from 6000h to
9FFFh to describe the device parameters and the device functionality. The
Standardised Device Profile Area objects comply with the “CiA Draft Standard
406 CANopen Device profile for encoders”. Refer to the “Standardised Device
Profile Area objects (DS 406)” section on page 68.
MAN SFA_5000_10000_EC E 1.0.odt
6 - EtherCAT® interface
61 of 84