EM58 • HS58 • HM58 POWERLINK
Examples:
Direction
Communication parameter
Mapping parameter
RPDO
1400h
1600h
1401h
1601h
...
...
TPDO
1800h
1A00h
1801h
1A01h
...
...
6.11.4 SDO objects
To access the entries of the Object Dictionary of a device via Ethernet
POWERLINK a set of command services is specified.
An SDO client establishes a connection to an SDO server and issues a specific
command (read from or write to an object). This connection is unicast, allows
access to all objects of a remote node and is not deterministic (i.e. there is no
guarantee on how long the response takes after sending a request). SDO
communication takes place in the asynchronous phase and can be embedded in
a POWERLINK Asynchronous Send (ASnd) frame or in a UDP/IP packet.
SDO communication attends to the Client / Server model.
6.12 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 fashion. 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 three main areas: the Communication
Profile Area, the Manufacturer Specific Profile Area and the Standardised Device
Profile Area. The objects are all described in the XDD file.
The
Communication Profile Area
at indexes from 1000h to 1FFFh contains the
communication specific parameters for the POWERLINK network. These entries
are common to all devices. NMT services, PDO objects and SDO objects are
described in this section. The Communication Profile Area objects comply with
the “CiA Draft Standard Proposal 301 CANopen Application layer and
communication profile”. Refer to the “6.12.1 Communication Profile Area
objects (DS 301)” section on page 74.
MAN EM58_HS58_HM58 PL E 1.1.odt
POWERLINK interface
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