BUDE_Manual-CANopen_EN.doc
10/55
Baumer Hübner GmbH
23.10.2012/bja
Berlin, Germany
3.3.3
Service data communication
The service data objects correspond to the standards of the CiA. It is possible to access an object via index
and subindex. The data can be requested or where applicable written into the object.
General information on the SDO
Structure of an
SDO telegram
:
COB ID
DLC
Command
Object L
Object H Subindex Data 0 Data 1 Data 2 Data 3
An SDO-
COB ID
is composed as follows:
Master -> Encoder/Converter :
600h + Node ID
Encoder/Converter -> Master :
580h + Node ID
DLC
(data length code) describes the length of the telegram. This is composed as follows:
1 byte c 2 bytes 1 byte su no. of data bytes (0 - 4).
The
command byte
defines whether data is read or set, and how many data bytes are involved.
SDO command
Description
Data length
22h
Download request
Max. 4 Byte
Transmits parameter to encoder/converter
23h
Download request
4 byte
2Bh
Download request
2 byte
2Fh
Download request
1 byte
60h
Download response
-
Confirms receipt to master
40h
Upload request
-
Requests parameter from
encoder/converter
42h
Upload response
Max. 4 byte
Parameter to master with max. 4 byte
43h
Upload response
4 byte
4Bh
Upload response
2 byte
4Fh
Upload response
1 byte
80h
Abort message
-
Encoder/converter signals error code to
master
