Service Data Objects (Sdo) - Kollmorgen S300 Interface Manual

CANopen communication profile
3.4.5

Service Data Objects (SDO)

SDOs are used to implement access to the Object Dictionary. The SDOs are required for
parametrerization and for status polling. Access to an individual object is made with a multiplexer
via the Index and Subindex of the Object Dictionary. The following communication protocols are
supported by S300/S700:
l
l
l
l
l
The definitions of the individual communication services and protocols can be found in DS301.
Examples of the usage of SDOs can be found in the appendix from page 115.
Since an SDO is a confirmed service, the system must always wait for the SDO response telegram
before it is allowed to transmit a new telegram.
3.4.5.1 Composition of the Service Data Object
An SDO consists of the following components:
Byte
Content
1.
20
Initiate SDO Download Protocol
Download SDO Segment Protocol
Initiate SDO Upload Protocol
Upload SDO Segment Protocol
Abort SDO Transfer Protocol
1 2
rw
The control byte (Byte 1):
The control byte determines whether the SDO should write or read the content of the entry
in the Object Dictionary. A description of the complete Object Dictionary for
S300/S700 can be found from p. 101.
Data exchange with the S300/S700 is governed by the CMS
multiplexed domain protocols standard, as described in the CAN standard DS 202.
To read data, the control byte must be written in the manner shown below:
Bit 7
Content ccs*=2
Þ client command specifier (ccs = 2 Þ initiate upload request)
* ccs
Þ
X free data
So a value of 0100 0000 (binary) or 40h has to be transmitted in the control byte.
The servo amplifier sends back a corresponding response byte:
Bit 7
Content scs*=2
Þ server command specifier (scs = 2 Þ initiate upload response)
* scs
Þ
n only valid for e = s = 1
if this is so, n contains the number of bytes that do not contain data
Þ
X free data
If reading is successfull, the response byte always has set the bits 0 and 1 (e = s = 1).
Encoded byte length in the SDO response:
0x43 - 4 bytes
0x47 - 3 bytes
0x4B - 2 bytes
0x4F - 1 byte.
If an error occurs, scs is set to 4, the response byte is 0x80 and the error information is in
the four byte data field. The decoding of the error can be found on p. 22.
11/2018
3 4
Index Subindex
6 5 4
X
6 5 4
X
Kollmorgen
5 6 7
Data
3 2 1
X X X
3 2 1
n e
CANopen for S300/S700
8
0
X
0
s