SDO Communication
CANopen Protocol
μCAN.8.dio-BOX
MicroControl Version 2.00
Page
42
8
8.3 SDO Communication
All parameters of the devices (organized in an object dictionary)
are accessed via the SDO service (Service Data Object). A SDO
message has the following contents:
ID
DLC
B0
B1
B2
B3
B4
B5
B6
B7
8
CMD
Index
Sub-
In-
dex
Data
For calculation of the SDO message identifier please refer to “In-
troduction” on page 39.
The Command Byte (
CMD
) has the following meaning:
Master wants to read from Slave
40h
Slave answers on the read-request
42h
Master wants to write to Slave
22h
Slave answers on the write-request
60h
The
Note
byte order for the fields "
Index
" and "
Data
" is least significant
byte first (Intel format).
The
Attention !
minimum time delay between two succeeding SDO-com-
mands must be greater than 20ms. Faster communication might
lead to an unpredictible device status.
