Siemens SINAMICS G120 CU230P-2, Operating Instructions Manual, Page: 159 / 346

Configuring the fieldbus
6.3 Communication over CANopen
Frequency inverters with Control Units CU230P-2 HVAC, CU230P-2 DP, CU230P-2 CAN
Operating Instructions, 01/2011, FW 4.4, A5E02430659B AD
157
Structure of the SDO protocols
The SDO services use the appropriate protocol depending on the task. The basic structure is
shown below:
n user data Header information
Byte 0 Byte 1 und 2 Byte 3 Byte 4 ... 7
CS index sub index length
● The protocol type is contained in byte 0:
–
2F hex: write 4 bytes
– 2B hex: write 3 bytes
– 27 hex: write 2 bytes
– 23 hex: write 1 byte
– 40 hex: read request
– 4F hex: read 4 bytes
– 4B hex: read 3 bytes
– 47 hex: read 2 bytes
– 43 hex: read 1 byte
– 60 hex: write acknowledgment
– 80 hex: error
● Bytes 1 and 2 contain the index (SINAMICS parameter number)
● Byte 3 contains the subindex (SINAMICS parameter index)
● Bytes 4 … 7 contain the data corresponding to the second position of byte 0. In the case
of an error, these bytes contain the abort code