Lenze 931K - Manual (Page 20)

CANopen communication
Parameter data transfer (SDO transfer)
Telegram structure
5
l
20 KHB 13.0002−EN 4.1
Command code
11 bits 4 bits User data (up to 8 bytes)
1st byte 2nd byte 3rd byte 4th byte 5th byte 6th byte 7th byte 8th byte
Identifier
Data
length
Command
code
Index
low byte
Index
high byte
Subindex
Data 1 Data 2 Data 3 Data 4
Error code
The command code contains the services for writing and reading parameters and the
information on the length of the user data.
Structure of the command code:
Write command code
Bit 7
MSB Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
LSB
Comment CS 0 Length e s
Write command / write request 0 0 1 0 x x 1 1 CS: command
specifier
User data length
is coded in bits 2
and 3:
l 00 = 4 bytes
l 01 = 3 bytes
l 10 = 2 bytes
l 11 = 1 byte
Response to write command / write
response 0 1 1 0 x x 0 0
Read command code CS 0 Length e s
Read command / read request 0 1 0 0 x x 0 0
Response to read command / read
response 0 1 0 0 x x 1 1
Error command code CS 0 Length e s
Error response 1 0 0 0 0 0 0 0
The command code specifies whether a value is to be read or written. The command code
also determines the data length (1 byte, 2 bytes, 4 bytes).
Write command code
4−byte data
(5th ... 8th
byte)
2−byte data
(5th and 6th
byte)
1−byte data
(5th byte)
hex hex hex
Write command / write request
(Send parameters to the drive) 23 2B 2F
Response to write command / write response
(Response of the drive controller to the write request
(acknowledgement)) 60 60 60
Read command code
Read command / read request
(Request to read a parameter from the drive controller) 40 40 40
Response to read command / read response
(Response to the read request with the actual value) 43 4B 4F
Error command code
Error response
(The drive controller signals a communication error) 80 80 80