Appendix
General information about the system bus (CAN)
Parameter data transfer
14
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EDBCSXA064 EN 3.2
14.7.4.1 User data
Structure of the parameter data telegram
User data (up to 8 bytes)
1. byte 2. byte 3. byte 4. byte 5. byte 6. byte 7. byte 8. byte
Command
Index
Low byte
Index
High byte
Subindex
Data 1 Data 2 Data 3 Data 4
Low word High word
Low byte High byte Low byte High byte
Display
Note!
The user data is shown in motorola format.
Examples for parameter data transfer can be found from 456.
Command
The command contains the services for writing and reading the parameters and
information on the length of the user data:
Command
Bit 7
MSB
Bit6 Bit5 Bit4 Bit3 Bit 2 Bit 1 Bit 0
LSB
Command specifier (cs) toggle (t) Length e E
Write request 0 0 1 0
00 = 4 bytes
01 = 3 bytes
10 = 2 bytes
11 = 1 byte
1 1
Write response 0 1 1 0 0 0
Read request 0 1 0 0 0 0
Read response 0 1 0 0 1 1
Error response 1 0 0 0 0 0 0 0
Tip!
Further commands are defined in the CANopen specification DS301,V4.02
(e.g. segmented transfer).