ECM NH3CAN, Instruction Manual, Page: 12 / 35

12
5.0 Writing to the NH
3
CAN Module (SDO Write)
Configuration of the NH
3
CAN module is performed by writing to the Object Dictionary (OD)
and by issuing ECM CANopen OS Commands (OS Command). Both of these actions are
implemented using a Service Data Object Expedited Write (SDO Write). The format is as
follows:
SDO Write Tx
CAN id
byte 0 byte 1 byte 2 byte 3 byte 4 byte 5 byte 6 byte 7
0x600+NID Size OD lo OD hi Sub Data0 Data1 Data2 Data3
Size = 0x2F (1 byte write)
0x2B (2 byte write)
0x23 (4 byte write)
OD lo = low byte of OD address
OD hi = hi byte of OD address
Sub = Subindex of OD address
Data0 always contains the Least Significant Byte (LSB) of the data to be written to the OD.
A SDO Write will generate the following reply:
SDO Write Rx
CAN id
byte 0 byte 1 byte 2 byte 3 byte 4 byte 5 byte 6 byte 7
0x580+NID 0x60 OD lo OD hi Sub
Example: Write a 2 byte integer = 0x204 to OD address 0x5017 subindex 0 in the module with
NID = 0x10
SDO Write Tx
CAN id
byte 0 byte 1 byte 2 byte 3 byte 4 byte 5 byte 6 byte 7
0x610 0x2B 0x17 0x50 0x00 0x04 0x02
The module will reply as follows:
SDO Write Rx
CAN id
byte 0 byte 1 byte 2 byte 3 byte 4 byte 5 byte 6 byte 7
0x590 0x60 0x17 0x50 0x00