Siemens SINAMICS V90 Operating Instructions Manual page 232

Control functions
7.7 Communicating with the PLC
The table below formats a response for successful write operation.
Byte Description
Header
01 h 0 Slave address
Number of following data bytes (20 h: 32 bytes ≙ 16 registers)
03 h 1 Function code (read)
20 h 2
User data
0002 h 3,4 40601: DS47 Control = 2 (request was executed)
2F04 h 5,6 40602: Function code 2F h (47), response length 4 bytes
8002 h 7,8 40603: Request reference mirrored = 80 h,
response identifier = 2 (change parameter)
0202 h 9,10 40604: V90 = 2 h, number of parameters = 2
Write the PLC command from registers 40601 to 40604:
The table below formats a response for unsuccessful write operation (write request still not
completed).
Byte Description
Header
01 h 0 Slave address
Number of following data bytes (20 h: 32 bytes ≙ 16 registers)
03 h 1 Function code (read)
20 h 2
User data
0001 h 3,4 40601: DS47 Control = 1 (request is processed)
2F00 h 5,6 40602: Function 2F h(47), response length 0 (fault)
0004 h 7,8 40603: Error code:
issued)
232
0004 Response Not Ready (response has still not been
SINAMICS V90, SIMOTICS S-1FL6
Operating Instructions, 09/2016, A5E36037884-002