Control functions
7.8 Communicating with the PLC
SINAMICS V90, SIMOTICS S-1FL6
Operating Instructions, 04/2019, A5E36037884-007
289
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
03 h
20 h
0
1
2
Slave address
Function code (read)
Number of following data bytes (20 h: 32 bytes
≙
16 registers)
User data
0001 h
2F00 h
0004 h
3,4
5,6
7,8
40601: DS47 Control = 1 (request is processed)
40602: Function 2F h(47), response length 0 (fault)
40603: Error code: 0004 Response Not Ready (response has still not been
issued)