Communication
11.4 Communication via MODBUS TCP
Drive functions
Function Manual, 11/2017, 6SL3097-4AB00-0BP5
869
Table 11- 31 Response for unsuccessful read operation - read request still not completed
Function code (read)
Number of following data bytes (20 h: 32 bytes ≙ 16 registers)
0001 h
2F00 h
0004 h
9,10
11,12
13,14
40601: Check value 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
Examples: Write parameter
Table 11- 32 Write parameter request: Writing the parameter value of p1121 from device number 17
MBAP header
0258 h
000A h
8,9
10,11
Function code (write multiple)
Register start address
Number of registers to be written to (40601 … 40610)
Number of data bytes (10 registers, each 2 bytes = 20 bytes)
2F10 h
8002 h
0101 h
1001 h
0461 h
0000 h
0801 h
4142 h
15,16
17,18
19,20
21,22
23,24
25,26
27,28
29,30
40601: C1 (activate request)
40602: Function 2F h (47), request length 16 bytes (10 h)
40603: Request reference = 80 h, request identifier = 2 h (write)
40604: DO-Id = 1, number of parameters = 1
40605: Attribute, number of elements = 1
40606: Parameter number = 1121
40607: Subindex = 0
40608: Format + number of values
40609: Parameter value 12,15
Table 11- 33 Start parameter request: Writing the parameter value of p1121 from device number 17
0258 h
0007 h
8,9
10,11
Register start address
Number of registers to be written to (40601 … 40610)