Write Parameter - Siemens SINAMICS G110M Function Manual

Communication via RS485
5.4 Communication using Modbus RTU
Table 5- 27 Response for unsuccessful read operation - read request still not completed
Value Byte Description
11 h 0 Slave address
Number of following data bytes (20 h: 32 bytes ≙ 16 registers)
03 h 1 Function code (read)
20 h 2
0001 h 3,4 40601: Check value 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)
xx h 9 CRC "Low"
xx h 10 CRC "High"
5.4.7.2

Write parameter

Example: Set p1121 = 12.15
Table 5- 28 Write parameter request: Writing the parameter value of p1121 from slave number 17
Value Byte Description
11 h 0 Slave address
10 h 1 Function code (write multiple)
0258 h 2,3 Register start address
000A h 4,5 Number of registers to be written to (40601 ... 40610)
14 h 6 Number of data bytes (10 registers, each 2 bytes = 20 bytes)
0001 h 7,8 40601: C1 (activate request)
2F10 h 9,10 40602: Function 2F h (47), request length 16 bytes (10 h)
8002 h 11,12 40603: Request reference = 80 h, request identifier = 2 h (write)
0101 h 13,14 40604: DO-Id = 1, number of parameters = 1
1001 h 15,16 40605: Attribute, number of elements = 1
0461 h 17,18 40606: Parameter number = 1121
0000 h 19,20 40607: Subindex = 0
0801 h 21,22 40608: Format + number of values
4142 h 23,24 40609: Parameter value 12,15
6666 h 25,26 40610: Parameter value
xx h 27 CRC "Low"
xx h 28 CRC "High"
142
0004 Response Not Ready (response has still not been
Function Manual, 04/2018, FW V4.7 SP10, A5E34229197B AE
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