Siemens SINAMICS G220 - Page 399

Table 14-39 Response if read request has still not been completed
 Value Byte Description
Modbus Appli‐
cation Header
- 0 … 6 -
Protocol Data
Unit
03h 7 Function code
0Eh 8 Number of data bytes following (14bytes ≙ 7 registers)
0001h 9, 10 40601: Check value 1 = request being processed
2F00h 11, 12 40602: Function code 2F h (47), response length 0 (error)
0004h 13, 14 40603: Error code 0004 (response has still not been issued)
Example
The following example describes writing parameter p1121.
Procedure for writing the parameter value of p1121:
1. The controller sends a "write parameter value" parameter request to the converter.
2. The controller sends a write request to the converter.
3. The converter responds to the write request.
Table 14-40 Write parameter request: Write parameter value of p1121
 Value Byte Description
Modbus Appli‐
cation Header
- 0 … 6 -
Protocol Data
Unit
10 h 7 Function code
0258h 8, 9 Register (40601)
000A h 10, 11 Number of registers to be written (40601 … 40610)
14h 12 Number of data bytes (ten registers of two bytes each = 20 bytes)
0001h 13,14 40601: DS47 Control=1 (activate request)
2F10h 15,16 40602: Function code 2Fh (47), request length 10 bytes (0Ah)
8002h 17,18 40603: Request reference = 80h, request identi󹪝er = 2h (write
parameter)
0101h 19,20 40604: DO-ID = 1, number of parameters = 1
1001h 21,22 40605: Attribute, number of elements = 1
0461h 23,24 40606: Parameter number = 1121
0000h 25, 26 40607: Subindex = 0
0801h 27, 28 40608: Format + number of values
4142h 29, 30 40609: Parameter value
6666h 31, 32 40610: Parameter value
Functions
14.5Modbus TCP communication
SINAMICS G220 converter
Operating Instructions, 04/2024, FW V6.2, A5E51781573B AB 397