Siemens SITRANS LG270 Operating Instructions Manual page 89

Parameter
Start Address
Register Value
FC4 Read Input Register
With this command, any number (1-127) of input registers can be read out. The start register, from
which the readout should start, and the number of registers are transmitted.
Request:
Parameter
Function Code
Start Address
Number of Registers
Response:
Parameter
Function Code
Start Address
Register Value
FC6 Write Single Register
With this function code an individual holding register can be written.
Request:
Parameter
Function Code
Start Address
Number of Registers
Response:
Parameter
Function Code
Start Address
Register Value
FC8 Diagnostics
With this function code different diagnostic functions can be triggered or diagnostic values read out.
Request:
Parameter
Function Code
PBD-51041066
Length
2 Bytes
N*2 Bytes
Length
1 Byte
2 Bytes
N*2 Bytes
Length
1 Byte
2 Bytes
N*2 Bytes
Length
1 Byte
2 Bytes
2 Bytes
Length
1 Byte
2 Bytes
2 Bytes
Length
1 Byte
SITRANS LG270 - Operating Instructions
Code/Data
2*N
Data
Code/Data
0x04
0x0000 to 0xFFFF
1 to 127 (0x7D)
Code/Data
0x04
2*N
Data
Code/Data
0x06
0x0000 to 0xFFFF
Data
Code/Data
0x04
2*N
Data
Code/Data
0x08
89