Siemens SIRIUS 3RW5 - Page 103

Messages and diagnostics
7.2 Function Codes
SIRIUS 3RW5 Modbus communication module
Equipment Manual, 03/2020, A5E43676481002A/RS-AC/003
103
7.2.3 Function Code 05 (Write Single Coil)
This function enables the writing of an individual bit from the 3RW5 bit memory area by the
Modbus TCP client system or the Modbus RTU master system.
A valid address from the bit memory area is expected as the start address. The selected
address must be designated as writable in the data tables in chapter Data tables (Page 136).
0x0000 for a logical zero and 0xFF00 for a logical one are accepted as data. Any other value
is impermissible and given a negative acknowledgment.
Request telegram
Modbus TCP:
Address Field
Function Code
Start address
Data
7 bytes
1 byte
2 bytes
2 bytes
-
0x05
0x8200
0xFF00
Modbus RTU:
Slave address
Function Code
Start address
Data
CRC
1 byte
1 byte
2 bytes
2 bytes
2 bytes
-
0x05
0x8200
0xFF00
-
Response telegram
Modbus TCP:
Address Field
Function Code
Start address
Data
7 bytes
1 byte
2 bytes
2 bytes
-
0x05
0x8200
0xFF00
Modbus RTU:
Slave address
Function Code
Start address
Data
CRC
1 byte
1 byte
2 bytes
2 bytes
2 bytes
-
0x05
0x8200
0xFF00
-