Siemens SIMOCODE pro Function Manual page 102

Communication
2.3 Modbus communication
Function code 05 - Write Single Coil
Function
This function enables the Modbus master system to write an individual bit from the
SIMOCODE pro bit memory area.
A valid address from the bit memory area is expected as the start address. The selected
address must be designated as writable (see the tables in Section Modbus RTU data tables
(Page 277), "Access" column).
0000h for a logical zero and FF00h for a logical one are accepted as data. Any other value is
impermissible and given a negative acknowledgment.
Request message frame
Slave address
1 byte
Response message frame
Slave address
1 byte
Example
Controlling a motor connected to SIMOCODE pro from slave address 16 (assuming the
assignment of the process image corresponds to the default settings). For this purpose, bit
address 00 0x02 (see the tables in Section Modbus RTU data tables (Page 277)) is
controlled with logical one. This bit address lies within the process image output that can be
accessed both by bit access and by register access.
Request message frame
Slave address
1 byte
0x10
Response message frame
Slave address
1 byte
0x10
102
Function code Start address
1 byte 2 bytes
Function code Start address
1 byte 2 bytes
Function code Start address
1 byte 2 bytes
0x05 0x00 0x02
Function code Start address
1 byte 2 bytes
0x05 0x00 0x02
Data
2 bytes
Data
2 bytes
Data
2 bytes
0xFF 0x00
Data
2 bytes
0xFF 0x00
SIMOCODE pro - Communication
Function Manual, 11/2018, A5E40508495002A/RS-AC/003
CRC
2 bytes
CRC
2 bytes
CRC
2 bytes
0x....
CRC
2 bytes
0x....