SensyMaster FMT230, FMT250
THERMAL MASS FLOWMETER | OI/FMT230/250-EN REV. C
57
0x04
Read Input Registers
The ‘Read Input Registers’ function code is used to read off the ‘Input Register’ of the device.
The query telegram is designed as follows:
Byte Description
1
Slave device code
2
Read Input Registers Function Code, 0x04.
3, 4
Input register address. 16-bit value indicating the address of the first input register to read.
5, 6
Input register count. 16-bit value indicating the number of input registers to read.
7, 8
Check sum (CRC) of the Modbus telegram
The reply telegram to a successfully processed query is designed as follows:
Byte Description
1
Slave device code
2
Read Input Registers Function Code, 0x04.
3
Number (n) of data bytes in the reply telegram
4 to (4+n)-1
Input register data.
(4+n),
(4+n)+1
Check sum (CRC) of the Modbus telegram
0x06
Write Single Register
The ‘Write Single Register' function code is used to write a value in one of the ‘Holding Register’ of the device.
The query telegram is designed as follows:
Byte Description
1
Slave device code
2
Write Single Register Function Code, 0x06.
3, 4
16-bit holding register address.
5, 6
Holding register value. 16-bit value indicating the value to write.
7, 8
Check sum (CRC) of the Modbus telegram
The reply telegram to a successfully processed query is designed as follows:
Byte Description
1
Slave device code
2
Write Single Register Function Code, 0x06.
3, 4
Holding register address. 16-bit value indicating the address of the holding register that was written.
5, 6
Holding register value. 16-bit value indicating the value that was written to the holding register.
7, 8
Check sum (CRC) of the Modbus telegram
