The "Alarm Status" registers of the Modbus table of the TX Modbus slaves allow you to check whether the reading and writing of the slave registers have been well done.
The "Alarm Status" register is coded on 16 bits of which 6 bits are used to check whether the reading of the slave registers has been successful and 6 bits are used to check whether the writing in the slave registers (Hold type or Coil) has been well done out as shown in the "Status Registers" sheet below of the attached Modbus table:
Example: Reading and writing must be coded in the “Alarm Status” register
Here the value read is 3e3e (hexadecimal). Convert this hexadecimal value to 16-bit binary:
3e3e(hex) = 00111110 00111110 (binary)
111110: Only the first register of the slave has been read.
111110110: Writing was successful only in the first register of the slave.