Writing to a Holding Register Using Modbus Poll Master Software.

I want to send 1999 to a temperature indicator that accepts serial values into 40031 register. How can I write into a holding register using Modbus poll master software?

I am using serial communication using RS-485. I am new to this topic, and I am an intern. Anyone willing to help me on this please ping me on [email protected].

Thanks in advance,

There are so many settings that can cause Modbus RTU to not work. It pays to read a value from a slave before writing a value to a slave.

Can you successfully read the value in (4)0031?
Here's a procedure for writing multiple values to multiple Holding registers (4)xxxxx.

In ModPoll's command bar click on Function and from the drop down menu, select 16: Write Registers.

In the 16: Write Multiple Registers dialog box that comes up, edit
- the slave node ID number,
- the starting address,
- the number of registers (not 8 bit bytes, but 16 bit Modbus registers; 2 registers for floating point/real or long integers)
- the number format type (select from the drop down menu)

When you edit a register address, click on the Edit button and the register address will default initially to zero (register address = 0), but edit it to the value you want to write (0010 = 52.7). The value must conform to the number type you've selected.

When you click Send, the Modpoll with execute the function and the result will appear when that register is read.