Modbus RTU to Ethernet/IP communicator configuration



I try to use Anybus configuration manager to configure my Modbus RTU to Ethernet/IP gateway by using wizard.
In the screen to ‘create parameters’, why each parameter register is 6 digits xxxxxx, it supposes to be 5 digits.


Hi Hans,

Does it let you go onto the next page if there’s only 5 digits in the register or does it make you include 6?


I can go the next page, when create the new parameters, it shows 6 digits by default. if I manually input 5 digits, it puts a 0 before 4, then 6 digits.


it is always 6 digits, but I can move the next page


I’ll need to check into why there’s 6 digits, but can you try taking a look at this ticket for setting up reads/writes and see it helps for now?


I also saw this in the modbus manual

Modbus memory map and command overview


The picture shows the complete Modbus address range including Bit areas and Register areas (Words). The Modbus commands are also shown for the corresponding memory areas. The addresses given here are Modbus Register addresses. Many Device manuals ignore the leading digit of the address (i.e. 0, 1, 3 or 4). E.g. the address 40001 is very often referred to as 0001. One way to determine the leading digit required is based on the Modbus command specified.

Users should consult their specific serial device’s technical manual or their OEM device manufacturer to determine the actual Modbus Command code(s) implemented or required by their particular device. This will permit the user to determine the implied leading digit (number) of the data address (i.e. 0, 1, 3 or 4).

From the way it’s described in the manual it seems like the first digit is the function code


so in my case, I need to put 3 at the very first?


If you’re trying to read input registers then I think that should be correct


Thanks Tim,
I think it maybe 4 at the first for each address.
I need to use Rockwell PLC to read and write the data, what is about my setting in Rockwell PLC, will it work?


I’m not seeing any collisions, I’d try it out and see what you’re getting for responses