Good Morning, I’ve configurated ethernet port 1 of my APC810 - AR A4.34 as modbus server, but when I connect (ETH 1 mapping) a variable UINT to a channel IR Input Register defined in the configuration, automatically this the PV is “forced” and I can’t write it in my code. Same for Holding register:…

Hi Marcus Thank you for your reply. To update our discussion: i gave up the option to use native Modbus Server Configuration for a series of problems (this option is available with AS Runtime from A4.34 or more recent versions, now I work with V4.02 version). I just change my question: I need to…

Hi Massimo, welcome to the Community! I may be misunderstanding, but it sounds like you’re trying to write to a variable (via code) that you have mapped to an I/O input? This is not possible because the input will be overwritten with the physical input value every cycle. If I’m misunderstanding, le…

Hi Marcus, thank you for your reply. I try to explain my situation: ETH1 → Configuration (as modbus server) I define an Input Register Channel, address 4500, type UINT. I can write this value by changing the mapped variable (but the PV used for mapping must be defined as local to program, if …

Hi Massimo, Sorry for taking so long to reply on this. I must have missed the notification and didn’t see your reply until now. Do you still need help with this topic? I’m still a little confused what’s happening here, but it sounds like you’re attempting to change a variable in code, and that var…

Hi Massimo, Happy to help where I can! I’m not very familiar with this library, but just from glancing at the source code you provided, it uses the AsTCP library for opening ports and communicating. The first step in using this library is to call the TcpOpen function block. This function block let…

Configuration of Ethenet Port 1 of APC810-AR A4.34 as Modbus server

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Massimo_Q (Massimo Quaglianello) May 1, 2025, 12:45pm 2

NB: The AS version is 4.3

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Configuration of Ethenet Port 1 of APC810-AR A4.34 as Modbus server

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