How exactly is AS used to configure Modbus IO station to generate an XML for use with ModbusTCP Toolbox?

[c433303 (M S)]

Hello all,

this topic is marked solved, but I do not see a suitable solution to be honest. I am in a same exact ditch. 4PPC70 panel + BC0087 with CM8281 mixed IO module after it.

What have I tried so far: Simply dragging a BC0087 to the project in AS and adding CM8281. This is added as an unconnected module, so I can not configure it, I can not drag it to ETH port where I already have three ModbusTcp_any devices, nothing. So first question/issue would be - how exactly is AS used to configure Modbus IO station to generate an XML for use with ModbusTCP Toolbox?

I have decided to see if at least default configuration works. Changed IP to my desired range using toolbox, that went OK. Added this IP as a ModbusTcp_any and configured FC3 input reading for first 7 words and writing first two words, as per the excel help file.

Reading works, writing does not.

I have tried CAS Modbus Scanner. FC3 reading from offset 1 yields correct data:
Address 40004 in CAS is address 0x0003 in Excel and those are digital inputs. Excellent.
As you can see, this value is 1, because I connected first DI on card to 24V

Same is shown in AS monitor mode.

For writing, I used following logic. Excel suggests the 0x0800 address is the two DO I have. Since CAS Modbus Scanner uses +1 notation, I am trying to write “3” to address 0x801 = 2049.
Output:

The address 2049 is correct, 2048 yields illegal write, since it would be trying to write to read only registers.

With AS, I am using the following configuration:

I keep getting a MODBUS error with error counter going up and no reaction from the card of course.

Can someone shine more light on this?
Thank you

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Originaly added to this already closed topic. Connectivity between 4PPC30.043F-21B & X20BC0087 via Ethernet. @gohe can you share with us your findings?

[c433303 (M S)]

Traditional self-reply: No wonder I got errors, watchdog got triggered.
After clearing it by writing 0xC1 to 0x1044, all is well and writing to outputs seems to work.

However, the XML configuration of BC0087 and modules connected to it is still unclear to me.

[tommi.piiparinen]

You will need to create a configuration in Automation Studio and select the “ModbusCPU” as the CPU.

Add and configure your I/O Modules

Build the configuration and find the output files in the following folder.

<ProjectFolder>\Temp\Objects\<ConfigurationName>\ModbusCPU\AsFDOutput

The output files also include nice documentation for the generated station.

[c433303 (M S)]

Thank you Tommi, that helped. I found out that I am actually good with the default config of the module (at least for now), but glad I learned something new.