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ORSO2001

Master and Slave at same time...

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Dear Alls,

I have to set up my Unistream to works at same time as Slave by Modbus RTU TCP and Masert by Modbus RTU RS485.

I already wrote the program part about slave (Modbus TCP) than I set PLC communications->Protocols->MODBUS->Slave->Panel Ethernet...I have set the registers and "wrote" the code...now I am approcing the Slave side...my question is:

I must use/set the same PLC communications->Protocols->MODBUS->Master->RS485 or I can mix/use the first with the PLC communications->Physical->Serial COM ?

I hope that my qestion is clear enough.

thanks

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ok...I found what I have to do....and also reading again my first post this has no sense...sorry usually I used unitronics as master using the "advanced modbus"...now I am trying to use "periodic/aperiodic" and at this point I have few questions:


- using "advanced modbus" if a data exchange don't works I use an instruction to empty the buffer to try again...using "periodic/aperiodic" this works automatically or I have to do something?


- when I compile the project I have a warning like: Do NOT place "COM: MODBUS" Ladder elements on the bus bar, or anywhere it will be continuously activated.
Use a delay of 10-50 msec between requests. Click on "Find All Elements" to locate all of the instances where it is used in the program
...I placed a "P" contact and a "modbus aperiodic trigger" to do some test...this warning is for safety or I am missing something?

thanks

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I also have that error- Do NOT place "COM: MODBUS" Ladder elements on the bus bar, or anywhere it will be continuously activated.
Use a delay of 10-50 msec between requests. Click on "Find All Elements" to locate all of the instances where it is used in the program

Also the command is not being called continuously (with a positive transition contact).

The program appears to work OK,but I still get this error at each download.

Any help would be appreciated

image.png.e32c7b0b22121f3568e276136ce8b793.png

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It is just a warning, ignore it. We cannot detect (unless the element is directory on bus bar) that it will be called continuously or not), since it  might be on a bus bar of another function that is called through a timer, or the other way around: not on bus bar, but after a Contact that is always open dues to the state of the connected bit.

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