Hello,

we have a TCP ModBus RFID reader connected to an S7-1200. The communication is working, but it occasionally fails. The reader stops reading cards and remains in a LOCK state. Old data also remains in the buffer, and new data doesn't appear. Does anyone have a sample project to set up a TCP ModBus reader on an S7-1200/1500?

https://inveo.com.pl/rfid-readers/nano-rfid/

Thank you.

Marek.

Hello,

it is first important to understand Modbus protocol generally because it can be possible you will have some problems where you don't know what problem is. It is easy to start learn and test Modbus TCP with 2 PC apps and see how it works. It is not easy and I don't expect that someone will share some prj with your exactly reader conencted. All is described in TIA system maual and Online help to expected block. You need have then correctly prepared some state machine in your code and change input parameters as your exact step requires. Pay attention to CLIENT block how it works (conenction established, run poll data, stop, disconenct), this is very important to know because you will need it with your code preparation.

Reader is in hang and can't work further. This seems like not correctly handled code especially at that error situations like forced disconenction from Reader, errors with some not correct parameters set during runtime or some error return code to check and pass correctly further, so it is very hard to recommend something. You need carefully trace your code and do maybe some checks.

Thank you Ivan, problem solved with switching disconnect input  of MB_client block in our sequence code.

Regards

Marek.

Hello,

many thanks for your update and glad you've solved this problem.