Inquiry Regarding Modbus Implementation on nRF9160 Development Kit

[purushothaman]

Hi,
    

I am writing to seek guidance regarding the implementation of Modbus communication on the nRF9160 Development Kit.

As a developer who is relatively new to the concept of Modbus, I have been exploring the capabilities of the nRF9160 board and have come across sample code for Modbus RTU client and server implementations. However, I have some queries regarding the feasibility of using this functionality on my current setup.

Currently, I have only one nRF9160 Development Kit available for testing purposes. My primary objective is to perform both client and server operations using this single board without the need for additional hardware.

1. Is it possible to perform both client and server operations with just one nRF9160 board?
2. Can I utilize the UART TTL interface on the nRF9160 board for Modbus communication?
3. Given my setup, where I intend to use a computer as the master and the nRF9160 as the client, could you provide some insights or recommendations on how to proceed with this configuration?

Additionally, I am considering using Modbus software on my computer to act as the master in this setup. Is it feasible to use such software, and do you have any recommendations for Modbus software that would be compatible with this configuration? Can I utilize the UART TTL interface on the nRF9160 board to transfer data to Modbus software in my system? Given my setup, where I intend to use a computer as the master and the nRF9160 as the client, could you provide some insights or recommendations on how to proceed with this configuration?

Thank you for your attention to this matter. I look forward to your guidance and support in exploring Modbus functionality on the nRF9160 Development Kit.

Best regards,
Purushothaman M

[Naeem Maroof]

Hi

I have not worked with Modbus communication protocol, and I don't know if someone here is experienced in this.

But I can see that there are separate samples for client and server in zephyr. For sure we do not have any sample or example combining both for the same kit. Nonetheless, on nrf9160dk you have two uart interfaces connected with the nrf9160. So probably that should be doable.   

[purushothaman]

Hi,
  

1. Could you kindly specify which UART interface (UART1 or UART2) is being utilized for communication in the provided Modbus RTU sample code?

2. Can you provide information on the baud rate configuration used for UART communication in the code?
   
   where this uart configurations are specified in the code i could't find it?

[Naeem Maroof]

Hi

In the rtu_client sample:

the baud rate and other settings are shown

also, the zephyr_modbus_serial compatible is on uart1 and can be seen in the zephyr.dts: