Question

How can we define a Modbus slave. I have done the settings for Modbus Serial Master in 1st router (i.e; master) that is RS232 Configuration and RS232 Slave Device's list. But I want to ask do I have to do some configuration in 2nd Router (i.e; slave) or not?

Also is it right to connect RX to TX and TX to RX for RS232 communication.

Answer 1

Hi,

If the device is running on the serial interface and not TCP, then you can just have one Master router and that's it.

If you're running on TCP and want to read/set data of the second router, then both router must be set as Master and Slave. 

About RX and TX:

Yes, it means that you're connecting TX (transmitter) to RX (receiver).

To give a credit to author of this article I'm going to link it here, so you could read it:

https://www.douglaskrantz.com/SCConnectingRS232.html

EB.

Comments

Thanks for the detailed link about wiring TX,RX.

https://wiki.teltonika-networks.com/view/RUT955_Modbus#RS232

I followed this.

Yes I am using two routers out of which one is set as Master but in the second one I have changed nothing and wired RS232 but it shows error saying not configured correctly or wiring incorrect. So , I was saying do we have to configure something in slave router as well for proper working.

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I'm not sure about your wiring, but here's the example.