THVD2412: RS485 Tranceiver

Which pins are still connected to the bus? Do both transmitting and receiving work?

Now only A and B are connected to the bus. Both transmitting and receiving worked.

Dhanya,

Do you have scopeshots of what you're seeing?

Do you have a schematic we can review?

-Bobby

Hi Bobby, Attached the design screen shot above.

Regards,

Dhanya

And what is connected to J4? How exactly are you testing the communication?

Hi, RS485 adaptor is connecting between J4 and PC.

Hi Dhanya,

Can you get scopeshots of the node you aren't expecting feedback from? 

Are the two boards communicating with each other using the same circuit (both are full duplex set up)? If the other board is using a half duplex set up and connects back to your original full duplex board, then you could get a mirror of the data with some prop delay. 

-Bobby

Hi Bobby, Will try to get the scope shots.

The board worked in full duplex setup.

Is it possible to confirm if there any internal short happened between A/B and Y/Z if we are using it in half duplex mode(using only A/B).

Regards,

Dhanya

You could disconnect the device from the cable side and measure the A/B and Y/Z pins on an o-scope and see if the mirrored data showed up there. If it does then the issue is local to the board/device. If it doesn't then it's likely from one of the connected boards.

-Bobby