Regarding 2 wire RS485 to microcontroller RX pin.

[kiranhatti]

Dear All,


I have designed circuit to convert 2 wire RS485 to TTL (to microcontroller RX pin).

Note: I am going to implement only Reception. So there is only one Max485 ic.

Can you please let me know whether the microcontrller will receive the data?

Please find the attachment.

 

[FvM]

The circuit is basically correct. Naming of the RS485 lines may be different, you have to check if "Rx+" and "Rx-" is connected correctly. "Rx+" should be more positive in idle state.

 

[kiranhatti]

Thank u for your kind response.

Rx+ should be more positive in idle state means Rx+ should be pull down to ground right?

 

[FvM]

Everything is fine as it is. I see that naming line A as + and B as - is the standard way https://en.wikipedia.org/wiki/Rs-485