Changed from basic 3.2 to enhanced 3.5 and display no update fields

Hi all,

My project is a bore pump controller with flow rate, pressure etc and touch screen to control the pump and change parameters. I had a 2 line LCD and upgraded to Nextion 3.2" touch.

I have been using a basic 3.2" Nextion display for some time and it has been working well. I needed another one to continue developing (as I left my prototype unit attached to the bore pump on the farm) so decided to purchase an enhanced 3.5" directly from Itead. From what I can find online, it should behave exactly the same, however it refuses to respond to any commands I send it from my (Microchip PIC) controller.

Is there some difference between the two of which I am unaware?

I connected to a PC and successfully uploaded my design, so I know at a basic level the display is functional. It powers up and shows my main page ok.

I hook up putty and I can see the commands coming from my controller on the Putty screen. I don’t see any response back on the Tx line (scope) at all if I touch the screen. I even modified my code just to send screen reset every 2 seconds but it doesn’t even reset. Baud rate is default at 9600.

I hesitate to try to log a support call given all the negative comments here about that process, so hopefully somebody can give me a clue as to what to try.


Since it uploads and starts the screen seems to be okay. Could it be that you haven‘t configures the screen to the right baudrate?

Kind regards,

Also verify the tx and rx lines have continuity between the Nextion and the pcb.
And the Nextion tx is connected to pcb rx.

Thanks everybody. I borrowed a display the same type and Voila!.. same issue. It seems that I had swapped Tx and Rx on the board and I must have put a crossover in the cable and forgotten.

Appreciate everybody’s response.

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