Fake Nextion display ?

[RogerClark]

I bought a 2.4 inch Nextion display from a eBay vendor, and it seems to be slowly going wrong, and I'm trying to work out if its a clever fake..

The display claims to be a Nextion NX3224T024_011 but does not have the ITead logo on it, and the PCB layout does not match the official photo

https://nextion.itead.cc/resources/datasheets/nx3224t024_011/


When I first got it, and tried to upload via micro SD, it failed to update, so I connected it via a USB to Serial adaptor and I was able to upload data, and it seemed to work OK.

Subsequently, when I tried to upload again, the Nextion editor would no longer recognise the board, even though it worked when I sent it commands data.
My guess is that the Serial Tx line stopped working, but the Serial Rx was still working.

Since I couldn't update via serial, I tried a few old micro SD cards and finally found one it would recognise and was able to upload again a few times.

But its now stopped receiving data via serial. 


Hence I'm now trying to figure out if this is an authentic Nextion or a clone / fake.  The vendor (in China) insists its a "different time" of board. I don't know if they mean an old board, or a different "type" of board.

In terms of what seems to have failed, it appears to have either diodes or resistors between the Serial Rx and Tx inputs and GND.
But I measured these components and they read less than 1k. One of them reads slightly differently front to back, but that could be the STM32F030 I'm partially measuring, as its impractical to remove those components as they are SMD.

I have a feeling that these may be protection diodes of some kind, and they may have been damaged somehow. But I can't see how that could have happened.

BTW. I can't find a schematic for a Nextion display, despite the official ones appearing to have the open source hardware logo on them ;-)

[donotdespisethesnake]

BTW. I can't find a schematic for a Nextion display, despite the official ones appearing to have the open source hardware logo on them ;-)

That is just the Itead logo I think? Any similarity to the OSH gear logo is probably coincidental.

Anyway, Nextion is not Open Souce https://nextion.itead.cc/faqs/

Your board could be a clone of a clone... IP just gets passed around China and each time people substitute cheaper components until finally it's just a space model.

[RogerClark]

Thanks

The serial Tx and Rx have now totally failed on the board, so I'm trying to get a refund, but so far they only offered me 25% of what I paid.

I'll probably have to write it off to experience, and perhaps salvage the TFT panel and touch screen and use with a separate MCU.

If I could be bothered I could remove the STM32F030 and replace with something a bit better, possibly a F103 or even a small STM32F4 but I doubt its worth the effort and risk of damaging the PCB by using my hot air rework tool