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I have bought 2 tft lcd from this link: https://www.aliexpress.com/snapshot/8378816373.html?orderId=79915084513225&productId=32610719676

and after implementing the codes in here : RPi 2 and 3.95 TFT ili9488,

i manage them to work. But while one of them has standart colors and can render the images correctly the other one is kinda weird. Like the colors inverted somehow.

Since one of them works correctly and the other is weird i am thinking is a hardware problem but i want to try with inverted colors to check if i am right.

Can anyone point some directions to generate inverted color version of the output ? Usually it only requires to change a register but i dont know which of them...

the photo of the displays can be seen below: 1st one is ok, 2nd one is the problematic. here is the picture of the displays

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    Alibaba.... usually factory backdoor products. It is highly likley that the second one is damaged.(or did not pass QA in factory that is why you got it so cheep) PS White inverted is black. Is the white background black on the 2nd screen? NO! Send it back – Piotr Kula Nov 30 '16 at 15:41
  • The second screen looks like the red & blue channels have been swapped - it's awfully close to what my test screenshots of the desktop look like in BGR mode (view in RGB); the green channel might be missing though (I'd expect the leaves on the raspberry to look greener than they are there) – Dave Jones Dec 1 '16 at 10:09
  • During the search process i have contacted the seller. They accepted to send a new one (i dont know when though). if they dont ask for the broken screen back i think i can dismantle the pcb and the tft to check if there is a bad connection etc. I can write a post about it when the situation is settled. @ppumkin i know the reality about Alibaba but its still worth to try my chances since the same item costs a couple of times more where i live :/ – AeS Dec 2 '16 at 11:18
  • Hehehe. They so cheap they can send a "new" one without taking the old one back :D – Piotr Kula Dec 2 '16 at 11:19
  • :D Yeah you are right :D – AeS Dec 2 '16 at 11:21
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Sorry about digging up an old thread, but I came across it while looking for ideas on setting up my own ILI9488 on a Pi, and I've got a solid hunch on this problem.

I have not tried this, but have seen this issue with other display controllers (ILI9341). There is an BGR/RGB parameter which sets the colour order. It looks like you have a blue/red swap issue (red swapped for blue, green swapped for orange).

The options line of my ILI9341 setup has a bgr=1 parameter, which should set the colour order. I would suggest adding this to part 3 of RPi 2 and 3.95 TFT ili9488 where the options are added to

sudo nano /etc/modprobe.d/fbtft.conf

When I changed this to bgr=0 on my setup, I ended up with a very similar colour problem.

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