Using an ili9341 display

Hardware
1

hi, i have a ili9341 display her that I d like to use to test zynthian can someone tell me how to setup please?
the display is this one



the screen light but I don t know how to set it in the webconf and what I have to do to make it working, I m totally noob with rasbian
thanks in advance
2

Hi, maybe this helps:

3

I already seen this after this post but that didn’t t worked for me I really lack in knowledge :frowning:

4

you can start by telling what you have done so far. then it will be easier to give you advices

5

I connected the display as described in th link I gave, and tried the things that are telling too, but I must admit that I don t know really what I was doing :frowning:
I use a raspberry pi 3B, I don t know how to set the screen in the web configurator and don t know if I have to instal drivers or something?

6

The link you sent is not exactly suitable for Zynthian (I’ve made the same mistake when I was configuring my screen). Try keeping the same connection as described in your link, but reconnect BL from pin 12 to pin 32(gpio-12). Then you can try compiling the dtoverlay (something like a driver) from the topic @le51 referenced. First grab the source file. ssh into your pi, execute command nano mytft.dts this will open text editor, paste the contents of the file you grabbed and press ctrl + O (save) and then ctrl + X (exit). Now you can compile your dtoverlay using following command

sudo dtc -@ -I dts -O dtb -o /boot/overlays/mytft.dtbo mytft.dts

Then go to webconf, and set up the screen as shown in this post.

7

Thanks a lot I ll try this tonight!!!

8

I know this is from quite awhile ago, but did you have any luck with the last suggestion?

I’m trying to get a similar ili9341 tft display working and have spent more time than I’d like to admit trying different things with no luck! (including the custom overlay mentioned above). Using RaspberryPi OS Bullseye, I was able to get something on my tft screen using the rpi-display overlay, so I think my SPI connections are OK. But that doesn’t seem to work on Zynthian.

Anyone have any ideas?

More information:

I have the display working fine in plain Raspbian Buster – both console and desktop. In Buster, frame buffer 1 is created in /dev/fb1, but in Zynthian, /dev/fb1 is not created making me believe there might be some issue with the rpi-display overlay process?

Finally:

After many, many, many trials and almost as many errors, I finally edited and compiled the rpi-display.dts file that worked for me on Buster, changing the backlight from gpio 18 to gpio 12. Pin 18 was causing a conflict. After using a custom device (as described in this thread) with the new overlay, it worked!

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9

Well, not actually finally, I found out. Turns out that I didn’t need a new DTOverlay to get Zynthian up and running with my display. Adding “backlight=12” to the standard “rip display 2.8” configuration in Web Config, the UI loaded and the display worked fine.

BUT, I have one other issue I haven’t been able to solve. My display has a pull-up resistor on the backlight control pin. So, with the backlight pin not connected, the display works just fine. However, if I connect the backlight pin on the display to GPIO 12 on the RPi, the display goes dark implying that GPIO 12 is grounded. I’ve spent quite a bit of time trying to figure this out, with no luck!

Does anyone have any ideas about this?

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