Driving the ili9488 LCD (4.0 inch cheap chinese clone)

[p a s h]

hello! i was trying to hook up a 3.5" display to my orange pi zero 2w, but when i try to use the DTS, all i get is black and white stripes. does anyone know a fix or what this even means? 

[robertoj]

It probably means that you are close to having it work.

75% of the effort (or good luck) results in the LCD displaying noise or bad image.

 

What model LCD?

Photos?

Confirm the wiring matches the default SPI terminals and the custom GPIO I included in the DTS.

Are you connecting the touch chip terminals?

LInux and armbian version? Downloaded or self compiled?

Run the tests I have shown in several of my LCD threads: ili9341, ili9488.

Edited August 4 by robertoj

[p a s h]

its an ili9488 3.5" cheap red SPI display, pretty much right after posting the comment i got it to output a garbled image, i did change the pins to match my pin connections. i was running orange pi branded debian, doing stuff on armbian doesn't work for some reason, im going to try to compile it myself. i completely removed touch from the DTS because i dont really need it. i am on orange pi zero 2w btw. for some reason i cant upload an image

[robertoj]

My DTS is for the Orange Pi Zero 3.

 

There's another thread that shows the correct GPIO wiring and DTS GPIO definitions for Orange Pi Zero 2w.

[p a s h]

ill go look in there then, thanks!

[p a s h]

hello again, i searched around and pretty much everything links back to this thread. this is the best result i could get on latest armbian, does anyone know what i can change? i think the problem is that the image is kinda shifted down and then goes back up? im pretty sure i need to change some kind of offset, but other than that im stumped

[robertoj]

Try a lower SPI frequency and use direct wires from the orange pi zero 2w to the LCD

 

There might be something in the panel-mipi-dbi-spi.bin firmware to improve the display of the received bytes, but first do these two improvements (first try the direct wires)

 

Opiz2w cases:

https://forum.armbian.com/topic/52880-orangepi-zero-2w-wrong-color-display-on-mpi3501/

https://forum.armbian.com/topic/44191-orangepi-zero-lts-ili9341-tft-lcd-and-later-orangepi-zero-3/page/2/

https://forum.armbian.com/topic/46824-orange-pi-zero-3-ili9486-tft-lcd/

 

Edited Wednesday at 05:34 PM by robertoj

[p a s h]

thanks! direct wiring has definitely changed something, i guess ill keep changing stuff and update if i get something
upd: the direct wiring has definitely made an improvement, but it still looks offset, i have no idea how to fix this, changing stuff in panel-timing just.. does stuff randomly, and i have no idea how to pick the right one. does anyone know the solution to this kind of weirdness?

this is the best i could get it:

 

Edited Wednesday at 08:25 PM by p a s h

[robertoj]

post the link of the online store where you bought your LCD.

 

Why do you describe your problem as "offset", if your problem is a big rectangle that covers 25% of your screen?

Edited Thursday at 09:13 AM by robertoj

[p a s h]

now that i think of it, i think you're right; the data being displayed is not offset its just straight up not displayed in some regions and wraps around for some reason. i bought the display here. its very likely resold from aliexpress.

[robertoj]

The online store link doesnt work

 

Did you try lowering the SPI frequency?

 

Are you using the panel-mipi-dbi-spi driver?

 

I have no idea about the timing parameters in the firmware bin file. Are you familiar with notro's python script that turns a txt into a firmware bin file?

 

There's a chance that your LCD is bad. Try buying an extra LCD.

 

Future note for when you succeed with the driver: X11 will not work. There's a driver issue. If you can compile MESA3D you might get the needed updated driver. I have been using wayland+labwc... and I am currently in the effort to add a wayland greeter for the display manager (lightdm or greetd). (search my threads)

Edited Thursday at 05:05 PM by robertoj

[p a s h]

oh so THAT'S why Xfce didnt launch, good to know. i did try lowering the SPI frequency but the result is pretty much the same. i am using the panel-mipi-dbi-spi driver, i will check the script later and see how it actually works. i am 100% sure the display is not defective, it works perfectly fine through tft_eSPI on an esp32, i will try getting an another unit and see if it changes anything.

[robertoj]

Hmmm ok Now I am out of ideas.

 

Are you using a downloaded armbian image? I have been using only self-compiled armbian images... (I need features of the latest linux-edge)

 

It also prevents some problems if you uninstall or disable plymouth (interferes with loading the firmware file).

[p a s h]

i am using a downloaded image, trying to compile armbian has been an awful experience, i guess ill keep trying different settings and see if anything changes

[laibsch]

  

10 hours ago, robertoj said:

The online store link doesnt work

 

 

worked fine for me.

 

9 hours ago, p a s h said:

trying to compile armbian has been an awful experience

 

sorry to hear that.  what specific issues did you run into?  It should be fairly straight-forward to compile armbian.

 

git clone https://github.com/armbian/build
cd build
./compile.sh

 

[robertoj]

Make sure to power the VCC and LED with 3.3v, not 5v 

[p a s h]

Quote

what specific issues did you run into?

ok so, i tried to replicate the issues i had but they just... didnt happen? everything just... works perfectly fine????? i have no idea if it was just that i was particularly unlucky or something, but i just compiled a working image fairly easily.
edit: nevermind, when i retried after a restart i got a

Failed to update binfmts [ update-binfmts --enable qemu-arm ]

error, googling yielded almost no information (host: fedora 42)

Quote

Make sure to power the VCC and LED with 3.3v, not 5v 

i did!

Quote

The online store link doesnt work

its a russian store, so it probably has a bunch of countries region blocked (for me it works, even through VPN)
 

Edited Friday at 11:33 AM by p a s h

[laibsch]

we need full logs of your compilation.  Run like "./compile.sh [...] SHARE_LOG=yes"

[robertoj]

Share your DTS, maybe you missed something

 

Run:

 

dmesg | grep -E 'spi|panel' and post the result

 

I already saw the online store... it is the same LCD that I use (I have both 3.5" and 4.0" and they work with the same DTS and bin file)

Edited Friday at 04:24 PM by robertoj

[robertoj]

Are you using the same GPIO wiring as I am?

 

Previously, I was using different GPIO for the chip select, and touch wasn't working... now with my current GPIO in my DTS, it works perfectly.

[p a s h]

Quote

we need full logs of your compilation.  Run like "./compile.sh [...] SHARE_LOG=yes"

 

here: https://paste.armbian.com/oyozunowab (running through docker on fedora 42 latest everything after a restart, the same issue happens on a fresh download too)

Quote

Share your DTS, maybe you missed something

Spoiler

/dts-v1/;
/plugin/;
/ {
    compatible = "allwinner,sun50i-h616";
    fragment@0 {
        target = <&spi1>;
        __overlay__ {
            status = "okay";
            cs-gpios = <&pio 7 5 0>; 
            panel: panel@0 {
                compatible = "panel-mipi-dbi-spi";
                reg = <0>;
                spi-max-frequency = <40000000>;
                width-mm=<79>;
                height-mm=<54>;
                reset-gpios = <&pio 8 6 0>;
                dc-gpios = <&pio 7 4 0>; 
                write-only;
                format = "b6x2g6x2r6x2";
                panel-timing {
                    hactive = <480>;
                    vactive = <320>;
                    hback-porch = <0>;
                    vback-porch = <0>;
                    clock-frequency = <0>;
                    hfront-porch = <0>;
                    hsync-len = <0>;
                    vfront-porch = <0>;
                    vsync-len = <0>;
                };
            };
        };
    };
};

Quote

dmesg | grep -E 'spi|panel

i dont have it available atm, i will include it as soon as i can get access to it, but last time i checked dmesg there was pretty much no errors

Quote

Are you using the same GPIO wiring as I am?

no, not really, i changed the pins for D/C and reset iirc