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I made a custom board based on the RV1106 development board that I bought, the Luckfox Pico board, and modified the DTS of the official Luckfox SDK kernel to make it SFC, or SPI NAND booting. The only functions I use here are one I2C port and an LCD using the RGB interface.

Ethernet and other functions are honestly not necessary at all. When I look at the RGB interface pins with an oscilloscope, the waveforms of HSync and VSync are really found including DE pin and Data pins. However, there is no display on the LCD. It seems as if nothing is being received. So I set both Back Hporch and Back Vporch to 1 or 2, and configured the circuit and the kernel to match the ST7701 RGB panel.

Is there any way to do I can try?
LCD just displays black screen even I executes mode test tool.

DTS is like:


panel: panel {
compatible = "simple-panel";
backlight = <&backlight>;

reset-gpios = <&gpio0 RK_PA1 GPIO_ACTIVE_LOW>;
reset-delay-ms = <200>;
status = "okay";

bus-format = <MEDIA_BUS_FMT_RGB666_1X18>;
width-mm = <85>;
height-mm = <85>;

display-timings {
native-mode = <&timing0>;

timing0: timing0 {
clock-frequency = <3000000>;
hactive = <480>;
vactive = <640>;
hback-porch = <7>;
hfront-porch = <4>;
vback-porch = <3>;
vfront-porch = <2>;
hsync-len = <30>;
vsync-len = <60>;
hsync-active = <1>;
vsync-active = <1>;
de-active = <1>;
pixelclk-active = <1>;
};
};

port {
panel_in_rgb: endpoint {
remote-endpoint = <&rgb_out_panel>;
};
};
};

As I know, all panels that supports RGB interface can be integrated with existing RGB controller in MCU. but this is not working.
The LCD panel I choosen is `EP28060S-D` that is made in china, and I bought two panels from Ali-express. and both are not working.

I don't know chinese well, and I can not read it. but I did my best, Is there any way I can do?

Hello, because we can not adapt to all the screens on the market, we only provide suggestions for adapting other screens to luckfox pico. According to the information you provide, the screen cannot be lit up. There may be a lack of initialization of the screen (generally input initialization commands and data through the spi interface, and some screen initialization is implemented internally without external re-transmission commands). It is recommended that you consult the seller to obtain a sample program （stm32 or other platform）for determination.

Crocodile wrote: ↑2024-10-07 14:38 Hello, because we can not adapt to all the screens on the market, we only provide suggestions for adapting other screens to luckfox pico. According to the information you provide, the screen cannot be lit up. There may be a lack of initialization of the screen (generally input initialization commands and data through the spi interface, and some screen initialization is implemented internally without external re-transmission commands). It is recommended that you consult the seller to obtain a sample program （stm32 or other platform）for determination.

I've forgot the 3-wire SPI lane for LCD screen at last time.

So, I've added it and I ordered new board with modification. then, I'll ask about it again. thanks for reply.

I made new board with modification for LCD.
and it works now

but display timings in DTS is something different with hardware.
now, I need to modify it, thanks luckfox pico.

-- summary of my board:
1. designed based my Luckfox Pico Pro, RV1106G3 with 256M nand flash.
2. the major reason why I made custom board is to connect LCD through RGB interface that is not integrated in Luckfox Pico Pro.
3. all pins are not defined in Pico Pro, but all of them are working perfectly I expected.
4. I used RV1106G3 chip and NAND flash that was in Luckfox Pico Pro

thanks for luckfox team!