ST7789 display connected to a nRF5340DK board

RE: ST7789 display connected to a nRF5340DK board

Naeem Maroof — Wed, 31 Jul 2024 14:24:36 GMT

Hi Leo,

that seems to be specific issue/concern with the display,

nonetheless, yes, you can control it through a gpio pin and set the pin to high in the code.

RE: ST7789 display connected to a nRF5340DK board

lcj — Sat, 27 Jul 2024 20:31:58 GMT

I don't see backlight referenced in it or even bl. I can connect it to 3.3 and have it on all the time but is there a way I can control it turning on and off from code?

RE: ST7789 display connected to a nRF5340DK board

helsing — Thu, 27 Jun 2024 13:30:12 GMT

[quote user="lcj"]How does the backlight (BL) connect to the board and where is it referenced in the overlay?[/quote]

It looks like the backlight is not refernced in the overlay.

What you could do is to choose a free pin and implement the control of this, either in your application or you could modify the driver.

I also searched the datasheet for 'backlight' and found this:

Perhaps it is possible to turn on or dim the backlight from the SPI interface?

I also noticed there is an overlay named st7789v_waveshare_240x240.overlay in the SDK. Have you tried that one?

RE: ST7789 display connected to a nRF5340DK board

lcj — Tue, 25 Jun 2024 11:18:29 GMT

How does the backlight (BL) connect to the board and where is it referenced in the overlay?

RE: ST7789 display connected to a nRF5340DK board

WesC — Thu, 21 Sep 2023 11:35:09 GMT

So if you want to use the shield you should be able to add the CMAKE argument in the build configuration in VSC. so select "ADD Argument" under the extra cmake argument option. in that field type

-DSHIELD=st7789v_tl019fqv01

this should add the shield in the build and you can see that in the build/zephyr folder with the Zephyr.dts file.

if you want to just use the overlay like above then you add the SPI features above the child node definition for the ST7789. you will also need to define the pin_cntrl for those pins. something like this:

&spi1 {
	compatible = "nordic,nrf-spim";
	status = "okay";
	pinctrl-0 = <&spi_master_default>;
	pinctrl-1 = <&spi_master_sleep>;
	cs-gpios = <&gpio0 11 GPIO_ACTIVE_LOW>;
	st7789v_st7789v_tl019fqv01: st7789v@0 {
	compatible = "sitronix,st7789v";
	spi-max-frequency = < 0x1312d00 >;
	reg = < 0x0 >;
	cmd-data-gpios = < &arduino_header 0xf 0x1 >;
	reset-gpios = < &arduino_header 0xe 0x1 >;
	width = < 0x140 >;
	height = < 0xaa >;
	x-offset = < 0x0 >;
	y-offset = < 0x23 >;
	vcom = < 0x2b >;
	gctrl = < 0x35 >;
	vrhs = < 0xf >;
	vdvs = < 0x20 >;
	mdac = < 0x60 >;
	gamma = < 0x1 >;
	colmod = < 0x55 >;
	lcm = < 0x2c >;
	porch-param = [ 0C 0C 00 33 33 ];
	cmd2en-param = [ 5A 69 02 01 ];
	pwctrl1-param = [ 52 A1 ];
	pvgam-param = [ D0 00 02 07 0B 1A 31 54 40 29 12 12 12 17 ];
	nvgam-param = [ D0 00 02 07 05 15 2D 44 44 1C 18 16 1C 1D ];
	ram-param = [ 00 F8 ];
	rgb-param = [ CD 08 14 ];
	};
}

&pinctrl {
	spi_master_default: spi_master_default {
		group1 {
			psels = <NRF_PSEL(SPIM_SCK, 0, 6)>,
					<NRF_PSEL(SPIM_MOSI, 0, 7)>,
					<NRF_PSEL(SPIM_MISO, 0, 25)>;
		};
	};

	spi_master_sleep: spi_master_sleep {
		group1 {
			psels = <NRF_PSEL(SPIM_SCK, 0, 6)>,
					<NRF_PSEL(SPIM_MOSI, 0, 7)>,
					<NRF_PSEL(SPIM_MISO, 0, 25)>;
			low-power-enable;
		};
	};
	};

RE: ST7789 display connected to a nRF5340DK board

lcj — Thu, 21 Sep 2023 11:14:25 GMT

So create an overlay file for the board and copy the st7789, correct? Where do I connect the wires from the display to the 5340dk?

I see these two display settings in the pinetime dts and the shield. They are both under a spi, is there some way I should set this up for the nrf5340dk?

&arduino_spi {

status = "okay";

cs-gpios = <&arduino_header 16 GPIO_ACTIVE_LOW>; /* D10 */

st7789v_st7789v_waveshare_240x240: st7789v@0 {

compatible = "sitronix,st7789v";

spi-max-frequency = <20000000>;

reg = <0>;

cmd-data-gpios = <&arduino_header 15 GPIO_ACTIVE_LOW>; /* D9 */

reset-gpios = <&arduino_header 14 GPIO_ACTIVE_LOW>; /* D8 */

width = <240>;

height = <240>;

x-offset = <0>;

y-offset = <0>;

vcom = <0x19>;

gctrl = <0x35>;

vrhs = <0x12>;

vdvs = <0x20>;

mdac = <0x00>;

gamma = <0x01>;

colmod = <0x05>;

lcm = <0x2c>;

porch-param = [0c 0c 00 33 33];

cmd2en-param = [5a 69 02 01];

pwctrl1-param = [a4 a1];

pvgam-param = [D0 04 0D 11 13 2B 3F 54 4C 18 0D 0B 1F 23];

nvgam-param = [D0 04 0C 11 13 2C 3F 44 51 2F 1F 1F 20 23];

ram-param = [00 F0];

rgb-param = [CD 08 14];

};

&spi1 {

/* Sitronix ST7789V LCD */

st7789v: st7789v@1 {

compatible = "sitronix,st7789v";

reg = <1>;

spi-max-frequency = <8000000>; /* 8MHz */

cmd-data-gpios = <&gpio0 18 GPIO_ACTIVE_LOW>; /* DET */

reset-gpios = <&gpio0 26 GPIO_ACTIVE_LOW>; /* RESX reset */

width = <240>;

height = <240>;

x-offset = <0>;

y-offset = <0>;

vcom = <0x19>;

gctrl = <0x35>;

vrhs = <0x12>;

vdvs = <0x20>;

mdac = <0x00>;

gamma = <0x01>;

colmod = <0x05>;

lcm = <0x2c>;

porch-param = [0c 0c 00 33 33];

cmd2en-param = [5a 69 02 01];

pwctrl1-param = [a4 a1];

pvgam-param = [D0 04 0D 11 13 2B 3F 54 4C 18 0D 0B 1F 23];

nvgam-param = [D0 04 0C 11 13 2C 3F 44 51 2F 1F 1F 20 23];

ram-param = [00 F0];

rgb-param = [CD 08 14];

};

RE: ST7789 display connected to a nRF5340DK board

lcj — Thu, 21 Sep 2023 10:40:34 GMT

Shields are confusing me a little.

I see &arduino_spi in the st7789v_st7789v_waveshare_240x240 file does that mean I need to create a reference for the nrf5340dk_nrf5430_cpuapp? Is that what is meant by "boards must also provide a configuration matching their supported connectors." Does that mean I need to create a specific one for the nrf5340?

I am use to changing things in a local overlay but not really changing the command line (since I'm using the nrf connect for visual studio adding), so I think I would use the kconfig option for actviation.

Is all of this an alternative to creating an overlay file?

RE: ST7789 display connected to a nRF5340DK board

khelmutlord — Wed, 20 Sep 2023 13:54:44 GMT

To tag on, there is a “shield” overlay file for this display: https://docs.zephyrproject.org/latest/boards/shields/st7789v_generic/doc/index.html

more info on shields:

docs.zephyrproject.org/.../shields.html

RE: ST7789 display connected to a nRF5340DK board

WesC — Wed, 20 Sep 2023 13:48:51 GMT

The ST7789 has many node specific properties outside the SPI interface

https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/build/dts/api/bindings/display/sitronix,st7789v.html#std-dtcompatible-sitronix-st7789v

you can look at the Pinetime devkit0 with the DTS for a reference. there is a node specific to the ST7789 and it is part of the chosen node as zephyr,display. you can mimic that in an overlay. you can find the dts here C:\ncs\v2.4.2\zephyr\boards\arm\pinetime_devkit0