How to use DCX SPI configuration in Zephyr !?

[Esmaeill]

I successful use SPI by Zepher, I want communication with LCD Display but cant use SPI Data/Command option GPIO for config LCD !

zephyr,gc9a01.yaml

description: My spi device binding
compatible: "zephyr,gc9a01"
include: spi-device.yaml

.overlay

&spi1 {
    cs-gpios = <&gpio0 29 GPIO_ACTIVE_LOW>;
    gc9a01:gc9a01@0 {
        compatible = "zephyr,gc9a01";
        reg = < 0 >;
        spi-max-frequency=<30000000>;
        label = "gc9a01";
    };
};

send data:

spi_write_dt(&gc9a01,&spi_buffer_tx_set);

I read the datasheet of nrf52840 & i found D/CX SPI configuration!

How i must use that in Zephyr and how must i config GPIO for that??

[Øyvind]

Hello, 

I'm not familiar with the gc9a01 display, as this seems not be a part of the Zephyr environment. This means that there is no driver for this display. A quick Google search did bring me to the ZSWatch, which is a open-source watch running Zephyr and the gc9a01 display: https://github.com/jakkra/ZSWatch

Kind regards,
Øyvind

[Esmaeill]

Thanks, it helped a lot.

in that sample, for control D/C pin of LCD Was used normal GPIO set/reset fanctions.

Since the related functions are not implemented, I think that using register values can help. Something similar to this:

// D/Cx Control
NRF_SPIM1->DCXCNT=0; //0x0-0xf
NRF_SPIM1->PSELDCX=(4<<0)|(0<<5)|(0<<31);//P0.4 Connect

But in the first attempt, the system restarts!!

Thanks for the help, I will probably look into this more in the future.

[Øyvind]

Happy to help! 

Don't forget to look at our nrfx_spim library, and the nrfx_spim_xfer_dcx() function

Kind regards, 
Øyvind

[Esmaeill]

Thanks .
It is possible SPI zephyr library automation control D/Cx pin like CS? or not implemented yet ?

[Øyvind]

You're welcome!

Esmaeill said:

It is possible SPI zephyr library automation control D/Cx pin like CS? or not implemented yet ?

Could not find anything in our SDK. Did a quick search on the Zephyr Discord server, and found this thread discussing similar topic..