Custom GPIO pin in Overlay file

[sathishraj]

I want to add a simple GPIO pin that act as output pin, in the peripheral_uart example .

in main.c

#include <drivers/gpio.h>

//#define GPIO0_LABEL DT_PROP(DT_NODELABEL(gpiocus0), label)

//#define GPIO0_STATUS DT_PROP(DT_NODELABEL(gpiocus0), status)

//#define PIN 10

//#define FLAGS 0

#define LEDBLUE_NODE DT_ALIAS(ledblue)

#define LEDBLUE      DT_GPIO_LABEL(LEDBLUE_NODE, gpios)

#define LEDBLUEPIN   DT_GPIO_PIN(LEDBLUE_NODE, gpios)

#define FLAGS        DT_GPIO_FLAGS(LEDBLUE_NODE, gpios)

added these line main()

{

 const struct device *dev;

    bool led_is_on = true;

    int ret;

   

    dev = device_get_binding(LEDBLUE);

    ret = gpio_pin_configure(dev, LEDBLUEPIN, GPIO_OUTPUT_ACTIVE | FLAGS);

    for (;;) {

        dk_set_led(RUN_STATUS_LED, (++blink_status) % 2);

        k_sleep(K_MSEC(RUN_LED_BLINK_INTERVAL));

         gpio_pin_set(dev, LEDBLUEPIN, 1);//(dev, LEDBLUEPIN, (int)led_is_on);

        led_is_on = !led_is_on;

        k_msleep(500);

                printk("hello2");

    }

I could not see any change in the GPIO pin.

I have tried followed the below links,

https://devzone.nordicsemi.com/f/nordic-q-a/72618/extra-gpios-in-board-overlay-for-nrf9160dk

https://stackoverflow.com/questions/69873229/how-to-add-constants-to-a-devicetree-overlay

So, kindly show me any simple method to just turn on a GPIO and Read a pin from a GPIO by the way of OVERLAY FILE.

[Jared]

Hi,

Are you using a development kit?

How are you checking if the signal is toggling? Do you measure the voltage directly on the pin?

Can you try to use GPIO_ACTIVE_LOW instead 0 in the project config.

regards

Jared 

[sathishraj]

Thank you very much...its working.  DT_ALIAS setting configured properly; then starts working. In Prj.conf , i have only this line  CONFIG_GPIO=y.

when writing a pin, 

    dev = device_get_binding(LED1);

    if (dev == NULL) {

        return;

    }

    ret = gpio_pin_configure(dev, PIN1, GPIO_OUTPUT_ACTIVE | FLAGS);

    if (ret < 0) {

        return;

    }

gpio_pin_set(dev, PIN1, 1);// when PIN=1; in the output voltage we get 0V, when PIN=0; we get 3.3Voltage in that

And also in reading a pin; 

    dev = device_get_binding(BUTT);

    if (dev == NULL) {

        return;

    }

ret = gpio_pin_configure(dev, PIN2, GPIO_INPUT| FLAGS);

static int8_t readPinVal=0;

readPinVal = gpio_pin_get(dev, PIN2); // when PIN2 =0; We get readPinVal =1; and vice versa.

I do want in in reversal. How to do that.

HOW TO USE THIS:

arduino_header: connector {

        compatible = "arduino-header-r3";

        #gpio-cells = <2>;

        gpio-map-mask = <0xffffffff 0xffffffc0>;

        gpio-map-pass-thru = <0 0x3f>;

        gpio-map = <0 0 &gpio0 3 0>,    /* A0 */

               <1 0 &gpio0 4 0>,    /* A1 */

               <2 0 &gpio0 28 0>,   /* A2 */

in the overlay file, in-order to act this pin as input or output.