NRF9160 Disable UART and RX pin into an interrupt pin

[Lamdev]

Hello everyone,

I'm working on a project with NRF9160 nRF Connect SDK v2.3.0.

In my project i use UART0 to exchange data and i disable the UART when is not use.

I need an interrupt to wake up my device when data come on the UART pin (TX/RX).

I have found different topic to disable and enable UART on runinng time. 

Now, when my uart is disable, i would like to convert RX pin into an interrupt pin which allow me to re-enable the UART to get data when interrupt occur.

Could you tell me if you have any advice about that ?

Best regards,

Lam

[Kazi Afroza Sultana]

Hello,

We think the problem lies where it is starting and stopping the UART. Can you check this (+) How can I enable and disable UART devices at run time on nRF9160? - Nordic Q&A - Nordic DevZone - Nordic DevZone (nordicsemi.com) case? You may need to check the RXTO event. 

Thanks.

BR

Kazi

[Lamdev]

Hello,

Thanks for your help,

I found a solution that was the following, if this can help someone.

Fullscreen

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

void button_pressed(const struct device *dev, struct gpio_callback *cb,

uint32_t pins)

{

int ret;

printk("Button pressed\r\n");

ret = gpio_pin_interrupt_configure(button.port,button.pin,GPIO_INT_DISABLE); //GPIO_INT_EDGE_BOTH

if (ret != 0) {

printk("Error disable INT\r\n");

return;

}

//restart_uart();

k_work_submit(&button_action_work);

//flag_interrupt = 1;

}

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

void button_pressed(const struct device *dev, struct gpio_callback *cb,
		    uint32_t pins)
{
	int ret;

	printk("Button pressed\r\n");

	ret = gpio_pin_interrupt_configure(button.port,button.pin,GPIO_INT_DISABLE);		//GPIO_INT_EDGE_BOTH
	if (ret != 0) {
		printk("Error disable INT\r\n");
		return;
	}
	
	//restart_uart();
	k_work_submit(&button_action_work);
	//flag_interrupt = 1;
}

Fullscreen

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

//gpio for UART interrupt definition
void configure_int_rx(void){
	int ret;

	printk("configure interrupt\r\n");

	if (!device_is_ready(button.port)) {
		printk("Error config INT 1\r\n");
		return;
	}
	
	ret = gpio_pin_configure(button.port,button.pin,GPIO_INPUT);
	if (ret != 0) {
		printk("Error config INT 2\r\n");
		return;
	}

	ret = gpio_pin_interrupt_configure(button.port,button.pin,GPIO_INT_EDGE_TO_ACTIVE);		//GPIO_INT_EDGE_BOTH
	if (ret != 0) {
		printk("Error config INT 3\r\n");
		return;
	}

	gpio_init_callback(&button_cb_data, button_pressed, BIT(button.pin));

	ret = gpio_add_callback(button.port, &button_cb_data);
	if (ret != 0) {
		printk("Error config INT 4\r\n");
		return;
	}

	printk("Config INT OK\r\n");
}

Fullscreen

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

void timer_disable_uart_work_fn(struct k_work *work)
{
	disable_uart();
    configure_int_rx();
}

Fullscreen

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

void process_work_timer_uart_disable(void){
	//scehdule a time to disable uart
    //cancel last schedule
    if(k_work_delayable_busy_get(&timer_disable_uart_work) != 0 ){
        k_work_cancel_delayable(&timer_disable_uart_work);
		while(k_work_delayable_busy_get(&timer_disable_uart_work) != 0 );	//wait until cancelation finnish
    }
    //enable new schedule
    k_work_schedule(&timer_disable_uart_work, K_SECONDS(WAIT_UART_DISABLE));
}

Fullscreen

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

/* other code line to use to work */
#define SWIN3_NODE	DT_ALIAS(swin3)
#if !DT_NODE_HAS_STATUS(SWIN3_NODE, okay)
#error "Unsupported board: SWIN3 devicetree alias is not defined"
#endif


static const struct gpio_dt_spec button = GPIO_DT_SPEC_GET_OR(SWIN3_NODE, gpios,0); 
static struct gpio_callback button_cb_data;

K_WORK_DEFINE(button_action_work, button_action_work_handler);
void button_action_work_handler(struct k_work *work) {
    //do_something_because_a_button_was_pressed();
	restart_uart();
}

static struct k_work_delayable timer_disable_uart_work;

k_work_init_delayable(&timer_disable_uart_work,timer_disable_uart_work_fn);

[Kazi Afroza Sultana]

Thanks for sharing the code. I am glad that you have fixed the issue.