How to enter sleep mode in nRF9160?

[Yusuke]

I'm implementing a function which enters sleep mode and wakes up by interrupt like below.. 

void main(void)
{
        uart_wifi = device_get_binding("UART_1");
        uart_irq_rx_disable(uart_wifi);
        uart_irq_callback_set(uart_wifi, uart_cb); // Set UART interrupt callback
        uart_irq_rx_enable(uart_wifi);

	while (1) {
        printk("enter sleep\r\n");
        __WFI();
        printk("wake up\r\n");
	}
}

Is this correct way to enter sleep mode? Do you know any other better ways to do it?

In the nRF52 series case, it seems that you can use nrf_pwr_mgmt_run() function.

https://devzone.nordicsemi.com/f/nordic-q-a/34584/wfe-wfi-and-systemon-mode-differences

[Stian Røed Hafskjold]

In Zephyr, there is an idle thread that starts to execute when there are no other tasks. Please read more here: http://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/kernel/threads/system_threads.html

There's no need to enter sleep mode from the main thread. In fact you can return from the main thread if you don't do anything in the main thread.

If you specifically want to enter sleep mode from the main thread, please have a look here: https://docs.zephyrproject.org/latest/reference/kernel/other/cpu_idle.html?highlight=idle%20thread#

[Yusuke]

Thank you for your reply. I'm new to zenphyr. Could you tell me how to use the idle thread or give me any example code?

[Stian Røed Hafskjold]

The idle thread is already implemented in the zephyr code. The example code is in the nRF connect SDK: http://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/index.html

[rkguy]

Just for clarity, are you saying that the examinex enter idle thread when we are not doing anything, e.g. eDRX mode in the asset tracker example is using idle thread? Also your first link is broken in your original reply and in can not find the documentation for idle thread in your last link 

[Steven]

Updated link: https://docs.zephyrproject.org/1.11.0/kernel/threads/system_threads.html