`nrf_pwr_mgmt_run` returns immediately, and the return value is 0.

RE: `nrf_pwr_mgmt_run` returns immediately, and the return value is 0.

Susheel Nuguru — Mon, 27 Apr 2026 18:24:33 GMT

FreeRTOS provides vApplicationIdleHook to give you safe time to go to low power modes? You can call nrf_pwr_mgmt_run in that instead.

Or as mentioned in this just before calling nrf_pwr_mgmt_run, for debug reasons, print to see any pending IRQs keeping the system awake.

for (int i = 0; i < 32; i++) {
    if (NVIC_GetPendingIRQ(i)) {
        printk("IRQ %d is pending\n", i);
    }
}

RE: `nrf_pwr_mgmt_run` returns immediately, and the return value is 0.

Jack.Hong — Mon, 27 Apr 2026 08:10:53 GMT

I hope you understand why I need to use the nRF5 SDK.

I used UART for logging and other one, so I add unint UARTE and TWI before nrf_pwr_mgmt_run.

But still immediately return from nrf_pwr_mgmt_run .

RE: `nrf_pwr_mgmt_run` returns immediately, and the return value is 0.

Turbo J — Mon, 27 Apr 2026 07:30:55 GMT

Note that support for this SDK stopped quite a while ago, you want to upgrade to NCS SDK.

What logging method do you use? Logging UART may still be active and would keep the MCU core from sleeping.

Also check if nrf_pwr_mgmt_run actually knows how to skip FPU exceptions (see other sample code how). Don't remember the RTOS code well enough here, but pending FPU exceptions will keep the core running.