LFCLK init problem

[DanisXZ]

Hi,

Out of testing large number of boards, observed one board is not working. When tried to debug, found this weird problem. Code is stuck in LFCLK init part.

main() {

lfclk_config();

}

void lfclk_config(void)
{
if (!nrf_drv_clock_init_check())
{
ret_code_t err_code = nrf_drv_clock_init();
APP_ERROR_CHECK(err_code);
}

if (!nrf_drv_clock_lfclk_is_running())
{
nrf_drv_clock_lfclk_request(NULL);
while(!nrf_drv_clock_lfclk_is_running())   // Line 10
{
idle_state_handle(); //Stuck here
}
}
}

Please find the following observations.

1. It works in debugging mode, does not work in standalone mode
2. LF clk source is external crystal
3. changed line 10, while(!nrf_drv_clock_lfclk_is_running()) to  while(NRF_CLOCK->LFCLKSTAT & 0x10000 == 0)  --> It worked
4. changed line 10, while(!nrf_drv_clock_lfclk_is_running()) to  while((NRF_CLOCK->LFCLKSTAT & 0x10000) == 0)  --> added braces, not working  
5. Problem exist in all optimization levels
6. checked with the following code. It stops working when braces are added as mentioned in point 4.

   nrf_drv_clock_init();
NRF_CLOCK->INTENSET = 2;
NRF_CLOCK->LFCLKSRC = 1;
NRF_CLOCK->EVENTS_LFCLKSTARTED = 0;

   NRF_CLOCK->TASKS_LFCLKSTART = 1;
while((NRF_CLOCK->LFCLKSTAT & 0x10000) == 0) //does not work with braces
{
idle_state_handle();
}

Any suggestion how to find out the root cause for the issue ?

[Kazi Afroza Sultana]

Hello,

Since only one board is not working; could you please try to change the external crystal for that board?

Thanks. 

Best Regards,

Kazi Afroza Sultana