Timing bootloader

RE: Timing bootloader

bjorn-spockeli — Fri, 30 Aug 2019 11:39:04 GMT

You need to start the LFCLK so that the RTC has a clock source, i.e.

NRF_CLOCK->TASKS_HFCLKSTART = 1

while(!EVENTS_LFCLKSTARTED) {

// wait for LFCLK to start before starting RTC

}

RE: Timing bootloader

nrbrook — Fri, 30 Aug 2019 10:28:01 GMT

Thanks. In the bootloader I have this:

NRF_RTC2->TASKS_STOP = 1;
NRF_RTC2->TASKS_CLEAR = 1;
NRF_RTC2->PRESCALER = 0;
NRF_RTC2->TASKS_START = 1;

In the firmware I have this:

uint32_t count = NRF_RTC2->COUNTER;
uint32_t ms = count * 1000 / 32768;
NRF_RTC2->TASKS_STOP = 1;
NRF_RTC2->TASKS_CLEAR = 1;

However, ms is 0. Am I missing something?

RE: Timing bootloader

bjorn-spockeli — Fri, 30 Aug 2019 05:55:11 GMT

Hi Nick,

you can start a TIMER or RTC upon entering the bootloader. Since the bootloader branches to the applicatio, the TIMER or RTC will keep running and you can stop and read out the counter value in the application,

Best regards

Bjørn