Get timer count without stopping timer

RE: Get timer count without stopping timer

Edvin — Tue, 17 Mar 2020 07:52:46 GMT

Yes. That is probably the reason why it stopped. You can use another CC to capture the register.

BR,

Edvin

RE: Get timer count without stopping timer

Jose Cazarin — Mon, 16 Mar 2020 14:52:23 GMT

Thank you!
So, I kept searching in the forum and I found this topic:

https://devzone.nordicsemi.com/f/nordic-q-a/2173/capture-timer-value

Check Nikita's answer:

"You are already using CC[0] register for COMPARE0 event interrupt, so if you want to read current timer counter value you need to trigger CAPTURE task for another channel i.e.: NRF_TIMER2->TASKS_CAPTURE[1] = 1; u_sec = (NRF_TIMER2->CC[1]);"

This is exactly my situation. I'm using channel 0 (EVENT_COMPARE[0]) to generate the interruption. And it worked for me to just use another channel for capturing the timer count, like this:

_timer_base->TASKS_CAPTURE[1] = 1;
uint32_t counter = _timer_base->CC[1];

Since Nikita's answer if from 6 years ago, I just want to confirm: is that still valid?

And another question: is there any status register that I can read so I know if the timer is running or not? I just realized I need that information too

Thank you so much!

RE: Get timer count without stopping timer

Edvin — Mon, 16 Mar 2020 09:40:01 GMT

Hello,

By default, if the timer is set up correctly, taking one capture shouldn't stop the timer from running. I don't know how you set up the timer, or what timer you used.

Please have a look at the attached main.c file which is a slightly modified ble_app_hrs main.c file.

devzone.nordicsemi.com/.../main.c

Please have a look at test_timer_timeout_handler(). In addition, I added an app_timer instance with a timeout handler: test_timer_timeout_handler(), which will capture the NRF_TIMER3, and print the capture register. Please note that the app_timer and the timer that I capture are two different TIMER instances, working independently.

Best regards,

Edvin