Timers

[DPJONES]

Hi

I am would like to know how to setup *.overlay file for timer and find code for a simple timer interrupt using the nrf54l15.

Best Regards

David

[Kenneth]

Hello,

There are several options here, you can for instance use Zehyr kernel timers, this will then execute any code at given intervals:
https://docs.nordicsemi.com/bundle/ncs-1.9.2-dev1/page/zephyr/reference/kernel/timing/timers.html 
(used by: https://academy.nordicsemi.com/courses/nrf-connect-sdk-intermediate/lessons/lesson-1-zephyr-rtos-advanced/)
(example: https://github.com/NordicDeveloperAcademy/ncs-inter/blob/main/v2.9.0-v2.7.0/l1/l1_e1_sol/src/main.c) 

Another option, use the low level nrfx drivers:
https://github.com/NordicSemiconductor/nrfx 
(an old example for timer in specific using nrfx: https://github.com/too1/ncs-nrfx-timer-example/tree/master)

Kenneth

[DPJONES]

Hi Kenneth

Using the K_timer will there not be a problem with interrupts etc, as I want very accurate timings for an ADC sampling.

Best Regards

David

[Kenneth]

Hello,

It depends on what you mean by "accurate timing", how much deviation can you tolerate?

Kenneth

[DPJONES]

Hi

I have just started trying the ncs-nrfx-timer-example example I have problems, I am using a blinky example to start with and have just added the 2 lines of code below.

#include <nrfx_timer.h>

static const nrfx_timer_t my_timer = NRFX_TIMER_INSTANCE(1);

Error in terminal:

from C:/nordic/myApps/blinky_1/src/main.c:8:
C:/ncs/v2.9.0/modules/hal/nordic/nrfx/drivers/include/nrfx_timer.h:64:37: error: 'NRF_TIMER1' undeclared here (not in a function); did you mean 'NRF_TIMER10'?
64 | .p_reg = NRFX_CONCAT(NRF_, TIMER, id), \
| ^~~~
C:/ncs/v2.9.0/modules/hal/nordic/nrfx/drivers/nrfx_common.h:200:32: note: in definition of macro 'NRFX_CONCAT_2_'
200 | #define NRFX_CONCAT_2_(p1, p2) p1 ## p2

Can you please assist

David

[Kenneth]

Hello,

Maybe you can try:
https://github.com/kemegard/nrfx_timer_nrf54l15/tree/main/src/nrfx_timer/timer

Kenneth

[DPJONES]

Hi

Can you tell me what file has the peripheral declarations ie timer20

BRs

David

[Kenneth]

Hi David,

I skipped using the devicetree in this case, and simply updated:
https://github.com/kemegard/nrfx_timer_nrf54l15/blob/main/src/nrfx_timer/timer/main.c#L54 
Which is then used in:
https://github.com/kemegard/nrfx_timer_nrf54l15/blob/main/src/nrfx_timer/timer/main.c#L97 

Kenneth

[DPJONES]

Hi Kenneth

Where do find out what 20 is, where its allocated can it 320, I am very new to nordic so what is 20 referring too do you have 20 different timers in the peripherals.

Also this line is incorrect  nrfx_timer_init(&timer_inst, &config, timer_handler); and does not compile should be nrfx_timer_init(&timer_inst, &config, timer_event_handler);

BRs

David

[Kenneth]

https://docs.nordicsemi.com/bundle/ps_nrf54L15/page/timer.html#d1794e209 

Kenneth