zephyr software timer cannot trigger periodically.

RE: zephyr software timer cannot trigger periodically.

hjq — Tue, 16 Dec 2025 01:11:30 GMT

To be honest, I also want to upgrade to the new NCS version. However, I need to use ANT+, and for now I can only develop it in version 2.9.2. I'm looking forward to future updates from Garmin.

RE: zephyr software timer cannot trigger periodically.

Benjamin — Mon, 15 Dec 2025 20:15:29 GMT

That is good new! There was a bug in drivers/timer/nrf_grtc_timer.c, and it looks like this PR fixed the issue you are seeing. You may want to upgrade to a newer NCS version, or keep your current solution if it is working for you.

Regards,
Benjamin

RE: zephyr software timer cannot trigger periodically.

hjq — Mon, 08 Dec 2025 06:40:37 GMT

HI，

This duration might not be exactly 12 hours; it could be shorter. However, I haven't attempted it yet.

Thaks for the heads up,I tried to clear the GRTC register before the soft reset, and this problem no longer occurred.

So, can you roughly figure out what caused this problem of mine?

Is there any other better way to solve the problem during the program initialization?

bool app_device_researt(void) {
  nrf_grtc_task_trigger(NRF_GRTC, NRF_GRTC_TASK_STOP);
  nrf_grtc_task_trigger(NRF_GRTC, NRF_GRTC_TASK_CLEAR);
  NVIC_SystemReset();
  return true;
}

RE: zephyr software timer cannot trigger periodically.

Benjamin — Fri, 31 Oct 2025 14:21:46 GMT

Thanks. Do you have to wait exactly 12 hours? Try doing the soft reset sooner to see if it changes anything. Also, a soft reset doesn’t clear the GRTC register, but a watchdog timer reset does. Can you check if the issue still occurs after a watchdog timer reset? It would also be helpful if you print the timer values right before and after the resets.

RE: zephyr software timer cannot trigger periodically.

hjq — Fri, 31 Oct 2025 01:43:26 GMT

Hi，

Thank you very much. This problem has been bothering us for a long time.

Yes, you are absolutely correct. After this issue occurred, I was unable to fix it by restarting or refreshing the firmware. However, I tried powering off the device, using the recover board, and performing DFU upgrade. All these operations were able to fix the problem. I also attempted to reproduce it on the DK, but it didn't work.

RE: zephyr software timer cannot trigger periodically.

Benjamin — Thu, 30 Oct 2025 13:54:19 GMT

I’d like to forward this to someone who can provide a more detailed answer. Please confirm that I’ve understood your issue correctly.

You’re using a custom board with the nRF54L05. After the device has been running for about 12 hours and performs a sys_reboot(), the timer no longer fires as expected. When you call k_timer_remaining_get() after the issue occurs, it returns an abnormally large remaining time.

After this issue has occurred, can you fix it by power cycling or reflashing the firmware?
Also, have you been able to reproduce this issue on a DK (nrf54l15dk/nrf54l05)?

Regards,
Benjamin

RE: zephyr software timer cannot trigger periodically.

hjq — Thu, 30 Oct 2025 10:10:03 GMT

yes，The remaining time is decreasing, and it decreases by 1 second each time.

RE: zephyr software timer cannot trigger periodically.

Benjamin — Thu, 30 Oct 2025 09:44:06 GMT

Thanks, and do you see this remaining time decrease?

RE: zephyr software timer cannot trigger periodically.

hjq — Thu, 30 Oct 2025 09:25:24 GMT

Hi,

In the main function, I use the k_timer_remaining_get function to query the next expiration time of the clock once every 1 second.

The log printing time is as follows:

RE: zephyr software timer cannot trigger periodically.

Benjamin — Thu, 30 Oct 2025 09:18:11 GMT

Hi,
Do you have any application logs that demonstrate this issue?

Regards,
Benjamin

RE: zephyr software timer cannot trigger periodically.

hjq — Tue, 28 Oct 2025 01:17:18 GMT

Hi,

I apologize for providing incorrect information. After further experiments, it was found that the equipment in the experimental group still had the same problem.

RE: zephyr software timer cannot trigger periodically.

Benjamin — Mon, 27 Oct 2025 13:37:58 GMT

Hi,
Sorry for the delay. That’s interesting, but I’m not sure I fully understand the differences. So in one group, the timer worked as expected? Could you share a clear list of what you did differently between the devices that failed and those that didn’t?

Regards,
Benjamin

RE: zephyr software timer cannot trigger periodically.

hjq — Thu, 23 Oct 2025 02:24:20 GMT

HI,

Yesterday, I conducted a control experiment. Each group consisted of 5 devices. The periodic timer was initialized and started at the beginning of the main function. Then, a comparison was made with the previous usage method. After one day, all the devices in the control group failed, while all the devices in the experimental group were normal. Could this be related to the channel allocation of GRTC?

RE: zephyr software timer cannot trigger periodically.

hjq — Wed, 22 Oct 2025 01:45:01 GMT

Hi,

This problem was discovered during the aging test of the produced equipment. After being left overnight, it was found that 90% of the equipment was unable to operate normally the next day.

This problem will 90% likely occur if left overnight.

The equipment was still functioning normally before the sys_reboot (SYS_REBOOT_COLD) operation. During the product development stage, we accidentally discovered that the timer seemed to have a problem of not starting. Later, we no longer used it. In the subsequent development process, we had to send task events precisely at the exact time, and then we could use it again. As expected, this problem occurred again.

Finally, I would like to add that the SDK version I used was 2.9.2. I also employed ANT and BLE.

Here is my expiration function:

void delay_timer_handler(struct k_timer *timer) {
  static uint8_t cnt = 0;
  // printk("1\n");
  cnt++;
  if (cnt >= 100) {
    cnt = 0;
    k_event_post(&light_event, LIGHT_TIME_1S_EVENT | LIGHT_TIME_EVENT);
  } else
    k_event_post(&light_event, LIGHT_TIME_EVENT);
}

RE: zephyr software timer cannot trigger periodically.

Benjamin — Tue, 21 Oct 2025 11:04:48 GMT

Hi,

I have some follow up questions before we proceed:

[quote user=""]there was a probability[/quote]

What would you estimate this probability to be? How many times have you encountered this issue?

Does this happen only when your system has run for 12h + and then right after sys_reboot(SYS_REBOOT_COLD) ?

Have you encountered the issue using the timer with a different period?

What is going on in your expiration function?

Best regards,
Benjamin