ant scan can't found any device

RE: ant scan can't found any device

nanty — Fri, 10 Jul 2026 01:57:38 GMT

Hi,

For now, I still config CONFIG_LOG_MODE_IMMEDIATE=y. But I don't do printfs in function antplus_evt_handler, all business operations are performed on another thread, and I am still receiving user feedback regarding this issue, and I can't reproduce it.

err_code = ant_cb_register(&antplus_evt_handler);
...

static void antplut_evt_post_event(async_param_t *param)
{
    ant_evt_t *p_ant_evt = (ant_evt_t *)param->args.u.ptr;
    if (p_ant_evt == NULL)
    {
        logs_e("p_ant_evt is NULL\r\n");
        return;
    }
    background_scanner_process(p_ant_evt);
    ant_evt_handler(p_ant_evt, NULL);
    for (uint8_t i = 0; ant_dev_list[i].disp_evt_handler != NULL; i++)
    {
        if (p_ant_evt->channel == ant_dev_list[i].channel_num)
        {
            ant_dev_list[i].disp_evt_handler(p_ant_evt);
        }
    }
    vh_free(p_ant_evt);
    p_ant_evt = NULL;
}

static void antplus_evt_handler(ant_evt_t *p_ant_evt)
{
    async_param_t param = {0};
    param.args.u.ptr = vh_malloc(0, sizeof(ant_evt_t));
    if (param.args.u.ptr == NULL)
    {
        return;
    }
    memcpy(param.args.u.ptr, p_ant_evt, sizeof(ant_evt_t));
    int ret = async_post(&async_ant, antplut_evt_post_event, &param, 0, false);
    if (ret)
    {
        vh_free(param.args.u.ptr);
        param.args.u.ptr = NULL;
    }
}

As you said, this problem is caused by other tasks taking over the time, It sounds like even if I configure CONFIG_LOG_MODE_IMMEDIATE=n, this problem might still be triggered, because there are other tasks in my project. Is this correct?

Also, I will close the printfs, and then observe the situation on the user side.

RE: ant scan can't found any device

sread — Thu, 09 Jul 2026 21:41:19 GMT

Hello, we've spent some time analyzing the provided sample with the stack and were able to isolate a condition where the stack can stall if it is delayed long enough by another task.

This is why CONFIG_LOG_MODE_IMMEDIATE Kconfig aggravates the issue, although there are scheduling context changes between sdk-nrf 2.9.2- and 3.2.4-aligned versions that also contribute. I still have not been able to reproduce this issue without CONFIG_LOG_MODE_IMMEDIATE. Please let me know if that does not match what you see.

We are arranging to release an updated ANT version for sdk-nrf 3.2.4. The process will take a few weeks.

RE: ant scan can't found any device

nanty — Wed, 08 Jul 2026 08:56:11 GMT

Any update?Thanks.

RE: ant scan can't found any device

nanty — Tue, 07 Jul 2026 05:39:15 GMT

Hi,

any update? Can we handle this issue this week?

RE: ant scan can't found any device

sread — Tue, 30 Jun 2026 22:11:37 GMT

Hi, root cause investigation is still pending. Support capacity is limited this week, so our response will be delayed until next week. We’ll update as soon as possible.

RE: ant scan can't found any device

nanty — Mon, 29 Jun 2026 02:42:01 GMT

Hi，

Any update?

RE: ant scan can't found any device

nanty — Fri, 26 Jun 2026 03:09:39 GMT

Hi,

I can't reproduce the issue when no printfs in antplus_evt_handler for now. The issue feedback from our user. I will try to reproduce it. The picture is the log I record in user.

RE: ant scan can't found any device

sread — Thu, 25 Jun 2026 23:47:48 GMT

We're still attempting to reproduce the issue on our side with v3.2.4 and the modified handler. If you're able to share a log from that build, even a short one showing the first occurrence, that would be helpful.

As far as the v2.9.2 differences, there were no changes to event dispatch in the ANT components. We are evaluating SDK dependencies between versions to determine if timing and context changes exposed an issue. I will update you as soon as I have more information.

RE: ant scan can't found any device

nanty — Thu, 25 Jun 2026 13:03:31 GMT

HI
Did you find the reason why version 292 doesn't have this problem?

RE: ant scan can't found any device

nanty — Wed, 24 Jun 2026 02:09:13 GMT

Hi，
The project ble_ant_app_hrm_v324.zip and ble_ant_app_hrm_v292.zip that I have provide before, the code is the same, but it has issuse running on V324, while it runs normally on V292. It seems to be unrelated to the printfs? Can you check the differences between the ncs v324 and v292?

RE: ant scan can't found any device

sread — Tue, 23 Jun 2026 14:44:03 GMT

Thanks for checking in, we're working to reproduce this issue now. Is the ANT traffic still the same as the sample project? How frequent are the 0x4015 errors? If you have a log with the latest code we can take a look.

RE: ant scan can't found any device

nanty — Tue, 23 Jun 2026 02:19:05 GMT

Hi,
This issue is affecting our project schedule. Please assist in resolving it and provide the expected repair time. Thank you.

RE: ant scan can't found any device

nanty — Mon, 22 Jun 2026 08:54:03 GMT

Hi,

About this issue, have any update? I have no printfs in "antplus_evt_handler", but I get some feedback that still report 0x4015.

RE: ant scan can't found any device

nanty — Wed, 10 Jun 2026 02:39:32 GMT

Hi,
I have moved my bussiness code in "antplus_evt_handler" to another thread, including the printfs, and the issue not happen for now. But we still hope to know the root cause, and fix it.
Thank you.

RE: ant scan can't found any device

sread — Wed, 10 Jun 2026 01:51:03 GMT

Hello, we're looking into your issue now. I was able to reproduce it with your sample.

What was the reasoning behind introducing prints into the event handler? Have you seen this issue without the prints/sleep in place? I was not able to see it in that case, the scan loop runs to completion. It also seems that the issue doesn't occur using CONFIG_LOG_MODE_DEFERRED=y instead of CONFIG_LOG_MODE_IMMEDIATE. Since the ANT work queue that handles events is cooperative, blocking in the handler starves event dispatch and is discouraged by Zephyr's work queue constraints.

I hope one of those options can unblock your development while we look for a root cause.

RE: ant scan can't found any device

nanty — Mon, 08 Jun 2026 06:53:26 GMT

Hi Kenneth

Briefly, the main test in this project is to repeatedly ANT scan open and close

I have reworked this project to make it more rigorous. To ensure that each close operation is successful, after executing ant_channel_close(ANT_BS_CHANNEL_NUMBER); I use a semaphore and continuously monitor for the callback below. The semaphore is released only after receiving the signal that the channel has been closed.

From the test results, everything runs normally at the beginning, but after about 2-3 minutes, the following exception occurs.

It can be seen that the ANT channel can no longer be closed normally, and this log continues indefinitely. It looks like the ANT thread can no longer recover and is permanently stuck in the logic that reports the channel close failure.

This example can be easily reproduced by using the following standard ANT device for testing. The test device is shown below:

Also, this issue seems to occur only on SDK-ANT 2.1.0; older versions do not have this issue.

Below it is reproduce project：

devzone.nordicsemi.com/.../Test_5F00_ant_5F00_issue.7z

RE: ant scan can't found any device

Kenneth — Thu, 04 Jun 2026 13:52:35 GMT

Hello,

Sorry, not had time to try this yet.

Kenneth

RE: ant scan can't found any device

nanty — Thu, 04 Jun 2026 03:09:46 GMT

Hi Kenneth,
Any update? Does the issue can be reproduced in your side?

RE: ant scan can't found any device

nanty — Wed, 03 Jun 2026 01:43:53 GMT

Hi Kenneth,

I have try to close many times, "ant_channel_close" return 0, and still no EVENT_CHANNEL_CLOSED. The file ”ble_ant_app_hrm_v324_0602.zip“ I have download and unzip is ok. Anyway, I have upload again. Please check.

Thanks.
devzone.nordicsemi.com/.../ble_5F00_ant_5F00_app_5F00_hrm_5F00_v324_5F00_0603.zip

RE: ant scan can't found any device

Kenneth — Tue, 02 Jun 2026 16:11:36 GMT

Hello,

Seems like the zip file is invalid, maybe it wasn't fully uploaded.

Have you tried to call close channel more than one time? Does it return any error?

Kenneth

RE: ant scan can't found any device

nanty — Tue, 02 Jun 2026 12:34:16 GMT

Hi Kenneth,

Any update?

RE: ant scan can't found any device

nanty — Tue, 02 Jun 2026 02:07:47 GMT

Hi Kenneth,

I have confirmed that when I do ant_channel_close, I can't get EVENT_CHANNEL_CLOSED even if timeout 50s. I have added the test project and test log.

devzone.nordicsemi.com/.../54L15_5F00_0602_5F00_0955_5F00_log.txt
devzone.nordicsemi.com/.../ble_5F00_ant_5F00_app_5F00_hrm_5F00_v324_5F00_0602.zip

RE: ant scan can't found any device

Kenneth — Mon, 01 Jun 2026 14:27:49 GMT

Can you wait for a long period of time for test? E.g. 40seconds? I think default search time is around 30 seconds, I just want to understand if it closes at the end.

Kenneth

RE: ant scan can't found any device

nanty — Mon, 01 Jun 2026 12:33:09 GMT

Hi，

This issue occur then I do ant_channel_close and can't get EVENT_CHANNEL_CLOSED response. And ant_channel_status_get() always is 2.

RE: ant scan can't found any device

Kenneth — Mon, 01 Jun 2026 11:55:08 GMT

Hello,

If I remember correctly ant_channel_open() return 0x4015 means channel is in wrong state.

Are you sure the channel is in closed state? E.g. wait for EVENT_CHANNEL_CLOSED before you open it again. When the issue occurs, what does sd_ant_channel_status_get() return?

Kenneth