NRF_ERROR_BUSY returned, re-starting BLE beacon advertising

RE: NRF_ERROR_BUSY returned, re-starting BLE beacon advertising

Petter Myhre — Mon, 02 Nov 2015 13:58:47 GMT

In ble_stack_init() you need to add:

// Register with the SoftDevice handler module for BLE events.
err_code = softdevice_ble_evt_handler_set(ble_evt_dispatch);
APP_ERROR_CHECK(err_code);

And you need to define the event handler:

static void ble_evt_dispatch(ble_evt_t * p_ble_evt)
{
    if((p_ble_evt->header.evt_id == BLE_GAP_EVT_TIMEOUT) && (p_ble_evt->evt.gap_evt.params.timeout.src == BLE_GAP_TIMEOUT_SRC_ADVERTISING))
    {
         //Start advertising or not
    }
}

RE: NRF_ERROR_BUSY returned, re-starting BLE beacon advertising

Brian — Sat, 31 Oct 2015 01:28:55 GMT

Thanks Petter... really appreciated.

One last question. I'm using the template/example provided in SDK 9-2, ble_app_beacon, and its not clear to me where to initialize advertising with a callback to an event handler to catch BLE_GAP_EVT_TIMEOUT as you point out. Is it possible?

Thanks, Brian

You can also skip the timer. Set the timeout to 1 second, and the interval to for example 1100 ms. Then when you get BLE_GAP_EVT_TIMEOUT you start advertising again, or not.

RE: NRF_ERROR_BUSY returned, re-starting BLE beacon advertising

Petter Myhre — Tue, 27 Oct 2015 15:18:26 GMT

If you are not doing anything else, for example scanning or something else (I don't know what SoftDevice you are using) the advertisement will be sent pretty quickly, but exactly how fast I don't know. 100 ms should be fine. You can find out by using Radio Notifications or a sniffer.

You can also skip the timer. Set the timeout to 1 second, and the interval to for example 1100 ms. Then when you get BLE_GAP_EVT_TIMEOUT you start advertising again, or not.

I also want to point out that when I say one advertisement, I mean three advertising packet on each of the three advertising channels.

RE: NRF_ERROR_BUSY returned, re-starting BLE beacon advertising

Brian — Tue, 27 Oct 2015 14:31:21 GMT

Also, if I really only want to send on advertisement per second, how quickly should I stop advertising after starting it? ~999ms? Assuming an interval of 1000ms. In other words, after starting advertising, how quickly is that first advertisement sent? Thanks!

RE: NRF_ERROR_BUSY returned, re-starting BLE beacon advertising

Brian — Tue, 27 Oct 2015 14:28:56 GMT

Yup. Got that. What I'm finding in SDK9-2 is that if the timeout is 1 second. And I wait more than 1 second after starting advertising, then trying to restart advertising after the timeout period I get the NRF_BUSY error.

With timeout of 1 second, and a delay of only 500ms, let's say, then stoping and starting works ok. Seems strange... but no big deal. Now I'm just setting the timeout to 0, and manually starting and stopping and it's working ok.

RE: NRF_ERROR_BUSY returned, re-starting BLE beacon advertising

Petter Myhre — Tue, 27 Oct 2015 08:21:43 GMT

What error code do you get with sd_ble_gap_adv_stop()?

RE: NRF_ERROR_BUSY returned, re-starting BLE beacon advertising

Petter Myhre — Tue, 27 Oct 2015 08:21:18 GMT

#define APP_CFG_NON_CONN_ADV_TIMEOUT  1
#define NON_CONNECTABLE_ADV_INTERVAL    MSEC_TO_UNITS(1000, UNIT_0_625_MS)

This will send one advertisement per second for 1 second.

#define APP_CFG_NON_CONN_ADV_TIMEOUT  0
#define NON_CONNECTABLE_ADV_INTERVAL    MSEC_TO_UNITS(1000, UNIT_0_625_MS)

This will send one advertisement per second forever, or until you call sd_ble_gap_adv_stop().

If you always want to stop the advertisements manually you can set the timeout to 0.

RE: NRF_ERROR_BUSY returned, re-starting BLE beacon advertising

Brian — Tue, 27 Oct 2015 04:01:23 GMT

Hi Petter,

Thanks for the response. I figured something out:

The settings causing this behavior are:

#define APP_CFG_NON_CONN_ADV_TIMEOUT  1
#define NON_CONNECTABLE_ADV_INTERVAL    MSEC_TO_UNITS(1000, UNIT_0_625_MS)

If I change to:

#define APP_CFG_NON_CONN_ADV_TIMEOUT  0
#define NON_CONNECTABLE_ADV_INTERVAL    MSEC_TO_UNITS(1000, UNIT_0_625_MS)

Then no problem. Why is this? I'm trying to just send one advertisement per second, but be able to start and stop. Should these settings also send just one advertisement per sec?

Thanks, Brian

RE: NRF_ERROR_BUSY returned, re-starting BLE beacon advertising

Petter Myhre — Mon, 26 Oct 2015 09:40:45 GMT

I'm not sure what is causing this. Would it be possible for you to upload your complete project? Or a project that produces the error? What SoftDevice and SDK version are you using?