After BLE_GAP_EVT_DISCONNECTED event advertisement module stops

[Ranajyoti Chakraborti]

Hi

I have written this code based on a sample from SDK12. The board is a pca10040 and nRF52832 chip. It seems like after disconnection from the master device the Softdevice is not starting the advertisement again, which according to the documentation should be the case. I have to reset the board using nrfjprog in order to start advertising again. I do not handle this even in the code and I found out that BLE_GAP_EVT_DISCONNECTED is fired by SoftDevice after disconnection. Please advise. This a show stopper.

[Edvin]

Hello,

You  need to start the advertisement somewhere in the source code after a disconnect event. 

 

In most of the examples in SDK 12 (I have checked SDK12.3.0, since you didn't specify one specific, but I assume that it is the same in the other SDK12.x.x) the ble_advertising_start(...) call is done in the on_disconnect() function, which is called in the BLE_GAP_EVT_DISCONNECTED event in in the ble_advertising_on_ble_evt(...) function inside the ble_advertising.c file.

 

Have you changed anything in this file?

 

Best regards,

Edvin

[Ranajyoti Chakraborti]

No I have not touched any library file. I took the initial code from the Heart Rate in the peripheral section of the examples and wrote custom service on top of that. I had tried adding ble_advertising_start on the handler of BLE_GAP_EVT_DISCONNECTED. There is no failure on the ble_advertising_start but the advertising does not actually start. It would only start if I reset the app with a APP_ERROR_CHECK with some error code. I also had advertising started on PM_EVT_PEERS_DELETE_SUCCEEDED, but this event is never fired. My guess is that this is for Central devices and not peripheral ones. I also checked the ble_app_hrs code again and there is no advertisement start in the BLE_GAP_EVT_DISCONNECTED  code.

[Edvin]

What SDK version do you use? I don't know if it is any difference in the advertising_start implementation between the SDK12.x.x versions, but if you could tell me, we might avoid some misunderstandings. Can you check the ble_advertising.c file, and search for BLE_GAP_EVT_DISCONNECTED in that file? It should call a function named on_disconnect(), where it should call ble_advertising_start().

 

BR,

Edvin

[Ranajyoti Chakraborti]

SDK Version is 12.3.0 here is the code from ble_advertising.c

void ble_advertising_on_ble_evt(ble_evt_t const * p_ble_evt)
{
switch (p_ble_evt->header.evt_id)
{
case BLE_GAP_EVT_CONNECTED:
on_connected(p_ble_evt);
break;

// Upon disconnection, whitelist will be activated and direct advertising is started.
case BLE_GAP_EVT_DISCONNECTED:
on_disconnected(p_ble_evt);
break;

// Upon time-out, the next advertising mode is started.
case BLE_GAP_EVT_TIMEOUT:
on_timeout(p_ble_evt);
break;

default:
break;
}
}

and here is the dispatcher code

static void ble_evt_dispatch(ble_evt_t * p_ble_evt)
{
ble_conn_state_on_ble_evt(p_ble_evt);
pm_on_ble_evt(p_ble_evt);
ble_conn_params_on_ble_evt(p_ble_evt);
m_ble_evt_handler(p_ble_evt);
ble_advertising_on_ble_evt(p_ble_evt);
nrf_ble_gatt_on_ble_evt(&m_gatt, p_ble_evt);
}

[Ranajyoti Chakraborti]

I debugged through the ble_advertising code and the ble_advertising_starts returns 0

[Edvin]

I assume that you use the softdevice that comes with the SDK?

 

Is it possible to send the project? If ble_advertising_start() returns 0 and it doesn't start advertising, then it might be a softdevice bug. I would very much like to try to replicate this if possible.

 

Best regards,

Edvin

[Ranajyoti Chakraborti]

Yes I use the softdevice, it is possible to send the project, how do I send it?

[Ranajyoti Chakraborti]

Hi Edvin 

If you can kindly respond.