RE: [BLE] why restart advertising after disconnect?

lyrics — Mon, 06 Sep 2021 02:26:20 GMT

Hi, I'm sorry for late reply.

I understand your explanation for question 1. Thank you.

[quote userid="7377" url="~/f/nordic-q-a/79251/ble-why-restart-advertising-after-disconnect/327936#327936"]Where do you look for the event, and in what situation?[/quote]

I asked this question because I didn't understand the above case, but I think I missed some of this, so I'll ask you additional questions later.

Thank you. :)

RE: [BLE] why restart advertising after disconnect?

Einar Thorsrud — Fri, 03 Sep 2021 09:36:14 GMT

Hi Lyrics,

[quote user=""]

1. my question is, what is meaning of

" if (p_ble_evt->evt.gap_evt.conn_handle == p_advertising->current_slave_link_conn_handle &&
p_advertising->adv_modes_config.ble_adv_on_disconnect_disabled == false) "

and why it restart advertising?

[/quote]

The reason the advertising module supports automatically starting to advertise upon a disconnect is that this is a very common scenario. However this is configurable and if you do not want it, you can disable it. Looking at the code snippet you posed, you see the ble_adv_on_disconnect_disabled field is what is relevant here. This can be set in the configuration struct before you call ble_advertising_init(), as is demonstrated in <SDK 17.0.2>\examples\ble_peripheral\experimental\ble_app_cgms\main.c. You can also set it at a later point if you want it normally on, but to disable it at a specific point, as demonstrated in for instance <SDK17.0.2>\examples\ble_peripheral\ble_app_buttonless_dfu\main.c.

[quote user=""]

And, when it restarts advertising because of above code part, BLE_GAP_EVT_DISCONNECTED case in the ble_evt_handler is not triggered.

(but it triggered well if I erase restart advertising code part..)

2. Does this mean that it didn't disconnected properly? Why this problem happening?

[/quote]

I did not get that. You should always get the BLE_GAP_EVT_DISCONNECTED if there as been a disconnect. Can you explain in more detail? Where do you look for the event, and in what situation? Please elaborate.