ble_advertising problem with broadcasting

[relavak]

There appears to be a conflict between ble_advertising and broadcasting while connected. If connected, the ble_advertising state machine still gets TIMEOUT messages from the broadcast and fails to ignore them and then advances the ble_advertising state machine into generating its own advertising packets while will cause false broadcasting. The ble_advertising state machine should ignore those TIMEOUT messages. I don't see a workaround other than compiling my own version of ble_advertising with a check to ignore timeouts if connected. Perhaps a better/proper fix for the Nordic SoftDevice would be to use a different timeout src: BLE_GAP_TIMEOUT_SRC_BROADCASTING for the evt.gap_evt.params.timeout.src field.

[Vidar Berg]

Hi,

The advertisment module does not cover all use cases, so you may have to modify the module to suit your requirements, or access the softdevice API directly from your app. Which SDK version are you using? I can try to see if it is be possible to work around this without modifying the module. 

[relavak]

I'm using the toolkit  nRF5_SDK_14.1.0_1dda907 s132 armgcc architectures. I copied the code into my own project and then modified it thusly:

--- ble_advertising.c	2018-07-09 17:06:11.690065826 -0700
+++ /home/scanner/ble_advertising.c	2018-08-03 16:13:07.912088784 -0700
@@ -114,9 +114,9 @@
 
     p_advertising->whitelist_temporarily_disabled = false;
 
-    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)
-    {
+    if (p_ble_evt->evt.gap_evt.conn_handle == p_advertising->current_slave_link_conn_handle) {
+	p_advertising->current_slave_link_conn_handle = BLE_CONN_HANDLE_INVALID;
+	if(p_advertising->adv_modes_config.ble_adv_on_disconnect_disabled == false) {
        ret = ble_advertising_start(p_advertising, BLE_ADV_MODE_DIRECTED);
        if ((ret != NRF_SUCCESS) && (p_advertising->error_handler != NULL))
        {
@@ -124,6 +124,7 @@
        }
     }
 }
+}
 
 
 /**@brief Function for handling the Timeout event.
@@ -135,7 +136,8 @@
 {
     ret_code_t ret;
 
-    if (p_ble_evt->evt.gap_evt.params.timeout.src != BLE_GAP_TIMEOUT_SRC_ADVERTISING)
+    if (p_ble_evt->evt.gap_evt.params.timeout.src != BLE_GAP_TIMEOUT_SRC_ADVERTISING 
+	|| p_advertising->current_slave_link_conn_handle != BLE_CONN_HANDLE_INVALID)
     {
         // Nothing to do.
         return;

 

[Vidar Berg]

Thanks for posting the changes you made, it's more clear now. I think this might be the best way to solve the problem for your use case. Another possible alternative could be to start brodcast advertising using the ble_advertising_start() with a mode that is followed by BLE_ADV_MODE_IDLE.