NRF_ERROR_DATA_SIZE when trying to configure/encode adv data in Codec PHY

[Victor Ruiz 26]

Hi,

I was trying to configure adv data such us UUID, major, minor and other data using codec PHY in BLE. I am able to send it correctly using 1M PHY, buy I am having many troubles using Codec.

My project is this one:  0167.ble_app_beacon_.zip and using 

SEGGER Embedded Studio for ARM
Release 7.32 Build 2023081802.53976
Windows x64.

With nRF5 SDK v17.1.0

First of all i have defined two compilation settings (needed for compiling, as i used defined variables on them in advertising_init):

I defined the variables in the first two profiles.

As it is shown in the Preprocessor options:

This project is an advertiser that sends BLE advertisements accord the compilation profile defined. And Tx power and PHY mode can be changed using switches 3 and 2 respectively. 

I have the following NRF_ERROR_DATA_SIZE error using the 1adv_seg compilation environment, please use only this one (in which the tx power change works properly):

The error is in this line:

This worked for me before because I had commented those lines, but when I scanned the adv in Codec mode I realised than it did not contain any advertisement data to obtain and analyze, so I uncommented the lines and the error arose.
I also tried to create a new ble_gap_adv_data_t m_adv_data, defining the len of the p_data defined by other buffer for extended advertisers, as is shown in the image:

Therefore, my issue is inside the ble_advdata_encode for extended advertisements using Codec, and I do not know where is the problem, please if you would help me.

Thanks for the support!

[Vidar Berg]

Hello,

You seem to be using the incorrect BLE_GAP_ADV_TYPE when starting advertising with the coded PHY. This PHY is only supported with extended advertising. Please implement the changes below and let me know if it works or not.

@@ -512,12 +511,12 @@ static void advertising_init(void)
         if(m_adv_scan_type_selected == SELECTION_CONNECTABLE)
         {
    //         NRF_LOG_INFO("Advertising type set to CONNECTABLE_SCANNABLE_UNDIRECTED ");
-            adv_params.properties.type = BLE_GAP_ADV_TYPE_CONNECTABLE_SCANNABLE_UNDIRECTED;
+            adv_params.properties.type = BLE_GAP_ADV_TYPE_EXTENDED_CONNECTABLE_NONSCANNABLE_UNDIRECTED;
         }
         else if(m_adv_scan_type_selected == SELECTION_NON_CONNECTABLE)
         {
    //         NRF_LOG_INFO("Advertising type set to NONCONNECTABLE_SCANNABLE_UNDIRECTED ");
-            adv_params.properties.type = BLE_GAP_ADV_TYPE_NONCONNECTABLE_NONSCANNABLE_UNDIRECTED;
+            adv_params.properties.type = BLE_GAP_ADV_TYPE_EXTENDED_NONCONNECTABLE_NONSCANNABLE_UNDIRECTED;
         }
         
         ret = ble_advdata_encode(&adv_data, m_adv_data.adv_data.p_data, &m_adv_data.adv_data.len);
@@ -549,9 +548,10 @@ static void advertising_init(void)
         {
     //        NRF_LOG_INFO("Advertising type set to EXTENDED_NONCONNECTABLE_SCANNABLE_UNDIRECTED ");
             adv_params.properties.type = BLE_GAP_ADV_TYPE_EXTENDED_NONCONNECTABLE_NONSCANNABLE_UNDIRECTED;
+            // Re-init '.len'paramater to default value in case it was updated by previous call to ble_advdata_encode()
+            m_adv_data_ext.adv_data.len = BLE_GAP_ADV_SET_DATA_SIZE_EXTENDED_MAX_SUPPORTED;
 
-
-            ret = ble_advdata_encode(&adv_data, m_adv_data_ext.scan_rsp_data.p_data, &m_adv_data_ext.scan_rsp_data.len);
+            ret = ble_advdata_encode(&adv_data, m_adv_data_ext.adv_data.p_data, &m_adv_data_ext.adv_data.len);
             APP_ERROR_CHECK(ret);
 
             ret = sd_ble_gap_adv_set_configure(&m_adv_handle, &m_adv_data_ext, &adv_params);

Best regards,

Vidar

[Victor Ruiz 26]

Yes, the first block of code you posted is inside condition: if(m_adv_scan_phy_selected == SELECTION_1M_PHY). The block:

So I think that my initialization is correct in mode 1M.

The second block is referred to m_adv_scan_phy_selected as Codec PHY. And the m_adv_data_ext is another structure that i used for initialising the m_adv_handle for this mode. And I do not modify this structure anywhere 

Here is the question, should I use the same ble_gap_adv_data_t structure for both phy modes? If it is, I should define the ble_gap_adv_data_t->adv_data->p_data  m_enc_advdata array as BLE_GAP_ADV_SET_DATA_SIZE_EXTENDED_MAX_SUPPORTED, right? 

But by this way, I would send many unnecessary data when using 1M PHY mode...

So, which is the way to create these structures and changing each other as change the PHY mode?

Thanks.

[Vidar Berg]

Sorry, I was reviewing the code for the wrong if statement. However, I believe it should work if you ignore the first part and apply only the last part of my patch starting at line 549.

[Victor Ruiz 26]

Oh Sorry, It works now. The error occurred when the ble_adv_data_enconde function was called with the wrong m_adv_data_ext parameters (i was passing .scan_rsp_data.p_data, scan_rsp_data.len instead of .adv_data.p_data and adv_data.len).

Thank you so much for the support!

[Victor Ruiz 26]

Hi Vidar. 
Which is the utility of scan_rsp_data inside ble_gap_adv_data_t m_adv_data structure?

Are these data values that the BLE receives? Or are prefixed (or modificable at running time?) data that the advertiser returns to an adv_scan_req?

My question comes because i want to implement a system where the central receives advertisements from the peripheral and when i press a button in the central, for example, it sends an advertisement to which the peripheral would respond, all this without connecting the devices. I mean, all communication is using advertisements, I one case undirected (from peripheral to central) and in the other case (when button pressed, from central to peripheral), directed to that peripheral

I do not know ir this approach is correct, or i would implement connectable advertisements and ble_events.

Thanks in advance

[Vidar Berg]

Hi,

The advertisement type you have selected is 'non-scannable', which means you cannot send any scan response. Therefore, there is no need to provide a buffer for scan response data either.

Victor Ruiz 26 said:

My question comes because i want to implement a system where the central receives advertisements from the peripheral and when i press a button in the central, for example, it sends an advertisement to which the peripheral would respond, all this without connecting the devices. I mean, all communication is using advertisements, I one case undirected (from peripheral to central) and in the other case (when button pressed, from central to peripheral), directed to that peripheral

Is there a reason you don't want to make it connection-based? The setup you describe means that the devices will need to operate in both a GAP Observer role and a GAP Broadcaster role. It is not going to be very efficient in terms of power usage.