Central Scan Advertising packages buffer size

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Vadym
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Central Scan Advertising packages buffer size

Hi.

I use the BLE on DA14580 part with SDK v_3.0.6.0.
配置的部分是“中央”和lis)ten ( passive scans) for advertising packages.
I receive few reports in series in "gapm_adv_report_ind_handler" in end of the scan cycle.

When I should to receive the reports (in end of scan or when it arrives)?
What is the size of buffer for advertising reports (how many reports)?
And what happens when the buffer overflows?

Thanks a lot!

Device:
MT_dialog
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Joined:2015-06-08 11:34
Hi Vadym,

Hi Vadym,

You should get the advertising messages while scanning is performed not at the end of scanning. You mean how many advertising reports a central can buffer ? That depends on how much advertising reports you want your buffer to handle, when an advertising indication comes the handler is immidiatelly triggered. There is no buffering in the reception of the advertising messages, when the host gets an advertising report it immediately notifies the application for the incoming message. There is a buffer for filtering devices to send scan response data or not and the size is 10 bd_addresses, but this isn't going to prevent you from getting the devices that are advertising.

Thanks MT_dialog

Vadym
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Joined:2015-08-13 08:28
Hi dear support.

Hi dear support.

I have a setup: one BLE device sends advertises packets and second receives the packets.
I try to receive packets in function "app_adv_report_ind_func" that called from "gapm_adv_report_ind_handler". For debugging I toggle the pin every time, when I enter to the function by calling GPIO_SetActive( GPIO_PORT_0, GPIO_PIN_1 ) or GPIO_SetInactive( GPIO_PORT_0, GPIO_PIN_1 ).

I see that I get reports 3 or 4 in series. Time between reports is ~70 microseconds. Time between series corresponds to the frequency of advertises packets. The moment of the reports series doesn't depend on scan cycle, interval or window.
Is the situation right or should I receive the reports not in series?

MT_dialog
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Last seen:2 months 3 weeks ago
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Joined:2015-06-08 11:34
Hi Vadym,

Hi Vadym,

The advertising reports are reported to the host every time he gets an advertising message. You suppose to get the advertising reports in series, one after the other, it isn't possible to get 2 advertising reports at the same time (that would mean that two devices in the same range are using the same medium and the advertising reports will collide).

Thanks MT_dialog