BLE_SCAN_TYPE

kishan patel
Posts: 45
Joined: Wed Aug 30, 2017 4:56 am

BLE_SCAN_TYPE

Postby kishan patel » Wed Dec 27, 2017 8:52 am

Hello,
I have scanning ble and its working properly.
But i have some doubt about scanning parameters.I had checked its declaration and comments but i could not find proper use of it.

Means what is the difference if i set scan_type as ACTIVE or PASSIVE.

Thanks in advance.

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kolban
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Joined: Mon Nov 16, 2015 4:43 pm
Location: Texas, USA

Re: BLE_SCAN_TYPE

Postby kolban » Thu Dec 28, 2017 3:57 am

This is a BLE concept. A passive scan means the BLE client receives the advertisement and that is the end of the story. The client just receives (passively) advertisements. When we have an active scan, then when the client receives an advert, the client turns around sends a "Scan Request" back to the BLE server which responds with a second advertisement packet. This effectively doubles the amount of advertising data available to a client.
Free book on ESP32 available here: https://leanpub.com/kolban-ESP32

kishan patel
Posts: 45
Joined: Wed Aug 30, 2017 4:56 am

Re: BLE_SCAN_TYPE

Postby kishan patel » Mon Jan 01, 2018 11:35 am

Okay and Thanks for reply.

Can you tell me other configuration setting functionality like time_interval,window,etc.

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kolban
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Location: Texas, USA

Re: BLE_SCAN_TYPE

Postby kolban » Mon Jan 01, 2018 11:23 pm

Howdy ... unfortunately I think that's a tall order. What I'd like to suggest is to get some books on BLE. I bought a subscription to Safari on-line books and have read three now and its just starting to make sense. The specifications for BLE and public at the BLE web site but a little "dry" to comprehend. Rather than try and describe all permutations and possibilities, let me encourage you to read what is available on BLE in general and then come back to ESP32 in particular. When you have specific questions about how to achieve a goal that is possible in theoretical BLE on the ESP32, that would be a great time to ask questions.
Free book on ESP32 available here: https://leanpub.com/kolban-ESP32

kishan patel
Posts: 45
Joined: Wed Aug 30, 2017 4:56 am

Re: BLE_SCAN_TYPE

Postby kishan patel » Thu Jan 04, 2018 5:15 am

Hello,

Actually,i want to know about BLE configuration because of i have getting some issue in my project.
Like as some time i could not scan ble_tags.
I have scanning tags for 10 seconds in every 30 seconds.
And i can detect 30 to 40 tags.
And sometimes only 2 to 4.

So,what would be reason behind it.

Because of that issue,it reveals that tags are not available near scanning device.Its wrong.

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