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Anonymous
Not applicable

Hi all,

My table is like this:

const BLE_PROFILE_CFG contact_exchg_cfg =

{

  /*.fine_timer_interval            =*/ CONTACT_EXCHG_FINE_TIMER, // 500 ms

  /*.default_adv                    =*/ 4,    // HIGH_UNDIRECTED_DISCOVERABLE

  /*.button_adv_toggle              =*/ 0,    // pairing button make adv toggle (if 1) or always on (if 0)

      /*.high_undirect_adv_interval     =*/ 200, // slots (320 = every 200 ms)

      /*.low_undirect_adv_interval      =*/ 200, // slots

      /*.high_undirect_adv_duration     =*/ 4,   // seconds

      /*.low_undirect_adv_duration      =*/ 4,  // seconds

  /*.high_direct_adv_interval       =*/ 0,    // seconds

  /*.low_direct_adv_interval        =*/ 0,    // seconds

  /*.high_direct_adv_duration       =*/ 0,    // seconds

  /*.low_direct_adv_duration        =*/ 0,    // seconds

...

};

where one can see that High and Low advertising parameters are identical and set to 125 ms interval.

If I call

bleprofile_Discoverable(HIGH_UNDIRECTED_DISCOVERABLE, NULL);

I do get an interval of 125 ms, which is what I expected.


But if I call

bleprofile_Discoverable(LOW_UNDIRECTED_DISCOVERABLE, NULL);

I see an interval of 1 s (and I did NOT expect to see that).

Why is it different?  Now I'm confused about this "high" vs. "low" advertising.  Why did it divide the frequency (multiplied the interval) by 8?

Thanks,

Gil

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1 Solution
Anonymous
Not applicable

I found some information about "low duty cycle advertising" here:

https://www.bluetooth.org/docman/handlers/DownloadDoc.ashx?doc_id=260859&vId=303201

Still not 100% but it seems that "low" and "high" refer to the duty cycle inside the advertisement packet.

View solution in original post

3 Replies
Anonymous
Not applicable

Helpful tip... I'm trying to understand what "low" and "high" really mean.

1. Interval between advertisement events?

2. Duty cycle within advertisement packet?

3. Tx power used in advertisement?

I'm not sure anymore...

Anonymous
Not applicable

I found some information about "low duty cycle advertising" here:

https://www.bluetooth.org/docman/handlers/DownloadDoc.ashx?doc_id=260859&vId=303201

Still not 100% but it seems that "low" and "high" refer to the duty cycle inside the advertisement packet.

ShawnA_01
Employee
Employee
25 solutions authored 10 solutions authored 5 solutions authored

There is some good discussion of it in the Video Link : 1218 look specifically at Time = 2min, 15 seconds, but the whole video series is helpful.

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