What is the time duration as the Cypress chip writes a new Advertising Channel index?

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Anonymous
Not applicable

According to the BLE 5.0 Specification :

"The Link Layer shall use the primary and secondary advertising channel

indices as specified by the Host, and the used primary and secondary

advertising channel indices shall take effect when the Advertising State is

entered.

So if I understand the spec correctly, with each advertising event, the Advertising Channel Indices are rewritten with each event.

Forgive my question, what is the time duration of this rewriting of the Advertising Channel Indices?  I guess that this occurs in less than 1 mS.  And that this rewriting is occurring concurrently with advdelay, the advertising delay inserted between each advertising event.  Advdelay is typically 10mS plus a random delay, if I remember the spec correctly.  Since it is concurrent with advdelay, I should just ignore the duration of the rewriting of the Advertising Channel Indices?

Can anyone confirm that the Cypress chips function in general this way?  Thank you!  

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Anonymous
Not applicable

Based on the wording you quoted, I would take it to mean that the advertising channel index is chosen when the unit starts advertising, not at each packet advertise event. Thus, the indices would get rewritten each time you stop, then start advertising again.

As far as the timing, if you specify the advertising interval to be 10 mS with some random delay, then the time from a packet being electrically transmitted until the next packet is electrically transmitted should be the 10 ms with some random delay; The 1 ms expected delay from index assigning for the channels shouldn't be included in that timing (also, if the indices are only assigned on starting advertising from an inactive radio state like I mentioned above, then it would only affect the startup time for the first advertisement packet if at all).

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Anonymous
Not applicable

Based on the wording you quoted, I would take it to mean that the advertising channel index is chosen when the unit starts advertising, not at each packet advertise event. Thus, the indices would get rewritten each time you stop, then start advertising again.

As far as the timing, if you specify the advertising interval to be 10 mS with some random delay, then the time from a packet being electrically transmitted until the next packet is electrically transmitted should be the 10 ms with some random delay; The 1 ms expected delay from index assigning for the channels shouldn't be included in that timing (also, if the indices are only assigned on starting advertising from an inactive radio state like I mentioned above, then it would only affect the startup time for the first advertisement packet if at all).

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