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How much of extended adverts is supported in the latest Softdevice

Hi

We have a lot of customers asking for full extended adverts features as per the latest spec in terms of all types of adverts and also other PHYs

Apparently other BLE SoC manufacturers offer that functionality.

Is there a summary of what is and what is not supported in the latest softdevice?

And for the stuff not supported, is there a plan to do so?

We are losing customers.

Look forward to hearing from you

Kind regards
Mahendra

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  • Hi Mahendra,

    The latest softdevices (s132/s140 v6.1.1/7.0.0) support the following features, as mentioned in the key features of softdevice specifications:

    Extended Advertising support

    • Advertising and scanning up to 255 bytes of advertising data in an advertising event
    • Advertising, scanning, and connecting on all supported PHYs
    • Anonymous advertising

    The only non-supported feature is the periodic advertising, which we are working on adding into future softdevices. For details on roadmaps and release schedule, you need to contact your regional sales manager.

    Best regards,
    Jørgen

  • Thank you for the prompt response.

    You say "Advertising and scanning up to 255 bytes of advertising data in an advertising event" 

    Can you confirm that this is not chained adverts in the sense that you are allowing the AUX_ADV_IND but disallowing the AUX_CHAIN_IND that can as per the spec follow with up to 5 or 6 of them.


    In addition, looking at Table 2.5 on page 2573 of the 5.0 spec, it shows that the AUX_ADV_IND contains the CEAP payload which can contain the Adv Data. Given there are other fields in the CEAP, does your statement above about 255 bytes refer to the size of the CEAP or can we actually add AD data that is 255 bytes long (the spec says this field can be 0-254 octets on page 2580)?

    I ask in the context of the spec which allows up to 1650 of advertising data to be fragmented over multiple ADV_CHAIN_IND that can be pointed to by a AUX_ADV_IND

    BTW: the spec on page 2586 says ...


    The Host may indicate a preference whether the Controller should fragment the Host advertising data, but the Controller may ignore the preference

    Which seems to suggest that your developers have made the decision to not allow fragmentation.


    And it goes on to say ...

    If the amount of advertising or scan response data to be sent in an extended advertising or scanning PDU plus the Extended Header Length, AdvMode, and Extended Header exceed the maximum Advertising Channel PDU payload (255 octets), the Link Layer shall fragment the Host advertising data.

    And that seems to indicate that the AD Data field in the CEAP in the softdevice is going to be something less than the 255 you mention.
    Would you be able to provide a definitive limit on that size?

    Also if that field is provided by the application and it will result in fragmentation (extended over in AUX_CHAIN_IND which you may not be supporting ) then does the softdevice return an appropriate error?

    I further will be most grateful if you can confirm one way or the other if you ever plan to support AUX_CHAIN_IND packets - as that implies fragmentation 

    Look forward to your response.

Reply
  • Thank you for the prompt response.

    You say "Advertising and scanning up to 255 bytes of advertising data in an advertising event" 

    Can you confirm that this is not chained adverts in the sense that you are allowing the AUX_ADV_IND but disallowing the AUX_CHAIN_IND that can as per the spec follow with up to 5 or 6 of them.


    In addition, looking at Table 2.5 on page 2573 of the 5.0 spec, it shows that the AUX_ADV_IND contains the CEAP payload which can contain the Adv Data. Given there are other fields in the CEAP, does your statement above about 255 bytes refer to the size of the CEAP or can we actually add AD data that is 255 bytes long (the spec says this field can be 0-254 octets on page 2580)?

    I ask in the context of the spec which allows up to 1650 of advertising data to be fragmented over multiple ADV_CHAIN_IND that can be pointed to by a AUX_ADV_IND

    BTW: the spec on page 2586 says ...


    The Host may indicate a preference whether the Controller should fragment the Host advertising data, but the Controller may ignore the preference

    Which seems to suggest that your developers have made the decision to not allow fragmentation.


    And it goes on to say ...

    If the amount of advertising or scan response data to be sent in an extended advertising or scanning PDU plus the Extended Header Length, AdvMode, and Extended Header exceed the maximum Advertising Channel PDU payload (255 octets), the Link Layer shall fragment the Host advertising data.

    And that seems to indicate that the AD Data field in the CEAP in the softdevice is going to be something less than the 255 you mention.
    Would you be able to provide a definitive limit on that size?

    Also if that field is provided by the application and it will result in fragmentation (extended over in AUX_CHAIN_IND which you may not be supporting ) then does the softdevice return an appropriate error?

    I further will be most grateful if you can confirm one way or the other if you ever plan to support AUX_CHAIN_IND packets - as that implies fragmentation 

    Look forward to your response.

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