Direct advertising to the host by its Bluetooth Device Address (Windows)

[CY]

Hi,

Just would like to know is it possible to proceed auto pairing by restore the MAC address of host?

The current idea is using direct advertising to speed up the pairing process with the BT address.

Meanwhile, the host would also restore the device BT address and scan to establish connection.

However, it will be without bonded information due to the device and host were not paired before but just have a way to restore each address.

In more detail, the development is used for Human Interface Device. We would like to make it direct advertising to connect to the target PC without bonded info but just BT address only.

Is it possible to achieve? How is the feasibility? If it is possible, any API or sample I could refer?

And if the connection established, would they make bonded info in further?

Thanks,

Wedy

[Amanda Hsieh]

Hi Wedy, 

You would need to use bonding and whitelisting so that the devices will connect to the device which MAC address is in the whitelist. 

You can refer to our example HID Mouse Application (or HID Keyboard Application). In the example, after bonding we will do directed advertising and after that will do whitelisting advertising,  after the whitelist advertising timeout, it will advertise in normal mode. 
To be able to make sure there will be no other device to connect to your device, you can disable the timeout to normal mode. Only advertise in whitelisting mode. 

-Amanda H.

[CY]

Hi Amanda,

I understood your explain and indeed I also use the sample for development.

However, my question is whether the bonded info is must required for direct advertising?

And are you saying that I just need to add the MAC address into my whitelist then it could proceed auto pairing to connect with the PC it never paired before.

Thanks,

Wedy

[Amanda Hsieh]

Hi Wedy,

CY said:

my question is whether the bonded info is must required for direct advertising?

In a normal use case, direct advertising only makes sense when bonded, since then you know which device you should advertise directed to. Also, please note that directed advertising is only suitable for some special occasions, such as HID mouse and keyboards where you want very fast direct advertisement after a connection loss in order to seamlessly reconnect. You may not see so easily how this is done in the HID example since it uses the advertising module. Essentially the advertising module starts with the most aggressive and most restrictive advertising mode and goes down the list, subsequently using each mode until it's timeout as long as it is enabled. You can most easily see this by looking at the implementation of adv_mode_next_avail_get() in components\ble\ble_advertising\ble_advertising.c.

If you don't plan to bond but still want to have whitelist. You have to manage the whitelist manually. Here you can find an example of how to do it manually (this is for whitelist with advertising) 

CY said:

are you saying that I just need to add the MAC address into my whitelist then it could proceed auto pairing to connect with the PC it never paired before.

 No, I don't think so because the central device doesn't have the pair info. 

-Amanda H.