How to get Peripheral service 128 bit UUID before connection???

[Rekha]

Hi i am using nrf52832 development board as central which scans for peripheral devices.

how to get peripheral device service UUID(128 bit) completely before connection?

is it possible to get uuid either using Advertisement packet or scan response packet ?

Thanks,

Rekha

[Andy]

If you're developing the peripheral you can put a 128-bit UUID in the advertisement/scan response packet, otherwise I don't think it's possible if the UUID is not already there.

[Rekha]

No I am developing on Central side. So only option is to check advertisement data or scan response data for UUID, if not i have to connect and use db_discovery module , Is my understanding correct?

If yes then which variable i need to check in Advertisement packet and scan response packet for UUID?

[Vidar Berg]

The nRF connect app on Android can help you find out what's included in the peripheral's advertisement packet. I suppose you are looking for a UUID, device name, etc that's unique for this device type.  Once you have found out what you want to filter on you can use the BLE scanner module. 

[Rekha]

I think my requirement is not clear. I have central device which scan for peripherals .

in the ble_evt_handler BLE_GAP_EVT_ADV_REPORT: this case gives advertising report, BLE_GAP_EVT_SCAN_REQ_REPORT this case gives scan responses from peripherals.

how do i extract uuid from that scan response or advertising packet is my question. which structure variable should be accessed to get uuid of peripheral services.

Thanks

Rekha

[Rekha]

please upload the code if you have solution for my requirement.

Thanks

[Vidar Berg]

You can use the BLE scanner module to extract UUIDs from the advertisement report event. ble_app_uart_c does this. 

[Rekha]

you mean SCAN FILTERS or manually it is extracting UUID without any encryption decryption mechanism.