Service and Characteristic discovery of GATT server on central

RE: Service and Characteristic discovery of GATT server on central

Vidar Berg — Fri, 11 Feb 2022 13:38:46 GMT

Thanks for the update and feedback. Yes, I agree that it may not be immediately obvious that you have to reference the UUID using the tag returned by sd_ble_uuid_vs_add().

RE: Service and Characteristic discovery of GATT server on central

demJanus — Fri, 11 Feb 2022 13:34:02 GMT

Yes I did register it. Menwhile I found out that I need to use the handle that gets provided when registering the service and not BLE_UUID_TYPE_VENDOR_BEGIN.

This could be pointed out a bit more clearly. Not clear to me from the tutorials.

The following threads gave an indication to the reason for me:

https://devzone.nordicsemi.com/f/nordic-q-a/206/128-bit-uuid-s

https://devzone.nordicsemi.com/f/nordic-q-a/52390/understanding-advertisement-of-multiple-128-bit-custom-uuid/212429

https://devzone.nordicsemi.com/f/nordic-q-a/21152/db-discovery-failing-with-ble_db_discovery_srv_not_found

Thanks for your support anyway.

RE: Service and Characteristic discovery of GATT server on central

Vidar Berg — Wed, 09 Feb 2022 13:04:52 GMT

Hello,

[quote user=""]If I use the 0x180A for the DIS service instead of the characteristic 0x2A29 the handler is called only twice[/quote]

Yes, it's the service UUID you need to register with the DB discovery module. The characteristics are then found by you in the discovery_handler() after the service has been discovered. I posted an example of this here: https://devzone.nordicsemi.com/f/nordic-q-a/49837/reading-the-central-device-name-smart-phone-in-nrf52dk-peripheral-and-printing-on-the-terminal/199126#199126

[quote user=""]custom service (0000AABBCCDD11223344556677889900) with one characteristic (0000AABCCCDD11223344556677889900) on the nrf connect application.[/quote]

Did you register this UUID with sd_ble_uuid_vs_add() on the peripheral?

Thanks,

Vidar