Change BLE attribute dynamically on NCS

RE: Change BLE attribute dynamically on NCS

Einar Thorsrud — Wed, 12 Feb 2025 13:37:44 GMT

Hi,

I do not believe there is any way to just modify the service dynamically. However, it should be possible to unregister and register a modified service that happens to be the same except for change to the permissions of one characteristic. (using bt_gatt_service_register() and bt_gatt_service_unregister()).

RE: Change BLE attribute dynamically on NCS

Beldramma — Tue, 11 Feb 2025 11:12:40 GMT

Hi khelmutlord ,

Thanks for the link, it seems interesting, but if I understand well it is used to add dynamically a service.

What I want to do is to modify an existing service, and if possible if a client is already connected.

More specifically, I want to modify the permissions of a characteristic.

I can see that you enable the "Service changed" characteristic from the GATT service, do you think it can manage my case ?

Do you have an example of implementation for my case ?

Thanks in advance !

RE: Change BLE attribute dynamically on NCS

khelmutlord — Mon, 10 Feb 2025 19:13:14 GMT

I have a pending PR that should help w/ dynamic service creation. https://github.com/zephyrproject-rtos/zephyr/pull/84401

There is not currently a sample that demonstrates how to use these APIs.

Let me know if this helps!