Can not enable BLE Characteristic indication and notification at same time

RE: Can not enable BLE Characteristic indication and notification at same time

Jayant Tang — Tue, 22 Apr 2025 08:45:39 GMT

Thank you very much. By the way, is this a bug on iOS nRF Connect APP? Because when INDICATION and NOTIFICATION are both permitted, the iOS nRF Connect can only enable Notification.
We tried Light Blue on iOS, it behaves same. But at least the iOS nRF Connect APP should not light the 2 buttons at the same time:

RE: Can not enable BLE Characteristic indication and notification at same time

Emil Lenngren — Mon, 21 Apr 2025 10:00:53 GMT

From the Bluetooth 6.0 spec:

"If both the Notification and Indication bits are set, then the server shall use the notification procedure (see Section 4.10) when an acknowledgment is not required by a higher-layer specification or shall use the indication procedure (see Section 4.11) when
an acknowledgment is required. The server should not use both procedures to send the same characteristic value.
The server may reject a request to set both the Notification and Indication bits for the same characteristic"

RE: Can not enable BLE Characteristic indication and notification at same time

Emil Lenngren — Mon, 21 Apr 2025 09:37:12 GMT

I would bet this is a limitation of CoreBluetooth, where the CCCD write is done "behind the scenes" and perhaps prioritises notifications over indications. You should try this on Android instead, where you have more control.

RE: Can not enable BLE Characteristic indication and notification at same time

Jayant Tang — Mon, 21 Apr 2025 09:37:00 GMT

Andriod Phone seems different. On Andriod nRF Connect APP. It can only enable Indication. Both can't work same time, too

RE: Can not enable BLE Characteristic indication and notification at same time

Jayant Tang — Mon, 21 Apr 2025 09:29:23 GMT

NCS Version: v2.9.0

nRF52840DK