Enable notification on TX characteristics on nRF-UART after pairing without bonding on iOS

[Austin Fennacy]

I've seen other users on the DevZone have had a similar problem (link1 link2 link3), but none of their solutions have been able to resolve my problem.

I'm using the BLE App Uart from nRF5_SDK_11.0.0_89a8197\examples\ble_peripheral\ble_app_uart alongside SoftDevice v2.0.0 with the nRF52 DK and an iPhone 5s. In the InfoCenter, it says that "If the peer has enabled notifications for the TX Characteristic, the application can send data to the peer as notifications." My question is, how can I enable notification on TX characteristics on nRF-UART after pairing without bonding? More specifically, is there a modification I can make to the example code that will enable notifications on the TX characteristic?

Not sure if they're any help, but I'll attach some screenshots below.. First 2 are from nRF connect, and I can't tell if the 2nd one indicates that Notify is enabled or just a property? In the 3rd screenshot from nRF Toolbox -> UART's Log, it pretty clearly appears that notifications are enabled for RX Characteristic and I think the notification-enabling is omitted for the TX Characteristic.

edit: after playing around with the nRF Toolbox -> Uart -> Log, I realize the code will only transmit data after 20 characters have filled the TX buffer... So perhaps notifications are enabled for the TX Characteristic but I'm misunderstanding either the UART or the BLE protocol for sending buffered data? Looking into the example code now...

[Mttrinh]

Hi,

When you use UART in nRF Toolbox, notifications are already enabled for the TX characteristic. As for nRF Connect in your second picture, it indicates that Notify is a property. To enable notifications in nRF Connect you have to push the button with the three arrows pointing down. To test if it is working you can send data over a terminal(Termite for instance) from your PC.