nRF52832 connection problem

[ELIX]

Good day. Some smartphones cannot connect to NRF52832 (SDK17):
- iPhone XR
- iPhone 11
Detection goes well, but smartphones cannot fully connect and freeze at the connection stage. I asked a similar question on the stackerflow and it was suggested to me that the problem might be on the side of NRF52 and that the connection does not work with smartphones with a bluetooth version higher than 5 (with iPhone 7 plus and 6 it works fine).
The board was programmed based on BLE UART firmware. Since the board with vanilla firmware is working fine, it seems that an important code was damaged when modifying the firmware.
Here are the lessons for writing the firmware:
- https://devzone.nordicsemi.com/nordic/short-range-guides/b/bluetooth-low-energy/posts/ble-services-a-beginners-tutorial
- https://devzone.nordicsemi.com/nordic/short-range-guides/b/bluetooth-low-energy/posts/ble-characteristics-a-beginners-tutorial

[Vidar Berg]

Hello,

Please check if you are calling gatt_init() like in the original ble_app_uart() example. This enables the GATT Module that will handle any MTU or data length request sent by the iphone.

The ble_evt_handler() callback should also handle the same events as the original example.

Best regards,

Vidar