I am connecting a nrf 52480 board(Adafruit fether express) to a custom M4 cortex board with the help of nordic serialisation library. I have ported the serialisation library from nrf sdk for the custom board and connectivity board (nrf 52480) is flashed with the connectivity application from nrf sdk. I am able to start the ble advertisement(nordic hrs example) using this setup. From phone when it tries to connect to it , using the nrf Toolbox application, the BLE connected event is reached to application chip , but application chip is calling this sd_ble_gattc_exchange_mtu_request api while proccessing the connected event. But the application chip doesn't seems to be sending any bytes to the connectivity chip, and connectivity chip is timing out.
Is there any known issue in the sd_ble_gattc_exchange_mtu_request implementation in serialisation library?
Could you please help to debug the issue.
Or suggest some possible reason for the issue
softdevice: s140