(NRF52810) Subscribe to characteristics fail and issues disconnect to board.

[laird_user]

Hello

We are using custom board which has two chip configuration for BLE stack.
Main MCU runs the Zephyr Host only BT stack in peripheral mode.This is supposed to be GATT server.
Laired connectivity BL651 chip which has nRF52810 MCU, which runs zephyr with HCI ( hci_uart) controller stack.
zephyr version is 1.13.99.

On central side we use Bluegiga BLE module with Python scripts on Windows host.
Python Script is able to connect to the board BLE.
After connection it tries to subscribe one of the characteristics.

As the subscription starts, python script tries to fetch the characteristics for connection 0 by sending attclient_find_information.
packet and then immediately after that disconnect (reason :disconnect EVT from the board.)

Python script also gets error message as "pygatt.backends.bgapi.bgapi:Received a EventPacketType.connection_disconnected"

Any help would be appreciated.

Thanks!

[laird_user]

Another update -
Checked with other centrals also and tried to sniff the packet. What we understood is that moment after connect happens, in a while disconnect event with error 0x0208 is sent.

Also observed one thing, addr_type set in our board is Random. ( this thing we noticed while we were comparing with other logs).