Thanks. The attached example does not include AT command handling.
Starting from the ble_at example from the SDK, is there a complete example that also includes OTA UART?

I need to implement the OTA firmware update via UART and with AT commands.
The FR800X_sdk1.2_43ed3f4 SDK contains an example for AT commands, and evt.event_id = AT_RECV_UPGRADE_DATA is also provided.

The procedure begins with AT+MODE:U
at_ota_init(); --> missing api
chk_ret = check_whole_pkt_in_upgrade_mode(); --> missing api
but the code is not complete.

firmware upgrade process is expected while receiving from uart:
app_at_recv_c
if(gAT_ctrl_env.upgrade_start == true)
gAT_env.upgrade_data_processing == 0

Where can I find the complete code and manual?