CC2640R2F: How to know if CC2640R2F has received the connection request initiated by the host?

Hi team,

Here's the request from the customer:

The project is modified from example Simple peripheral. In practical applications, it is found that other Bluetooth hosts often cannot connect to the slaves. 

As the title says,  how to know if CC2640R2F has received the connection request initiated by the host and where can it be seen?

Could you help check this case? Thanks.

Best Regards,                                                       

Nick