RE: Unable to connect

Kenneth — Wed, 24 Apr 2019 14:16:30 GMT

Hi,

There are typically 2 reasons why BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED may occur:

1. There is noise in the environment that cause the connection request packet to be lost, this may occur from time to time (e.g. 1-5%) depending on other 2.4GHz traffic, but not all the time no.

2. The peripheral you want to connect to have enabled whitelist to prevent new central devices to connect and bond, in such case you may need to put the peripheral device in a pairing mode by following the manufacturer description.

Can any of the above be the case here?

If not, then an on-air sniffer log with working and failing situation (e.g old and new software) could be useful:

https://www.nordicsemi.com/Software-and-Tools/Development-Tools/nRF-Sniffer

https://www.nordicsemi.com/Software-and-Tools/Development-Tools/nRF-Connect-for-desktop/Download#infotabs

Best regards,
Kenneth