Lots of BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED (0x3E) when using PCA10100

RE: Lots of BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED (0x3E) when using PCA10100

Vidar Berg — Fri, 06 Jan 2023 08:56:43 GMT

OK, this indicates that the connection issues are not related to drift on the slow clock, which is one of the common reasons for the BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED error. Next thing I would suggest you try is to capture a sniffer trace of when you connect your phone or DK to the peripheral (Note that nRF52833 is not on the list of supported boards if you use our nRF Sniffer for Bluetooth LE). A sniffer trace will hopefully provide us with some additional clues.

If you do not have a Bluetooth sniffer, please test with one of the other SDK examples to find out if the connectivity issues may be FW related.

RE: Lots of BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED (0x3E) when using PCA10100

Julien — Thu, 05 Jan 2023 15:06:23 GMT

Hi,

I tried both (RC source and synthetized from HFCLK) but still the same issue

RE: Lots of BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED (0x3E) when using PCA10100

Vidar Berg — Tue, 27 Dec 2022 09:45:09 GMT

Hi,

To use the RC oscillator, you must specify a clock calibration interval and change the clock accuracy to 500 ppm. Otherwise, the Softdevice enable call with return with error 7 (invalid param). For this test, I suggest you select the synthesized clock source instead.

RE: Lots of BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED (0x3E) when using PCA10100

Julien — Thu, 22 Dec 2022 15:20:21 GMT

Hi Hung,

I am using an external 32 kHz crystal, but cannot use the RC clock source (error 7 when enable softdevice).

How can i verify the LFCLK or HFCLK?

RE: Lots of BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED (0x3E) when using PCA10100

Hung Bui — Thu, 22 Dec 2022 13:57:21 GMT

Hi Julien,

It's the same as BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED . Error 133 is a generic error number, and many time it's when the connection can't be established as I explained in the last reply.

If you still have good range, the clock source either LFCLK or HFCLK could be the issue . Please try to change the configuration to use RC clock source for the LFCLK if you are using external 32kHz crystal.

RE: Lots of BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED (0x3E) when using PCA10100

Julien — Thu, 22 Dec 2022 13:38:55 GMT

Hi Hung,

No range issue with a phone, but still difficulties to make connection (a lot of Error 133 (0x85): GATT ERROR)

devzone.nordicsemi.com/.../log_5F00_phone.txt

What is the meaning of this error ?

Best regards,

Julien

RE: Lots of BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED (0x3E) when using PCA10100

Hung Bui — Thu, 22 Dec 2022 12:29:58 GMT

Hi Julien,

The return code BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED happens when the central sends a connect request and assuming it's received by the peripheral. It will continue to send connect event packets according to the connection parameters to see if it get any response from the peripheral. After usually 6 packets without any response it will terminate the connection and return BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED .

This situation usually happens when the peripheral didn't receive the connect request or ignore it due to accept list (white list). Hence, no response from it to the central. In your case, it occasionally worked so it's more likely that it has something to do with the hardware on your board that the radio doesn't work as it should.

Have you tried to verify the behavior with another nRF52 Dev kit ? to see if you have the same BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED report or not ?

Do you have any range issue when you test your board with other central, for example a phone ?