NRF52 not able to establish a connection (0x3E)

[Tobi]

Hello guys,

Hope someone can help me here. I am working with the NRF52 and want to use Zephyr. I am able to flash it. Using the nrf52 as periphal does not cause problems, I can connect with it and exchange data. Using the nrf52 as central is not working. Starting from the central example provided by Zephyr (zephyr/samples/bluetooth/central/), I am able to scan and detecting a device successfully. Once a device is detected, a connection request is sent. This connection request terminates after the connection supervision timeout with the error 0x3E. I tried different intervals and different periphal devices but no connection is possible. Using a smartphone I could connect to all of those periphals so the problem is definitely located on the NRF52. I found here the information to add

CONFIG_CLOCK_CONTROL_NRF5_K32SRC_RC=y

CONFIG_CLOCK_CONTROL_NRF5_K32SRC_250PPM=y

to my prj.conf file. But it changes nothing. Also added it to zephyr/boards/arm/nrf52_pca10040/nrf52_pca10040_defconfig - no improvement.

So I really hope someone can give me a solution for this problem... thanks in advance!

[vich]

Hi Tobi,

If you have two nRF52 board, is the central_hr application connecting and receiving notification from a peripheral application?

Are you on the latest 1.8 release or on latest release? please provide the commit hash you are using wherein you see the problem. That said, please try the HEAD of the master branch ( github.com/.../zephyr )

Regards, Vinayak

[Tobi]

Thanks for your answer. The central and the central_hr application are not working. The central device and periphal device are logging to be connected but immediately after the connection gets disconnected with error 0x3E. I was following the "getting started guide" on the Zephyr webpage, installed Zephyr 2 or 3 weeks ago with SDK version 0.9.1. After your comment I deleted the old zephyr folder and reinstalled it. Seems this solved the problem. Establishing a connection is possible with the sample programs, using the nrf52 as central and as periphal. Thanks for your help!

[vich]

Tobi, You are welcome, happy to help.