Bluetooth: External radio coexistence using 1-wire interface

This sample demonstrates how to use the 1-wire coexistence feature described in Bluetooth® external radio coexistence.


The sample supports the following development kit:

Hardware platforms


Board name

Build target

nRF52840 DK





The application sets up an advertiser and configures the 1-wire coexistence feature. Enter g to grant or d to deny Bluetooth radio activity.

  • When Bluetooth radio activity is granted, packets are transmitted.

  • When Bluetooth radio activity is denied, no packets are transmitted.

  • The number of packets transmitted is tracked by counting the RADIO->READY event.

  • The total number of transmitted packets is printed every second.

The application generates a grant signal on the pin selected by coex-pta-grant-gpios. Connect this pin to the pin defined by the grant-gpios property in the DTS using a jumper cable.

On the nrf52840dk_nrf52840 target, the default pins are P0.26 and P0.02.

The board’s /zephyr,user node must have the coex-pta-grant-gpios property set in the devicetree. You can use this sample’s board overlay as an example.

Building and running

This sample can be found under samples/bluetooth/radio_coex_1wire in the nRF Connect SDK folder structure.

To build the sample with Visual Studio Code, follow the steps listed on the How to build an application page in the nRF Connect for VS Code extension documentation. See Building and programming an application for other building and programming scenarios and Testing and debugging an application for general information about testing and debugging in the nRF Connect SDK.


After programming the sample to your development kit, complete the following steps to test it:

  1. Build and program the development kit.

  2. Connect to the kit with a terminal emulator (for example, PuTTY). See How to connect with PuTTY for the required settings.

  3. Observe the number of packets transmitted.

  4. Enter d to deny packet transmission.

  5. Observe that packet transmissions have stopped.

  6. Enter g to grant packet transmission.

  7. Observe that packet transmissions have restarted.


This sample uses the following sdk-nrfxlib libraries:

It also uses drivers from the nrfx libraries.

It uses the following Zephyr libraries: