Generate NCP firmware for UART with UART pins modified

[Bhumika]

I am using Nordic's NRF_SDK_For_Thread_and_Zigbee_4.1.0.

In that example/thread/ncp, I want to build NCP firmware for uart.

Original uart pins for rx and tx are 8 and 6.

While I want to build that firmware for pins 26 and 6.

UART Rx is 26 and Uart Tx is 4.

So where I should update these pins so that my custom nordic module, that has uart Rx on 26 and Tx on 4, can be interfaced with my custom gateway board, which I use as border router.

Also, should I add some Pullup or Pulldown to Rx pin in the NCP's main code?

nrf_gpio_cfg_input(0x1A, NRF_GPIO_PIN_PULLUP);

[Lukasz Duda]

Hello @Bhumika,

First of all in case you starting the new project I just want to recommend moving to our new SDK called nRF Connect SDK where you can find the NCP example as well - https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/samples/openthread/coprocessor/README.html

The nRF5 SDK for Thread and Zigbee is still supported but it is only in a maintenance mode, and OpenThread there is pretty much old there.

In case of nRF5 SDK for Thread and Zigbee the UART platform is placed in the pre-compiled OpenThread library, and so in order to change the pins, you need to regenerate libraries and replace them with ones from nRF5 SDK.

The instruction on how to generate libraries can be found here: https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/samples/openthread/coprocessor/README.html

Please however ensure that you checkout to the same revision of OpenThread from which the SDK was released:

git checkout c6a258e3a5bd90aa26d8245c435c0ae5797027f4

You can find the UART configuration in this file (and analogously for nRF52833 and nRF52811) - https://github.com/openthread/openthread/blob/c6a258e3a5bd90aa26d8245c435c0ae5797027f4/examples/platforms/nrf528xx/nrf52840/transport-config.h

After libraries will be generated, you don't need to copy them all, it's enough to copy libopenthread-nrf528xx-transport.a (in case you use GCC).