NCS - Devicetree & nrfx coexistence

[eyalasko]

Hi,

I have an application based on the "peripheral_uart" sample code (nRF52840DK, NCS2.70)

As I use interchangeably the same pins as GPIOs and UARTE1, I use UARTE1 with NRFX drivers:

nrfx_uarte_t uarte1_inst = NRFX_UARTE_INSTANCE(1)

This seems to work well.  Note that UARTE1 is not defined in the default devicetree file (nrf52840dk_nrf52840.dts) so I didn't modify app.overlay

My questions are -

1. What should I do if I want to use NRFX peripherals that ARE defined in the default dts file (specifically - TWIM0 & TWIM1)
   I added the following to prj.cnf

   CONFIG_I2C=y

   CONFIG_I2C_NRFX=y

   CONFIG_NRFX_TWI0=y

   CONFIG_NRFX_TWI1=y

   But I fail to instantiate TWI instance:

       nrfx_twim_t twim_inst = NRFX_TWIM_INSTANCE(0); // Macro expansion error

2. Is there a way to make a 'pure' NRFX project and get rid of all Devicetree references?

Thanks