SPIM/UARTE register conflict with hal_nordic

RE: SPIM/UARTE register conflict with hal_nordic

Jørgen Holmefjord — Thu, 08 Apr 2021 16:50:07 GMT

Yes, you should make sure to set p_config->dcx_pin == NRFX_SPIM_PIN_NOT_USED for all other instances than SPIM4, then the init function should not change this and make issues for the UARTE instances using this register.

The uninit-function seems to contain a bug, and is something we should handle better. Previous chips have not had these issues, as nRF52 series ICs had separate base addresses for UART(E) instances (not shared with SPI/TWI), and nRF91 did not include the 32MHz high-speed SPI instance, so there was no DCX support at all. I will report this issue to our developers to get it fixed in future releases of NRFX.

RE: SPIM/UARTE register conflict with hal_nordic

Stephan Walter — Wed, 07 Apr 2021 08:24:59 GMT

Hi Jørgen,

thanks for the quick response.

So leaving PSELDCX at 0 for SPIM0 to SPIM3 is ok, I assume?

In any case there is still a problem in the function nrfx_spim_uninit:

https://github.com/zephyrproject-rtos/hal_nordic/blob/fc301b97581d01cb5be47f837087a41632070434/nrfx/drivers/src/nrfx_spim.c#L472

It will call nrf_gpio_cfg_default(0).

RE: SPIM/UARTE register conflict with hal_nordic

Jørgen Holmefjord — Wed, 07 Apr 2021 08:12:08 GMT

Hi,

DCX functionality is only supported in SPIM4 (32 MHz High-speed instance), see "Configuration" column next to each instance in Registers. SPIM4 does not share any resources with UARTE, as there is no UARTE4 instance, see Peripheral instantiation.

You should not enable DCX for other instances of SPIM when initializing the SPIM driver.

Best regards,
Jørgen