nRF52840 SDK16 - How to use the nrfx PPI driver

RE: nRF52840 SDK16 - How to use the nrfx PPI driver

haakonsh — Mon, 06 Dec 2021 15:19:39 GMT

[quote user="Nikosant03"]If I set both to 1 it compiles fine. If I set PPI_ENABLED to 0 it cannot find the nrfx based functions. So, I guess every time I use the new implementation (nrfx drivers) I have to enable the legacy as well?[/quote]

Yes, that's what I've experienced at least.

[quote user="Nikosant03"]However, before commenting out it was working fine...[/quote]

All you did was to initialize the old driver without actually using it. So some RAM and flash is wasted, but it should not break anything i think.

RE: nRF52840 SDK16 - How to use the nrfx PPI driver

Nikosant03 — Mon, 06 Dec 2021 13:49:35 GMT

Hi haakonsh,

Thank you for your answer!!

[quote userid="13562" url="~/f/nordic-q-a/82408/nrf52840-sdk16---how-to-use-the-nrfx-ppi-driver/342078#342078"]No, there is no initialization/uninitialization functions in this API. You only need to allocate, assign, and enable a channel for it to work.[/quote]

So this is enough? I comment out the nrf_drv_ppi_init() function. However, before commenting out it was working fine...

static void ppi_init(void) {

  uint32_t err_code;
  uint32_t rtc_tick_event_addr;    // variable to hold the address of rtc event
  uint32_t saadc_sample_task_addr; // variable to hold the address of saadc task

  //err_code = nrf_drv_ppi_init(); // initialize the ppi module
  //APP_ERROR_CHECK(err_code);

  err_code = nrfx_ppi_channel_alloc(&m_ppi_channel); // allocate the channel. This function checks for the available channels and automatically allocates the channel
  APP_ERROR_CHECK(err_code);

  rtc_tick_event_addr = nrfx_rtc_event_address_get(&rtc, NRF_RTC_EVENT_TICK); // get the RTC event address
  saadc_sample_task_addr = nrf_drv_saadc_sample_task_get();                   // get the saadc task address

  err_code = nrfx_ppi_channel_assign(m_ppi_channel, rtc_tick_event_addr, saadc_sample_task_addr); // Assing event and task endpoints to the PPI channel
  APP_ERROR_CHECK(err_code);

  err_code = nrfx_ppi_channel_enable(m_ppi_channel); // Enable the PPI channel
  APP_ERROR_CHECK(err_code);
}

[quote userid="13562" url="~/f/nordic-q-a/82408/nrf52840-sdk16---how-to-use-the-nrfx-ppi-driver/342078#342078"]Hmm, do you you currently have an issue with building the new PPI driver? I'd start by setting both to 1, and if that does not work, set PPI_ENABLED to 0. [/quote]

If I set both to 1 it compiles fine. If I set PPI_ENABLED to 0 it cannot find the nrfx based functions. So, I guess every time I use the new implementation (nrfx drivers) I have to enable the legacy as well?

RE: nRF52840 SDK16 - How to use the nrfx PPI driver

haakonsh — Mon, 06 Dec 2021 13:22:44 GMT

[quote user=""]In the API reference of the PPI allocator there is no function for initialization. Should I use the legacy API nrf_drv_ppi_init()?[/quote]

No, there is no initialization/uninitialization functions in this API. You only need to allocate, assign, and enable a channel for it to work.

[quote user=""]Also, according to the following note should I keep both PPI_ENABLED and NRFX_PPI_ENABLED set to 1?[/quote]

Hmm, do you you currently have an issue with building the new PPI driver? I'd start by setting both to 1, and if that does not work, set PPI_ENABLED to 0.