GPIOTE Set/Clr vs. Out task

[KWolfe81]

I would like to set a gpio pin on Radio RX Ready and clear it on Radio Disable all via PPI.  Below is my code. I only get the pin to change levels when the OUT task polarity is set to NRF_GPIOTE_POLARITY_TOGGLE.  Why is this?  I'm using the Set & Clear tasks explicitly, with nothing connected to the OUT task so my expectation is that this field shouldn't make a difference in operations but it does.

static const struct gpio_dt_spec test_pin = GPIO_DT_SPEC_GET(DT_ALIAS(test_pin), gpios);

nrfx_gpiote_init(0);
static uint8_t gpiote_channel;
nrfx_gpiote_channel_alloc(&gpiote_channel);

static const nrfx_gpiote_output_config_t output_config = {
    .drive = NRF_GPIO_PIN_S0S1,
    .input_connect = NRF_GPIO_PIN_INPUT_DISCONNECT,
    .pull = NRF_GPIO_PIN_NOPULL,
};
const nrfx_gpiote_task_config_t task_config = {
    .task_ch = gpiote_channel,
    .polarity = NRF_GPIOTE_POLARITY_TOGGLE,
    .init_val = 1,
};
nrfx_gpiote_output_configure(test_pin.pin, &output_config, &task_config);
nrfx_gpiote_out_task_enable(test_pin.pin);

nrf_ppi_channel_t ppi_channels[2];
nrfx_ppi_channel_alloc(&ppi_channels[0]);
nrfx_ppi_channel_alloc(&ppi_channels[1]);
nrfx_ppi_channel_assign(ppi_channels[0], nrf_radio_event_address_get(NRF_RADIO, NRF_RADIO_EVENT_RXREADY), nrfx_gpiote_set_task_addr_get(test_pin.pin));
nrfx_ppi_channel_assign(ppi_channels[1], nrf_radio_event_address_get(NRF_RADIO, NRF_RADIO_EVENT_DISABLED), nrfx_gpiote_clr_task_addr_get(test_pin.pin));
nrfx_ppi_channel_enable(ppi_channels[0]);
nrfx_ppi_channel_enable(ppi_channels[1]);

[Priyanka]

Hi Kevin,

Could you try to set the .polarity field to NRF_GPIO_POLARITY_NONE when you use the set and clear  tasks?

Please try this and let me know how it goes.

Regards,

Priyanka

[KWolfe81]

Worked perfectly fine.  And I see, taking a look at the nrfx_gpiote.c code why.  In nrfx_gpiote_output_configure(), there's the block:

        nrf_gpiote_te_default(NRF_GPIOTE, ch);
        m_cb.pin_flags[pin] &= ~(PIN_FLAG_TE_USED | PIN_TE_ID_MASK);
        if (p_task_config->polarity != NRF_GPIOTE_POLARITY_NONE)
        {
            nrf_gpiote_task_configure(NRF_GPIOTE, ch, pin,
                                      p_task_config->polarity,
                                      p_task_config->init_val);
            m_cb.pin_flags[pin] |= PIN_FLAG_TE_ID(ch);
        }
    }

That conditional if statement on the third line is stopping my setup.  Probably an oversight in the library, but at least it all makes sense. Thanks!