The Saadc of issue of uninit

Question

i init the saadc and uinit saadc ,then init saadc again. my code is below: 
 err_code = nrf_drv_saadc_init(NULL, saadc_callback); err_code = nrf_drv_saadc_channel_init(0, &channel_config_se1); err_code = nrf_drv_saadc_buffer_convert(m_buffer_pool, 1); 
 nrf_drv_saadc_uninit(); 
 err_code = nrf_drv_saadc_init(NULL, saadc_callback); err_code = nrf_drv_saadc_channel_init( 0 , &channel_config_se1); err_code = nrf_drv_saadc_buffer_convert(m_buffer_pool, 1 ); 
 from now .the err_code is correct . 
 But when i use nrf_drv_saadc_sample(), geting a error in SAADC_IRQHandler. And this is my callback: 
 void saadc_callback(nrf_drv_saadc_evt_t const * p_event) { if (p_event->type == NRF_DRV_SAADC_EVT_DONE) { nrf_drv_saadc_buffer_convert(m_buffer_pool，1); } 
 In SAADC_IRQHandler, the code enter in below: 
 if (nrf_saadc_event_check(NRF_SAADC_EVENT_STOPPED)) { nrf_saadc_event_clear(NRF_SAADC_EVENT_STOPPED); NRF_LOG_DEBUG("Event: %s.
", (uint32_t)EVT_TO_STR(NRF_SAADC_EVENT_STOPPED)); m_cb.adc_state = NRF_SAADC_STATE_IDLE; } 
 if i dont use nrf_drv_saadc_uninit(),there is greater. 
 what i can do???

Olaf · Answer

I guess the problem is inside the SAADC_IRQHandler. When using the uninit inside the callback there is a NRF_SAADC_EVENT_STOPPED event created. As the handling of the end event in line 117 (nRF5_SDK_12.3.0_d7731ad) is not terminating the IRQ function, the stop event is handled in line 190, setting the state of the driver to NRF_SAADC_STATE_IDLE after the reinit has been performed in the callback. The next call to nrf_drv_saadc_sample is then creating the invalid state error.

Solution: In SAADC_IRQHandler use else if to handle each kind of event:

void SAADC_IRQHandler(void)
{
    if (nrf_saadc_event_check(NRF_SAADC_EVENT_END))
    {
        nrf_saadc_event_clear(NRF_SAADC_EVENT_END);
        NRF_LOG_DEBUG("Event: %s.\r\n", (uint32_t)EVT_TO_STR(NRF_SAADC_EVENT_END));

        if (!m_cb.low_power_mode || m_cb.conversions_end)
        {
            nrf_drv_saadc_evt_t evt;
            evt.type               = NRF_DRV_SAADC_EVT_DONE;
            evt.data.done.p_buffer = (nrf_saadc_value_t *)m_cb.p_buffer;
            evt.data.done.size     = m_cb.buffer_size;

            if (m_cb.p_secondary_buffer == NULL)
            {
                m_cb.adc_state = NRF_SAADC_STATE_IDLE;
            }
            else
            {
                m_cb.buffer_size_left   = m_cb.secondary_buffer_size;
                m_cb.p_buffer           = m_cb.p_secondary_buffer;
                m_cb.buffer_size        = m_cb.secondary_buffer_size;
                m_cb.p_secondary_buffer = NULL;
                if (!m_cb.low_power_mode)
                {
                    nrf_saadc_task_trigger(NRF_SAADC_TASK_START);
                }
            }
            m_cb.event_handler(&evt);
            m_cb.conversions_end = false;
        }
    }
    else if (m_cb.low_power_mode && nrf_saadc_event_check(NRF_SAADC_EVENT_STARTED))
    {
        nrf_saadc_event_clear(NRF_SAADC_EVENT_STARTED);
        NRF_LOG_DEBUG("Event: %s.\r\n", (uint32_t)EVT_TO_STR(NRF_SAADC_EVENT_STARTED));

        if (m_cb.buffer_size_left > m_cb.active_channels)
        {
            // More samples to convert than for single event.
            m_cb.buffer_size_left -= m_cb.active_channels;
            nrf_saadc_buffer_init((nrf_saadc_value_t *)&m_cb.p_buffer[m_cb.buffer_size -
                                                                      m_cb.buffer_size_left],
                                  m_cb.active_channels);
        }
        else if ((m_cb.buffer_size_left == m_cb.active_channels) &&

                 (m_cb.p_secondary_buffer != NULL))
        {
            // Samples to convert for one event, prepare next buffer.
            m_cb.conversions_end  = true;
            m_cb.buffer_size_left = 0;
            nrf_saadc_buffer_init((nrf_saadc_value_t *)m_cb.p_secondary_buffer,
                                  m_cb.active_channels);
        }
        else if (m_cb.buffer_size_left == m_cb.active_channels)
        {
            // Samples to convert for one event, but no second buffer.
            m_cb.conversions_end  = true;
            m_cb.buffer_size_left = 0;
        }
        nrf_saadc_event_clear(NRF_SAADC_EVENT_END);
        nrf_saadc_task_trigger(NRF_SAADC_TASK_SAMPLE);
    }
    else if (nrf_saadc_event_check(NRF_SAADC_EVENT_CALIBRATEDONE))
    {
        nrf_saadc_event_clear(NRF_SAADC_EVENT_CALIBRATEDONE);
        NRF_LOG_DEBUG("Event: %s.\r\n", (uint32_t)EVT_TO_STR(NRF_SAADC_EVENT_CALIBRATEDONE));
        m_cb.adc_state = NRF_SAADC_STATE_IDLE;

        nrf_drv_saadc_evt_t evt;
        evt.type = NRF_DRV_SAADC_EVT_CALIBRATEDONE;
        m_cb.event_handler(&evt);
    }
    else if (nrf_saadc_event_check(NRF_SAADC_EVENT_STOPPED))
    {
        nrf_saadc_event_clear(NRF_SAADC_EVENT_STOPPED);
        NRF_LOG_DEBUG("SAADC IRQ -- Event: %s.\r\n", (uint32_t)EVT_TO_STR(NRF_SAADC_EVENT_STOPPED));
        m_cb.adc_state = NRF_SAADC_STATE_IDLE;
    }
    else
    {
        uint32_t          limit_flags = m_cb.limits_enabled_flags;
        uint32_t          flag_idx;
        nrf_saadc_event_t event;

        while (limit_flags)
        {
            flag_idx     = __CLZ(limit_flags);
            limit_flags &= ~((1UL << 31) >> flag_idx);
            event        = FLAG_IDX_TO_EVENT(flag_idx);
            if (nrf_saadc_event_check(event))
            {
                nrf_saadc_event_clear(event);
                nrf_drv_saadc_evt_t evt;
                evt.type                  = NRF_DRV_SAADC_EVT_LIMIT;
                evt.data.limit.channel    = LIMIT_EVENT_TO_CHANNEL(event);
                evt.data.limit.limit_type = LIMIT_EVENT_TO_LIMIT_TYPE(event);
                NRF_LOG_DEBUG("Event limit, channel: %d, limit type: %s.\r\n", evt.data.limit.channel, (uint32_t)EVT_TO_STR(evt.data.limit.limit_type));
                m_cb.event_handler(&evt);
            }
        }
    }
}