SAADC callback

[RichieJH]

I have this working and producing good and accurate results, but I'm still puzzled by some of the examples in the SDK and the documentation.

I am using the processor to call for the saadc sample (i.e, not ppi) and I set the nrf_drv_saadc_buffer_converts immediately before hand:

err_code = nrf_drv_saadc_buffer_convert(m_buffer_pool[0], SAMPLES_IN_BUFFER);
err_code = nrf_drv_saadc_buffer_convert(m_buffer_pool[1], SAMPLES_IN_BUFFER);
err_code = nrf_drv_saadc_sample();

In the examples in the SDK (12) and elsewhere I also see another nrf_drv_saadc_buffer_convert call in the callback handler prior to reading the data in the buffer:

err_code = nrf_drv_saadc_buffer_convert(p_event->data.done.p_buffer, SAMPLES_IN_BUFFER);

My question is what is the point of calling this again in the call back and why is the first argument p_event->data.done.p_buffer? I've read the documentation but it still doesn't make sense to me. Could anyone explain this as if they are speaking to a 5 year old?

Many thanks,

[acha]

That's what I'm testing actually, the problem that I have a static error in one or ther channel, if I set for example 3.3 V in channel A, I have about 1.2V in the channel B, i the time the B channel is not connected :/

[acha]

there is my callback :

void adcHandler(nrf_drv_saadc_evt_t const *p_event) { if (p_event->type == NRF_DRV_SAADC_EVT_DONE) { nrf_drv_saadc_buffer_convert(p_event->data.done.p_buffer, SAMPLES_IN_BUFFER);

            adc_result = p_event->data.done.p_buffer[0];
            ptrFcnArray[0](adc_result); // Function which handles result in channel 0.
        
            adc_result = p_event->data.done.p_buffer[1];
            ptrFcnArray[1](adc_result); // Function which handles result in channel 1.           

            adc_result = p_event->data.done.p_buffer[2];
            ptrFcnArray[2](adc_result); // Function which handles result in channel 2.
}

}