software_knock.h File Reference

Data Structures
struct	SpectrogramData

Functions
void	initSoftwareKnock ()
void	knockSamplingCallback (uint8_t cylinderIndex, efitick_t nowNt)

Function Documentation

initSoftwareKnock()

void initSoftwareKnock

(

)

Definition at line 91 of file software_knock.cpp.

                         {
    if (engineConfiguration->enableSoftwareKnock) {
 
        float frequencyHz = 1000 * bore2frequency(engineConfiguration->cylinderBore);
        frequencyHz = engineConfiguration->knockDetectionUseDoubleFrequency ? 2 * frequencyHz : frequencyHz;
 
        if (engineConfiguration->knockFrequency > 0.01) {
            frequencyHz = engineConfiguration->knockFrequency;
        }
 
        knockFilter.configureBandpass(KNOCK_SAMPLE_RATE, frequencyHz, 3);
 
    #ifdef KNOCK_SPECTROGRAM
        if (engineConfiguration->enableKnockSpectrogram) {
 
            // TODO: use big buffer
            //buffer = getBigBuffer(BigBufferUser::KnockSpectrogram);
            // if (!buffer) {
            //  engineConfiguration->enableKnockSpectrogram = false;
            //      return;
            //  }
            //spectrogramData = buffer.get<SpectrogramData>();
 
            fft::blackmanharris(spectrogramData->window, FFT_SIZE, true);
 
            int freqStartConst = START_SPECTRORGAM_FREQUENCY;
            int minFreqDiff = freqStartConst;
            int freqStart = 0;
            float freqStep = 0;
 
            for (size_t i = 0; i < FFT_SIZE/2; i++)
            {
                float freq = float(i * KNOCK_SAMPLE_RATE) / FFT_SIZE;
                int min = abs(freq - freqStartConst);
 
                // next after freq start index
                if(i == spectrogramStartIndex + 1) {
                    freqStep = abs(freq - freqStart);
                }
 
                if(min < minFreqDiff) {
                    minFreqDiff = min;
                    spectrogramStartIndex = i;
                    freqStart = freq;
                }
            }
 
            engine->module<KnockController>()->m_knockFrequencyStart = (uint16_t)freqStart;
            engine->module<KnockController>()->m_knockFrequencyStep = freqStep;
        }
    #endif
 
  // fun fact: we do not offer any ADC channel flexibility like we have for many other kinds of inputs
        efiSetPadMode("knock ch1", KNOCK_PIN_CH1, PAL_MODE_INPUT_ANALOG);
#if KNOCK_HAS_CH2
        efiSetPadMode("knock ch2", KNOCK_PIN_CH2, PAL_MODE_INPUT_ANALOG);
#endif
        kt.start();
    }
}

Referenced by initHardware().

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knockSamplingCallback()

void knockSamplingCallback	(	uint8_t	cylinderIndex,
		efitick_t	nowNt
	)

Go to the source code of this file.