trigger_central.cpp

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/*
 * @file    trigger_central.cpp
 * Here we have a bunch of higher-level methods which are not directly related to actual signal decoding
 *
 * @date Feb 23, 2014
 * @author Andrey Belomutskiy, (c) 2012-2020
 */
 
#include "pch.h"
 
#include "trigger_central.h"
#include "trigger_decoder.h"
#include "main_trigger_callback.h"
#include "listener_array.h"
#include "hip9011.h"
#include "logic_analyzer.h"
 
#include "local_version_holder.h"
#include "trigger_simulator.h"
#include "trigger_emulator_algo.h"
 
#include "map_averaging.h"
#include "main_trigger_callback.h"
#include "status_loop.h"
#include "engine_sniffer.h"
#include "auto_generated_sync_edge.h"
 
#if EFI_TUNER_STUDIO
#include "tunerstudio.h"
#endif /* EFI_TUNER_STUDIO */
 
#if EFI_ENGINE_SNIFFER
WaveChart waveChart;
#endif /* EFI_ENGINE_SNIFFER */
 
static scheduling_s debugToggleScheduling;
#define DEBUG_PIN_DELAY US2NT(60)
 
#define TRIGGER_WAVEFORM(x) getTriggerCentral()->triggerShape.x
 
#if EFI_SHAFT_POSITION_INPUT
 
TriggerCentral::TriggerCentral() :
        vvtEventRiseCounter(),
        vvtEventFallCounter(),
        vvtPosition(),
        triggerState("TRG")
{
    memset(&hwEventCounters, 0, sizeof(hwEventCounters));
    triggerState.resetState();
    noiseFilter.resetAccumSignalData();
}
 
void TriggerNoiseFilter::resetAccumSignalData() {
    memset(lastSignalTimes, 0xff, sizeof(lastSignalTimes)); // = -1
    memset(accumSignalPeriods, 0, sizeof(accumSignalPeriods));
    memset(accumSignalPrevPeriods, 0, sizeof(accumSignalPrevPeriods));
}
 
int TriggerCentral::getHwEventCounter(int index) const {
    return hwEventCounters[index];
}
 
 
angle_t TriggerCentral::getVVTPosition(uint8_t bankIndex, uint8_t camIndex) {
    if (bankIndex >= BANKS_COUNT || camIndex >= CAMS_PER_BANK) {
        return NAN;
    }
    return vvtPosition[bankIndex][camIndex];
}
 
/**
 * @return angle since trigger synchronization point, NOT angle since TDC.
 */
expected<float> TriggerCentral::getCurrentEnginePhase(efitick_t nowNt) const {
    floatus_t oneDegreeUs = engine->rpmCalculator.oneDegreeUs;
 
    if (cisnan(oneDegreeUs)) {
        return unexpected;
    }
 
    float elapsed;
    float toothPhase;
 
    {
        // under lock to avoid mismatched tooth phase and time
        chibios_rt::CriticalSectionLocker csl;
 
        elapsed = m_lastToothTimer.getElapsedUs(nowNt);
        toothPhase = m_lastToothPhaseFromSyncPoint;
    }
 
    return toothPhase + elapsed / oneDegreeUs;
}
 
/**
 * todo: why is this method NOT reciprocal to getRpmMultiplier?!
 */
int getCrankDivider(operation_mode_e operationMode) {
    switch (operationMode) {
    case FOUR_STROKE_CRANK_SENSOR:
        return 2;
    case FOUR_STROKE_SYMMETRICAL_CRANK_SENSOR:
        return SYMMETRICAL_CRANK_SENSOR_DIVIDER;
    case FOUR_STROKE_THREE_TIMES_CRANK_SENSOR:
        return SYMMETRICAL_THREE_TIMES_CRANK_SENSOR_DIVIDER;
    case FOUR_STROKE_SIX_TIMES_CRANK_SENSOR:
        return SYMMETRICAL_SIX_TIMES_CRANK_SENSOR_DIVIDER;
    case FOUR_STROKE_TWELVE_TIMES_CRANK_SENSOR:
        return SYMMETRICAL_TWELVE_TIMES_CRANK_SENSOR_DIVIDER;
    case OM_NONE:
    case FOUR_STROKE_CAM_SENSOR:
    case TWO_STROKE:
        // That's easy - trigger cycle matches engine cycle
        return 1;
    /* let's NOT handle default in order to benefit from -Werror=switch */
    }
    /**
     wow even while we explicitly handle all enumerations in the switch above we still need a return statement due to
     https://stackoverflow.com/questions/34112483/gcc-how-best-to-handle-warning-about-unreachable-end-of-function-after-switch
     */
    criticalError("unreachable getCrankDivider");
    return 1;
}
 
static bool vvtWithRealDecoder(vvt_mode_e vvtMode) {
    return vvtMode != VVT_INACTIVE
            && vvtMode != VVT_TOYOTA_3_TOOTH /* VVT_2JZ is an unusual 3/0 missed tooth symmetrical wheel */
            && vvtMode != VVT_HONDA_K_INTAKE
            && vvtMode != VVT_MAP_V_TWIN
            && vvtMode != VVT_SINGLE_TOOTH;
}
 
angle_t TriggerCentral::syncEnginePhaseAndReport(int divider, int remainder) {
    angle_t engineCycle = getEngineCycle(getEngineRotationState()->getOperationMode());
 
    angle_t totalShift = triggerState.syncEnginePhase(divider, remainder, engineCycle);
    if (totalShift != 0) {
        // Reset instant RPM, since the engine phase has now changed, invalidating the tooth history buffer
        // maybe TODO: could/should we rotate the buffer around to re-align it instead? Is that worth it?
        instantRpm.resetInstantRpm();
    }
    return totalShift;
}
 
static void turnOffAllDebugFields(void *arg) {
    (void)arg;
#if EFI_PROD_CODE
    for (int index = 0;index<TRIGGER_INPUT_PIN_COUNT;index++) {
        if (isBrainPinValid(engineConfiguration->triggerInputDebugPins[index])) {
            writePad("trigger debug", engineConfiguration->triggerInputDebugPins[index], 0);
        }
    }
    for (int index = 0;index<CAM_INPUTS_COUNT;index++) {
        if (isBrainPinValid(engineConfiguration->camInputsDebug[index])) {
            writePad("cam debug", engineConfiguration->camInputsDebug[index], 0);
        }
    }
#endif /* EFI_PROD_CODE */
}
 
static angle_t adjustCrankPhase(int camIndex) {
    float maxSyncThreshold = engineConfiguration->maxCamPhaseResolveRpm;
    if (maxSyncThreshold != 0 && Sensor::getOrZero(SensorType::Rpm) > maxSyncThreshold) {
        // The user has elected to stop trying to resolve crank phase after some RPM.
        // Maybe their cam sensor only works at low RPM or something.
        // Anyway, don't try to change crank phase at all, and return that we made no change.
        return 0;
    }
 
    operation_mode_e operationMode = getEngineRotationState()->getOperationMode();
 
    auto crankDivider = getCrankDivider(operationMode);
    if (crankDivider == 1) {
        // Crank divider of 1 means there's no ambiguity, so don't try to resolve it
        return 0;
    }
 
    TriggerCentral *tc = getTriggerCentral();
 
    vvt_mode_e vvtMode = engineConfiguration->vvtMode[camIndex];
    switch (vvtMode) {
    case VVT_MAP_V_TWIN:
    case VVT_MITSUBISHI_4G63:
    case VVT_MITSUBISHI_4G9x:
        return tc->syncEnginePhaseAndReport(crankDivider, 1);
    case VVT_SINGLE_TOOTH:
    case VVT_NISSAN_VQ:
    case VVT_BOSCH_QUICK_START:
    case VVT_MIATA_NB:
    case VVT_TOYOTA_3_TOOTH:
    case VVT_TOYOTA_4_1:
    case VVT_FORD_COYOTE:
    case VVT_FORD_ST170:
    case VVT_BARRA_3_PLUS_1:
    case VVT_NISSAN_MR:
    case VVT_MAZDA_SKYACTIV:
    case VVT_MITSUBISHI_4G69:
    case VVT_MITSUBISHI_3A92:
    case VVT_MITSUBISHI_6G72:
    case VVT_MITSUBISHI_6G75:
    case VVT_HONDA_K_EXHAUST:
    case VVT_HONDA_CBR_600:
        return tc->syncEnginePhaseAndReport(crankDivider, 0);
    case VVT_HONDA_K_INTAKE:
        // with 4 evenly spaced tooth we cannot use this wheel for engine sync
        criticalError("Honda K Intake is not suitable for engine sync");
        [[fallthrough]];
    case VVT_INACTIVE:
        // do nothing
        return 0;
    }
    return 0;
}
 
/**
 * See also wrapAngle
 */
static angle_t wrapVvt(angle_t vvtPosition, int period) {
    // Wrap VVT position in to the range [-360, 360)
    while (vvtPosition < -period / 2) {
        vvtPosition += period;
    }
    while (vvtPosition >= period / 2) {
        vvtPosition -= period;
    }
    return vvtPosition;
}
 
static void logVvtFront(bool useOnlyRise, bool isImportantFront, TriggerValue front, efitick_t nowNt, int index) {
    if (isImportantFront && isBrainPinValid(engineConfiguration->camInputsDebug[index])) {
#if EFI_PROD_CODE
        writePad("cam debug", engineConfiguration->camInputsDebug[index], 1);
#endif /* EFI_PROD_CODE */
        getExecutorInterface()->scheduleByTimestampNt("dbg_on", &debugToggleScheduling, nowNt + DEBUG_PIN_DELAY, &turnOffAllDebugFields);
    }
 
    if (!useOnlyRise || engineConfiguration->displayLogicLevelsInEngineSniffer) {
        // If we care about both edges OR displayLogicLevel is set, log every front exactly as it is
        addEngineSnifferVvtEvent(index, front == TriggerValue::RISE ? FrontDirection::UP : FrontDirection::DOWN);
 
#if EFI_TOOTH_LOGGER
        LogTriggerTooth(front == TriggerValue::RISE ? SHAFT_SECONDARY_RISING : SHAFT_SECONDARY_FALLING, nowNt);
#endif /* EFI_TOOTH_LOGGER */
    } else {
        if (isImportantFront) {
            // On the important edge, log a rise+fall pair, and nothing on the real falling edge
            addEngineSnifferVvtEvent(index, FrontDirection::UP);
            addEngineSnifferVvtEvent(index, FrontDirection::DOWN);
 
#if EFI_TOOTH_LOGGER
            LogTriggerTooth(SHAFT_SECONDARY_RISING, nowNt);
            LogTriggerTooth(SHAFT_SECONDARY_FALLING, nowNt);
#endif /* EFI_TOOTH_LOGGER */
        }
    }
}
 
void hwHandleVvtCamSignal(bool isRising, efitick_t timestamp, int index) {
    hwHandleVvtCamSignal(isRising ? TriggerValue::RISE : TriggerValue::FALL, timestamp, index);
}
 
// 'invertCamVVTSignal' is already accounted by the time this method is invoked
void hwHandleVvtCamSignal(TriggerValue front, efitick_t nowNt, int index) {
    TriggerCentral *tc = getTriggerCentral();
    if (tc->directSelfStimulation || !tc->hwTriggerInputEnabled) {
        // sensor noise + self-stim = loss of trigger sync
        return;
    }
    handleVvtCamSignal(front, nowNt, index);
}
 
void handleVvtCamSignal(TriggerValue front, efitick_t nowNt, int index) {
    TriggerCentral *tc = getTriggerCentral();
    if (index == 0) {
        engine->outputChannels.vvtChannel1 = front == TriggerValue::RISE;
    } else if (index == 1) {
        engine->outputChannels.vvtChannel2 = front == TriggerValue::RISE;
    } else if (index == 2) {
        engine->outputChannels.vvtChannel3 = front == TriggerValue::RISE;
    } else if (index == 3) {
        engine->outputChannels.vvtChannel4 = front == TriggerValue::RISE;
    }
 
    int bankIndex = BANK_BY_INDEX(index);
    int camIndex = CAM_BY_INDEX(index);
    if (front == TriggerValue::RISE) {
        tc->vvtEventRiseCounter[index]++;
    } else {
        tc->vvtEventFallCounter[index]++;
    }
    if (engineConfiguration->vvtMode[camIndex] == VVT_INACTIVE) {
        warning(ObdCode::CUSTOM_VVT_MODE_NOT_SELECTED, "VVT: event on %d but no mode", camIndex);
    }
 
#ifdef VR_HW_CHECK_MODE
    // some boards do not have hardware VR input LEDs which makes such boards harder to validate
    // from experience we know that assembly mistakes happen and quality control is required
    extern ioportid_t criticalErrorLedPort;
    extern ioportmask_t criticalErrorLedPin;
 
    for (int i = 0 ; i < 100 ; i++) {
        // turning pin ON and busy-waiting a bit
        palWritePad(criticalErrorLedPort, criticalErrorLedPin, 1);
    }
 
    palWritePad(criticalErrorLedPort, criticalErrorLedPin, 0);
#endif // VR_HW_CHECK_MODE
 
    const auto& vvtShape = tc->vvtShape[camIndex];
 
    bool isVvtWithRealDecoder = vvtWithRealDecoder(engineConfiguration->vvtMode[camIndex]);
 
    // Non real decoders only use the rising edge
    bool vvtUseOnlyRise = !isVvtWithRealDecoder || vvtShape.useOnlyRisingEdges;
    bool isImportantFront = !vvtUseOnlyRise || (front == TriggerValue::RISE);
 
    logVvtFront(vvtUseOnlyRise, isImportantFront, front, nowNt, index);
 
    if (!isImportantFront) {
        // This edge is unimportant, ignore it.
        return;
    }
 
    // If the main trigger is not synchronized, don't decode VVT yet
    if (!tc->triggerState.getShaftSynchronized()) {
        return;
    }
 
    TriggerDecoderBase& vvtDecoder = tc->vvtState[bankIndex][camIndex];
 
    if (isVvtWithRealDecoder) {
        vvtDecoder.decodeTriggerEvent(
                "vvt",
            vvtShape,
            nullptr,
            tc->vvtTriggerConfiguration[camIndex],
            front == TriggerValue::RISE ? SHAFT_PRIMARY_RISING : SHAFT_PRIMARY_FALLING, nowNt);
        // yes we log data from all VVT channels into same fields for now
        tc->triggerState.vvtSyncGapRatio = vvtDecoder.triggerSyncGapRatio;
        tc->triggerState.vvtToothDurations0 = (uint32_t)NT2US(vvtDecoder.toothDurations[0]);
        tc->triggerState.vvtStateIndex = vvtDecoder.currentCycle.current_index;
    }
 
    // here we count all cams together
    tc->vvtCamCounter++;
 
    auto currentPhase = tc->getCurrentEnginePhase(nowNt);
    if (!currentPhase) {
        // If we couldn't resolve engine speed (yet primary trigger is sync'd), this
        // probably means that we have partial crank sync, but not RPM information yet
        return;
    }
 
    angle_t angleFromPrimarySyncPoint = currentPhase.Value;
    // convert trigger cycle angle into engine cycle angle
    angle_t currentPosition = angleFromPrimarySyncPoint - tdcPosition();
    // https://github.com/rusefi/rusefi/issues/1713 currentPosition could be negative that's expected
 
#if EFI_UNIT_TEST
    tc->currentVVTEventPosition[bankIndex][camIndex] = currentPosition;
#endif // EFI_UNIT_TEST
 
    tc->triggerState.vvtCurrentPosition = currentPosition;
 
    if (isVvtWithRealDecoder && vvtDecoder.currentCycle.current_index != 0) {
        // this is not sync tooth - exiting
        return;
    }
 
    auto vvtPosition = engineConfiguration->vvtOffsets[bankIndex * CAMS_PER_BANK + camIndex] - currentPosition;
    tc->triggerState.vvtToothPosition[index] = vvtPosition;
 
    switch(engineConfiguration->vvtMode[camIndex]) {
    case VVT_TOYOTA_3_TOOTH:
    {
        int from = engineConfiguration->camDecoder2jzPosition - engineConfiguration->camDecoder2jzPrecision;
        int to   = engineConfiguration->camDecoder2jzPosition + engineConfiguration->camDecoder2jzPrecision;
        // we do not know if we are in sync or out of sync, so we have to be looking for both possibilities
        if ((currentPosition < from       || currentPosition > to) &&
            (currentPosition < from + 360 || currentPosition > to + 360)) {
            // outside of the expected range
            return;
        }
    }
        break;
    default:
        // else, do nothing
        break;
    }
 
    // this could be just an 'if' but let's have it expandable for future use :)
    switch(engineConfiguration->vvtMode[camIndex]) {
    case VVT_HONDA_K_INTAKE:
        // honda K has four tooth in VVT intake trigger, so we just wrap each of those to 720 / 4
        vvtPosition = wrapVvt(vvtPosition, 180);
        break;
    default:
        // else, do nothing
        break;
    }
 
    // Only do engine sync using one cam, other cams just provide VVT position.
    if (index == engineConfiguration->engineSyncCam) {
        angle_t crankOffset = adjustCrankPhase(camIndex);
        // vvtPosition was calculated against wrong crank zero position. Now that we have adjusted crank position we
        // shall adjust vvt position as well
        vvtPosition -= crankOffset;
        vvtPosition = wrapVvt(vvtPosition, FOUR_STROKE_CYCLE_DURATION);
 
        if (absF(angleFromPrimarySyncPoint) < 7) {
            /**
             * we prefer not to have VVT sync right at trigger sync so that we do not have phase detection error if things happen a bit in
             * wrong order due to belt flex or else
             * https://github.com/rusefi/rusefi/issues/3269
             */
            warning(ObdCode::CUSTOM_VVT_SYNC_POSITION, "VVT sync position too close to trigger sync");
        }
    } else {
        // Not using this cam for engine sync, just wrap the value in to the reasonable range
        vvtPosition = wrapVvt(vvtPosition, FOUR_STROKE_CYCLE_DURATION);
    }
 
    // Only record VVT position if we have full engine sync - may be bogus before that point
    if (tc->triggerState.hasSynchronizedPhase()) {
        tc->vvtPosition[bankIndex][camIndex] = vvtPosition;
    } else {
        tc->vvtPosition[bankIndex][camIndex] = 0;
    }
}
 
int triggerReentrant = 0;
int maxTriggerReentrant = 0;
uint32_t triggerDuration;
uint32_t triggerMaxDuration = 0;
 
/**
 * This function is called by all "hardware" trigger inputs:
 *  - Hardware triggers
 *  - Trigger replay from CSV (unit tests)
 */
void hwHandleShaftSignal(int signalIndex, bool isRising, efitick_t timestamp) {
    TriggerCentral *tc = getTriggerCentral();
    ScopePerf perf(PE::HandleShaftSignal);
#ifdef VR_HW_CHECK_MODE
    // some boards do not have hardware VR input LEDs which makes such boards harder to validate
    // from experience we know that assembly mistakes happen and quality control is required
    extern ioportid_t criticalErrorLedPort;
    extern ioportmask_t criticalErrorLedPin;
 
#if HW_CHECK_ALWAYS_STIMULATE
    disableTriggerStimulator();
#endif // HW_CHECK_ALWAYS_STIMULATE
 
 
    for (int i = 0 ; i < 100 ; i++) {
        // turning pin ON and busy-waiting a bit
        palWritePad(criticalErrorLedPort, criticalErrorLedPin, 1);
    }
 
    palWritePad(criticalErrorLedPort, criticalErrorLedPin, 0);
#endif // VR_HW_CHECK_MODE
 
    if (tc->directSelfStimulation || !tc->hwTriggerInputEnabled) {
        // sensor noise + self-stim = loss of trigger sync
        return;
    }
 
    handleShaftSignal(signalIndex, isRising, timestamp);
}
 
// Handle all shaft signals - hardware or emulated both
void handleShaftSignal(int signalIndex, bool isRising, efitick_t timestamp) {
    bool isPrimary = signalIndex == 0;
    if (!isPrimary && !TRIGGER_WAVEFORM(needSecondTriggerInput)) {
        return;
    }
 
    trigger_event_e signal;
    // todo: add support for 3rd channel
    if (isRising) {
        signal = isPrimary ?
                    (engineConfiguration->invertPrimaryTriggerSignal ? SHAFT_PRIMARY_FALLING : SHAFT_PRIMARY_RISING) :
                    (engineConfiguration->invertSecondaryTriggerSignal ? SHAFT_SECONDARY_FALLING : SHAFT_SECONDARY_RISING);
    } else {
        signal = isPrimary ?
                    (engineConfiguration->invertPrimaryTriggerSignal ? SHAFT_PRIMARY_RISING : SHAFT_PRIMARY_FALLING) :
                    (engineConfiguration->invertSecondaryTriggerSignal ? SHAFT_SECONDARY_RISING : SHAFT_SECONDARY_FALLING);
    }
    if (isPrimary) {
        engine->outputChannels.triggerChannel1 = signal == SHAFT_PRIMARY_RISING;
    } else {
        engine->outputChannels.triggerChannel2 = signal == SHAFT_SECONDARY_RISING;
    }
 
    // Don't accept trigger input in case of some problems
    if (!getLimpManager()->allowTriggerInput()) {
        return;
    }
 
#if EFI_TOOTH_LOGGER
    // Log to the Tunerstudio tooth logger
    // We want to do this before anything else as we
    // actually want to capture any noise/jitter that may be occurring
 
    bool logLogicState = engineConfiguration->displayLogicLevelsInEngineSniffer && getTriggerCentral()->triggerShape.useOnlyRisingEdges;
 
    if (!logLogicState) {
        // we log physical state even if displayLogicLevelsInEngineSniffer if both fronts are used by decoder
        LogTriggerTooth(signal, timestamp);
    }
 
#endif /* EFI_TOOTH_LOGGER */
 
    // for effective noise filtering, we need both signal edges,
    // so we pass them to handleShaftSignal() and defer this test
    if (!engineConfiguration->useNoiselessTriggerDecoder) {
        if (!isUsefulSignal(signal, getTriggerCentral()->triggerShape)) {
            /**
             * no need to process VR falls further
             */
            return;
        }
    }
 
    if (engineConfiguration->triggerInputDebugPins[signalIndex] != Gpio::Unassigned) {
#if EFI_PROD_CODE
        writePad("trigger debug", engineConfiguration->triggerInputDebugPins[signalIndex], 1);
#endif /* EFI_PROD_CODE */
        getExecutorInterface()->scheduleByTimestampNt("dbg_off", &debugToggleScheduling, timestamp + DEBUG_PIN_DELAY, &turnOffAllDebugFields);
    }
 
#if EFI_TOOTH_LOGGER
    if (logLogicState) {
        // first log rising normally
        LogTriggerTooth(signal, timestamp);
        // in 'logLogicState' mode we log opposite front right after logical rising away
        if (signal == SHAFT_PRIMARY_RISING) {
            LogTriggerTooth(SHAFT_PRIMARY_FALLING, timestamp);
        } else {
            LogTriggerTooth(SHAFT_SECONDARY_FALLING, timestamp);
        }
    }
#endif /* EFI_TOOTH_LOGGER */
 
    uint32_t triggerHandlerEntryTime = getTimeNowLowerNt();
    if (triggerReentrant > maxTriggerReentrant)
        maxTriggerReentrant = triggerReentrant;
    triggerReentrant++;
 
    getTriggerCentral()->handleShaftSignal(signal, timestamp);
 
    triggerReentrant--;
    triggerDuration = getTimeNowLowerNt() - triggerHandlerEntryTime;
    triggerMaxDuration = maxI(triggerMaxDuration, triggerDuration);
}
 
void TriggerCentral::resetCounters() {
    memset(hwEventCounters, 0, sizeof(hwEventCounters));
}
 
static const bool isUpEvent[4] = { false, true, false, true };
static const int wheelIndeces[4] = { 0, 0, 1, 1};
 
static void reportEventToWaveChart(trigger_event_e ckpSignalType, int triggerEventIndex, bool addOppositeEvent) {
    if (!getTriggerCentral()->isEngineSnifferEnabled) { // this is here just as a shortcut so that we avoid engine sniffer as soon as possible
        return; // engineSnifferRpmThreshold is accounted for inside getTriggerCentral()->isEngineSnifferEnabled
    }
 
    int wheelIndex = wheelIndeces[(int )ckpSignalType];
 
    bool isUp = isUpEvent[(int) ckpSignalType];
 
    addEngineSnifferCrankEvent(wheelIndex, triggerEventIndex, isUp ? FrontDirection::UP : FrontDirection::DOWN);
    if (addOppositeEvent) {
        // let's add the opposite event right away
        addEngineSnifferCrankEvent(wheelIndex, triggerEventIndex, isUp ? FrontDirection::DOWN : FrontDirection::UP);
    }
}
 
/**
 * This is used to filter noise spikes (interference) in trigger signal. See
 * The basic idea is to use not just edges, but the average amount of time the signal stays in '0' or '1'.
 * So we update 'accumulated periods' to track where the signal is.
 * And then compare between the current period and previous, with some tolerance (allowing for the wheel speed change).
 * @return true if the signal is passed through.
 */
bool TriggerNoiseFilter::noiseFilter(efitick_t nowNt,
        TriggerDecoderBase * triggerState,
        trigger_event_e signal) {
    // todo: find a better place for these defs
    static const trigger_event_e opposite[4] = { SHAFT_PRIMARY_RISING, SHAFT_PRIMARY_FALLING, SHAFT_SECONDARY_RISING, SHAFT_SECONDARY_FALLING };
    static const TriggerWheel triggerIdx[4] = { TriggerWheel::T_PRIMARY, TriggerWheel::T_PRIMARY, TriggerWheel::T_SECONDARY, TriggerWheel:: T_SECONDARY };
    // we process all trigger channels independently
    TriggerWheel ti = triggerIdx[signal];
    // falling is opposite to rising, and vise versa
    trigger_event_e os = opposite[signal];
 
    // todo: currently only primary channel is filtered, because there are some weird trigger types on other channels
    if (ti != TriggerWheel::T_PRIMARY)
        return true;
 
    // update period accumulator: for rising signal, we update '0' accumulator, and for falling - '1'
    if (lastSignalTimes[signal] != -1)
        accumSignalPeriods[signal] += nowNt - lastSignalTimes[signal];
    // save current time for this trigger channel
    lastSignalTimes[signal] = nowNt;
 
    // now we want to compare current accumulated period to the stored one
    efitick_t currentPeriod = accumSignalPeriods[signal];
    // the trick is to compare between different
    efitick_t allowedPeriod = accumSignalPrevPeriods[os];
 
    // but first check if we're expecting a gap
    bool isGapExpected = TRIGGER_WAVEFORM(isSynchronizationNeeded) && triggerState->getShaftSynchronized() &&
            (triggerState->currentCycle.eventCount[(int)ti] + 1) == TRIGGER_WAVEFORM(getExpectedEventCount(ti));
 
    if (isGapExpected) {
        // usually we need to extend the period for gaps, based on the trigger info
        allowedPeriod *= TRIGGER_WAVEFORM(syncRatioAvg);
    }
 
    // also we need some margin for rapidly changing trigger-wheel speed,
    // that's why we expect the period to be no less than 2/3 of the previous period (this is just an empirical 'magic' coef.)
    efitick_t minAllowedPeriod = 2 * allowedPeriod / 3;
    // but no longer than 5/4 of the previous 'normal' period
    efitick_t maxAllowedPeriod = 5 * allowedPeriod / 4;
 
    // above all, check if the signal comes not too early
    if (currentPeriod >= minAllowedPeriod) {
        // now we store this period as a reference for the next time,
        // BUT we store only 'normal' periods, and ignore too long periods (i.e. gaps)
        if (!isGapExpected && (maxAllowedPeriod == 0 || currentPeriod <= maxAllowedPeriod)) {
            accumSignalPrevPeriods[signal] = currentPeriod;
        }
        // reset accumulator
        accumSignalPeriods[signal] = 0;
        return true;
    }
    // all premature or extra-long events are ignored - treated as interference
    return false;
}
 
void TriggerCentral::decodeMapCam(efitick_t timestamp, float currentPhase) {
    isDecodingMapCam = engineConfiguration->vvtMode[0] == VVT_MAP_V_TWIN &&
                                Sensor::getOrZero(SensorType::Rpm) < engineConfiguration->cranking.rpm;
    if (isDecodingMapCam) {
        // we are trying to figure out which 360 half of the total 720 degree cycle is which, so we compare those in 360 degree sense.
        auto toothAngle360 = currentPhase;
        while (toothAngle360 >= 360) {
            toothAngle360 -= 360;
        }
 
        if (mapCamPrevToothAngle < engineConfiguration->mapCamDetectionAnglePosition && toothAngle360 > engineConfiguration->mapCamDetectionAnglePosition) {
            // we are somewhere close to 'mapCamDetectionAnglePosition'
 
            // warning: hack hack hack
            float map = engine->outputChannels.instantMAPValue;
 
            // Compute diff against the last time we were here
            float diff = map - mapCamPrevCycleValue;
            mapCamPrevCycleValue = map;
 
            if (diff > 0) {
                mapVvt_map_peak++;
                int revolutionCounter = getTriggerCentral()->triggerState.getCrankSynchronizationCounter();
                mapVvt_MAP_AT_CYCLE_COUNT = revolutionCounter - prevChangeAtCycle;
                prevChangeAtCycle = revolutionCounter;
 
                hwHandleVvtCamSignal(TriggerValue::RISE, timestamp, /*index*/0);
                hwHandleVvtCamSignal(TriggerValue::FALL, timestamp, /*index*/0);
#if EFI_UNIT_TEST
                // hack? feature? existing unit test relies on VVT phase available right away
                // but current implementation which is based on periodicFastCallback would only make result available on NEXT tooth
                getLimpManager()->onFastCallback();
#endif // EFI_UNIT_TEST
            }
 
            mapVvt_MAP_AT_SPECIAL_POINT = map;
            mapVvt_MAP_AT_DIFF = diff;
        }
 
        mapCamPrevToothAngle = toothAngle360;
    }
}
 
bool TriggerCentral::isToothExpectedNow(efitick_t timestamp) {
    // Check that the expected next phase (from the last tooth) is close to the actual current phase:
    // basically, check that the tooth width is correct
    auto estimatedCurrentPhase = getCurrentEnginePhase(timestamp);
    auto lastToothPhase = m_lastToothPhaseFromSyncPoint;
 
    if (expectedNextPhase && estimatedCurrentPhase) {
        float angleError = expectedNextPhase.Value - estimatedCurrentPhase.Value;
 
        // Wrap around correctly at the end of the cycle
        float cycle = getEngineState()->engineCycle;
        if (angleError < -cycle / 2) {
            angleError += cycle;
        }
 
        triggerToothAngleError = angleError;
 
        // Only perform checks if engine is spinning quickly
        // All kinds of garbage happens while cranking
        if (Sensor::getOrZero(SensorType::Rpm) > 1000) {
            // Now compute how close we are to the last tooth decoded
            float angleSinceLastTooth = estimatedCurrentPhase.Value - lastToothPhase;
            if (angleSinceLastTooth < 0.5f) {
                // This tooth came impossibly early, ignore it
                // This rejects things like doubled edges, for example:
                //             |-| |----------------
                //             | | |
                // ____________| |_|
                //             1   2
                //     #1 will be decoded
                //     #2 will be ignored
                // We're not sure which edge was the "real" one, but they were close enough
                // together that it doesn't really matter.
                warning(ObdCode::CUSTOM_PRIMARY_DOUBLED_EDGE, "doubled trigger edge after %.2f deg at #%d", angleSinceLastTooth, triggerState.currentCycle.current_index);
 
                return false;
            }
 
            // Absolute error from last tooth
            float absError = absF(angleError);
            float isRpmEnough = Sensor::getOrZero(SensorType::Rpm) > 1000;
            // TODO: configurable threshold
            if (isRpmEnough && absError > 10 && absError < 180) {
                // This tooth came at a very unexpected time, ignore it
                warning(ObdCode::CUSTOM_PRIMARY_BAD_TOOTH_TIMING, "tooth #%d error of %.1f", triggerState.currentCycle.current_index, angleError);
 
                // TODO: this causes issues with some real engine logs, should it?
                // return false;
            }
        }
    } else {
        triggerToothAngleError = 0;
    }
 
    // We aren't ready to reject unexpected teeth, so accept this tooth
    return true;
}
 
BOARD_WEAK bool boardAllowTriggerActions() { return true; }
 
angle_t TriggerCentral::findNextTriggerToothAngle(int p_currentToothIndex) {
  int currentToothIndex = p_currentToothIndex;
        // TODO: is this logic to compute next trigger tooth angle correct?
        angle_t nextPhase = 0;
 
        int loopAllowance = 2 * engineCycleEventCount + 1000;
        do {
            // I don't love this.
            currentToothIndex = (currentToothIndex + 1) % engineCycleEventCount;
            nextPhase = getTriggerCentral()->triggerFormDetails.eventAngles[currentToothIndex] - tdcPosition();
            wrapAngle(nextPhase, "nextEnginePhase", ObdCode::CUSTOM_ERR_6555);
        } while (nextPhase == currentEngineDecodedPhase && --loopAllowance > 0);
        if (nextPhase != 0 && loopAllowance == 0) {
            firmwareError(ObdCode::CUSTOM_ERR_TRIGGER_ZERO, "handleShaftSignal unexpected loop end %d %d %f", p_currentToothIndex, engineCycleEventCount, nextPhase);
        }
        return nextPhase;
}
 
/**
 * This method is NOT invoked for VR falls.
 */
void TriggerCentral::handleShaftSignal(trigger_event_e signal, efitick_t timestamp) {
    if (triggerShape.shapeDefinitionError) {
        // trigger is broken, we cannot do anything here
        warning(ObdCode::CUSTOM_ERR_UNEXPECTED_SHAFT_EVENT, "Shaft event while trigger is mis-configured");
        // magic value to indicate a problem
        hwEventCounters[0] = 155;
        return;
    }
 
    // This code gathers some statistics on signals and compares accumulated periods to filter interference
    if (engineConfiguration->useNoiselessTriggerDecoder) {
        if (!noiseFilter.noiseFilter(timestamp, &triggerState, signal)) {
            return;
        }
        if (!isUsefulSignal(signal, triggerShape)) {
            return;
        }
    }
 
    if (!isToothExpectedNow(timestamp)) {
        triggerIgnoredToothCount++;
        return;
    }
 
    isSpinningJustForWatchdog = true;
 
#if EFI_HD_ACR
    bool firstEventInAWhile = m_lastEventTimer.hasElapsedSec(1);
    if (firstEventInAWhile) {
        // let's open that valve on first sign of movement
        engine->module<HarleyAcr>()->updateAcr();
    }
#endif // EFI_HD_ACR
 
  if (boardAllowTriggerActions()) {
      m_lastEventTimer.reset(timestamp);
  }
 
    int eventIndex = (int) signal;
    efiAssertVoid(ObdCode::CUSTOM_TRIGGER_EVENT_TYPE, eventIndex >= 0 && eventIndex < HW_EVENT_TYPES, "signal type");
    hwEventCounters[eventIndex]++;
 
    // Decode the trigger!
    auto decodeResult = triggerState.decodeTriggerEvent(
            "trigger",
            triggerShape,
            engine,
            primaryTriggerConfiguration,
            signal, timestamp);
 
    // Don't propagate state if we don't know where we are
    if (decodeResult) {
        ScopePerf perf(PE::ShaftPositionListeners);
 
        /**
         * If we only have a crank position sensor with four stroke, here we are extending crank revolutions with a 360 degree
         * cycle into a four stroke, 720 degrees cycle.
         */
        int crankDivider = getCrankDivider(triggerShape.getWheelOperationMode());
        int crankInternalIndex = triggerState.getCrankSynchronizationCounter() % crankDivider;
        int triggerIndexForListeners = decodeResult.Value.CurrentIndex + (crankInternalIndex * triggerShape.getSize());
 
        reportEventToWaveChart(signal, triggerIndexForListeners, triggerShape.useOnlyRisingEdges);
 
        // Look up this tooth's angle from the sync point. If this tooth is the sync point, we'll get 0 here.
        auto currentPhaseFromSyncPoint = getTriggerCentral()->triggerFormDetails.eventAngles[triggerIndexForListeners];
 
        // Adjust so currentPhase is in engine-space angle, not trigger-space angle
        currentEngineDecodedPhase = wrapAngleMethod(currentPhaseFromSyncPoint - tdcPosition(), "currentEnginePhase", ObdCode::CUSTOM_ERR_6555);
 
        // Record precise time and phase of the engine. This is used for VVT decode, and to check that the
        // trigger pattern selected matches reality (ie, we check the next tooth is where we think it should be)
        {
            // under lock to avoid mismatched tooth phase and time
            chibios_rt::CriticalSectionLocker csl;
 
            m_lastToothTimer.reset(timestamp);
            m_lastToothPhaseFromSyncPoint = currentPhaseFromSyncPoint;
        }
 
#if TRIGGER_EXTREME_LOGGING
    efiPrintf("trigger %d %d %d", triggerIndexForListeners, getRevolutionCounter(), time2print(getTimeNowUs()));
#endif /* TRIGGER_EXTREME_LOGGING */
 
        // Update engine RPM
        rpmShaftPositionCallback(signal, triggerIndexForListeners, timestamp);
 
        // Schedule the TDC mark
        tdcMarkCallback(triggerIndexForListeners, timestamp);
 
#if !EFI_UNIT_TEST
#if EFI_MAP_AVERAGING
        mapAveragingTriggerCallback(triggerIndexForListeners, timestamp);
#endif /* EFI_MAP_AVERAGING */
#endif /* EFI_UNIT_TEST */
 
#if EFI_LOGIC_ANALYZER
        waTriggerEventListener(signal, triggerIndexForListeners, timestamp);
#endif
 
        angle_t nextPhase = findNextTriggerToothAngle(triggerIndexForListeners);
 
        float expectNextPhase = nextPhase + tdcPosition();
        wrapAngle(expectNextPhase, "nextEnginePhase", ObdCode::CUSTOM_ERR_6555);
        expectedNextPhase = expectNextPhase;
 
#if EFI_CDM_INTEGRATION
        if (trgEventIndex == 0 && isBrainPinValid(engineConfiguration->cdmInputPin)) {
            int cdmKnockValue = getCurrentCdmValue(getTriggerCentral()->triggerState.getCrankSynchronizationCounter());
            engine->knockLogic(cdmKnockValue);
        }
#endif /* EFI_CDM_INTEGRATION */
 
        if (engine->rpmCalculator.getCachedRpm() > 0 && triggerIndexForListeners == 0) {
            engine->tpsAccelEnrichment.onEngineCycleTps();
        }
 
        // Handle ignition and injection
        mainTriggerCallback(triggerIndexForListeners, timestamp, currentEngineDecodedPhase, nextPhase);
 
        // Decode the MAP based "cam" sensor
        decodeMapCam(timestamp, currentEngineDecodedPhase);
    } else {
        // We don't have sync, but report to the wave chart anyway as index 0.
        reportEventToWaveChart(signal, 0, triggerShape.useOnlyRisingEdges);
 
        expectedNextPhase = unexpected;
    }
}
 
static void triggerShapeInfo() {
#if EFI_PROD_CODE || EFI_SIMULATOR
    TriggerWaveform *shape = &getTriggerCentral()->triggerShape;
    TriggerFormDetails *triggerFormDetails = &getTriggerCentral()->triggerFormDetails;
    efiPrintf("syncEdge=%s", getSyncEdge(TRIGGER_WAVEFORM(syncEdge)));
    efiPrintf("gap from %.2f to %.2f", TRIGGER_WAVEFORM(synchronizationRatioFrom[0]), TRIGGER_WAVEFORM(synchronizationRatioTo[0]));
 
    for (size_t i = 0; i < shape->getSize(); i++) {
        efiPrintf("event %d %.2f", i, triggerFormDetails->eventAngles[i]);
    }
#endif
}
 
#if EFI_PROD_CODE
extern PwmConfig triggerEmulatorSignals[NUM_EMULATOR_CHANNELS];
#endif /* #if EFI_PROD_CODE */
 
void triggerInfo(void) {
#if EFI_PROD_CODE || EFI_SIMULATOR
 
    TriggerCentral *tc = getTriggerCentral();
    TriggerWaveform *ts = &tc->triggerShape;
 
 
#if (HAL_TRIGGER_USE_PAL == TRUE) && (PAL_USE_CALLBACKS == TRUE)
        efiPrintf("trigger PAL mode %d", tc->hwTriggerInputEnabled);
#else
 
#endif /* HAL_TRIGGER_USE_PAL */
 
    efiPrintf("Template %s (%d) trigger %s (%d) syncEdge=%s tdcOffset=%.2f",
            getEngine_type_e(engineConfiguration->engineType), engineConfiguration->engineType,
            getTrigger_type_e(engineConfiguration->trigger.type), engineConfiguration->trigger.type,
            getSyncEdge(TRIGGER_WAVEFORM(syncEdge)), TRIGGER_WAVEFORM(tdcPosition));
 
    if (engineConfiguration->trigger.type == trigger_type_e::TT_TOOTHED_WHEEL) {
        efiPrintf("total %d/skipped %d", engineConfiguration->trigger.customTotalToothCount,
                engineConfiguration->trigger.customSkippedToothCount);
    }
 
 
    efiPrintf("trigger#1 event counters up=%d/down=%d", tc->getHwEventCounter(0),
            tc->getHwEventCounter(1));
 
    if (ts->needSecondTriggerInput) {
        efiPrintf("trigger#2 event counters up=%d/down=%d", tc->getHwEventCounter(2),
                tc->getHwEventCounter(3));
    }
    efiPrintf("expected cycle events %d/%d",
            TRIGGER_WAVEFORM(getExpectedEventCount(TriggerWheel::T_PRIMARY)),
            TRIGGER_WAVEFORM(getExpectedEventCount(TriggerWheel::T_SECONDARY)));
 
    efiPrintf("trigger type=%d/need2ndChannel=%s", engineConfiguration->trigger.type,
            boolToString(TRIGGER_WAVEFORM(needSecondTriggerInput)));
 
 
    efiPrintf("synchronizationNeeded=%s/isError=%s/total errors=%d ord_err=%d/total revolutions=%d/self=%s",
            boolToString(ts->isSynchronizationNeeded),
            boolToString(tc->isTriggerDecoderError()),
            tc->triggerState.totalTriggerErrorCounter,
            tc->triggerState.orderingErrorCounter,
            tc->triggerState.getCrankSynchronizationCounter(),
            boolToString(tc->directSelfStimulation));
 
    if (TRIGGER_WAVEFORM(isSynchronizationNeeded)) {
        efiPrintf("gap from %.2f to %.2f", TRIGGER_WAVEFORM(synchronizationRatioFrom[0]), TRIGGER_WAVEFORM(synchronizationRatioTo[0]));
    }
 
#endif /* EFI_PROD_CODE || EFI_SIMULATOR */
 
#if EFI_PROD_CODE
 
    efiPrintf("primary trigger input: %s", hwPortname(engineConfiguration->triggerInputPins[0]));
    efiPrintf("primary trigger simulator: %s %s freq=%d",
            hwPortname(engineConfiguration->triggerSimulatorPins[0]),
            getPin_output_mode_e(engineConfiguration->triggerSimulatorPinModes[0]),
            engineConfiguration->triggerSimulatorRpm);
 
    if (ts->needSecondTriggerInput) {
        efiPrintf("secondary trigger input: %s", hwPortname(engineConfiguration->triggerInputPins[1]));
#if EFI_EMULATE_POSITION_SENSORS
        efiPrintf("secondary trigger simulator: %s %s phase=%d",
                hwPortname(engineConfiguration->triggerSimulatorPins[1]),
                getPin_output_mode_e(engineConfiguration->triggerSimulatorPinModes[1]), triggerEmulatorSignals[0].safe.phaseIndex);
#endif /* EFI_EMULATE_POSITION_SENSORS */
    }
 
 
    for (int camInputIndex = 0; camInputIndex<CAM_INPUTS_COUNT;camInputIndex++) {
        if (isBrainPinValid(engineConfiguration->camInputs[camInputIndex])) {
            int camLogicalIndex = camInputIndex % CAMS_PER_BANK;
            efiPrintf("VVT input: %s mode %s", hwPortname(engineConfiguration->camInputs[camInputIndex]),
                    getVvt_mode_e(engineConfiguration->vvtMode[camLogicalIndex]));
            efiPrintf("VVT %d event counters: %d/%d",
                    camInputIndex,
                    tc->vvtEventRiseCounter[camInputIndex], tc->vvtEventFallCounter[camInputIndex]);
        }
    }
 
    efiPrintf("primary logic input: %s", hwPortname(engineConfiguration->logicAnalyzerPins[0]));
    efiPrintf("secondary logic input: %s", hwPortname(engineConfiguration->logicAnalyzerPins[1]));
 
 
    efiPrintf("totalTriggerHandlerMaxTime=%d", triggerMaxDuration);
 
#endif /* EFI_PROD_CODE */
 
#if EFI_ENGINE_SNIFFER
    efiPrintf("engine sniffer current size=%d", waveChart.getSize());
#endif /* EFI_ENGINE_SNIFFER */
 
}
 
static void resetRunningTriggerCounters() {
#if !EFI_UNIT_TEST
    getTriggerCentral()->resetCounters();
    triggerInfo();
#endif
}
 
void onConfigurationChangeTriggerCallback() {
    bool changed = false;
    // todo: how do we static_assert here?
    criticalAssertVoid(efi::size(engineConfiguration->camInputs) == efi::size(engineConfiguration->vvtOffsets), "sizes");
 
    for (size_t camIndex = 0; camIndex < efi::size(engineConfiguration->camInputs); camIndex++) {
        changed |= isConfigurationChanged(camInputs[camIndex]);
        changed |= isConfigurationChanged(vvtOffsets[camIndex]);
    }
 
    for (size_t i = 0; i < efi::size(engineConfiguration->triggerGapOverrideFrom); i++) {
        changed |= isConfigurationChanged(triggerGapOverrideFrom[i]);
        changed |= isConfigurationChanged(triggerGapOverrideTo[i]);
    }
 
    for (size_t i = 0; i < efi::size(engineConfiguration->triggerInputPins); i++) {
        changed |= isConfigurationChanged(triggerInputPins[i]);
        Gpio pin = engineConfiguration->camInputs[i];
        if (engineConfiguration->vvtMode[0] == VVT_MAP_V_TWIN && isBrainPinValid(pin)) {
            criticalError("Please no physical sensors in CAM by MAP mode index=%d %s", i, hwPortname(pin));
        }
    }
 
    for (size_t i = 0; i < efi::size(engineConfiguration->vvtMode); i++) {
        changed |= isConfigurationChanged(vvtMode[i]);
    }
 
    changed |= isConfigurationChanged(trigger.type);
    changed |= isConfigurationChanged(skippedWheelOnCam);
    changed |= isConfigurationChanged(twoStroke);
    changed |= isConfigurationChanged(globalTriggerAngleOffset);
    changed |= isConfigurationChanged(trigger.customTotalToothCount);
    changed |= isConfigurationChanged(trigger.customSkippedToothCount);
    changed |= isConfigurationChanged(overrideTriggerGaps);
    changed |= isConfigurationChanged(gapTrackingLengthOverride);
    changed |= isConfigurationChanged(overrideVvtTriggerGaps);
    changed |= isConfigurationChanged(gapVvtTrackingLengthOverride);
 
    if (changed) {
    #if EFI_ENGINE_CONTROL
        engine->updateTriggerWaveform();
        getTriggerCentral()->noiseFilter.resetAccumSignalData();
    #endif
    }
#if EFI_DEFAILED_LOGGING
    efiPrintf("isTriggerConfigChanged=%d", triggerConfigChanged);
#endif /* EFI_DEFAILED_LOGGING */
 
    // we do not want to miss two updates in a row
    getTriggerCentral()->triggerConfigChangedOnLastConfigurationChange = getTriggerCentral()->triggerConfigChangedOnLastConfigurationChange || changed;
}
 
static void initVvtShape(TriggerWaveform& shape, const TriggerConfiguration& p_config, TriggerDecoderBase &initState) {
    shape.initializeTriggerWaveform(FOUR_STROKE_CAM_SENSOR, p_config.TriggerType);
    shape.initializeSyncPoint(initState, p_config);
}
 
void TriggerCentral::validateCamVvtCounters() {
    // micro-optimized 'crankSynchronizationCounter % 256'
    int camVvtValidationIndex = triggerState.getCrankSynchronizationCounter() & 0xFF;
    if (camVvtValidationIndex == 0) {
        vvtCamCounter = 0;
    } else if (camVvtValidationIndex == 0xFE && vvtCamCounter < 60) {
        // magic logic: we expect at least 60 CAM/VVT events for each 256 trigger cycles, otherwise throw a code
        warning(ObdCode::OBD_Camshaft_Position_Sensor_Circuit_Range_Performance, "No Camshaft Position Sensor signals");
    }
}
/**
 * Calculate 'shape.triggerShapeSynchPointIndex' value using 'TriggerDecoderBase *state'
 */
static void calculateTriggerSynchPoint(
        const PrimaryTriggerConfiguration &primaryTriggerConfiguration,
        TriggerWaveform& shape,
        TriggerDecoderBase& initState) {
 
#if EFI_PROD_CODE
    efiAssertVoid(ObdCode::CUSTOM_TRIGGER_STACK, hasLotsOfRemainingStack(), "calc s");
#endif
 
    shape.initializeSyncPoint(initState, primaryTriggerConfiguration);
 
    if (shape.getSize() >= PWM_PHASE_MAX_COUNT) {
        // todo: by the time we are here we had already modified a lot of RAM out of bounds!
        firmwareError(ObdCode::CUSTOM_ERR_TRIGGER_WAVEFORM_TOO_LONG, "Trigger length above maximum: %d", shape.getSize());
        shape.setShapeDefinitionError(true);
        return;
    }
 
    if (shape.getSize() == 0) {
        firmwareError(ObdCode::CUSTOM_ERR_TRIGGER_ZERO, "triggerShape size is zero");
    }
}
 
TriggerDecoderBase initState("init");
 
void TriggerCentral::updateWaveform() {
    // Re-read config in case it's changed
    primaryTriggerConfiguration.update();
    for (int camIndex = 0;camIndex < CAMS_PER_BANK;camIndex++) {
        vvtTriggerConfiguration[camIndex].update();
    }
 
    triggerShape.initializeTriggerWaveform(lookupOperationMode(), primaryTriggerConfiguration.TriggerType);
 
    /**
     * this is only useful while troubleshooting a new trigger shape in the field
     * in very VERY rare circumstances
     */
    if (engineConfiguration->overrideTriggerGaps) {
        int gapIndex = 0;
 
        engine->triggerCentral.triggerShape.gapTrackingLength = engineConfiguration->gapTrackingLengthOverride;
 
        // copy however many the user wants
        for (; gapIndex < engineConfiguration->gapTrackingLengthOverride; gapIndex++) {
            float gapOverrideFrom = engineConfiguration->triggerGapOverrideFrom[gapIndex];
            float gapOverrideTo = engineConfiguration->triggerGapOverrideTo[gapIndex];
            TRIGGER_WAVEFORM(setTriggerSynchronizationGap3(/*gapIndex*/gapIndex, gapOverrideFrom, gapOverrideTo));
        }
 
        // fill the remainder with the default gaps
        for (; gapIndex < GAP_TRACKING_LENGTH; gapIndex++) {
            triggerShape.synchronizationRatioFrom[gapIndex] = NAN;
            triggerShape.synchronizationRatioTo[gapIndex] = NAN;
        }
    }
 
    if (!triggerShape.shapeDefinitionError) {
        int length = triggerShape.getLength();
        engineCycleEventCount = length;
 
        efiAssertVoid(ObdCode::CUSTOM_SHAPE_LEN_ZERO, length > 0, "shapeLength=0");
 
        triggerErrorDetection.clear();
 
        /**
         * 'initState' instance of TriggerDecoderBase is used only to initialize 'this' TriggerWaveform instance
         * #192 BUG real hardware trigger events could be coming even while we are initializing trigger
         */
        calculateTriggerSynchPoint(primaryTriggerConfiguration,
                triggerShape,
                initState);
    }
 
    if (engineConfiguration->overrideVvtTriggerGaps) {
        int gapIndex = 0;
 
        TriggerWaveform *shape = &vvtShape[0];
 
        for (; gapIndex < engineConfiguration->gapVvtTrackingLengthOverride; gapIndex++) {
            float gapOverrideFrom = engineConfiguration->triggerVVTGapOverrideFrom[gapIndex];
            float gapOverrideTo = engineConfiguration->triggerVVTGapOverrideTo[gapIndex];
            shape->synchronizationRatioFrom[gapIndex] = gapOverrideFrom;
            shape->synchronizationRatioTo[gapIndex] = gapOverrideTo;
        }
        // fill the remainder with the default gaps
        for (; gapIndex < VVT_TRACKING_LENGTH; gapIndex++) {
            shape->synchronizationRatioFrom[gapIndex] = NAN;
            shape->synchronizationRatioTo[gapIndex] = NAN;
        }
    }
 
    for (int camIndex = 0; camIndex < CAMS_PER_BANK; camIndex++) {
        // todo: should 'vvtWithRealDecoder' be used here?
        if (engineConfiguration->vvtMode[camIndex] != VVT_INACTIVE) {
            initVvtShape(
                vvtShape[camIndex],
                vvtTriggerConfiguration[camIndex],
                initState
            );
        }
    }
 
    // This is not the right place for this, but further refactoring has to happen before it can get moved.
    triggerState.setNeedsDisambiguation(engine->triggerCentral.triggerShape.needsDisambiguation());
 
}
 
/**
 * @returns true if configuration just changed, and if that change has affected trigger
 */
bool TriggerCentral::checkIfTriggerConfigChanged() {
    // we want to make sure that configuration has changed AND that change has changed trigger specifically
    bool result = triggerVersion.isOld(engine->getGlobalConfigurationVersion()) && triggerConfigChangedOnLastConfigurationChange;
    triggerConfigChangedOnLastConfigurationChange = false; // whoever has called the method is supposed to react to changes
    return result;
}
 
#if EFI_UNIT_TEST
bool TriggerCentral::isTriggerConfigChanged() {
    return triggerConfigChangedOnLastConfigurationChange;
}
#endif // EFI_UNIT_TEST
 
void validateTriggerInputs() {
    if (!isBrainPinValid(engineConfiguration->triggerInputPins[0]) && isBrainPinValid(engineConfiguration->triggerInputPins[1])) {
        criticalError("First trigger channel not configured while second one is.");
    }
 
    if (!isBrainPinValid(engineConfiguration->camInputs[0]) && isBrainPinValid(engineConfiguration->camInputs[2])) {
        criticalError("First bank cam input is required if second bank specified");
    }
}
 
void initTriggerCentral() {
 
#if EFI_ENGINE_SNIFFER
    initWaveChart(&waveChart);
#endif /* EFI_ENGINE_SNIFFER */
 
#if EFI_PROD_CODE || EFI_SIMULATOR
    addConsoleAction(CMD_TRIGGERINFO, triggerInfo);
    addConsoleAction("trigger_shape_info", triggerShapeInfo);
    addConsoleAction("reset_trigger", resetRunningTriggerCounters);
#endif // EFI_PROD_CODE || EFI_SIMULATOR
 
}
 
/**
 * @return TRUE is something is wrong with trigger decoding
 */
bool TriggerCentral::isTriggerDecoderError() {
    return triggerErrorDetection.sum(6) > 4;
}
 
#endif // EFI_SHAFT_POSITION_INPUT