don't accidentally put it back in a 64 bit num

firmware/controllers/algo/event_registry.h

@@ -70,10 +70,9 @@ public:
 	 */
 	angle_t sparkAngle = NAN;
 	floatms_t sparkDwell = 0;
-	/**
-	 * this timestamp allows us to measure actual dwell time
-	 */
-	uint32_t actualStartOfDwellNt = 0;
+
+	// this timer allows us to measure actual dwell time
+	Timer actualDwellTimer;
 
 	float dwellAngle = 0;
 

firmware/controllers/date_stamp.h

@@ -1,2 +1,2 @@
 #pragma once
-#define VCS_DATE 20240425
+#define VCS_DATE 20240426

firmware/controllers/engine_cycle/spark_logic.cpp

@@ -208,11 +208,12 @@ void fireSparkAndPrepareNextSchedule(IgnitionEvent *event) {
 #if !EFI_UNIT_TEST
 if (engineConfiguration->debugMode == DBG_DWELL_METRIC) {
 #if EFI_TUNER_STUDIO
-	uint32_t actualDwellDurationNt = getTimeNowLowerNt() - event->actualStartOfDwellNt;
+	float actualDwellMs = event->actualDwellTimer.getElapsedSeconds(nowNt) * 1e3;
+
 	/**
 	 * ratio of desired dwell duration to actual dwell duration gives us some idea of how good is input trigger jitter
 	 */
-	float ratio = NT2US(actualDwellDurationNt) / 1000.0 / event->sparkDwell;
+	float ratio = actualDwellMs / event->sparkDwell;
 
 	// todo: smarted solution for index to field mapping
 	switch (event->cylinderIndex) {
@@ -317,10 +318,10 @@ static bool startDwellByTurningSparkPinHigh(IgnitionEvent *event, IgnitionOutput
 }
 
 void turnSparkPinHighStartCharging(IgnitionEvent *event) {
-	event->actualStartOfDwellNt = getTimeNowLowerNt();
-
 	efitick_t nowNt = getTimeNowNt();
 
+	event->actualDwellTimer.reset(nowNt);
+
   bool skippedDwellDueToTriggerNoised = false;
 	for (int i = 0; i< MAX_OUTPUTS_FOR_IGNITION;i++) {
 		IgnitionOutputPin *output = event->outputs[i];

firmware/controllers/trigger/instant_rpm_calculator.cpp

@@ -51,10 +51,15 @@ float InstantRpmCalculator::calculateInstantRpm(
 	TriggerWaveform const & triggerShape, TriggerFormDetails *triggerFormDetails,
 	uint32_t current_index, efitick_t nowNt) {
 
+	// It's OK to truncate from 64b to 32b, ARM with single precision FPU uses an expensive
+	// software function to convert 64b int -> float, while 32b int -> float is very cheap hardware conversion
+	// The difference is guaranteed to be short (it's 90 degrees of engine rotation!), so it won't overflow.
+	uint32_t nowNt32 = nowNt;
+
 	assertIsInBoundsWithResult(current_index, timeOfLastEvent, "calc timeOfLastEvent", 0);
 
 	// Record the time of this event so we can calculate RPM from it later
-	timeOfLastEvent[current_index] = nowNt;
+	timeOfLastEvent[current_index] = nowNt32;
 
 	// Determine where we currently are in the revolution
 	angle_t currentAngle = triggerFormDetails->eventAngles[current_index];
@@ -67,17 +72,14 @@ float InstantRpmCalculator::calculateInstantRpm(
 
 	// now let's get precise angle for that event
 	angle_t prevIndexAngle = triggerFormDetails->eventAngles[prevIndex];
-	efitick_t time90ago = timeOfLastEvent[prevIndex];
+	auto time90ago = timeOfLastEvent[prevIndex];
 
 	// No previous timestamp, instant RPM isn't ready yet
 	if (time90ago == 0) {
 		return prevInstantRpmValue;
 	}
 
-	// It's OK to truncate from 64b to 32b, ARM with single precision FPU uses an expensive
-	// software function to convert 64b int -> float, while 32b int -> float is very cheap hardware conversion
-	// The difference is guaranteed to be short (it's 90 degrees of engine rotation!), so it won't overflow.
-	uint32_t time = nowNt - time90ago;
+	uint32_t time = nowNt32 - time90ago;
 	angle_t angleDiff = currentAngle - prevIndexAngle;
 
 	// Wrap the angle in to the correct range (ie, could be -630 when we want +90)
@@ -113,7 +115,8 @@ void InstantRpmCalculator::setLastEventTimeForInstantRpm(efitick_t nowNt) {
 		return;
 	}
 
-	spinningEvents[spinningEventIndex] = nowNt;
+	uint32_t nowNt32 = nowNt;
+	spinningEvents[spinningEventIndex] = nowNt32;
 
 	// If we are using only rising edges, we never write in to the odd-index slots that
 	// would be used by falling edges

firmware/hw_layer/smart_gpio.cpp

@@ -307,6 +307,7 @@ void initSmartGpio() {
 
 void tle8888startup() {
 #if EFI_PROD_CODE && (BOARD_TLE8888_COUNT > 0)
+  // TODO: use a timer instead
 	static efitick_t tle8888CrankingResetTime = 0;
 
 	if (engineConfiguration->useTLE8888_cranking_hack && engine->rpmCalculator.isCranking()) {

simulator/generated/simulator_tune.msq

@@ -208,7 +208,7 @@
         <constant name="acrPin">"NONE"</constant>
         <constant digits="1" name="driveWheelRevPerKm" units="revs/km">1000.0</constant>
         <constant digits="2" name="canSleepPeriodMs" units="ms">50.0</constant>
-        <constant digits="0" name="byFirmwareVersion" units="index">2.0240425E7</constant>
+        <constant digits="0" name="byFirmwareVersion" units="index">2.0240426E7</constant>
         <constant name="tps1_1AdcChannel">"Disabled"</constant>
         <constant name="vbattAdcChannel">"Disabled"</constant>
         <constant name="fuelLevelSensor">"Disabled"</constant>