From ac7c2290ca39834e87c3162949a1ebd4d1b1a35e Mon Sep 17 00:00:00 2001
From: rusefi <arro239+rusefi@gmail.com>
Date: Sun, 3 Dec 2017 23:58:48 -0500
Subject: [PATCH] #58

---
 firmware/controllers/trigger/rpm_calculator.h |  9 +++-
 .../controllers/trigger/trigger_decoder.h     |  7 +++
 .../controllers/trigger/trigger_structure.cpp | 48 ++++++++++++-------
 3 files changed, 45 insertions(+), 19 deletions(-)

diff --git a/firmware/controllers/trigger/rpm_calculator.h b/firmware/controllers/trigger/rpm_calculator.h
index efdab6cb31..cf9c6d29c2 100644
--- a/firmware/controllers/trigger/rpm_calculator.h
+++ b/firmware/controllers/trigger/rpm_calculator.h
@@ -79,15 +79,22 @@ public:
 	uint32_t getRevolutionCounter(void);
 	void setRpmValue(int value DECLARE_ENGINE_PARAMETER_SUFFIX);
 	uint32_t getRevolutionCounterSinceStart(void);
+	/**
+	 * RPM rate of change between current RPM and RPM measured during previous engine cycle
+	 * see also SC_RPM_ACCEL
+	 */
 	float getRpmAcceleration();
 	/**
 	 * This is public because sometimes we cannot afford to call isRunning() and the value is good enough
 	 * Zero if engine is not running
 	 */
 	volatile int rpmValue;
+	/**
+	 * this is RPM on previous engine cycle.
+	 */
 	int previousRpmValue;
 	/**
-	 * This is a performance optimization: let's pre-calulate this each time RPM changes
+	 * This is a performance optimization: let's pre-calculate this each time RPM changes
 	 * NaN while engine is not spinning
 	 */
 	volatile floatus_t oneDegreeUs;
diff --git a/firmware/controllers/trigger/trigger_decoder.h b/firmware/controllers/trigger/trigger_decoder.h
index ca81ae856d..7868f309ed 100644
--- a/firmware/controllers/trigger/trigger_decoder.h
+++ b/firmware/controllers/trigger/trigger_decoder.h
@@ -118,8 +118,15 @@ private:
  */
 class TriggerStateWithRunningStatistics : public TriggerState {
 public:
+	/**
+	 * timestamp of each trigger wheel tooth
+	 */
 	uint32_t timeOfLastEvent[PWM_PHASE_MAX_COUNT];
+	/**
+	 * instant RPM calculated at this trigger wheel tooth
+	 */
 	float instantRpmValue[PWM_PHASE_MAX_COUNT];
+	float calculateInstantRpm(int *prevIndex, efitime_t nowNt DECLARE_ENGINE_PARAMETER_SUFFIX);
 	virtual void runtimeStatistics(trigger_event_e const signal, efitime_t nowNt DECLARE_ENGINE_PARAMETER_SUFFIX);
 };
 
diff --git a/firmware/controllers/trigger/trigger_structure.cpp b/firmware/controllers/trigger/trigger_structure.cpp
index cda678d8ed..149ee730f2 100644
--- a/firmware/controllers/trigger/trigger_structure.cpp
+++ b/firmware/controllers/trigger/trigger_structure.cpp
@@ -212,32 +212,44 @@ void TriggerState::runtimeStatistics(trigger_event_e const signal, efitime_t now
 	// empty base implementation
 }
 
+float TriggerStateWithRunningStatistics::calculateInstantRpm(int *prevIndex, efitime_t nowNt DECLARE_ENGINE_PARAMETER_SUFFIX) {
+	/**
+	 * Here we calculate RPM based on last 90 degrees
+	 */
+	angle_t currentAngle = TRIGGER_SHAPE(eventAngles[currentCycle.current_index]);
+	// todo: make this '90' depend on cylinder count?
+	angle_t previousAngle = currentAngle - 90;
+	fixAngle(previousAngle, "prevAngle");
+	// todo: prevIndex should be pre-calculated
+	*prevIndex = TRIGGER_SHAPE(triggerIndexByAngle[(int)previousAngle]);
+
+	// now let's get precise angle for that event
+	angle_t prevIndexAngle = TRIGGER_SHAPE(eventAngles[*prevIndex]);
+	uint32_t time = nowNt - timeOfLastEvent[*prevIndex];
+	angle_t angleDiff = currentAngle - prevIndexAngle;
+	// todo: angle diff should be pre-calculated
+	fixAngle(angleDiff, "angleDiff");
+
+	float instantRpm = (60000000.0 / 360 * US_TO_NT_MULTIPLIER) * angleDiff / time;
+	instantRpmValue[currentCycle.current_index] = instantRpm;
+	timeOfLastEvent[currentCycle.current_index] = nowNt;
+
+	return instantRpm;
+}
+
 void TriggerStateWithRunningStatistics::runtimeStatistics(trigger_event_e const signal, efitime_t nowNt DECLARE_ENGINE_PARAMETER_SUFFIX) {
 	if (ENGINE(sensorChartMode) == SC_RPM_ACCEL || ENGINE(sensorChartMode) == SC_DETAILED_RPM) {
-		angle_t currentAngle = TRIGGER_SHAPE(eventAngles[currentCycle.current_index]);
-		// todo: make this '90' depend on cylinder count?
-		angle_t prevAngle = currentAngle - 90;
-		fixAngle(prevAngle, "prevAngle");
-		// todo: prevIndex should be pre-calculated
-		int prevIndex = TRIGGER_SHAPE(triggerIndexByAngle[(int)prevAngle]);
-		// now let's get precise angle for that event
-		prevAngle = TRIGGER_SHAPE(eventAngles[prevIndex]);
-		uint32_t time = nowNt - timeOfLastEvent[prevIndex];
-		angle_t angleDiff = currentAngle - prevAngle;
-		// todo: angle diff should be pre-calculated
-		fixAngle(angleDiff, "angleDiff");
-
-		float r = (60000000.0 / 360 * US_TO_NT_MULTIPLIER) * angleDiff / time;
+		int prevIndex;
+		float instantRpm = calculateInstantRpm(&prevIndex, nowNt PASS_ENGINE_PARAMETER_SUFFIX);
 
 #if EFI_SENSOR_CHART || defined(__DOXYGEN__)
+		angle_t currentAngle = TRIGGER_SHAPE(eventAngles[currentCycle.current_index]);
 		if (boardConfiguration->sensorChartMode == SC_DETAILED_RPM) {
-			scAddData(currentAngle, r);
+			scAddData(currentAngle, instantRpm);
 		} else {
-			scAddData(currentAngle, r / instantRpmValue[prevIndex]);
+			scAddData(currentAngle, instantRpm / instantRpmValue[prevIndex]);
 		}
 #endif /* EFI_SENSOR_CHART */
-		instantRpmValue[currentCycle.current_index] = r;
-		timeOfLastEvent[currentCycle.current_index] = nowNt;
 	}
 }