firmware/CHANGELOG.md

@@ -43,7 +43,6 @@ or
  - TunerStudio UI improvements (#436, etc)
  - Dropdown selector for popular gearbox ratios (#358, thank you @alrijleh and @nmschulte!)
  - Add two more aux linear sensors #476
- - Support wasted spark on odd cylinder count 4-stroke engines. Improves startup and allows running without a cam sensor!
 
 ### Fixed
  - Improve performance with Lua CAN reception of a high volume of frames

firmware/controllers/algo/engine_state.h

@@ -24,8 +24,6 @@ public:
 	 */
 	angle_t engineCycle;
 
-	bool useOddFireWastedSpark = false;
-
 	/**
 	 * this is based on sensorChartMode and sensorSnifferRpmThreshold settings
 	 */

firmware/controllers/engine_cycle/spark_logic.cpp

@@ -104,14 +104,6 @@ static void prepareCylinderIgnitionSchedule(angle_t dwellAngleDuration, floatms_
 	event->sparkAngle = sparkAngle;
 
 	auto ignitionMode = getCurrentIgnitionMode();
-
-	// On an odd cylinder (or odd fire) wasted spark engine, map outputs as if in sequential.
-	// During actual scheduling, the events just get scheduled every 360 deg instead
-	// of every 720 deg.
-	if (ignitionMode == IM_WASTED_SPARK && engine->engineState.useOddFireWastedSpark) {
-		ignitionMode = IM_INDIVIDUAL_COILS;
-	}
-
 	engine->outputChannels.currentIgnitionMode = static_cast<uint8_t>(ignitionMode);
 
 	const int index = getIgnitionPinForIndex(event->cylinderIndex, ignitionMode);
@@ -317,9 +309,20 @@ void turnSparkPinHigh(IgnitionEvent *event) {
 }
 
 static void scheduleSparkEvent(bool limitedSpark, IgnitionEvent *event,
-		int rpm, float dwellMs, float dwellAngle, float sparkAngle, efitick_t edgeTimestamp, float currentPhase, float nextPhase) {
+		int rpm, efitick_t edgeTimestamp, float currentPhase, float nextPhase) {
 
-	float angleOffset = dwellAngle - currentPhase;
+	angle_t sparkAngle = event->sparkAngle;
+	const floatms_t dwellMs = engine->ignitionState.sparkDwell;
+	if (std::isnan(dwellMs) || dwellMs <= 0) {
+		warning(ObdCode::CUSTOM_DWELL, "invalid dwell to handle: %.2f at %d", dwellMs, rpm);
+		return;
+	}
+	if (std::isnan(sparkAngle)) {
+		warning(ObdCode::CUSTOM_ADVANCE_SPARK, "NaN advance");
+		return;
+	}
+
+	float angleOffset = event->dwellAngle - currentPhase;
 	if (angleOffset < 0) {
 		angleOffset += engine->engineState.engineCycle;
 	}
@@ -454,12 +457,6 @@ void onTriggerEventSparkLogic(int rpm, efitick_t edgeTimestamp, float currentPha
 	engine->outputChannels.sparkCutReason = (int8_t)limitedSparkState.reason;
 	bool limitedSpark = !limitedSparkState.value;
 
-	const floatms_t dwellMs = engine->ignitionState.sparkDwell;
-	if (std::isnan(dwellMs) || dwellMs <= 0) {
-		warning(ObdCode::CUSTOM_DWELL, "invalid dwell to handle: %.2f at %d", dwellMs, rpm);
-		return;
-	}
-
 	if (!engine->ignitionEvents.isReady) {
 		prepareIgnitionSchedule();
 	}
@@ -470,48 +467,13 @@ void onTriggerEventSparkLogic(int rpm, efitick_t edgeTimestamp, float currentPha
 	 * See initializeIgnitionActions()
 	 */
 
-	// Only apply odd cylinder count wasted logic if:
-	// - odd cyl count
-	// - current mode is wasted spark
-	// - four stroke
-	bool enableOddCylinderWastedSpark =
-		engine->engineState.useOddFireWastedSpark
-		&& getCurrentIgnitionMode() == IM_WASTED_SPARK;
 
+//	scheduleSimpleMsg(&logger, "eventId spark ", eventIndex);
 	if (engine->ignitionEvents.isReady) {
 		for (size_t i = 0; i < engineConfiguration->cylindersCount; i++) {
 			IgnitionEvent *event = &engine->ignitionEvents.elements[i];
 
-			angle_t dwellAngle = event->dwellAngle;
-
-			angle_t sparkAngle = event->sparkAngle;
-			if (std::isnan(sparkAngle)) {
-				warning(ObdCode::CUSTOM_ADVANCE_SPARK, "NaN advance");
-				continue;
-			}
-
-			bool isOddCylWastedEvent = false;
-			if (enableOddCylinderWastedSpark) {
-				auto dwellAngleWastedEvent = dwellAngle + 360;
-				if (dwellAngleWastedEvent > 720) {
-					dwellAngleWastedEvent -= 720;
-				}
-
-				// Check whether this event hits 360 degrees out from now (ie, wasted spark),
-				// and if so, twiddle the dwell and spark angles so it happens now instead
-				isOddCylWastedEvent = isPhaseInRange(dwellAngleWastedEvent, currentPhase, nextPhase);
-
-				if (isOddCylWastedEvent) {
-					dwellAngle = dwellAngleWastedEvent;
-
-					sparkAngle += 360;
-					if (sparkAngle > 720) {
-						sparkAngle -= 720;
-					}
-				}
-			}
-
-			if (!isOddCylWastedEvent && !isPhaseInRange(dwellAngle, currentPhase, nextPhase)) {
+			if (!isPhaseInRange(event->dwellAngle, currentPhase, nextPhase)) {
 				continue;
 			}
 
@@ -536,7 +498,7 @@ void onTriggerEventSparkLogic(int rpm, efitick_t edgeTimestamp, float currentPha
             engine->ALSsoftSparkLimiter.setTargetSkipRatio(ALSSkipRatio);
 #endif // EFI_ANTILAG_SYSTEM
 
-			scheduleSparkEvent(limitedSpark, event, rpm, dwellMs, dwellAngle, sparkAngle, edgeTimestamp, currentPhase, nextPhase);
+			scheduleSparkEvent(limitedSpark, event, rpm, edgeTimestamp, currentPhase, nextPhase);
 		}
 	}
 }

firmware/controllers/limp_manager.cpp

@@ -19,6 +19,12 @@ static bool noFiringUntilVvtSync(vvt_mode_e vvtMode) {
 		return true;
 	}
 
+	// Odd cylinder count engines don't work properly with wasted spark, so wait for full sync (so that sequential works)
+	// See https://github.com/rusefi/rusefi/issues/4195 for the issue to properly support this case
+	if (engineConfiguration->cylindersCount > 1 && engineConfiguration->cylindersCount % 2 == 1) {
+		return true;
+	}
+
 	// Symmetrical crank modes require cam sync before firing
 	// non-symmetrical cranks can use faster spin-up mode (firing in wasted/batch before VVT sync)
 	// Examples include Nissan MR/VQ, Miata NB, etc

firmware/controllers/math/engine_math.cpp

@@ -386,7 +386,8 @@ ignition_mode_e getCurrentIgnitionMode() {
 	ignition_mode_e ignitionMode = engineConfiguration->ignitionMode;
 #if EFI_SHAFT_POSITION_INPUT
 	// In spin-up cranking mode we don't have full phase sync info yet, so wasted spark mode is better
-	if (ignitionMode == IM_INDIVIDUAL_COILS) {
+	// However, only do this on even cylinder count engines: odd cyl count doesn't fire at all
+	if (ignitionMode == IM_INDIVIDUAL_COILS && (engineConfiguration->cylindersCount % 2 == 0)) {
 		bool missingPhaseInfoForSequential = 
 			!engine->triggerCentral.triggerState.hasSynchronizedPhase();
 
@@ -404,20 +405,7 @@ ignition_mode_e getCurrentIgnitionMode() {
  * This heavy method is only invoked in case of a configuration change or initialization.
  */
 void prepareOutputSignals() {
-	auto operationMode = getEngineRotationState()->getOperationMode();
-	getEngineState()->engineCycle = getEngineCycle(operationMode);
-
-	bool isOddFire = false;
-	for (size_t i = 0; i < engineConfiguration->cylindersCount; i++) {
-		if (engineConfiguration->timing_offset_cylinder[i] != 0) {
-			isOddFire = true;
-			break;
-		}
-	}
-
-	// Use odd fire wasted spark logic if not two stroke, and an odd fire or odd cylinder # engine
-	getEngineState()->useOddFireWastedSpark = operationMode != TWO_STROKE
-								&& (isOddFire | (engineConfiguration->cylindersCount % 2 == 1));
+	getEngineState()->engineCycle = getEngineCycle(getEngineRotationState()->getOperationMode());
 
 #if EFI_UNIT_TEST
 	if (verboseMode) {

unit_tests/tests/ignition_injection/test_ignition_scheduling.cpp

@@ -9,8 +9,6 @@
 #include "spark_logic.h"
 
 using ::testing::_;
-using ::testing::InSequence;
-using ::testing::StrictMock;
 
 TEST(ignition, twoCoils) {
 	EngineTestHelper eth(engine_type_e::FRANKENSO_BMW_M73_F);
@@ -150,55 +148,3 @@ TEST(ignition, CylinderTimingTrim) {
 	EXPECT_NEAR(engine->engineState.timingAdvance[2], unadjusted + 2, EPS4D);
 	EXPECT_NEAR(engine->engineState.timingAdvance[3], unadjusted + 4, EPS4D);
 }
-
-TEST(ignition, oddCylinderWastedSpark) {
-	StrictMock<MockExecutor> mockExec;
-
-	EngineTestHelper eth(engine_type_e::TEST_ENGINE);
-	engine->scheduler.setMockExecutor(&mockExec);
-	engineConfiguration->cylindersCount = 1;
-	engineConfiguration->firingOrder = FO_1;
-	engineConfiguration->ignitionMode = IM_WASTED_SPARK;
-
-	efitick_t nowNt1 = 1000000;
-	efitick_t nowNt2 = 2222222;
-
-
-	engine->rpmCalculator.oneDegreeUs = 100;
-
-	{
-		InSequence is;
-
-		// Should schedule one dwell+fire pair:
-		// Dwell 5 deg from now
-		float nt1deg = USF2NT(engine->rpmCalculator.oneDegreeUs);
-		efitick_t startTime = nowNt1 + nt1deg * 5;
-		EXPECT_CALL(mockExec, schedule(testing::NotNull(), _, startTime, _));
-		// Spark 15 deg from now
-		efitick_t endTime = startTime + nt1deg * 10;
-		EXPECT_CALL(mockExec, schedule(testing::NotNull(), _, endTime, _));
-
-
-		// Should schedule second dwell+fire pair, the out of phase copy
-		// Dwell 5 deg from now
-		startTime = nowNt2 + nt1deg * 5;
-		EXPECT_CALL(mockExec, schedule(testing::NotNull(), _, startTime, _));
-		// Spark 15 deg from now
-		endTime = startTime + nt1deg * 10;
-		EXPECT_CALL(mockExec, schedule(testing::NotNull(), _, endTime, _));
-	}
-
-	engine->ignitionState.sparkDwell = 1;
-
-	// dwell should start at 15 degrees ATDC and firing at 25 deg ATDC
-	engine->ignitionState.dwellAngle = 10;
-	engine->engineState.timingAdvance[0] = -25;
-	engine->engineState.useOddFireWastedSpark = true;
-	engineConfiguration->minimumIgnitionTiming = -25;
-
-	// expect to schedule the on-phase dwell and spark (not the wasted spark copy)
-	onTriggerEventSparkLogic(1200, nowNt1, 10, 30);
-
-	// expect to schedule second events, the out-of-phase dwell and spark (the wasted spark copy)
-	onTriggerEventSparkLogic(1200, nowNt2, 360 + 10, 360 + 30);
-}