diff --git a/firmware/controllers/trigger/rpm_calculator.cpp b/firmware/controllers/trigger/rpm_calculator.cpp
index 2e2168f367..3a472b14a9 100644
--- a/firmware/controllers/trigger/rpm_calculator.cpp
+++ b/firmware/controllers/trigger/rpm_calculator.cpp
@@ -62,6 +62,7 @@ uint32_t RpmCalculator::getRevolutionCounterSinceStart(void) {
 
 /**
  * @return -1 in case of isNoisySignal(), current RPM otherwise
+ * See NOISY_RPM
  */
 // todo: migrate to float return result or add a float version? this would have with calculations
 int RpmCalculator::getRpm(DECLARE_ENGINE_PARAMETER_SIGNATURE) const {
diff --git a/firmware/controllers/trigger/trigger_central.cpp b/firmware/controllers/trigger/trigger_central.cpp
index 25a270aa3a..c620faeeb0 100644
--- a/firmware/controllers/trigger/trigger_central.cpp
+++ b/firmware/controllers/trigger/trigger_central.cpp
@@ -556,7 +556,7 @@ void triggerInfo(void) {
 #endif /* EFI_PROD_CODE || EFI_SIMULATOR */
 
 #if EFI_PROD_CODE
-	if (engineConfiguration->camInput != GPIO_UNASSIGNED) {
+	if (HAVE_CAM_INPUT()) {
 		scheduleMsg(logger, "VVT input: %s mode %s", hwPortname(engineConfiguration->camInput),
 				getVvt_mode_e(engineConfiguration->vvtMode));
 		scheduleMsg(logger, "VVT event counters: %d/%d", vvtEventRiseCounter, vvtEventFallCounter);
diff --git a/firmware/controllers/trigger/trigger_central.h b/firmware/controllers/trigger/trigger_central.h
index a2726839d0..63aff6234d 100644
--- a/firmware/controllers/trigger/trigger_central.h
+++ b/firmware/controllers/trigger/trigger_central.h
@@ -15,6 +15,8 @@
 class Engine;
 typedef void (*ShaftPositionListener)(trigger_event_e signal, uint32_t index DECLARE_ENGINE_PARAMETER_SUFFIX);
 
+#define HAVE_CAM_INPUT() engineConfiguration->camInput != GPIO_UNASSIGNED
+
 #define HW_EVENT_TYPES 6
 
 /**
diff --git a/unit_tests/engine_test_helper.h b/unit_tests/engine_test_helper.h
index e7510888ed..bca182ebe2 100644
--- a/unit_tests/engine_test_helper.h
+++ b/unit_tests/engine_test_helper.h
@@ -33,11 +33,11 @@ public:
 	void fireFall(int delayMs);
 
 	/**
-	 * See also #fireRise()
+	 * See also #fireRise() which would also move time forward
 	 */
 	void firePrimaryTriggerRise();
 	/**
-	 * See also #fireFall()
+	 * See also #fireFall() which would also move time forward
 	 */
 	void firePrimaryTriggerFall();
 	void fireTriggerEvents(int count);
diff --git a/unit_tests/tests/test_cam_vtt_input.cpp b/unit_tests/tests/test_cam_vtt_input.cpp
index ffb2175cdd..0ed36f69ed 100644
--- a/unit_tests/tests/test_cam_vtt_input.cpp
+++ b/unit_tests/tests/test_cam_vtt_input.cpp
@@ -8,6 +8,30 @@
 #include "engine_test_helper.h"
 
 TEST(sensors, testCamInput) {
+	// setting some weird engine
+	WITH_ENGINE_TEST_HELPER(FORD_ESCORT_GT);
+
+	// and now changing to ONE trigger on CRANK with CAM/VVT
+
+	setOperationMode(engineConfiguration, FOUR_STROKE_CRANK_SENSOR);
+	eth.setTriggerType(TT_ONE PASS_ENGINE_PARAMETER_SUFFIX);
+	engineConfiguration->useOnlyRisingEdgeForTrigger = true;
+	engineConfiguration->camInput = GPIOA_10;
+
+	ASSERT_EQ( 0,  GET_RPM()) << "testCamInput RPM";
+
+	eth.firePrimaryTriggerRise();
+	eth.firePrimaryTriggerRise();
+	eth.firePrimaryTriggerRise();
+	eth.firePrimaryTriggerRise();
+	// error condition since two events happened too quick
+	ASSERT_EQ(NOISY_RPM,  GET_RPM()) << "testCamInput RPM should be noisy";
 
 
+	eth.fireRise(50);
+	eth.fireRise(50);
+	eth.fireRise(50);
+	eth.fireRise(50);
+	eth.fireRise(50);
+	ASSERT_EQ(1200,  GET_RPM()) << "testCamInput RPM";
 }