tests and tunning for external sync and phase_mult system

src/uClock.cpp

@@ -76,12 +76,12 @@ static inline uint32_t phase_mult(uint32_t val)
 	return (val * PHASE_FACTOR) >> 8;
 }
 
-static inline uint16_t clock_diff(uint16_t old_clock, uint16_t new_clock) 
+static inline uint16_t clock_diff(uint32_t old_clock, uint32_t new_clock) 
 {
 	if (new_clock >= old_clock) {
 		return new_clock - old_clock;
 	} else {
-		return new_clock + (65535 - old_clock);
+		return new_clock + (4294967295 - old_clock);
 	}
 }
 
@@ -207,8 +207,23 @@ void uClockClass::setTempo(float bpm)
 	tempo = bpm;
 }
 
+float inline uClockClass::freqToBpm(uint32_t freq)
+{
+	float usecs = 1/((float)freq/1000000.0);
+	return (float)((float)(usecs/24.0) * 60.0);
+}
+
 float uClockClass::getTempo() 
 {
+	if (mode == EXTERNAL_CLOCK) {
+		uint32_t acc = 0;
+		for (uint8_t i=0; i < EXT_INTERVAL_BUFFER_SIZE; i++) {
+			acc += ext_interval_buffer[i];
+		}
+		if (acc != 0) {
+			return freqToBpm(acc / EXT_INTERVAL_BUFFER_SIZE);
+		}
+	}
 	return tempo;
 }
 
@@ -240,6 +255,10 @@ void uClockClass::resetCounters()
 	div32th_counter = 0;
 	div16th_counter = 0;
 	mod6_counter = 0;	
+	indiv32th_counter = 0;
+	indiv16th_counter = 0;
+	inmod6_counter = 0;
+	ext_interval_idx = 0;
 }
 
 // TODO: Tap stuff
@@ -256,12 +275,6 @@ void uClockClass::shuffle()
 
 void uClockClass::handleExternalClock() 
 {
-	uint32_t u_timer = micros();
-	last_interval = clock_diff(external_clock, u_timer);
-	external_clock = u_timer;
-
-	// slave tick me!
-	external_tick++;
 
 	switch (state) {
 		case PAUSED:
@@ -272,6 +285,34 @@ void uClockClass::handleExternalClock()
 			break;
 
 		case STARTED:
+
+			uint32_t u_timer = micros();
+			last_interval = clock_diff(external_clock, u_timer);
+			external_clock = u_timer;
+
+			if (inmod6_counter == 0) {
+				indiv16th_counter++;
+				indiv32th_counter++;
+			}
+
+			if (inmod6_counter == 3) {
+				indiv32th_counter++;
+			}
+
+			// slave tick me!
+			external_tick++;
+			inmod6_counter++;
+
+			if (inmod6_counter == 6) {
+				inmod6_counter = 0;
+			}
+
+			// accumulate interval incomming ticks data for getTempo() smooth reads on slave mode
+			if(++ext_interval_idx >= EXT_INTERVAL_BUFFER_SIZE) {
+				ext_interval_idx = 0;
+			}
+			ext_interval_buffer[ext_interval_idx] = last_interval;
+
 			if (external_tick == 1) {
 				interval = last_interval;
 			} else {
@@ -283,10 +324,15 @@ void uClockClass::handleExternalClock()
 
 void uClockClass::handleTimerInt()  
 {
-	//if (counter == 0) {
-
 	counter = interval;
 
+	if ((internal_tick < external_tick) || (internal_tick > (external_tick + 1))) {
+		internal_tick = external_tick;
+		div32th_counter = indiv32th_counter;
+		div16th_counter = indiv16th_counter;
+		mod6_counter = inmod6_counter;
+	}
+
 	if (onClock96PPQNCallback) {
 		onClock96PPQNCallback(&internal_tick);
 	}
@@ -313,12 +359,14 @@ void uClockClass::handleTimerInt()
 	internal_tick++;
 	mod6_counter++;
 
+	if (mod6_counter == 6) {
+		mod6_counter = 0;
+	}
+
 	if (mode == EXTERNAL_CLOCK) {
 		uint32_t u_timer = micros();
 		sync_interval = clock_diff(external_clock, u_timer);
-			if ((internal_tick < external_tick) || (internal_tick > (external_tick + 1))) {
-				internal_tick = external_tick;
-			}
+
 		if (internal_tick <= external_tick) {
 			counter -= phase_mult(sync_interval);
 		} else {
@@ -327,24 +375,16 @@ void uClockClass::handleTimerInt()
 			}
 		}
 
-			// update internal clock base counter
-			float diff = 1/((float)counter/1000000.0);
-			float bpm = (float)((float)(diff/24.0) * 60.0);
+		// update internal clock timer frequency
+		float bpm = freqToBpm(counter);
 		if (bpm != tempo) {
-				if (bpm > 1 && bpm < 300) {
+			if (bpm >= MIN_BPM && bpm <= MAX_BPM) {
 				tempo = bpm;
 				setTimerTempo(tempo);
 			}
 		}
 	}
 	
-		if (mod6_counter == 6) {
-			mod6_counter = 0;
-		}
-
-	//} else {
-	//	counter--;
-	//}
 }
 
 // elapsed time support

src/uClock.h

@@ -39,6 +39,8 @@ namespace umodular { namespace clock {
 
 #define PHASE_FACTOR 16
 
+#define EXT_INTERVAL_BUFFER_SIZE 24
+
 #define SECS_PER_MIN  (60UL)
 #define SECS_PER_HOUR (3600UL)
 #define SECS_PER_DAY  (SECS_PER_HOUR * 24L)
@@ -53,6 +55,7 @@ class uClockClass {
 	private:
 		
 		void setTimerTempo(float bpm);
+		float inline freqToBpm(uint32_t freq);
 
 		void (*onClock96PPQNCallback)(uint32_t * tick);
 		void (*onClock32PPQNCallback)(uint32_t * tick);
@@ -60,16 +63,27 @@ class uClockClass {
 		void (*onClockStartCallback)();
 		void (*onClockStopCallback)();
 
-		volatile uint32_t internal_tick;
-		volatile uint32_t external_tick;
+
 		volatile uint32_t interval;
 		volatile uint32_t external_clock;
 		uint32_t tick_us_interval;
 		float tick_hertz_interval;
-		uint32_t div32th_counter;
-		uint32_t div16th_counter;
-		uint8_t mod6_counter;
-		uint16_t counter;
+
+		volatile uint32_t internal_tick;
+		volatile uint32_t external_tick;
+
+		// tick external and internal control
+		volatile uint32_t indiv32th_counter;
+		volatile uint32_t indiv16th_counter;
+		volatile uint8_t inmod6_counter;
+
+  		volatile uint32_t div96th_counter;
+		volatile uint32_t div32th_counter;
+		volatile uint32_t div16th_counter;
+		volatile uint8_t mod6_counter;
+
+
+		uint32_t counter;
 		uint16_t pll_x;
 
 		uint32_t last_tick;
@@ -80,6 +94,9 @@ class uClockClass {
 		uint16_t last_interval;
 		uint16_t sync_interval;
 
+		uint16_t ext_interval_buffer[EXT_INTERVAL_BUFFER_SIZE];
+		uint16_t ext_interval_idx;
+
 	public:
 
 		enum {