added setExtIntervalBuffer(uint8_t buffer_size) for getTempo() average calculus setup. should be called before uClock.init();

src/uClock.cpp

@@ -142,6 +142,9 @@ uClockClass::uClockClass()
 
 void uClockClass::init()
 {
+    if (ext_interval_buffer == nullptr)
+        setExtIntervalBuffer(1);
+
     uclockInitTimer();
     // first interval calculus
     setTempo(tempo);
@@ -244,14 +247,14 @@ float uClockClass::getTempo()
     if (clock_mode == EXTERNAL_CLOCK) {
         uint32_t acc = 0;
         // wait the buffer to get full
-        if (ext_interval_buffer[EXT_INTERVAL_BUFFER_SIZE-1] == 0) {
+        if (ext_interval_buffer[ext_interval_buffer_size-1] == 0) {
             return tempo;
         }
-        for (uint8_t i=0; i < EXT_INTERVAL_BUFFER_SIZE; i++) {
+        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 freqToBpm(acc / ext_interval_buffer_size);
         }
     }
     return tempo;
@@ -291,6 +294,16 @@ void uClockClass::clockMe()
     }
 }
 
+void uClockClass::setExtIntervalBuffer(uint8_t buffer_size)
+{
+    if (ext_interval_buffer != nullptr)
+        return;
+
+    // alloc once and forever policy
+    ext_interval_buffer_size = buffer_size;
+    ext_interval_buffer = (uint32_t*) malloc( sizeof(uint32_t) * ext_interval_buffer_size );
+}
+
 void uClockClass::resetCounters()
 {
     tick = 0;
@@ -317,7 +330,7 @@ void uClockClass::resetCounters()
     mod_sync48_counter = 0;
     sync48_tick = 0;
 
-    for (uint8_t i=0; i < EXT_INTERVAL_BUFFER_SIZE; i++) {
+    for (uint8_t i=0; i < ext_interval_buffer_size; i++) {
         ext_interval_buffer[i] = 0;
     }
 }
@@ -434,7 +447,7 @@ void uClockClass::handleExternalClock()
             ext_clock_tick++;
 
             // accumulate interval incomming ticks data for getTempo() smooth reads on slave clock_mode
-            if(++ext_interval_idx >= EXT_INTERVAL_BUFFER_SIZE) {
+            if(++ext_interval_idx >= ext_interval_buffer_size) {
                 ext_interval_idx = 0;
             }
             ext_interval_buffer[ext_interval_idx] = last_interval;

src/uClock.h

@@ -45,12 +45,6 @@ typedef struct {
     int8_t step[MAX_SHUFFLE_TEMPLATE_SIZE] = {0};
 } SHUFFLE_TEMPLATE;
 
-// for smooth slave tempo calculate display you should raise this value 
-// in between 64 to 128.
-// note: this doesn't impact on sync time, only display time getTempo()
-// if you dont want to use it, set it to 1 for memory save
-#define EXT_INTERVAL_BUFFER_SIZE 128
-
 #define MIN_BPM	1
 #define MAX_BPM	400
 
@@ -160,6 +154,11 @@ class uClockClass {
         void setClockMode(ClockMode tempo_mode);
         ClockMode getClockMode();
         void clockMe();
+        // for smooth slave tempo calculate display you should raise the
+        // buffer_size of ext_interval_buffer in between 64 to 128. 254 max size.
+        // note: this doesn't impact on sync time, only display time getTempo()
+        // if you dont want to use it, it is default set it to 1 for memory save
+        void setExtIntervalBuffer(uint8_t buffer_size);
 
         // shuffle
         void setShuffle(bool active);
@@ -246,7 +245,8 @@ class uClockClass {
         uint32_t start_timer;
         ClockMode clock_mode;
 
-        volatile uint32_t ext_interval_buffer[EXT_INTERVAL_BUFFER_SIZE];
+        volatile uint32_t * ext_interval_buffer = nullptr;
+        uint8_t ext_interval_buffer_size;
         uint16_t ext_interval_idx;
 
         // shuffle implementation
@@ -265,4 +265,3 @@ extern "C" {
 }
 
 #endif /* __U_CLOCK_H__ */
-