Rotation calculation improvements

Brixcer_Box/include/KnobControl.h

@@ -1,13 +1,20 @@
 class KnobControl {
 
+    // Interval of time to count the number of rotations
+    static const int ROTATION_COUNT_INTERVAL_MS = 200;
+
     int knobPinA;
     int knobPinB;
     int buttonPin;
 
     int state;
 
+    int rotationCounter;
+    unsigned long timeOfLastUpdate;
+
     public:
         KnobControl(int knobPinA, int knobPinB, int buttonPin);
         int readKnobValues();
+        int getNumberOfRotations();
         int readButtonValue();
 };

Brixcer_Box/src/KnobControl.cpp

@@ -10,8 +10,8 @@ enum position {
     END_CCW   = 5,
 };
 
-int CW_ROT  = 0x10;
-int CCW_ROT = 0xFFF0;
+int16_t CW_ROT  = 0x10;
+int16_t CCW_ROT = 0xFFF0;
 
 const int transitions[6][4] = {
     // Starting Position
@@ -38,20 +38,43 @@ KnobControl::KnobControl(int knobPinA, int knobPinB, int buttonPin) {
     pinMode(this->knobPinB, INPUT);
     pinMode(this->buttonPin, INPUT_PULLUP);
 
-    this->state = START;
+    state = START;
+    rotationCounter = 0;
 }
 
 int KnobControl::readKnobValues() {
-    // Grab state of input pins.
+    // Read the current value of the pins
     int pinstate = (digitalRead(knobPinB) << 1) | digitalRead(knobPinA);
 
-    // Determine new state from the pins and state table.
+    // Determine the current state from the transition table
     state = transitions[state & 0x7][pinstate];
 
-    // Return emit bits, ie the generated event.
+    // Return the direction of rotation (0: rotation hasn't completed, 1: CW, -1: CCW)
     return state >> 4;
 }
 
+int KnobControl::getNumberOfRotations() {
+    // Get the direction of the latest rotation
+    int direction = this->readKnobValues();
+
+    // Add the rotation to the directional rotation count
+    rotationCounter += direction;
+
+    // If the counting period has ended, send the current rotation count
+    if (millis() - timeOfLastUpdate > ROTATION_COUNT_INTERVAL_MS) {
+        // Get the number of directional rotations
+        int rotations = rotationCounter;
+
+        // Reset rotation counter
+        rotationCounter = 0;
+        timeOfLastUpdate = millis();
+
+        return rotations;
+    }
+
+    return 0;
+}
+
 int KnobControl::readButtonValue() {
     // Check if this button was the activated one
     if (!digitalRead(buttonPin)) {

Brixcer_Box/src/main.cpp

@@ -39,7 +39,7 @@ LedControl* leds = (LedControl*) malloc(sizeof(LedControl) * KnobCount);
 //MediaControl mediaControl(PlayPause, Previous, Next);
 
 // Define array for Serial input
-const int numChars = 33; // 32 chars + 1 for `\0`
+const int numChars = 33; // 32 chars + 1 for \0
 char receivedChars[numChars];
 
 // Define Serial interface
@@ -162,7 +162,7 @@ void buttonClick() {
 
 void knobPinTrigger() {
     for (int i = 0; i < KnobCount; i++) {
-        int value = knobs[i].readKnobValues();
+        int value = knobs[i].getNumberOfRotations();
         if (value != 0) {
             sendData(i, 0, value);
         }