/* Using the HEF4794B LED Driver from Philips
 * Modified from script at http://arduino.cc/en/Tutorial/LEDDriver 
 * by David Cuartielles, Marcus Hannerstig
 *
 * Multi 4794s Version 2: Using an Array to animate a series of 16 on and off LEDs
 */
// Setup variables       
int data = 9;            // - Data output, connected to pin 2 on the first 4794
int strobe = 8;          // - Strobe output, connected to pin 1 on each 4794
int clock = 10;          // - Clock output, connected to pin 3 on each 4794.
int eo = 11;             // - Output Enable output, connected to pin 15 on each 4794
int potPin = 0;          // - Potenitometer Analog input pin on the Arduino, used for variable timing
               // LED positions
               // Second Set        First Set
               // 7 6 5 4 3 2 1 0   7 6 5 4 3 2 1 0          
int myArray1[] = {0,0,1,0,0,1,0,0,  0,0,1,0,0,1,0,0};   
int myArray2[] = {1,0,0,1,0,0,1,0,  0,1,0,0,1,0,0,1};   
int myArray3[] = {0,1,0,0,1,0,0,1,  1,0,0,1,0,0,1,0};   
              // Each array holds a chase lighting animation position, but with the first and second  
              // halves of the array animating in opposite directions.
int arrayCount = 1; // A variable to track which array will be used in the Main Loop
int myArray[15];    // An empty array with 16 positions to hold the contents of the 3 arrays above          
                         
// Standard initializing of pins 
void setup() {
  pinMode(data, OUTPUT);
  pinMode(clock, OUTPUT);
  pinMode(strobe, OUTPUT);
  pinMode(eo, OUTPUT);
  Serial.begin(9600);
}                                

// Function to pulse the clock
void PulseClock(void) {          
  digitalWrite(clock, LOW);       
  delayMicroseconds(40);         
  digitalWrite(clock, HIGH);     
  delayMicroseconds(40);        
  digitalWrite(clock, LOW);      
}                       

// The Main Loop
void loop() {                      
   // A cascading set of if then statments to move thru the three different arrays
  if (arrayCount == 1) {                        // When arrayCount is 1, step thru myArray and        
    for (int count = 0; count < 16; count++) {  // set each of its array positions to the value
      myArray[count] = myArray1[count];         // in the same position in myArray1
    }
  }else if (arrayCount == 2) {                  // Likewise for myArray2
    for (int count = 0; count < 16; count++) {
      myArray[count] = myArray2[count];
    }
  }else {                                       // And for myArray3
    for (int count = 0; count < 16; count++) {
      myArray[count] = myArray3[count];
    }
  }   
  // Move thru 1,2 and 3 and back to 1 again each cycle of the Main Loop
  if (arrayCount < 3) {                        
    arrayCount++;
  }else{
    arrayCount = 1;
  }  
  for (int count = 0; count < 16; count++) { 
  // Step thru the values in myArray with count. 
    digitalWrite(data,myArray[count]); 
    if (count == 15){            
      digitalWrite(eo, LOW);      
      digitalWrite(strobe, HIGH); 
      PulseClock();               
      digitalWrite(eo, HIGH);    
      digitalWrite(strobe, LOW);  
    } else {
      PulseClock();               
    }
  }
  delay(analogRead(potPin));      // Use the value in the analog input from the potentiometer as a timer 
}