Código IDE C5

/* ---------------------------------------------------------

*     |  Arduino Experimentation Kit Example Code             |
*     |  CIRC-05 .: 8 More LEDs :. (74HC595 Shift Register)   |
*     ---------------------------------------------------------
* 
* We have already controlled 8 LEDs however this does it in a slightly
* different manner. Rather than using 8 pins we will use just three
* and an additional chip.
*
*
*/

//Pin Definitions //Pin Definitions //The 74HC595 uses a serial communication //link which has three pins int data = 2; int clock = 3; int latch = 4;

//Used for single LED manipulation int ledState = 0; const int ON = HIGH; const int OFF = LOW;

/*

* setup() - this function runs once when you turn your Arduino on
* We set the three control pins to outputs
*/

void setup() {

 pinMode(data, OUTPUT);
 pinMode(clock, OUTPUT);  
 pinMode(latch, OUTPUT);  

}

/*

* loop() - this function will start after setup finishes and then repeat
* we set which LEDs we want on then call a routine which sends the states to the 74HC595
*/

void loop() // run over and over again {

 int delayTime = 100; //the number of milliseconds to delay between LED updates
 for(int i = 0; i < 256; i++){
  updateLEDs(i);
  delay(delayTime); 
 }

}

/*

* updateLEDs() - sends the LED states set in ledStates to the 74HC595
* sequence
*/

void updateLEDs(int value){

 digitalWrite(latch, LOW);     //Pulls the chips latch low
 shiftOut(data, clock, MSBFIRST, value); //Shifts out the 8 bits to the shift register
 digitalWrite(latch, HIGH);   //Pulls the latch high displaying the data

}

/*

* updateLEDsLong() - sends the LED states set in ledStates to the 74HC595
* sequence. Same as updateLEDs except the shifting out is done in software
* so you can see what is happening.
*/ 

void updateLEDsLong(int value){

 digitalWrite(latch, LOW);    //Pulls the chips latch low
 for(int i = 0; i < 8; i++){  //Will repeat 8 times (once for each bit)
 int bit = value & B10000000; //We use a "bitmask" to select only the eighth 
                              //bit in our number (the one we are addressing this time through
 value = value << 1;          //we move our number up one bit value so next time bit 7 will be
                              //bit 8 and we will do our math on it
 if(bit == 128){digitalWrite(data, HIGH);} //if bit 8 is set then set our data pin high
 else{digitalWrite(data, LOW);}            //if bit 8 is unset then set the data pin low
 digitalWrite(clock, HIGH);                //the next three lines pulse the clock pin
 delay(1);
 digitalWrite(clock, LOW);
 }
 digitalWrite(latch, HIGH);  //pulls the latch high shifting our data into being displayed

}

//These are used in the bitwise math that we use to change individual LEDs //For more details http://en.wikipedia.org/wiki/Bitwise_operation int bits[] = {B00000001, B00000010, B00000100, B00001000, B00010000, B00100000, B01000000, B10000000}; int masks[] = {B11111110, B11111101, B11111011, B11110111, B11101111, B11011111, B10111111, B01111111}; /*

* changeLED(int led, int state) - changes an individual LED 
* LEDs are 0 to 7 and state is either 0 - OFF or 1 - ON
*/
void changeLED(int led, int state){
  ledState = ledState & masks[led];  //clears ledState of the bit we are addressing
  if(state == ON){ledState = ledState | bits[led];} //if the bit is on we will add it to ledState
  updateLEDs(ledState);              //send the new LED state to the shift register
}