15. November 2010

<pre>// Constants ------------------------------------
#define DIR 2                   // Direction Pin
#define STEP 3                  // Constant
#define LED 4                   // LED, lights up each motor rotation

// Variables ------------------------------------
int latchPin = 8;     // latch pin for the led row
int dataPin = 11;     // data pin
int clockPin = 12;    // clock pin

int steps = 0;  // number of steps read over serial communication
int sensorValue = 0;  // value of the LED sensor

// Setup ----------------------------------------
void setup() {
 pinMode(DIR, OUTPUT);         // Direction is an output
 pinMode(STEP, OUTPUT);        // Step is an output
 pinMode(LED, OUTPUT);
 pinMode(latchPin, OUTPUT);

 digitalWrite(LED, LOW);    // internal pin up

 Serial.begin(9600);

 // set led row off
 shiftOut(dataPin, clockPin, 0);
 shiftOut(dataPin, clockPin, 0);
}

// Loop -----------------------------------------
void loop() {
 digitalWrite(DIR, LOW);    // set direction

 if (Serial.available() >= 1) {  // if serial communication is available
 steps = Serial.read() -48;  // read the number of steps and convert the char into the equivalent number
 Serial.println(steps);

 // motorrrr
 for (int j=0; j<steps; j++) {
 Serial.println(j);
 digitalWrite(LED, HIGH);    // turn single led on
 stepOnce();                 // do 1 step
 delay(850);                 // time one marble takes from the top to the led row
 digitalWrite(LED, LOW);
 light();      // ledsssss
 }
 }
}

// Function Definition ---------------------------
void stepOnce() {                   // motor rotation
 for (int i=0; i<=24; i++) {
 digitalWrite(STEP, HIGH);
 delay(10);
 digitalWrite(STEP, LOW);
 delay(1);
 }
}

void light () {                      // led row
 for (int j = 0; j < 8; j++) {
 //ground latchPin and hold low for as long as you are transmitting
 digitalWrite(latchPin, 0);
 shiftOut(dataPin, clockPin, 0);
 lightShiftPinA(j);
 digitalWrite(latchPin, 1);
 delay(50);
 }
 for (int j = 0; j < 8; j++) {
 //ground latchPin and hold low for as long as you are transmitting
 lightShiftPinA(j);
 digitalWrite(latchPin, 0);
 shiftOut(dataPin, clockPin, 0);
 digitalWrite(latchPin, 1);
 delay(50);
 }

}

void lightShiftPinA(int p) {
 int pin;
 pin = 1<< p;
 shiftOut(dataPin, clockPin, pin);
}

// the heart of the program
void shiftOut(int myDataPin, int myClockPin, byte myDataOut) {
 // This shifts 8 bits out MSB first,
 //on the rising edge of the clock,
 //clock idles low

 //internal function setup
 int i=0;
 int pinState;
 pinMode(myClockPin, OUTPUT);
 pinMode(myDataPin, OUTPUT);

 //clear everything out just in case to
 //prepare shift register for bit shifting
 digitalWrite(myDataPin, 0);
 digitalWrite(myClockPin, 0);

 //for each bit in the byte myDataOut�
 //NOTICE THAT WE ARE COUNTING DOWN in our for loop
 //This means that %00000001 or "1" will go through such
 //that it will be pin Q0 that lights.
 for (i=7; i>=0; i--)  {
 digitalWrite(myClockPin, 0);

 //if the value passed to myDataOut and a bitmask result
 // true then... so if we are at i=6 and our value is
 // %11010100 it would the code compares it to %01000000
 // and proceeds to set pinState to 1.
 if ( myDataOut & (1<<i) ) {
 pinState= 1;
 }
 else {
 pinState= 0;
 }

 //Sets the pin to HIGH or LOW depending on pinState
 digitalWrite(myDataPin, pinState);
 //register shifts bits on upstroke of clock pin
 digitalWrite(myClockPin, 1);
 //zero the data pin after shift to prevent bleed through
 digitalWrite(myDataPin, 0);
 }

 //stop shifting
 digitalWrite(myClockPin, 0);
}