# TUI Lab 2: Pulse Wave Modulation and Serial Input

lab2_shreyas_serial_pwm

/*
* Code for cross fading 3 LEDs and then taking user input
* to increase the stepwise intensity of the corresponding LED
* r for red, b for blue, g for gree
* by: [email protected]

* License: MIT
*/

// Output
int redPin   = 9;   // Red LED,   connected to digital pin 9
int greenPin = 10;  // Green LED, connected to digital pin 10
int bluePin  = 11;  // Blue LED,  connected to digital pin 11

// Program variables
int redVal   = 255; // Variables to store the values to send to the pins
int greenVal = 0;   // Initial values are Red full, Green and Blue off
int blueVal  = 0;

int i = 0;     // Loop counter    
int wait = 50; // 50ms (.05 second) delay; shorten for faster fades
int DEBUG = 0; // DEBUG counter; if set to 1, will write values back via serial


char userInput[100]; //get user input keys
char color;

void setup()
{
  pinMode(redPin,   OUTPUT);   // sets the pins as output
  pinMode(greenPin, OUTPUT);   
  pinMode(bluePin,  OUTPUT); 

  Serial.begin(9600);  // ...set up the serial ouput on 0004 style
  
  Serial.print("Enter the command as a combination of r/g/b keys");
}

// Main program
void loop()
{
  
i += 1;      // Increment counter



  
  memset(userInput, 0, 100);
  readUserInput(userInput);
  Serial.print(userInput);

    
    
    
 for (int i=0; i<= sizeof(userInput); i++){
    
    color = userInput[i];
//    Serial.print("color");
    Serial.print(color);
   
   if (color == 'r'){
      //red key
     redVal = redVal+ 25.5;
    
     if (redVal >= 255){
        redVal = 0;
     }
      
       
      analogWrite(redPin,   redVal);   // Write current values to LED pins
      Serial.print(redVal);
      
   }
   
   if (color == 'g'){
      //red key
     greenVal = greenVal + 25.5;
    
     if (greenVal >= 255){
        greenVal = 0;
     }
     
     analogWrite(greenPin, greenVal); 
     Serial.print(redVal);
   }
   
   if (color == 'b'){
      //red key
     blueVal = blueVal+ 25.5;
    
     if (blueVal >= 255){
        blueVal = 0;
     }
    
    analogWrite(bluePin,  blueVal);
    Serial.print(redVal);  
   }
   
   if (color == 'f'){
     
    
  
   }
   
   
   
   if (DEBUG) { // If we want to read the output
    

      Serial.print(i);       // Serial commands in 0004 style
      Serial.print("\t");    // Print a tab
      Serial.print("R:");    // Indicate that output is red value
      Serial.print(redVal);  // Print red value
      Serial.print("\t");    // Print a tab
      Serial.print("G:");    // Repeat for green and blue...
      Serial.print(greenVal);
      Serial.print("\t");    
      Serial.print("B:");    
      Serial.println(blueVal); // println, to end with a carriage return
    
  }
  
   
    
  }
    

  
    analogWrite(redPin,   redVal);   // Write current values to LED pins
    analogWrite(greenPin, greenVal); 
    analogWrite(bluePin,  blueVal); 
  
  
  
  delay(wait); // Pause for 'wait' milliseconds before resuming the loop
}


void readUserInput(char *strArray){
  int i = 0;
  
  if (Serial.available()){
    while(Serial.available()){
         strArray[i] = Serial.read();
         i++;
    } 
  }else{
    return;
  }
}