User:Laurier Rochon/prototyping/clapping music with arduino LED screen pushbutton

Clapping music + shifting pattern /w Arduino

Constant pattern + shifting pattern using a single channel piezo and values subtraction. I didn't want to use two piezos/speakers as that would simply duplicate the code into something slightly less interesting. Result of the subtraction of the two patterns is printed to the screen and loops.

Got some help from http://www.ladyada.net/learn/lcd/charlcd.html

Hard

• 16-pin 16x1 LED display
• pushbutton
• piezo
• 3 resistors
• breadboard
• Arduino 168 Diecimila

{{#ev:vimeo|16137046|640}}

Soft

This code needs more work (i.e. more modular). Some things are hard-coded and no comments are in yet...more to come. I had much trouble converting my string/int to char to send to the LCD screen. Atoi wouldn't do it and the built-in C functions wouldn't do it = ugly IF.

//LED screen library
#include <LiquidCrystal.h>

//globals
const int numRows = 2;
const int numCols = 16;
int a=0;
int row=0;
int lpos=0;

int pos1=0;
int pos2=0;

String txt="NOT PLAYING";
int lentxt=txt.length();

//pins on Arduino
LiquidCrystal lcd(4, 5, 0, 1, 2, 3);

//normal pattern
String pat = "999099090990";
//shifting pattern
String mov = "555055050550";
//pushbutton pin
const int buttonPin = 9;
//start in OFF position
int buttonState = 0;

void setup() {
  //initialize stuffs
  pinMode(buttonPin, INPUT);  
  lcd.begin(numCols,numRows);
}

void loop() {   
  //read the button
  buttonState = digitalRead(buttonPin);
  //if it's pressed
    if (buttonState == HIGH) {     
      //get the pattern length
      int patlen = pat.length();

      for (int p=0; p<patlen; p++) {
        
        //tone stuff
        
        int val1 = pat.charAt(p);
        int val2 = mov.charAt(p);
        //compute the difference in value
        int diff = (val1-val2)*100;
        //play it  
        tone(8, diff, 10);
        
        //starting the shifting
        String first = mov.charAt(0);
        String second = "";

        //is there an easier way to do this? I don't know
        for(int i=1;i<12;i++){
          second.concat(mov.charAt(i));
        }
        
 
        diff = diff/100;
        
        //put the new mov value together
        mov = second+first;
        
        //LED stuff
        //if you're in the 8 first spots, you should be row #1. otherwise row #2
        //this hack was needed because my screen is 16x1, not 16x2
        if(a<8){row=0;}else{row=1;}

        //if you get to spot 9, go back to 0
        if(lpos==8){lpos=0;}
        
        //set the cursor on the LED
        lcd.setCursor(lpos,row);
        
        //simply could NOT manage to print the byte directly, this is retarded
        if (diff == 4) {
          lcd.print('4', BYTE); 
        }else{
          lcd.print('5', BYTE);             
        }
        
        //done. increment the values
        lpos++;
        a++;
        if(a==16){a=0;lcd.clear();}
        delay(200);
      }
    
    }else{
      //if the button is not 'on', then scroll through this text
      txt="NOT PLAYING";
      readtext();
    }
  
  

}

void readtext(){
  for (int lindex = 0; lindex <= lentxt; lindex++) {
     
      //same here
      if(a<8){row=0;}else{row=1;}
      if(lpos==8){lpos=0;}

      lcd.setCursor(lpos,row);
      lcd.print(txt.charAt(lindex), BYTE);
      delay(100); 

      lpos++;
      a++;
      
      if(a==16){ a=0; lcd.clear();
      }  
   }
   lcd.clear(); 
}