Password inserita da Keypad.

La libreria Password permette di inserire una password da keypad.

      
      
      #include <Password.h> //http://www.arduino.cc/playground/uploads/Code/Password.zip
      #include <Keypad.h> //http://www.arduino.cc/playground/uploads/Code/Keypad.zip
      #include <LiquidCrystal.h>
    
      Password password = Password( "1234" );
    
      LiquidCrystal lcd(8, 9, 10, 11, 12, 13);//pin ARDUINO MEGA 2560
    
      const byte RIGHE = 4; 
      const byte COLONNE = 4; 
      
      char keys[RIGHE][COLONNE] = {{'1','2','3','A'},
                                   {'4','5','6','B'},
                                   {'7','8','9','C'},
                                   {'F','0','E','D'}};
      
      byte rowPins[RIGHE]   = {14, 15, 16, 17}; //pin ARDUINO MEGA 2560
      byte colPins[COLONNE] = {18, 19, 20, 21};;//pin ARDUINO MEGA 2560

      Keypad keypad = Keypad( makeKeymap(keys), rowPins, colPins, RIGHE, COLONNE );
      
      void setup()
           { lcd.begin(20, 4); 
             keypad.addEventListener(keypadEvent); }
      
     
      void loop(){
     
        keypad.getKey();
        lcd.setCursor(0, 0);
        lcd.print("Ins.Codice e press F");
   
      }//-------------Fine LOOP------------------------------
      
      void keypadEvent(KeypadEvent eKey){
           switch ( keypad.getState())
                  { case PRESSED:
                    switch ( eKey )
                           { case 'F': checkPassword(); 
                             break;
                            case 'E': password.reset();
                             break;
                            default: password.append(eKey);}}
      }//------------ FINE Void -------------------------------
      
      void checkPassword() {
           if ( password.evaluate())
              { lcd.setCursor(0, 1);
                lcd.print("Impianto Inserito   "); }
          else
              { lcd.setCursor(0, 1);
                lcd.print("Codice Errato        ");   }
     
      }//------------ FINE Void -------------------------------

Scrittura su LCD 16x2 comp. HD44780

Collegare il perno centrale di due potenziometri da 47K su A1 ed A2


NOTA: Occorre la cartella di libreria LiquidCrystal.

      /*
      lcd.begin( numero caratteri, numero righe)
               (16,2) 16 caratteri;2 righe.
                   
      lcd.clear(); cancella il valore. La sovr-
         apposizione di un nuovo valore
         di 3 cifre su un valore di 4 
         cifre genera errore di lettura.
         1023 (prima lettura) e 628 2a let-
         tura risulterà 6283
       
      lcdSetCursor (numero cella, numero riga)
         num. cella: 0= 1a cella; 16a= cella
         num. riga:  0=prima riga; 1=seconda riga)
         lcdSetcursor(9,1); cursore su cella 9, 2a riga
         
      lcd.print("SENSORE");
      lcd.print(value);   
          Scrive su LCD il valore dopo la scritta
          SENSORE
      */

       #include <LiquidCrystal.h>
      
      LiquidCrystal lcd(8, 9, 10, 11, 12, 13);
      //  pin LCD       RS E  D4   D5 D6  D7
     
      void setup() 
      
          { lcd.begin(16, 2); }
      
      void loop()
     
           { lcd.setCursor(0, 0);
             lcd.print("Hello World");
             lcd.setCursor(6, 1);
             lcd.print("Ciao Mondo"); }

Scrittura su LCD 20x4 QC2004A

Basta modificare lcd.begin(16, 2) in lcd.begin (20, 4)

       #include <LiquidCrystal.h>
      
      LiquidCrystal lcd(8, 9, 10, 11, 12, 13);
      //  pin LCD       RS E  D4   D5 D6  D7
     
      void setup() 
      
          { lcd.begin(20, 4); }
      
      void loop() {
       
             lcd.setCursor(0, 0);
             lcd.print("Prima riga");
             lcd.setCursor(0, 1);
             lcd.print("Seconda riga");
             lcd.setCursor(0, 2);
             lcd.print("Terza riga");
             lcd.setCursor(0, 3);
             lcd.print("Quarta riga ");
         }