Digital Meter

//by t.vajed

#include <LiquidCrystal.h>
int echoPin=5;
int pingPin=6;
// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(12, 11, 10, 9, 8, 7);

void setup() {
  // set up the LCD's number of columns and rows:
  lcd.begin(16, 2);
  // Print a message to the LCD.
  lcd.clear();
  delay(150);
  lcd.print("digital, meter");
  delay(2500);
  lcd.clear();
  delay(150);
  pinMode(pingPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(A0,INPUT_PULLUP);
  pinMode(A1,INPUT_PULLUP);
}

void loop() {
//srf05 works in two mode in this project, first capture
   while(digitalRead(A0)==0){
    lcd.clear();
    lcd.print("capture mode");
    delay(200);
    if(digitalRead(A1)==0){
     //srf starts working 
     digitalWrite(pingPin, 0);
     delayMicroseconds(5);
     digitalWrite(pingPin, 1);
     delayMicroseconds(5);
     digitalWrite(pingPin, 0);
     int duration=pulseIn(echoPin, HIGH);
     lcd.clear();
     lcd.print(duration/58);
     lcd.print(" cm");
     lcd.setCursor(0,1);
     lcd.print(duration/74/2);
     lcd.print(" in");
     delay(3500);
    }
  }
  //scanning mode of srf
   digitalWrite(pingPin, 0);
   delayMicroseconds(5);
   digitalWrite(pingPin, 1);
   delayMicroseconds(5);
   digitalWrite(pingPin, 0);
   int duration=pulseIn(echoPin, HIGH);
   lcd.print(duration/58);
   lcd.print(" cm");
   lcd.setCursor(0,1);
   lcd.print(duration/74/2);
   lcd.print(" in");
   delay(1000);
   lcd.clear();
}