#include <Wire.h> 
#include <LiquidCrystal_I2C.h> 
LiquidCrystal_I2C lcd(0x27,16,2);  

int Echo = 2;                       
int Trig = 0;                       
float Get_Distance()//测出距离
{
  digitalWrite(Trig, LOW);   
  delayMicroseconds(2);
  digitalWrite(Trig, HIGH);  
  delayMicroseconds(10);
  digitalWrite(Trig, LOW);    
  float Ldistance = pulseIn(Echo, HIGH,5000);  
  Ldistance = Ldistance / 5.8 / 10; 
  Serial.print("超声波的距离是:3");
  Serial.println(Ldistance);     
  return Ldistance;
}
void setup() 
{
  lcd.init();                 
  lcd.backlight();            
  
  pinMode(Echo, INPUT);        
  pinMode(Trig, OUTPUT);       
  Serial.begin(9600);
}

void loop() 
{
  Get_Distance();              
  LCDShow(Get_Distance());                                                
  delay(500);
}void LCDShow(float Ldistance)
{
  lcd.setCursor(0,0);         
  lcd.print("Ldistance");     
  lcd.setCursor(0,1);
  lcd.print(Ldistance);
}