#include <Arduino.h>
unsigned int EchoPin = 6;
unsigned int TrigPin = 7;
unsigned long Time_Echo_us = 0;
//Len_mm_X100 = length*100
unsigned long Len_mm_X100 = 0;
unsigned long Len_Integer = 0; //
unsigned int Len_Fraction = 0;

void setup()
{
    Serial.begin(115200);
    pinMode(EchoPin, INPUT);
    pinMode(TrigPin, OUTPUT);
}
void loop()
{
    digitalWrite(TrigPin, HIGH);
    delayMicroseconds(50);
    digitalWrite(TrigPin, LOW);
    Time_Echo_us = pulseIn(EchoPin, HIGH);
    if((Time_Echo_us < 60000) && (Time_Echo_us > 1))
    {
        Len_mm_X100 = (Time_Echo_us*34)/2;
        Len_Integer = Len_mm_X100/100;
        Len_Fraction = Len_mm_X100%100;
        Serial.print("Present Length is: ");
        Serial.print(Len_Integer, DEC);
        Serial.print(".");
        if(Len_Fraction < 10)
            Serial.print("0");
        Serial.print(Len_Fraction, DEC);
        Serial.println("mm");
    }
    delay(1000);
}