Using Ultrasonic Range Finder SRF02 as Motion Detector

No comments for all my mistakes on code...
The problem was just linked with a wrong position of variable declaration...
Now I hope I can use this on Processing
Great thanks for your support

#include <Wire.h>

//definition of pin on Arduino board
const int PIR1 = 2;
const int PIR2 = 3;
const int LED1 = 4;
const int LED2 = 5;
const int pinPot=A0;

//Definition of variables to use
int val1 = 0;             //PIR1 value
int val2 = 0;             //PIR2 value
int reading = 0;          //US value
int oldreading = 0;       //oldUS value
int count = 0;            //counter to keep LED turned on 
int calibrationTime = 5;  //calibration time of PIR sensors

void setup()
{
  Wire.begin();          // start the I2C bus

  Serial.begin(9600);    // open the serial port:
  
  //Definition of input/output values
  pinMode(PIR1,INPUT);
  pinMode(PIR2,INPUT);
  pinMode(LED1,OUTPUT);
  pinMode(LED2,OUTPUT);

  
  //give the sensor some time to calibrate
  Serial.println("Sensor Calibration in Progress");
  Serial.println("------------------------------");
  
  for(int i = 0; i < calibrationTime; i++){
    Serial.print(".");
    digitalWrite(LED1, HIGH);
    delay(250);
    digitalWrite(LED2, HIGH);
    delay(250);
    digitalWrite(LED1, LOW);
    delay(250);
    digitalWrite(LED2, LOW);
    delay(250);
  }

  Serial.println("");
  Serial.println("Sensor Calibration Completed");
  Serial.println("Sensor Reading Active");
  delay(100);
}

void loop()
{
passiveIR();
ultrasonic();
presence();
}

void passiveIR()
{
  val1 = digitalRead(PIR1);
  val2 = digitalRead(PIR2);  
}

void ultrasonic()
{
  // step 1: instruct sensor to read centimeters
  Wire.beginTransmission(112); // transmit to device #112 (0x70)
                               // the address specified in the datasheet is 224 (0xE0)
                               // but i2c adressing uses the high 7 bits so it's 112
  Wire.write(byte(0x00));      // sets register pointer to the command register (0x00)  
  Wire.write(byte(0x51));      // command sensor to measure in "inches" (0x50) 
                               // use 0x51 for centimeters
                               // use 0x52 for ping microseconds
  Wire.endTransmission();      // stop transmitting

  // step 2: wait for readings to happen
  delay(70);                   // datasheet suggests at least 65 milliseconds

  // step 3: instruct sensor to return a particular echo reading
  Wire.beginTransmission(112); // transmit to device #112
  Wire.write(byte(0x02));      // sets register pointer to echo #1 register (0x02)
  Wire.endTransmission();      // stop transmitting

  // step 4: request reading from sensor
  Wire.requestFrom(112, 2);    // request 2 bytes from slave device #112

  // step 5: receive reading from sensor
  if(2 <= Wire.available())    // if two bytes were received
  {
    oldreading = reading;
    reading = Wire.read();    // receive high byte (overwrites previous reading)
    reading = reading << 8;   // shift high byte to be high 8 bits
    reading |= Wire.read();   // receive low byte as lower 8 bits
  }

  delay(25);                 // wait before next reading:
}

void presence()
{
  int f = reading - oldreading; 
  
  if((val1 == HIGH) && (val2 == HIGH) && (f < 15)){
    Serial.print('1');
    Serial.print(';');

  }
  if((val1 == LOW) || (val2 == LOW) || f >15){
    Serial.print('0');
    Serial.print(';');
    count = 1;
    
    if(count > 0){
    count=count+1;
    digitalWrite(LED1, HIGH);
    }
    
    if(count == 50){  
    digitalWrite(LED1, LOW);
    count = 0; 
    }
  } 
}