#include <SoftwareSerial.h>

SoftwareSerial mySerial(11,10);
unsigned char data[4];
int distance;
int i;

void setup()
{
  Serial.begin(9600);
  mySerial.begin(9600); 
}

void loop()
{
  while (i < 4)
  {
    if(mySerial.available())
    {
      data[i]=mySerial.read();
      i++;
    }
  }

  i = 0;
  int sum=(data[0] + data[1] + data[2]) & 0xFF;

  if(data[0] == 0xFF && sum == data[3])
  {
    distance=(data[1]<<8)+data[2];
    Serial.print(distance/10);
    Serial.println(" cm");
  }
}
ME007YSBreakout