#define Echo 6 
#define Trig 5
long getTime()
{
  digitalWrite(Trig, HIGH);
  delayMicroseconds(10);
  digitalWrite(Trig, LOW);
  return pulseIn(Echo,HIGH);
}

void initChaoShengBo()
{
  pinMode(Echo, INPUT);
  pinMode(Trig, OUTPUT);
}
void setup() {
  // put your setup code here, to run once:
 initChaoShengBo();
 Serial.begin(9600);
 pinMode(7, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
float dis;
dis=getTime()/58;
Serial.print(dis);
Serial.println("cm");
delay(50);

if(dis>=50)
 digitalWrite(7, HIGH);
else
 digitalWrite(7, LOW);
}