// MCU BASIC: https://www.basic4mcu.com
// DateTime : 2018-04-13 오후 11:41:50
// by Ok-Hyun Park
int trigPin1=2,echoPin1=3; // 초음파#1
int trigPin2=4,echoPin2=5; // 초음파#2
int r=12,g=13;
int maximumRange=10,minimumRange=0; // 초음파 최대-최소거리 설정
int Sound=A1;                       // 피에조센서
//
const int system_time=50;                     // 전체 시스템 시간
const int ultrasonic_time=10;                 // 초음파 측정 시간
long duration1,duration2,distance1,distance2; // 펄스 시간,거리 측정용 변수
long distance1_a,distance2_a;                 // 구동연산 변수
int ultrasonic_count=2;                       // 초음파 Count만큼 감지 후 평균 값에 의해 동작 함
const long distanse_set=9;                    // 초음파 사람 감지 세팅 값
//
int mode=0,cnt=0;
//
void setup(){
  Serial.begin(9600);
  pinMode(trigPin1,OUTPUT); pinMode(echoPin1,INPUT);
  pinMode(trigPin2,OUTPUT); pinMode(echoPin2,INPUT);
  pinMode(Sound,OUTPUT); pinMode(r,OUTPUT); pinMode(g,OUTPUT);
  delay(system_time);
  digitalWrite(r,HIGH);
}
//
void loop(){
  delay(system_time); distance1_a=0; distance2_a=0;  // #1.초음파 센서 ultrasonic_count 만큼 감지 후 저장
  //
  for(int i=1; i<=ultrasonic_count; i++){                        /***초음파1 감지***/
    digitalWrite(trigPin1,HIGH); delayMicroseconds(10); digitalWrite(trigPin1,LOW);
    duration1=pulseIn(echoPin1,HIGH);  distance1=duration1/58.2; // 측정된 시간을 cm로 환산
    distance1_a=distance1_a+distance1; delay(ultrasonic_time);
  }
  for(int i=1; i<=ultrasonic_count; i++){                        /***초음파2 감지***/
    digitalWrite(trigPin2,HIGH); delayMicroseconds(10); digitalWrite(trigPin2,LOW);
    duration2=pulseIn(echoPin2,HIGH);  distance2=duration2/58.2; // 측정된 시간을 cm로 환산
    distance2_a=distance2_a+distance2; delay(ultrasonic_time);
  }
  //
  distance1=long(distance1_a/ultrasonic_count); distance2=long(distance2_a/ultrasonic_count); //#2.평균
  if(distance1>=maximumRange)distance1=maximumRange; Serial.println(distance1); //#3.초음파 측정 거리 제한
  if(distance2>=maximumRange)distance2=maximumRange; Serial.println(distance2);
  //
  if(mode==0){
    if((distance1<=distanse_set)||(distance2<=distanse_set)){ tone(A1,7000,200); Serial.println("\n"); }
  }
  if((distance1> distanse_set)||(distance2> distanse_set)){ digitalWrite(Sound,LOW); }
  //
  if(++cnt>=55){ cnt=0;
    mode^=1;
    if(mode){ digitalWrite(r, LOW); digitalWrite(g,HIGH); }
    else    { digitalWrite(r,HIGH); digitalWrite(g, LOW); }
  }  
}