#define echoPin 6
#define trigPin 7
#define buzzerPin 8

int maximumRange = 50;
int minimumRange = 0;

void setup() {
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(buzzerPin, OUTPUT);

}

void loop() {
  int olcum = mesafe(maximumRange, minimumRange);
  melodi(olcum*10);

}

int mesafe(int maxrange, int minrange);
{
  long duration, distance;

  digitalWrite(trigPin,LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin,HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin,LOW);

  duration = pulseIn(echoPin, HIGH);
  distance = duration / 58.2;
  delay(50);
  if(distance >= maxrange || distance <= minrange)
  return 0;
  return distance;

}

int melodi(int dly)
{
  tone(buzzerPin, 440);
  delay(dly);
  noTone(buzzerPin);
  delay(dly);
}

Arduino:1.8.9 (Windows 10), Kart:"Arduino/Genuino Uno"

C:\Users\Yunus Şimşek\Documents\Arduino\sketch_jul29a\sketch_jul29a.ino: In function 'void loop()':

sketch_jul29a:16:46: error: 'mesafe' was not declared in this scope

C:\Users\Yunus Şimşek\Documents\Arduino\sketch_jul29a\sketch_jul29a.ino: At global scope:

sketch_jul29a:22:1: error: expected unqualified-id before '{' token

exit status 1
'mesafe' was not declared in this scope

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