// ==================================================== // ArduExams Copyright(C) 2018 Furkan Türkal // This program comes with ABSOLUTELY NO WARRANTY; This is free software, // and you are welcome to redistribute it under certain conditions; See // file LICENSE, which is part of this source code package, for details. // ==================================================== #define PIN_HCSR04_TRIG 8 #define PIN_HCSR04_ECHO 9 #define PIN_LED1 4 #define PIN_LED2 5 #define PIN_LED3 6 #define PIN_LED4 7 float HCSR04_Duration = 0.0; float HCSR04_Distance = 0.0; void setup() { pinMode(PIN_HCSR04_TRIG, OUTPUT); pinMode(PIN_HCSR04_ECHO, INPUT); pinMode(PIN_LED1, OUTPUT); pinMode(PIN_LED2, OUTPUT); pinMode(PIN_LED3, OUTPUT); pinMode(PIN_LED4, OUTPUT); Serial.begin(9600); } void loop() { digitalWrite(PIN_HCSR04_TRIG, LOW); delayMicroseconds(2); digitalWrite(PIN_HCSR04_TRIG, HIGH); delayMicroseconds(10); digitalWrite(PIN_HCSR04_TRIG, LOW); HCSR04_Duration = pulseIn(PIN_HCSR04_ECHO, HIGH); HCSR04_Distance = (HCSR04_Duration / 2) / 29.1; if (HCSR04_Distance >= 200 || HCSR04_Distance <= 0){ digitalWrite(PIN_LED1, LOW); digitalWrite(PIN_LED2, LOW); digitalWrite(PIN_LED3, LOW); digitalWrite(PIN_LED4, LOW); Serial.println("Out of range"); } else { if(HCSR04_Distance > 0 && HCSR04_Distance <= 15){ digitalWrite(PIN_LED1, HIGH); digitalWrite(PIN_LED2, HIGH); digitalWrite(PIN_LED3, HIGH); digitalWrite(PIN_LED4, HIGH); } else if(HCSR04_Distance > 15 && HCSR04_Distance <= 30){ digitalWrite(PIN_LED1, HIGH); digitalWrite(PIN_LED2, HIGH); digitalWrite(PIN_LED3, HIGH); digitalWrite(PIN_LED4, LOW); } else if(HCSR04_Distance > 30 && HCSR04_Distance <= 40){ digitalWrite(PIN_LED1, HIGH); digitalWrite(PIN_LED2, HIGH); digitalWrite(PIN_LED3, LOW); digitalWrite(PIN_LED4, LOW); } else if(HCSR04_Distance > 40 && HCSR04_Distance <= 60){ digitalWrite(PIN_LED1, HIGH); digitalWrite(PIN_LED2, LOW); digitalWrite(PIN_LED3, LOW); digitalWrite(PIN_LED4, LOW); } Serial.print("Distance = "); Serial.print(HCSR04_Distance); Serial.print(" cm"); Serial.println(); } delay(1000); }