#include <NewPing.h>
	
 // Definition of pins and maximum distance
 #define TRIGGER_PIN  D9   // GPIO pin for sensor Trigger pin
 #define ECHO_PIN     D10   // GPIO pin for sensor Echo pin
 #define MAX_DISTANCE 30 // Maximum distance to measure in centimeters
 #define MIN_DISTANCE 5   // Minimum distance when the container is full (adjust according to your needs)
 #define LEVEL_RANGE  (MAX_DISTANCE - MIN_DISTANCE) // Range of levels
	
 NewPing sonar(TRIGGER_PIN, ECHO_PIN, MAX_DISTANCE); // Sensor initialization
	
 void setup() {
 Serial.begin(115200); // Serial communication initialization
		  }
	
void loop() {
delay(1900); // Wait one second between measurements
			
unsigned int distance = sonar.ping_cm(); // Measure distance in centimeters
			
if (distance == 0 || distance > MAX_DISTANCE) {
Serial.println("Out of range"); // If the distance is 0 or greater than the maximum distance, indicate it's out of range
} 
else 
{
 // Calculate relative fill level based on the measured distance
int level = map(distance, MIN_DISTANCE, MAX_DISTANCE, 100, 0); // Map distance to a fill percentage
Serial.print("Kibble level: ");
Serial.print(level);
Serial.println("%"); // Print kibble level
			}
		  }