Occupancy Counter with PIR Sensors

import RPi.GPIO as GPIO
import time

GPIO.setmode(GPIO.BCM)
GPIO.setwarnings(False)

SENSOR_OUTSIDE = 17
SENSOR_INSIDE = 27

GPIO.setup(SENSOR_OUTSIDE, GPIO.IN, pull_up_down=GPIO.PUD_DOWN)
GPIO.setup(SENSOR_INSIDE, GPIO.IN, pull_up_down=GPIO.PUD_DOWN)

occupancy = 0

def wait_for_clear():
    while GPIO.input(SENSOR_OUTSIDE) or GPIO.input(SENSOR_INSIDE):
        time.sleep(0.1)

def count_people():
    global occupancy
    
    while True:
        # Check for entry (outside sensor first)
        if GPIO.input(SENSOR_OUTSIDE):
            time.sleep(0.2)
            
            # Wait for inside sensor
            timeout = 0
            while not GPIO.input(SENSOR_INSIDE) and timeout < 50:
                time.sleep(0.1)
                timeout += 1
            
            if GPIO.input(SENSOR_INSIDE):
                occupancy += 1
                print(f"Person entered. Occupancy: {occupancy}")
                wait_for_clear()
        
        # Check for exit (inside sensor first)
        if GPIO.input(SENSOR_INSIDE):
            time.sleep(0.2)
            
            # Wait for outside sensor
            timeout = 0
            while not GPIO.input(SENSOR_OUTSIDE) and timeout < 50:
                time.sleep(0.1)
                timeout += 1
            
            if GPIO.input(SENSOR_OUTSIDE):
                occupancy = max(0, occupancy - 1)
                print(f"Person exited. Occupancy: {occupancy}")
                wait_for_clear()
        
        time.sleep(0.1)

try:
    count_people()
except KeyboardInterrupt:
    GPIO.cleanup()
    print("\nCounter stopped.")

Mount sensors on door frame sides for real-world use.