Be sure to download the following MP3 files so that you can hear the samples playing. These sounds we are using came from MATTIX at freesound.org .
We can use wget to pull down the audio files and code directly to the Pi we are working on. ssh into your pi and run the following command to pull down the two audio files and example python code.
$ wget https://github.com/adafruit/Adafruit_Learning_System_Guides/raw/master/Sitcom_SFX_Door_Trigger/enter.wav $ wget https://github.com/adafruit/Adafruit_Learning_System_Guides/raw/master/Sitcom_SFX_Door_Trigger/exit.wav $ wget https://raw.githubusercontent.com/adafruit/Adafruit_Learning_System_Guides/master/Sitcom_SFX_Door_Trigger/Sitcom_SFX_Door_Trigger.py
If you are using the 1/8inch audio jack, you'll need to ssh into your Pi and run this command to route audio to that output
$ sudo amixer cset numid=3 1
# SPDX-FileCopyrightText: 2019 Mikey Sklar for Adafruit Industries
#
# SPDX-License-Identifier: MIT
import time
import board
from digitalio import DigitalInOut, Direction
import pygame.mixer
# setup inputs
door_switch_pin = board.D23
motion_sensor_pin = board.D24
door = DigitalInOut(door_switch_pin)
door.direction = Direction.INPUT
motion = DigitalInOut(motion_sensor_pin)
motion.direction = Direction.INPUT
# setup output LED indicators
motion_led_pin = board.D18
door_led_pin = board.D25
door_led = DigitalInOut(door_led_pin)
door_led.direction = Direction.OUTPUT
door_led.value = False
motion_led = DigitalInOut(motion_led_pin)
motion_led.direction = Direction.OUTPUT
motion_led.value = False
prev_door = False
# audio settings
pygame.mixer.init(44100, -16, 2, 1024)
# sound files expect to be in the same directory as script
enter_sound = pygame.mixer.Sound("./enter.wav")
exit_sound = pygame.mixer.Sound("./exit.wav")
while True:
# toggle door LED based on door sensor
if door.value:
door_led.value = True
else:
door_led.value = False
# toggle motion LED based on motion (PIR) sensor
if motion.value:
motion_led.value = True
else:
motion_led.value = False
# When the door is opened, if there is movement outside,
# It means that someone is entering.
# If not, someone is exiting.
if door.value and not prev_door:
if motion.value:
enter_sound.play()
else:
exit_sound.play()
prev_door = door.value
time.sleep(0.01)
Run the code on your Pi and make sure it works. If the green LED is lit (motion detected) it should play enter.wav when the door switch is opened, and exit.wav if there is no motion detected.
$ sudo python3 ./Sitcom_SFX_Door_Trigger.py
The PIR sensor has two physically adjustable potentiometers on it, I've found it's best to set it to max sensitivity and minimum retrigger time. For more info, check out the PIR tutorial
Now lets mount it!
