Raspberry Pi Workshop Kit Tutorials - 9 Passive Infrared Sensor

Welcome to the Raspberry Pi Workshop Tutorials, brought to you by ModMyPi, BuyaPi.ca, and PiShop.us. In this series, we’ll demonstrate nine projects that can be made using the YouTube Workshop Kit for Raspberry Pi. These projects are a great way to familiarize yourself with the Pi’s input and output functions, as well as creating programs in Python that we’ll use to control the Pi’s hardware.

Tutorial 9 - Passive Infrared Sensor
Circuit Diagram: http://www.modmypi.com/download/led_button_buzzer_temp_ldr_pir_bb.png
Tutorial 9 Download: http://www.modmypi.com/download/youtube_workshop_9_pir.pdf
View Tutorial Online: https://www.modmypi.com/blog/youtube-workshop-kit/gpio-and-python-99-pir

*** Code Used In This Tutorial ***

#!/usr/bin/python

import RPi.GPIO as GPIO
from time import sleep

GPIO.setmode(GPIO.BCM)
GPIO.setup(27,GPIO.OUT)

GPIO_PIR = 7

print "PIR Module Test (CTRL-C to exit)"

# Set pin as input
GPIO.setup(GPIO_PIR,GPIO.IN)

Current_State = 0
Previous_State = 0

try:
print "Waiting for PIR to settle ..."
# Loop until PIR output is 0
while GPIO.input(GPIO_PIR)==1:
Current_State = 0
print " Ready"
# Loop until users quits with CTRL-C
while True :
# Read PIR state
Current_State = GPIO.input(GPIO_PIR)
if Current_State==1 and Previous_State==0:
# PIR is triggered
print " Motion detected!"
# Record previous state
GPIO.output(27,GPIO.HIGH)
sleep(1)
GPIO.output(27,GPIO.LOW)
Previous_State=1
elif Current_State==0 and Previous_State==1:
# PIR has returned to ready state
print " Ready"
Previous_State=0
# Wait for 10 milliseconds
sleep(0.01)

# clean up gpio pins when we exit the script
except KeyboardInterrupt:
print " Quit"
# Reset GPIO settings
GPIO.cleanup()