combined.py

#!/usr/bin/python
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#
# pir_1.py
# Detect movement using a PIR module
#
# Author : Matt Hawkins
# Date   : 21/01/2013

# Import required Python libraries
import RPi.GPIO as GPIO
import time

# Use BCM GPIO references
# instead of physical pin numbers
GPIO.setmode(GPIO.BCM)

# Define GPIO to use on Pi
GPIO_PIR = 7
GPIO_TRIGGER = 23
GPIO_ECHO    = 24

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

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

# Set pins as output and input
GPIO.setup(GPIO_TRIGGER,GPIO.OUT)  # Trigger
GPIO.setup(GPIO_ECHO,GPIO.IN)      # Echo

# Set trigger to False (Low)
GPIO.output(GPIO_TRIGGER, False)

Current_State  = 0
Previous_State = 0

# Allow module to settle
time.sleep(0.5)

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
      Previous_State=1
      # Send 10us pulse to trigger
      GPIO.output(GPIO_TRIGGER, True)
      time.sleep(0.00001)
      GPIO.output(GPIO_TRIGGER, False)
      start = time.time()

      while GPIO.input(GPIO_ECHO)==0:
        start = time.time()

      while GPIO.input(GPIO_ECHO)==1:
        stop = time.time()

      # Calculate pulse length
      elapsed = stop-start

      # Distance pulse travelled in that time is time
      # multiplied by the speed of sound (cm/s)
      distance = elapsed * 34300

      # That was the distance there and back so halve the value
      distance = distance / 2

      print "Distance : %.1f" % distance
    elif Current_State==0 and Previous_State==1:
      # PIR has returned to ready state
      print "  Ready"
      Previous_State=0
      
    # Wait for 10 milliseconds
    time.sleep(0.01)      
      
except KeyboardInterrupt:
  print "  Quit" 
  # Reset GPIO settings
  GPIO.cleanup()