Button-handling via callback

button_led.py

@@ -4,23 +4,27 @@ from time import sleep
 
 import RPi.GPIO as GPIO
 
+ledPin = 14
+buttonPin = 16
+
+def buttonHandler(channel):
+    print "button pushed"
+    GPIO.output(ledPin, not GPIO.input(ledPin))
+
 try:
     GPIO.setmode(GPIO.BCM)
-    GPIO.setup(4, GPIO.OUT)
+    GPIO.setup(ledPin, GPIO.OUT)
-    GPIO.setup(14, GPIO.IN, pull_up_down=GPIO.PUD_UP)
+    GPIO.setup(buttonPin, GPIO.IN, pull_up_down=GPIO.PUD_UP)
+    GPIO.setup(15, GPIO.IN, pull_up_down=GPIO.PUD_UP)
 
-    last_state = True
+    GPIO.add_event_detect(buttonPin, GPIO.FALLING, callback=buttonHandler, bouncetime=300)
-    last_led_state = False
+
+    GPIO.output(ledPin, False)
     
     while True:
-        input_state = GPIO.input(14)
+        GPIO.wait_for_edge(15, GPIO.RISING)
-        if input_state == False and input_state != last_state:
+        print "blah"
-            print 'Button pressed'
-            GPIO.output(4, ~last_led_state)
-            last_led_state = ~last_led_state
-        last_state = input_state
-        sleep(0.1)
 except KeyboardInterrupt:
-    GPIO.output(4, False)
+    GPIO.output(ledPin, False)
 finally:
     GPIO.cleanup()

led.py

@@ -6,17 +6,19 @@ import RPi.GPIO as GPIO
 
 print 'blah'
 
+pin = 14
+
 try:
     GPIO.setmode(GPIO.BCM)
-    GPIO.setup(4, GPIO.OUT)
+    GPIO.setup(pin, GPIO.OUT)
 
     while True:
-        GPIO.output(4, 1)
+        GPIO.output(pin, 1)
         sleep(1)
-        GPIO.output(4, 0)
+        GPIO.output(pin, 0)
         sleep(1)
 except KeyboardInterrupt:
-    GPIO.output(4, 0)
+    GPIO.output(pin, 0)
 finally:
     GPIO.cleanup()