From 517877559d7f334cbc6694767dd71585f425f677 Mon Sep 17 00:00:00 2001
From: Michael Mandl <mandlm@molez.net>
Date: Thu, 31 Dec 2015 14:11:37 +0100
Subject: [PATCH] Button-handling via callback

---
 button_led.py | 28 ++++++++++++++++------------
 led.py        | 10 ++++++----
 2 files changed, 22 insertions(+), 16 deletions(-)

diff --git a/button_led.py b/button_led.py
index 3093c68..c634b6c 100755
--- a/button_led.py
+++ b/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(14, GPIO.IN, pull_up_down=GPIO.PUD_UP)
+    GPIO.setup(ledPin, GPIO.OUT)
+    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
-    last_led_state = False
+    GPIO.add_event_detect(buttonPin, GPIO.FALLING, callback=buttonHandler, bouncetime=300)
 
+    GPIO.output(ledPin, False)
+    
     while True:
-        input_state = GPIO.input(14)
-        if input_state == False and input_state != last_state:
-            print 'Button pressed'
-            GPIO.output(4, ~last_led_state)
-            last_led_state = ~last_led_state
-        last_state = input_state
-        sleep(0.1)
+        GPIO.wait_for_edge(15, GPIO.RISING)
+        print "blah"
 except KeyboardInterrupt:
-    GPIO.output(4, False)
+    GPIO.output(ledPin, False)
 finally:
     GPIO.cleanup()
diff --git a/led.py b/led.py
index 5aa4052..94b7d31 100755
--- a/led.py
+++ b/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()