From 6cf277c1fe9940d927da6bf0b19496eb8b6cb897 Mon Sep 17 00:00:00 2001
From: Admar Schoonen <admar@luon.net>
Date: Wed, 4 Jan 2012 23:13:05 +0100
Subject: [PATCH] Ignore first sample from ADC

ADC of AVR contains a 'bug' that causes first sample to be corrupt. Fixed in
code now.
---
 wordclock/wordclock.ino | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/wordclock/wordclock.ino b/wordclock/wordclock.ino
index 9572b45..b8d36a5 100644
--- a/wordclock/wordclock.ino
+++ b/wordclock/wordclock.ino
@@ -194,6 +194,9 @@ void setup()
   pinMode(LED4PIN, OUTPUT);
 
   analogReference(DEFAULT);
+  // known 'bug' in AVR ADC: after switching analog reference, first sample
+  // could be corrupt and should be ignored --> discard this sample now
+  analogRead(LIGHTSENSOR_INPUTPIN);
 
   current_brightnes=MAXBRIGHTNESS;