How to trace the copies of your knowledge ...

If you do a google search for "disbale timer2 while" (yes: disbale!!!) you get 95 hits (at the time of writing). Some of them:

  1. Arduino Blag: Timer2 and Overflow Interrupt: Let's Get Cooking
  2. electric-xmas/MusicControl.ino at master · interactive-matter ... - GitHub
  3. MotorController.ino - GitHub
  4. How to read TTL sensor every exact time interval? - Arduino Forum
  5. a lot of work commited; - Gitorious
  6. Como criar um delay dentro de uma int do timer2 - Laboratorio de ...
  7. ZONADEPRUEBAS • Ver Tema - żAlguien se aclara con Arduino y C?
  8. [C#] #include #include "DHT.h ... -
$64 question: which one was the original?

Was the mistake inserted intensionally to trace plagiarism?

You want another nice example?

When writing the examples for the Arduino Ethernet library (very good ones, indeed), one of these authors David A. Mellis, Tom Igoe, or Adrian McEwen was a little bit too fast hitting his keyboard, mistyping a   k   for an   i  .
So do a search for the string

kf you didn't get a connection to the server.

And don't be surprised to find some 48,300 hits.

Among them you even find books like Making Things Talk (O'Reilly, 2nd Edition)
Using Sensors, Networks, and Arduino to see, hear, and feel your world By Tom Igoe.

Or another one:

Look for "define the cymbols" and you get 128.000 hits. What exactly is a cymbol?

contact: nji(at)