IRDetector by john.plocher

This sketch is missing a short description

This project is for a model railroad IR detector, used to sense when a part of a train is at a specific point along the track. It uses a before/after check to determine whether or not there is a reflection with some immunity from ambient lighting or external IR sources. It started as an AT-Tiny project loosely based on [Rob Paisley's designs](http://home.cogeco.ca/~rpaisley4/PhotoDetectors.html) and [dustinandrews' instructable](http://www.instructables.com/id/Make-an-Attiny13-based-IR-proximity-sensor-for-2/step4/Wire-it-up/) It evolved from a discrete logic circuit into an AT-Tiny one into a quad detector based on an Arduino core for ease of programming and economy of scale - one '328 is cheaper than 4x tiny's or the original (somewhat expensive) remote control TV detectors. Use the provided code with [board designs 2.1 and 2.2](http://www.spcoast.com/wiki/index.php/IO4-IR-Detector) - it will not work on the AT-Tiny versions!