If you want an article on general 74hc595 shift register usage with detailed explanition on how it works/what it’s doing, you want this article here: http://bildr.org/2011/02/74hc595/ The following code and library are compatible with arduino software 1.0+ ONLY. You can download the newest version of the arduino software here. Earlier this year we did an article on using the 74hc595 shift register with your ...