I'm a relatively new modeler and my focus is on 3-rail Marklin digital. I have modified a number of locos to digital and I run my layout with an Arduino computer board, CAN Bus shield (a peripheral board that connects to the Arduino), Marklin track box which converts CAN Bus messages to Track commands, and various software packages. It has been a journey of discovery by trial and error, mostly because Marklin documentation is limited and at times confusing. My next step is to try and implement a DCC protocol on Marklin, which in theory should work with the Arduino, a motor shield, and various open source software packages such as DCC++, JMRI, and Desktop Station. If there is interest, I'll post my findings and experiences as they unfold. Thanks to TrainBoard for this site and online community!