====== Node identification====== 

  * Each node has a unique id so user can refer to it during configuration
    * based on the ratio of two resistors
    * dip switch
      * convert 8 switch position into a number from 0 to 256
      * communicate number to AtMega (one wire bus)
    * **Flash chip has a 4 bytes unique identifier**
  * <del>Each node uses the same code binaries so it need to be configurable</del>
    * Not sure moteino's have enough memory for that
    * Increase complexity