A unit train (10) includes a base unit (12). Base unit (12) generates a clock signal and a bit signal. Base unit (12) also receives and interprets a data signal. Unit train (10) also includes a plurality of subunits (14) serially coupled in a certain order. Each subunit (14) receives the clock signal...http://www.google.com/patents/US5594925?utm_source=gb-gplus-sharePatent US5594925 - Method and apparatus determining order and identity of subunits by inputting bit signals during first clock period and reading configuration signals during second clock period
