A circuit comprises two or more chains of components, each chain
comprising a plurality of components serially connected by designated
pins on each component and at least one chain including one or more
components of another chain, the designated pins being designated for
data for one or more specific purposes. A selector is included for
selecting one chain from the two or more chains over which to data is to
be sent. Another circuit comprises a chain of components serially
connected by designated pins on each component, and two or more
controllers, each controller capable of controlling the chain for one or
more of the specific purposes. A wiring board for implementing the
circuit is also provided.