Aspects of the present disclosure are directed to facilitating communications to respective circuit nodes in a manner that may also be useful for mitigating undesirable signal attenuation. As may be implemented in accordance with one or more embodiments, switchable isolation circuits, presented by at least one transformer and switch, are utilized to isolate adjacent data processing nodes on a bus in which each data processing node includes logic circuitry and processes signal therein. For each of the switchable isolation circuits, switching circuitry operates to mitigate communication propagation over the differential bus between adjacent data processing nodes, by switching the switchable isolation circuit for providing isolation. This approach may be utilized, for example, to assign sequential identification to daisy-chained circuit nodes upon start-up or reset, for use in addressing each node directly for further communication therewith.