As part of our ongoing research, we present BSAA - Bus Switching Activity Analyser - a CAD tool which reads switching activity from RTL simulation, extracting a list of the circuit's buses and associated switching activity metrics. The list is filtered and sorted according to user-specified criteria, producing reports and a set of graphical switching activity profiles of the circuit's most active buses. The tool identifies common profiles corresponding to typical address- and data bus traffic. As part of a CAD flow, BSAA enables rapid switching activity analysis and encoding design for switching minimisation on heavily-loaded cross-chip buses and IO pins.