A surgical tool system with a powered tool (30) that includes a memory (90) in which data describing the characteristics of the power signals that are to be sourced to the toll are stored. A control console (40) based on the data in the tool memory sources the power signal to the tool. Both the data signals written out from the tool memory and the power signals from the console are exchanged over common console terminals (56, 58) and common tool terminals (82, 84) an isolation circuit (94, 98, 102) in the tool prevents the applied power signals from the console from adversely effecting the tool memory.
