A method of servicing a wellbore extending from a surface and penetrating a subterranean formation is provided. The method comprises placing a assembly in the wellbore, wherein the assembly comprises at least a first downhole tool, a signal receiver subassembly, and a conveyance between the first downhole tool and the surface. The method further comprises the signal receiver subassembly receiving a first signal generated by contact between the wellbore and the assembly and initiating a first function of the first downhole tool based on the first signal.