We present a wireless cortical stimulator comprising a plurality of multi-channel micro-stimulators allowing flexible placement of electrodes. These devices perform stimulation, and allow measurement of voltage or stimulating current at any electrode. Power and bi-directional data are managed by an Interface Module. Decoding of the ASK modulated carrier uses a low-power digital technique. A data rate higher than I Mbps is obtained. With its configurable protocol, a 1000 electrodes system is feasible with the proposed approach. Experimental results from a reduced size prototype combining integrated Stimulating Modules and a discrete components Interface Module are shown.