A downhole drilling assembly may comprise a sub secured between a drill string and a drill bit. The sub may comprise a cavity with a chassis housed therein. The drill bit may also comprise a cavity with an extender housed therein. This extender may provide access for various types of communication to reach into the drill bit's cavity. Several pairs of interfacing exchange surfaces may allow for communication (e.g. passing electrical, hydraulic, optical or electromagnetic signals) between these various elements. One pair of interfacing exchange surfaces, between the drill string and the chassis, may allow for communication regardless of relative rotational orientation. Two other pairs of interfacing exchange surfaces, one between the chassis and the extender and another between the extender and the drill bit, may require a specific rotational orientation for communication.