An electronic storage system includes a substrate with a state region, a transceiver with memory and a controller, and a code circuit disposed over the substrate separate from the transceiver and electrically connected thereto. The code circuit includes a conductor whose electrical or mechanical state can be externally altered. At intervals, the transceiver electrically excites the code circuit and detects the electrical state of an input pad connected to the code circuit. The electrical state corresponds to the excitation and to the electrical or mechanical state of the conductor. The controller stores the detected state or a representation thereof in the memory. In response to a downlink signal, the transceiver transmits an uplink signal representing the stored detected electrical state(s) of the input pad, or the stored representations thereof.