A mobile device includes a conductive element and a ground node. The conductive element is configured to be detected by a proximity sensor. A switch is coupled between the conductive element and ground node. The conductive element is coupled to the ground node by closing the switch. A first memory element is configured to control the switch. The first memory element includes a register bit coupled to a control terminal of the switch. A data output is configured to control the switch. A FIFO is configured to provide data to the data output. The first memory element includes a FIFO. A capacitive touch controller is configured to measure a capacitance of the conductive element. A digital processing unit is configured to convert the capacitance of the conductive element to a bit of data. A second memory element is configured to store the bit of data.