Systems and methods receive multiple of trigger signals and responsive to each trigger signal transition a sensing block from operating in a first mode to operating in a second mode by turning on power to one or more portions of the sensing block. Operating in the second mode includes performing multiple sensor scans during multiple sensing periods of a monitoring period. Based on performing a first scan during a first sensing period, systems and methods transition from operating the sensing block in the second mode to operating the sensing block in the first mode by turning off the power to the one or more portions of the sensing block. Based on performing a second scan during a second sensing period, of the plurality of sensing periods, systems and methods transition a processing module from operating in a first processing mode to operating in a second processing mode.