Touch surface scanning method and device

A device acquires first sense data representing first electrical signals sensed from a first subset of a plurality of sensors of a touch surface. The device acquires second sense data representing second electrical signals sensed from a second subset of the plurality of sensors. The device detects a first set of one or more touches based on the first sense data and the second sense data. After the acquiring of the first sense data, the device acquires third sense data representing third electrical signals sensed from the first subset of the plurality of sensors; and detects a second set of one or more touches at the touch surface based on the second sense data and the third sense data.