Disambiguating intentional and incidental contact and motion in multi-touch pointing devices

An input device has both a touch sensor and a position sensor. A computer using data from the input device uses the relative motion of a contact on a touch sensor with respect to motion from a position detector to disambiguate intentional from incidental motion. The input device provides synchronized position sensor and touch sensor data to the computer to permit processing the relative motion and performing other computations on both position sensor and touch sensor data. The input device can encode the magnitude and direction of motion of the position sensor and combines it with the touch sensor data from the same time frame, and output the synchronized data to the computer.