Method for determining rotational data using an encoder device

A method for determining rotational data from a random pulse pair generated by an encoder device, the encoder device being used to monitor the rotation of a rotating member, comprising the steps of:

• receiving a plurality of pulses from said encoder device, such that each of said plurality of pulses being indicative of a rotational distance that has been traveled by said rotating member;
• storing a time value for each of said plurality of pulses that has occurred during the two most recent revolutions of the rotating member;
• identifying a first pulse and a second pulse, said first and second pulse having occurred in the most recent revolution of the rotating member;
• retrieving a first time value for the first pulse corresponding to when the first pulse occurred during the most recent revolution of the rotating member;
• retrieving a second time value for the second pulse corresponding to when the second pulse occurred during the second most recent revolution of the rotating member;
• and
• computing a time difference between said first pulse and said second pulse by subtracting the second time value from the first time value;
• and
• using said time difference to determine a rotational speed for the rotating member, thereby determining rotational data from the random pulse pair.