Gerald Mark Garcia

55068758, Apr 9, 1996

Dec 13, 1993

8/165686

Charles E. Nuckolls - Austin TX
James R. Lundberg - Austin TX
Gerald W. Garcia - Austin TX

Motorola, Inc. - Schaumburg IL

H03D 324

375375

A method and apparatus for performing frequency acquisition. Frequency acquisition is accomplished by utilizing binary-search techniques with a controller (13), variable digital oscillator (16), frequency detector (11) an incrementor (19) and decrementor (21) and control registers (22). The frequency detector (11) generates an output indicating the relative speed of the variable oscillator (16) with reference to a externally provided signal. Depending on the output of the frequency detector (11 ), the arithmetic logic circuitry (19, 21) will increase or decrease the value in a control register (22), resulting in a corresponding increase or decrease in speed of the variable oscillator (16). The magnitude of changes to the control register (22) is gradually reduced as the steps of frequency detection and arithmetic updates are repeated until the variable oscillator (16) has reached the proper frequency.