The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 22, 1991
Filed:
Mar. 13, 1991
Casimir Karczewski, Lake Villa, IL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
This invention provides an improved method for synchronizing a slave oscillator with a master oscillator. The slave includes two counters designated Reference and System, driven by its oscillator; the master includes a System Counter driven by its oscillator. The master sends a reset signal to the slave, simultaneously resetting its System Counter. Periodically, the master sends to the slave a synchronization signal, which signal is generated at predetermined intervals based upon the master's System Counter. Upon receipt of the reset signal, the slave resets its counters. Later, upon receipt of the synchronization pulse, the slave modifies the value of its System counter based upon the closest multiple of the expected count value for the synchronization signal interval. The Reference Counter is not synchronized and runs free. At each synchronization signal, the slave compares its System Counter and Reference Counter to compute an oscillator error thus: ##EQU1## The slave stores this value and, depending on its mode of operation, uses it warp its own oscillator.