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:
Apr. 30, 1985
Filed:
Apr. 02, 1982
Kenneth Louth, Los Altos, CA (US);
Ampex Corporation, Redwood City, CA (US);
Abstract
An improved microprocessor controlled scanning drum servo adapted for use in a recording and reproducing apparatus is disclosed. The scanner servo includes a velocity loop as well as a position loop, and by virtue of the fact that it is controlled by a microprocessor in a unique way, has extraordinary accuracy because the resolving power of the servo is essentially that of the microprocessor itself. The interrupts to the microprocessor occur in sequence with a first interrupt causing the microprocessor to cease current activity, store all required information in a stack register and thereafter wait until a subsequent interrupt occurs which enables it to immediately act to perform control operations with respect to the scanner servo. This enables the velocity loop to perform the vast majority of the work required by the servo and as a result of this, the phase closed servo loop operates as a positioning loop in the true sense.