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:
Nov. 14, 1989
Paul H Sharp, Aloha, OR (US);
Roland Corporation, Osaka, JP;
Abstract
A mathematical function-generating device for producing, in an electronic musical instrument, functional values from an accumulation of first digital data. A digital data-generating circuit generates first digital data. A digital value string-generating circuit generates a bit-reversed digital value which increments a predetermined amount each time a first digital data unit is generated and which corresponds to a predetermined number of least significant bits in said first digital data unit. An adder is provided for adding the first digital data to a digital value comprising an accumulated value truncated to a predetermined number of least significant bits and having the bit reversed digital data concatenated thereto, thereby producing a new accumulated value. A memory is provided for storing and truncating each new accumulated value. The memory also supplies the adder with the new accumulated value. The first digital data corresponds to gradients of a linear or exponential curve and may be used as address signals to read waveform data from a memory. The accumulated values give functional values of that curve, which may represent an envelope waveform.