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:
Feb. 15, 2000
Filed:
Jul. 15, 1997
David John Craft, Austin, TX (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
An apparatus for improving I/O pin interfaces for serial data communications is disclosed. In accordance with a preferred embodiment of the present invention, an improved serial interface is provided, which comprises an oscillator input, a signal input, a counter, a register, and a data output. The counter is utilized to count the number of cycles of the oscillator input for which the signal input is asserted. The register is utilized to receive a value from the counter when the signal input is next de-asserted. The data output is at a first logical state when the signal input is asserted for fewer oscillation cycles than the value stored in the register and the data output is at a second logical state otherwise, such that only one I/O pin is required for serial communications.