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:
May. 30, 1995
Filed:
Apr. 20, 1993
Stephen C Kromer, Austin, TX (US);
Advanced Micro Devices, Inc., Sunnyvale, CA (US);
Abstract
The invention facilitates testing of electrical circuitry which includes a circuit receiving a signal asynchronous with respect to the circuit clock. The exact clock pulse on which the asynchronous signal is asserted may be difficult or impossible to predict even when the circuitry inputs are known. However, a range of pulses can be determined during which the asynchronous signal is asserted. The sampling of the asynchronous signal is blocked until the end of the range of pulses. If it is known that at the end of the range of pulses the asynchronous signal should still be asserted provided that the circuitry functions properly, the asynchronous signal is sampled at the end of the range of pulses. Alternatively, if the asynchronous signal can be deasserted by the end of the range of pulses, the assertion of the asynchronous signal is detected and latched by the asynchronous signal pulse detector, and at the end of the range of pulses the circuit samples the value latched by the pulse detector. In both alternatives, the end of the range of pulses facilitates an unabiguous clock pulse at which the asynchronous signal should be sampled.