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:
Aug. 17, 1999
Filed:
Jun. 27, 1997
Stephen J Sicola, Monument, CO (US);
Bruce Sardeson, Colorado Springs, CO (US);
Frank M Nemeth, Colorado Springs, CO (US);
Mike Hare, Colorado Springs, CO (US);
Brian Schow, Colorado Springs, CO (US);
Digital Equipment Corporation, Houston, TX (US);
Abstract
In a SCSI subsystem having mixed wide and narrow SCSI devices installed, a method and apparatus is provided for detecting a narrow SCSI device illegally installed at a slot assigned to a wide SCSI device. To detect the narrow SCSI device installed at an illegal location, high ID and low ID SCSI bus address pairs are set as test pairs for the SCSI subsystem. The low ID is the alias of the high ID if a narrow SCSI device is installed at the high ID slot. To detect a conflict with a controller ID, a non-responsive ID bus address corresponding to a slot known to be unused is called. A response to this call indicates a narrow SCSI device is installed at the high ID of the test pair and the narrow SCSI device at the high ID has configured to an alias bus address matching the controller ID. To detect a present conflict between SCSI devices, the low ID bus address in the test pair is called. A conflict in responses indicates a SCSI device is installed at the low ID and a narrow SCSI device is installed at the high ID of the test pair. To detect a future conflict between a narrow SCSI device at a high ID and a SCSI device installed in the future at an unused low ID, both the low ID and the high ID are called. No response to the high ID call in combination with a response to the low ID call indicates a narrow SCSI device is installed at the high ID and the narrow SCSI device would conflict in the future with a SCSI device subsequently installed at the unused low ID.