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. 03, 1989
Filed:
Apr. 22, 1983
Applicant:
Inventors:
Melvyn J Marple, Newtown, CT (US);
Andrew S Potemski, New Milford, CT (US);
Assignee:
International Business Machines Corporation, Armonk, NY (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G06F / ;
U.S. Cl.
CPC ...
364200 ; 3642481 ; 364265 ; 3642655 ; 3642706 ; 371-7 ; 371 61 ;
Abstract
A processor and disk controller are arranged to operate with either of two types of disk drive, a drive for a five and one-fourth inch disk or a drive for an eight inch disk, and a method and apparatus are provided to test a port to detect which type disk is connected. The disk drives do not directly signal their type, and in one operation this information is derived from 'drive ready', signals that are supplied separately by each disk type. In an alternative method and apparatus, this information is derived by a test in which the clock speed is changed.