Disk drive controller
CA 1318412 C · Owner: Apple Computer, Inc. · Inventors: Sandor, Brian; Sandor, Wendell
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invented controller uses a programmable parameter scheme which makes it possible to read and write 3 1/2 inch variable and fixed speed drives, as well as standard 5 1/4 inch drives. Additionally the present invention uses a plus/minus rate multiplier to correct for symmetry and frequency errors. Also provided is a form of read post compensation which corrects for peak shift effects on disks with insufficient precompensation. Other advanced features of the present invention include the use of half clock circuits to provide half clock resolution in the signal being written to and read from the disk and the capability of operating at continuously variable clock speeds and data rates …
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Granted May 25, 1993. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 25, 2010.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.