Shared direct memory access controller
CA 1089946 A · Owner: Sperry Rand Corporation · Inventors: Derchak, Nicholas
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A microprocessor system includes a microprocessor a, memory, and one or more direct memory access controllers all, connected to a common system bus which includes a system address bus and a system data bus. At least one of the direct memory access controllers is shared by a plurality of subsystem device controllers which may control peripheral devices having diverse characteristics. The microprocessor is limited in its instruction repertoire and may control peripheral devices only by means of an input and an output instruction. The shared direct memory access controller includes no circuitry which is specifically for controlling only a single type of peripheral device, the device dependent …
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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 November 18, 1980. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended November 18, 1997.
- 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.