Apparatus and method for interfacing a data processor and an io controller to a main memory
CA 2172976 C · Owner: Mann, Edward D. · Inventors: Mann, Edward D.; Olson, Stephen W.; Macdonald, James B.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Disclosed are methods and apparatus for interfacing a central processor (12) (CP) and a IO controller (30) (IOC) to a main memory (40). A CP and a IO write buffer each include a pair of memory input data registers located in a pair of Memory Data Unit (MDU) integrated circuits (38a, 38b), and also two memory address registers a previous memory address register, and an address comparator located in a Memory Address Unit (MAU) (36). These registers in conjunction with associated control logic are used to buffer CP and IO, write addresses and data to the main memory. If both address registers have a pending write the last loaded address register is checked for a match against the current write …
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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
- Filed March 24, 1994 and granted February 19, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 24, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 24, 2016.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.