Floppy disk controller with dma verify operations
CA 2028378 A1 · Owner: Culley, Paul R. · Inventors: Culley, Paul R.; Waldrop, Timothy K.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention includes two variations of an apparatus which generate a version of the IORC* bus signal that is supplied to the read strobe input of a floppy disk controller that is asserted at the appropriate time during verify cycles between the floppy disk controller and a DMA controller. These designs allow an 82077 floppy disk controller to operate properly in FIFO mode when it is being used with software that does not require generation of this signal. The designs include use of a PAL and certain bus signal inputs to generate a signal which is asserted at the appropriate times during verify transfers. This signal is combined with the regular IORC* bus signal to produce the …
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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 October 23, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 23, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 23, 2012.
- 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.