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:
Mar. 17, 1998
Filed:
Dec. 24, 1996
Tadhg Creedon, County Galway, IE;
Richard A Gahan, County Galway, IE;
Fearghal Morgan, County Galway, IE;
Digital Equipment Corporation, Maynard, MA (US);
Abstract
Arbitration means for arbitrating between computer devices A to F which compete for access to a common bus. The system provides cascaded round-robin units. Unit RR1 has ports A, B, C, and X in sequence, with port X coupled to round-robin unit RR2, which has ports D, E, F in sequence. On each cycling of unit RR1 past C to A, unit RR2 is checked and the next one of devices D to F (in the sequence determined by unit RR2) has the opportunity of bus access. A gating circuit 13 can further restrict bus accessing by unit RR2's devices, by timing or counter control. A third round-robin unit can be added coupled to unit RR1 (which would have ports A, B, C, X,Y) or to unit RR2 (which would have ports D, E, F, Y). The assignment of devices to ports can be controllable by a matrix switch and device assignment memory.