US5968153A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Mechanism for high bandwidth DMA transfers in a PCI environment
Assignee: Hewlett Packard Enterprise Development LP
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Filing: 1998-10-13
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Granted: 1999-10-19
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Expires: 2018-10-13
Abstract
Abstract A method and apparatus for maximizing the performance of DMA transfers over a PCI™ bus are provided which includes a Per-Channel Retry count, Double Buffer Management, Wait Enable functionality, Back Up register functionality, Gather/Scatter mapping, a method for minimization of PIO writes, Read Semaphore functionality, a method for servicing of DMA transfers during FMU latency periods, Valid bit functionality, high and low water thresholds, and re-usable page tables.
Inventors
- 👤 William R. Wheeler
- 👤 Matthew James Adiletta
- 👤 Samuel Ho
- 👤 Debra Bernstein
- 👤 Gilbert M. Wolrich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 08:55
CPC Classifications
G; G06; G06F; G06F13/00; G06F13/14; G06F13/20; G06F13/28
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
145 words
A method for transferring data over a data bus comprising the steps of: acquiring ownership of said data bus by a first device; initiating, by a first device coupled to said data bus, a plurality of data transfers between said first device and a second device; altering the length of each of said plurality of transfers responsive to a characteristic of said transfer; storing a plurality of time representation values in a plurality of storage elements, each of said time representation values relating to one of a plurality of types of data that can be transferred by said data transfers; and accessing of said time representation values by said first device upon interruption of one of said plurality of data transfers for determining a duration of time to wait before said first device requests resumption of said interrupted one of said plurality of data transfers.
Claim 2
Independent Claim
145 words
A method for transferring data over a data bus comprising the steps of: acquiring ownership of said data bus by a first device; initiating, by a first device coupled to said data bus, a plurality of data transfers between said first device and a second device; altering the length of each of said plurality of transfers responsive to a characteristic of said transfer; storing a plurality of time representation values in a plurality of storage elements, each of said time representation values relating to one of a plurality of types of data that can be transferred by said data transfers; and accessing of said time representation values by said first device upon interruption of one of said plurality of data transfers for determining a duration of time to wait before said first device requests resumption of said interrupted one of said plurality of data transfers.
Claim 3
Independent Claim
130 words
A method for transferring a plurality of data elements over a data bus comprising the steps of: acquiring ownership of said data bus by a first device; initiating, by a first device coupled to said data bus, a plurality of data transfers between said first device and a second device; altering the length of each of said plurality of transfers responsive to a characteristic of said transfer; storing said plurality of data elements in a first storage location; storing a copy of each of said plurality of data elements in a second storage location while each of said data elements are being transferred over said data bus; and reallocating said first storage location when second to last of said plurality of data elements if being transferred over said data bus.
Claim 4
Independent Claim
130 words
A method for transferring a plurality of data elements over a data bus comprising the steps of: acquiring ownership of said data bus by a first device; initiating, by a first device coupled to said data bus, a plurality of data transfers between said first device and a second device; altering the length of each of said plurality of transfers responsive to a characteristic of said transfer; storing said plurality of data elements in a first storage location; storing a copy of each of said plurality of data elements in a second storage location while each of said data elements are being transferred over said data bus; and reallocating said first storage location when second to last of said plurality of data elements if being transferred over said data bus.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-10-18 | 2003-04-19 | 2003-10-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-10-18 | 2007-04-19 | 2007-10-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-10-18 | 2011-04-19 | 2011-10-19 | $7700.00 | Window Closed / Lapsed |