Transparent direct memory access

Details Transparent direct memory access Transparent direct memory access

1998-05-06

2000-10-24

Auve, Glenn A.

Electrical computers and digital data processing systems: input/

Input/output data processing

Direct memory accessing

710129, 703 23, G06F 1314

Patent

active

061381837

ABSTRACT:
A transparent direct memory access method comprises emulating an ISA-bus mapped direct memory access controller (ISA-DMAC) with a PCI-bus mapped direct memory access controller (PCI-DMAC). The ISA-DMAC exists, but there may not actually be any resources mapped into the ISA-bus space. Write snooping by the PCI-DMAC of a PCI-bus processor detects whenever an attempt is made to write the ISA-DMAC, and copies the data written into the ISA-DMAC registers into a corresponding register of the PCI-DMAC. The direct memory access operation commanded by the PCI-bus processor of the ISA-DMAC is performed by the PCI-DMAC in the PCI-bus resource space. When the direct memory access operation is completed, the PCI-DMAC updates its registers and does a write back to update the ISA-DMAC registers. The PCI-bus processor can then read the PCI-DMAC directly for status, or if legacy software is running the ISA-DMAC will respond with the appropriate register value.

REFERENCES:
patent: 5506997 (1996-04-01), Maguire et al.
patent: 5619703 (1997-04-01), Omid et al.
patent: 5621902 (1997-04-01), Cases et al.
patent: 5664197 (1997-09-01), Kardach et al.
patent: 5673400 (1997-09-01), Kenny
patent: 5678064 (1997-10-01), Kulik et al.
patent: 5729762 (1998-03-01), Kardach et al.
patent: 5740452 (1998-04-01), Story et al.
patent: 5745772 (1998-04-01), Klein
patent: 5752043 (1998-05-01), Suzuki
patent: 5765024 (1998-06-01), Riley
patent: 5778242 (1998-07-01), Wang
patent: 5805842 (1998-09-01), Nagaraj et al.
patent: 5848278 (1998-12-01), Sakai
Implementing Legacy Audio On The PCI Bus, by Gary Solomon, Intel Corporation 1997.

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