Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
Computer system having a bridge between two buses with a direct memory access controller and an alternative memory access controller










Image Number 3 for United States Patent #5621902.

A computer system having a peripheral controller interconnect (PCI) bus and an industry standard architecture (ISA), with ISA compatible devices coupled to the ISA bus, is provided with a first bridge coupled between the PCI and ISA buses. The first bridge has a first direct memory access (DMA) control circuit for controlling DMA transfers with the ISA devices. In order to achieve expanded compatibility with other types of devices, the system is also provided with an expansion bus, such as a Microchannel bus, with Microchannel compatible devices coupled to the Microchannel bus. A second bridge is coupled between the PCI and the Microchannel buses. This second bridge has a second DMA control circuit that controls DMA transfers with the ISA devices and with the Microchannel devices. Software disables the first DMA control circuit such that only the second DMA control circuit controls DMA transfers within the computer system.








 
 
  Recently Added Patents
Fan guide
Fine grain voltage scaling of back biasing
Composition comprising a mixture of dextro- and levo-amphetamines complexed with ion-exchange resin particles to form drug resin particles
Reliable event broadcaster with multiplexing and bandwidth control functions
Clamp for fence panels
Methods of isolating bipotent hepatic progenitor cells
Apparatus and method for sterilizing vessel with electron beam
  Randomly Featured Patents
Axial air gap motor
Nutritional supplement for diabetics
Forming device for bevelling
Supporting foot
Structural member
Absorbents
Remote access apparatus and method which allow dynamic internet protocol (IP) address management
Bilge pump activator switch
Copper interconnect with metal hardmask removal
One-piece two-way mailer unit