Resources Contact Us Home
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
Method and system for Bluetooth low power link layer connection setup
Network fault detection
Monitoring device for monitoring a display device
Phase noise extraction apparatus and technique
Stable pharmaceutical composition and methods of using same
  Randomly Featured Patents
Process for the NO-removal from engine exhaust gases
Telecommunications patch
Process for the biocatalytic, correct chain folding of denatured recombinant fusion proteins
Flip chip on glass (FCOG) image sensor
Contaminant containment structure for ventilation systems
Ski pole mounted windscreen
Mounting apparatus for an electrical power distribution device
Toner, method for producing toner, and developer
Flat panel display utilizing leaky lightguides
Ultrasonic Doppler diagnostic device