International Business Machines Corporation

Patrick K Kam

Robert J Devins

Emory D Keller

Stephen Yik-fai Hon

Gordon Taylor Davis

Fritz R Gfeller

Mahmoud Naghshineh

Claus Michael Olsen

Parviz Kermani

Peter Dirk Hortensius

John V Taglione

Danny N McKay

Babak Rezvani

James L Patrick, Jr

John Michael Krause

The invention provides a data processing system comprising: a CPU; a system memory; a plurality of network interfaces; a CPU bus connected to the system memory and to each of the network interface for initialization and control of the network interfaces by the CPU; an individual DMA bus connected to each of corresponding network interfaces and to the system memory; each of the network interfaces is connectable to an external network, whereby data can be transferred by the data processing system from one network to another using system memory.

Method and apparatus for moving data packets between networks while

In a wireless multi-rate communications system, a method for extending the range of communications in the system by dividing the physical layer frame into two portions: a robust header portion and a body, where the repetition rate of the data symbols in the header portion is greater than or equal to the repetition rate of the data symbols in the body of the frame. In this way the header can be received and decoded by all stations in the system with a high probability, while the body of the frame need only be received and decoded by the destination station to which the body of the frame is intended to be received and decoded.

Media access control protocols in a wireless communication network

A method and system are disclosed for simulating a direct memory access (DMA) function to access memory in a host computer having a DMA controller for the purpose of enabling the transfer of data between the host memory and a computer accessory data handling device not capable of DMA operation. The accessory data handling device can be operably connected to the host. The address contents of the DMA controller can be read to determine the location in the host memory where data is to be transferred from the host memory to the accessory data handling device or from the accessory data handling device to the host memory. Data is read from the host memory at the address specified in the DMA controller and written to the accessory data handling device or read from the accessory data handling device and written to the host memory at the address specified by the DMA controller, respectively. The host computer is informed that a DMA operation corresponding to the data transfer has been completed when the data transfer required has been completed.

DMA emulation for non-DMA capable interface cards

An audio system is provided for generating audio sound for a host computer. It includes an interface connector for connection with the host computer; an interface controller for communicating with the host computer using the interface connector; a trap adapted to trap audio instruction signals from an application running on the host, such as a game having an audio portion; a trap controller adapted to control the trap; and an audio output. The system operates with an interface communicator which is adapted to respond to a request from the interface controller to read information from the trap and send audio output instruction to the audio output to generate audio sound.

Audio adapter card and method for trapping audio command and producing

Apparatus and method for providing virtual DMA capability for an adapter card connected to a host system bus with no DMA support. A special interface circuit resides on an adapter card together with a cache data memory. A special software driver resides in the host system. The software driver manages DMA transfers for the application processing circuitry on the adapter card using the cache data memory. The processing circuitry on the adapter card transfers data in and out of the cache data memory as if it had direct memory access to host system memory. In this way, an adapter card for a non-DMA-capable bus, such as the personal computer memory card international association (PCMCIA) bus can act as a bus master.

Method and apparatus for providing virtual DMA capability on an adapter

Growing community of inventors

Pickering, Canada

Patrick K Kam