Image Number 6 for United States Patent #6385672.
The present invention provides a device which facilitates communications between a computer system and a data network by buffering data in transit between the computer system and the data network in a single buffer memory which can be flexibly partitioned into separate transmit and receive buffers. This flexible partitioning allows the relative sizes of the transmit and receive buffers to be optimized across a wide range of buses, data networks and network usage patterns. The transmit and receive buffers are structured as ring buffers within respectively allocated portions of the buffer memory. The buffer memory is controlled by a simple finite state machine controller, which is free from the performance impediments and higher cost associated with a microprocessor-based controller. The present invention also provides support for retransmission of packets that encounter transmission problems such as collisions during transmissions on the data network. The present invention additionally provides the ability to discard incomplete packets.