[54] ADAPTIVE PRIORITY DETERMINATION
FOR SERVICING TRANSMIT AND RECEIVE
IN NETWORK CONTROLLERS
[75] Inventors: Shashank C. Merchant, Sunnyvale;
Jeffrey Roy Dwork, San Jose, both of
Calif.
[73] Assignee: Advanced Micro Devices, Inc.,
Sunnyvale, Calif.
[21] Appl. No.: 08/782,271 [22] Filed: Jan. 13, 1997
[51] Int. CI. H04L 12/54
[52] U.S. CI 370/234; 370/413
[58] Field of Search 370/229, 230,
370/231, 232, 233, 234, 235, 236, 412, 413, 414, 415, 416, 417, 418; 395/200.5, 200.56, 200.62, 200.63, 200.64, 200.65, 200.7, 200.8, 200.83, 200.43, 872, 873,
876, 877
[56] References Cited
U.S. PATENT DOCUMENTS
4,839,891 6/1989 Kobayashi et al 370/231
4,942,553 7/1990 Dalrymple et al 395/877
5,136,582 8/1992 Firoozmand 370/400
5,210,749 5/1993 Firoozmand 370/463
5,293,487 3/1994 Russo et al 395/200.8
5,440,691 8/1995 Carrafiello et al 395/200.64
5,682,552 10/1997 Kuboki et al 395/872
OTHER PUBLICATIONS
AMD, AM79C971 PCnetTM-FAST Single-Chip Full-Duplex 10/100 Mbps Ethernet Controller for PCI Local Bus, May 1996.
Primary Examiner—Chi H. Pham
Assistant Examiner—Kwang B. Yao
[57] ABSTRACT
A network interface stores data frames between a host computer and a network in a buffer memory. The network interface stores data frames received from the host computer via a peripheral component interconnect (PCI) bus in a transmit buffer for transmission on the network. The network interface also stores data from the network in a receive buffer for transfer to a host computer memory via the PCI bus. A priority control selectively allocates host computer resources based on network transmission and network reception by the network interface, and based on available space in the receive buffer, available data in the transmit buffer, and the estimated length of data packets received from the network. The selective allocation of host computer resources minimizes transmit buffer underflow and receive buffer overflow.
16 Claims, 8 Drawing Sheets
