Scaleable priority arbiter for arbitrating between multiple FIFO entry points of a network interface card
US6667983B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 27, 1999 |
| Grant date | Dec 23, 2003 |
| Priority date | — |
| Expiry date | May 27, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L49/90
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A scaleable priority arbiter for arbitrating between multiple FIFO entry points of a network interface card (NIC). The circuit provides a separate FIFO entry point circuit within the NIC for each data packet priority type. Exemplary priority types, from highest to lowest, include isochronous, priority 1, priority 2, . . . , priority n. A separate set of FIFO entry points are provided for NIC transmitting (Tx) and for NIC receiving (Rx). For each of the Tx FIFO entry points, a single Tx entry point register is seen by the processor and multiple downlist pointers are also maintained. The Tx entry point registers all feed a scaleable priority arbiter which selects the next message for transmission. The scaleable priority arbiter is made of scaleable circuit units that contain a sequential element controlling a multiplexer. The multiplexer selects between two inputs, a first input is dedicated to data packets of the priority type corresponding to the circuit stage and the other input comes from the lower priority chain. In one embodiment, timers regulate the transmission of isochronous packets. The arbiter transmits the isochronous packet, if any, with the timer and otherwise allows th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.