Queue based arbitration using a FIFO data structure

摘要

A queue based arbiter to arbitrate between N devices of a computer system for access to a system bus which eliminates the need to maintain a history of bus transactions by queuing bus requests to track when a bus request is posted. The arbiter provides fair access to the bus by maintaining a queue of requests that come in from each resource in the computer system. This is accomplished by continually sampling the individual request lines of the devices to determine if a device is requesting access to the bus. Each time the arbiter detects a request from a device it puts an entry representative of the specific device that has requested the bus into a queue that has at least N entries. Requests are granted in the order that they are queued.