Distributed priority arbitrating method and system in multi-point serial

Abstract

This invention presents the serial arbitration method and system for rapidly and accurately identifying a station with the highest priority when a plurality of stations with different transmission rates are simultaneously requesting the use of a bus in a multi-point communication network where a plurality of communication stations share a common serial bus. This invention intends to improve the bus throughput by not only avoiding the collision of signals in a common serial bus, but also removing the possibility of arbitration failures when a plurality of contending stations have different transmission rates. For this purpose, a plurality of contending stations transmit modulated unique identity address serially in a form of self-clocking pulse on the OR-type single channel bus when the arbitration start signal is detected in multi-point networks. The stations that have activated the bus are allowed to participate in the next contention until a station with the highest priority is determined and the others are excluded from the contention by themselves in an asynchronous manner. When the activation timings are exactly the same on the bus, a station with the highest priority is determined by bit-serial comparison.