AN ARBITER FOR ARBITRATING BUS USAGE REQUESTS SENT BY DEVICES IN A CENTRALIZED BUS SYSTEM

摘要

The present invention provides an arbiter and its arbitration method. The master devices in the bus system can be divided into primary master devices and secondary master devices. Said arbiter has first and second stage arbitration modules, wherein the second stage arbitration module can be used for arbitrating bus usage requests sent by secondary master devices, and the first stage arbitration module can be used for arbitrating the arbitrated result of the second stage arbitration module and bus usage requests sent by primary master devices together, so that it can set arbitrating opportunity against different bus usage requests so as to raise arbitration efficiency and bus usage efficiency. The arbiter also provides reverse arbitration ability, which can avoid the conflict among returning data based on improving the bus usage efficiency.