| 摘要 |
<p>A bus arbitration system (10) is capable of granting access to an expansion bus to devices following two-wire bus arbitration protocol or a three-wire bus arbitration protocol. The bus arbitration system (10) receives a plurality of bus request signals from a plurality of devices. Each bus request signal is made up of one or more coded pulses and has a predetermined priority. A priority encoder (148) receives the bus request signal and assigns a priority level to each bus request signal. An arbiter (78) determines and stores in memory which bus request signal has a highest priority and whether the device follows two-wire bus arbitration protocol or a three-wire bus arbitration protocol. The expansion bus R(31:0) grants access to the bus to the device having the highest priority once a previous device if any, has relinquished the bus. <IMAGE></p> |
