DMA ACCESS ARBITRATION DEVICE IN WHICH CPU CAN ARBITRATE ON BEHALFOF ATTACHMENT HAVING NO ARBITER

摘要

IBM Docket No. BC9-87-001DMA ACCESS ARBITRATION DEVICE IN WHICH CPU CANARBITRATE ON BEHALF OF ATTACHMENT HAVING NO ARBITERABSTRACT OF THE DISCLOSUREIn a computer system having both peripherals havingtheir own DMA channel arbiter and peripherals having noarbiter, a separate arbitration unit, controlleddirectly by the CPU, is provided to arbitrate on behalfof peripherals having no arbiter. The CPU can thusfreely assign different arbitration levels to suchperipherals, and can instruct the arbitration unit tosimultaneously arbitrate on different arbitrationlevels or for two or more DMA channels.