Controlling the Influence of PCI DMA Transfers on Worst Case Execution Times of Real–Time Software
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چکیده
The PCI Local Bus is used in all general purpose computer systems. Peripheral devices connected to this bus may perform transactions autonomously. If a processor accesses the main memory or performs an I/O instruction, the execution time of these operations depends on the working load of the PCI bus and of the communication protocols being used by the chip set. In this paper the influence of the PCI Local Bus on real– time software is demonstrated. A method is presented reducing these impacts of the PCI Local Bus on the execution time of real–time software. Thus accesses to PCI peripherals from real–time tasks behave more deterministically.
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تاریخ انتشار 2004