Method and apparatus for processing programmed input/output (PIO) operations in a computer system

摘要

A method and apparatus are provided for processing programmed input/output (PIO) operations in a computer system. A batched list of PIO operations is stored in a buffer. Then the batched list of PIO operations is moved as a single system bus operation to an I/O bus interface unit. The I/O bus interface unit includes sequencer logic. The sequencer logic is used for executing the batched list of PIO operations and for providing an ordered sequence of PIO operations to a system I/O bus. The method and apparatus of the invention enhances the use of non-intelligent I/O adapters in a computer system by reducing the overhead of system PIO operations. Also the correctly ordered sequence of PIO commands provided by the sequencer logic facilitates the use of non-intelligent I/O adapters in reduced instruction-set computer (RISC) systems.