Interfacing Processors and Peripherals

Publisher Summary This chapter provides an overview of interfacing processors and peripherals. Many of the characteristics of input/output (I/O) systems are driven by technology in processors, for example, the properties of disk drives affect how the disks should be connected to the processor and how the operating system interacts with the disks. I/O systems, however, differ from processors in several important ways. Although processor designers often focus primarily on performance, designers of I/O systems must consider issues such as expandability and resilience in the face of failure as much as they consider performance. Performance in an I/O system is a more complex measurement than for a processor. Performance depends on many aspects of the system such as the device characteristics, the connection between the device and the rest of the system, the memory hierarchy, and the operating system. The chapter explores the structure of a system with its I/O. All the components from the individual I/O devices to the processor to the system software will affect the performance of tasks that include I/O. The chapter also discusses I/O performance measures, presenting some examples from disk and file systems, types and characteristics of I/O devices, and interfacing I/O devices to the memory, processor, and operating system.