Lecture Operating System: Chapter 05 - Input/Output presented Principles of I/O hardware, Principles of I/O software, I/O software layers, Disks, Clocks, Character-oriented terminals, Graphical user interfaces, Network terminals, Power management. | Input/Output Chapter 5 Principles of I/O hardware Principles of I/O software I/O software layers Disks Clocks Character-oriented terminals Graphical user interfaces Network terminals Power management Principles of I/O Hardware Some typical device, network, and data base rates Device Controllers I/O devices have components: mechanical component electronic component The electronic component is the device controller may be able to handle multiple devices Controller's tasks convert serial bit stream to block of bytes perform error correction as necessary make available to main memory Memory-Mapped I/O (1) Separate I/O and memory space Memory-mapped I/O Hybrid Memory-Mapped I/O (2) (a) A single-bus architecture (b) A dual-bus memory architecture Direct Memory Access (DMA) Operation of a DMA transfer Interrupts Revisited How interrupts happens. Connections between devices and interrupt controller actually use interrupt lines on the | Input/Output Chapter 5 Principles of I/O hardware Principles of I/O software I/O software layers Disks Clocks Character-oriented terminals Graphical user interfaces Network terminals Power management Principles of I/O Hardware Some typical device, network, and data base rates Device Controllers I/O devices have components: mechanical component electronic component The electronic component is the device controller may be able to handle multiple devices Controller's tasks convert serial bit stream to block of bytes perform error correction as necessary make available to main memory Memory-Mapped I/O (1) Separate I/O and memory space Memory-mapped I/O Hybrid Memory-Mapped I/O (2) (a) A single-bus architecture (b) A dual-bus memory architecture Direct Memory Access (DMA) Operation of a DMA transfer Interrupts Revisited How interrupts happens. Connections between devices and interrupt controller actually use interrupt lines on the bus rather than dedicated wires Principles of I/O Software Goals of I/O Software (1) Device independence programs can access any I/O device without specifying device in advance (floppy, hard drive, or CD-ROM) Uniform naming name of a file or device a string or an integer not depending on which machine Error handling handle as close to the hardware as possible Goals of I/O Software (2) Synchronous vs. asynchronous transfers blocked transfers vs. interrupt-driven Buffering data coming off a device cannot be stored in final destination Sharable vs. dedicated devices disks are sharable tape drives would not be Programmed I/O (1) Steps in printing a string Programmed I/O (2) Writing a string to the printer using programmed I/O Interrupt-Driven I/O Writing a string to the printer using interrupt-driven I/O Code executed when print system call is made Interrupt service procedure I/O Using DMA Printing a string using DMA code executed when the print system call is made
