PPT-Devices and Interrupts CS 3220

Fall 2014 Hadi Esmaeilzadeh hadiccgatechedu Georgia Institute of Technology Some slides adopted from Prof Milos Prvulovic Better Devices Now SW KEY can be read Problem several instructions needed to detect change. Programmed I/O. Interrupt-Driven I/O. . Direct Memory Access. (DMA). I/O Processors. 10/09/2014. 1. Input/Output. Systems and Peripheral Devices (02-2). Interrupt-Driven I/O. Principle of Interrupt-Driven I/O. of the lecture. :. Chandana. :. 1. . Introduction. 2. Example . 3. Definition . 4. Vector table and . Maskable. /. nonmaskable. interrupts . ________________________________________________. Hao. :. Anurag Dwivedi. Let Us Revise. Micro-Controllers. A small . computer integrated . in . a single IC. Has I/O pins, . RAM and Memory. We Use . Atmega. 16. Software Used. CvAvr. : Editor and Compiler. Interrupt Descriptor Table. Slide #. 2. IDT specified as a segment using the IDTR register . Slide #. 3. Calling the IRQ handler. Interrupt Context. Exceptions. First 32 IRQ vectors in IDT. Correspond to events generated by the CPU. Tami Meredith, Ph.D.. CSCI 3431. Why?. Devices need CPU access. E.g., NIC has a full buffer it needs to empty. These device needs are often asynchronous and unrelated to the currently executing process. Input/Output. Kristian. . Naess. Qicai. . Guo. Roy Torres. Mark Bacchus. Yue. Kun. Alberto . Chestaro. External Devices. The three key elements to a computer are:. . Processor(CPU), memory, and I/O devices. I/O is:. Varied. Complex. Error prone. A bad place for the typical user to be wandering around. The operating system really needs to make I/O a lot friendlier. Important Elements of I/O Architecture. Interrupt Handling. David Ferry, Chris Gill. CSE 522S - Advanced Operating Systems. Washington University in St. Louis. St. Louis, MO 63130. 1. Why Interrupts?. Interrupts allow a currently executing process to be preempted. Fall 2009. Kipp Schoenwald. Stephen . Hunte. Joseph Storey. Outline. Interrupts . Vectors and Vector Table. Flow Chart. Applications. Example 1. Example 2. Thermistors. Theory. Applications. Opto-isolators. Interrupts. . Prof. Chung-Ta King. Department of Computer Science. National Tsing Hua University, Taiwan. Materials from . MSP430 Microcontroller Basics. , John H. Davies, Newnes, 2008. 1. From Clock to Timer to CPU. David Ferry, Chris Gill. CSE 422S - Operating Systems Organization. Washington University in St. Louis. St. Louis, MO 63130. 1. Why Interrupts?. Interrupts allow a currently executing process to be preempted. Opto. -isolators, . Triacs. , and Thermistors. Alex Buchanan. Aaron May. Peter Ngo. Reason for Interrupts. You might want a certain subroutine executed immediately after a request from an external device or from an internal program, providing certain conditions are met.. Introduction to Operating Systems CPSC/ECE 3220 Fall 2019 Lecture Notes OSPP Chapter 2 – Part B (adapted by Mark Smotherman from Tom Anderson’s slides on OSPP web site) Types of Alerts to Kernel disable interrupts // Must finish put on queue of threads waiting for lock set guard to 0 call switch enable interrupts else value BUSY guard 0 LockRelease Why disable interrupts N