Interrupt - driven input-output, Computer Engineering

Assignment Help:

Q. Interrupt - Driven Input-output?

Problem with programmed I/O is that processor has to wait a long time for I/O interface to see whether a device is free or waits until completion of I/O. Result is that the performance of processor goes down extremely. What is the solution? What about processor going back to do other useful work without waiting for I/O device to finish or get freed up? However how will processor be intimated about completion of I/O or a device is ready for I/O? A well-organized mechanism was considered for this which is referred to as interrupt-driven I/O. In this mechanism provision of interruption of processor work once device has completed I/O or when it's ready for I/O has been provided.

Interrupt-driven I/O mechanism for transferring a block of data is displayed in Figure 5(b). Please note after issuing a read command (for input) CPU goes off to do some other useful work whereas I/O interface proceeds to read data from connected device. On completion of an instruction cycle CPU checks for interrupts (that will happen when data is in data register of I/O interface and it now requires CPU's attention). Now CPU saves important register and processor status of executing program in a stack and requests I/O device to provide its data that is placed on data bus by I/O device. After taking needed action with data CPU can go back to program it was executing before interrupt.


Related Discussions:- Interrupt - driven input-output

How are devices represented in unix, How are devices represented in UNIX? ...

How are devices represented in UNIX? All devices are shown by files called special files that are located in /dev directory. Therefore, device files and other files are named a

Explain about bus of register transfer, Explain about Bus of register trans...

Explain about Bus of register transfer Since a computer has   several registers, paths must be provided to transfer information among registors. If separate lines are used amon

What are the benefits of micro programmed control, a. What are the benefits...

a. What are the benefits of hardwired and micro programmed control? b. Sketch neat diagram of single bus organization of CPU showing ALU, all types of registers and the data pat

What is static timing, What is Static timing a. Delays over all paths a...

What is Static timing a. Delays over all paths are added up. b. All possibilities, including false paths, verified without the need for test vectors. c. Faster than simul

What is read only memory (rom) and define the use of it?, What is Read only...

What is Read only memory (ROM) and Define the Use of it? A simple kind of ROM can be constructed from a decoder, Or gates, and a number of wires. Input

Explain the relationship b/w translated & load time address, Explain the re...

Explain the relationship amongst Translated address and Load time address. Translated address: Address assigned through the translator Load time address: Address ass

Implement and - or- not gates using bit wise operator, Q. Develop  a menu d...

Q. Develop  a menu driven program to implement AND, OR, NOT gates using and without using  Bit wise operator. The menu  should  be  as follows: I.  Using Bit Wise operator I

How e-commerce website works, Procedure The only difference between e-...

Procedure The only difference between e-commerce and conventional commerce is that goods in e-commerce are purchased over the internet using a credit card. Also buying and sel

Define ufd and mfd, Define UFD and MFD.   In the two-level directory st...

Define UFD and MFD.   In the two-level directory structure, every user has own user file directory (UFD). Every UFD has a same structure, but lists only the files of a single u

Explain working of counters, Q. Explain working of Counters? A counter ...

Q. Explain working of Counters? A counter is a register that goes through a predetermined sequence of states when clock pulse is applied. In principle value of counters is incr

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd