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

Gather some ram data after system was powered off, (a) When a forensic exa...

(a) When a forensic examiner arrives at a crime scene, the first task done is referred to as "Incident Response". Summarize the different incident response tasks done in 10 steps.

Keys, why impotant keys

why impotant keys

Define underflow and overflow, Define underflow and overflow. Underflow...

Define underflow and overflow. Underflow: If the result the arithmetic operation including n-bit numbers is too small to show by n-bits, underflow is said to occur. Overflow

Explain about quine mckluskey method, Q. Explain about Quine McKluskey Meth...

Q. Explain about Quine McKluskey Method? A tabular method was proposed to deal with increasing number of variables called Quine McKluskey Method. This method is appropriate for

What is boundary scan, What is Boundary Scan?  Boundary scan is a board...

What is Boundary Scan?  Boundary scan is a board level design method that provides test access to the input and output pads of ICs on PCBs. Boundary scan changes the IO circuit

Student, Suppose we have an array-based list A[0..N - 1] and we want to del...

Suppose we have an array-based list A[0..N - 1] and we want to delete all duplicates. LastPosition is initially N - 1, but gets smaller as elements are deleted. Consider the pseudo

Define deadlock, Define deadlock? Deadlock is a condition, wherein proc...

Define deadlock? Deadlock is a condition, wherein processes never finish executing and system resources are tied up, preventing another job from beginning. A process requests r

Explain the terms constructors and destructors, When we initialize the form...

When we initialize the form at that time if we require to set any variable's value then we can set it by defining in constructor. Constructor's name always similar as class name an

Distinguish between min terms and max terms, Distinguish between min terms ...

Distinguish between min terms and max terms. Ans Differentiate between Minterms and Maxterms: a. Each single term in standard Sum Of Products (SOP) form is termed as minterm

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