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

Why java is called machine independent, Why Java is called Machine Independ...

Why Java is called Machine Independent? While a java program is compiled this is not converted in an executable code. Rather, this is converted in a byte code. Byte code is hig

What is backward compatible, A program is backward compatible if it can use...

A program is backward compatible if it can use files from an older version of itself. For a file saved in the program to be backward compatible, it must be possible to open the fil

What are the limitations of a cyclotron, Q. What are the limitations of a c...

Q. What are the limitations of a cyclotron? Limitations (i) Maintaining a consistent magnetic field over a large area of the Dees is difficult. (ii) At high rapidity

What is canonical and standard forms, Q.What is Canonical and Standard Form...

Q.What is Canonical and Standard Forms? An algebraic expression can express in two forms: i) Sum of Products   (SOP) for example (A . B¯) + (A¯ . B¯)            ii) Produ

What is the protocol used by sap gateway process, What is the protocol used...

What is the protocol used by SAP Gateway process? The SAP Gateway method communicates with the clients based on the TCP/IP Protocol.

Show the responsibilities of session layer, Q. Show the Responsibilities of...

Q. Show the Responsibilities of session layer? Session layer: Main functions of this layer are to establish, synchronize and maintain the interaction between two communicatio

Programming, how can compare alphabates of two words in c programming ?????...

how can compare alphabates of two words in c programming ?????

What is a deadlock, What is a Deadlock? Deadlock is a situation, in th...

What is a Deadlock? Deadlock is a situation, in that processes never complete executing and system resources are tied-up, preventing another job form starting. If the resou

Smallest and largest integer , A given microprocessor has words of 1 byte. ...

A given microprocessor has words of 1 byte.  What is the smallest and largest integer that can be characterized in the following representations?   a) unsigned b) sign- ma

Explain r-2r ladder d/a converter, Explain R-2R ladder D/A converter. A...

Explain R-2R ladder D/A converter. Ans. R-2R ladder D/A converter: An R-2R ladder D/A converter is shown in Fig.(a). It uses resistors of only two values R and 2R. The inp

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