Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
After going through details of device interfaces next point to be discussed is how the interface can be used to support I/O from devices. Binary information received from an external device is generally stored in memory for later processing. Information transferred from central computer in an external device initiates in memory unit. Data transfer between central computer and I/O devices can be handled in some modes. 3 techniques are possible for I/O operation. These are:
Figure below gives an general idea of these 3 techniques:
Figure: Overview of the three Input/ Output
In programmed I/O, I/O operations are fully controlled by processor. The processor executes a program which initiates, directs and terminate an I/O operation. It needs a little special I/O hardware however is quite time consuming for processor as processor has to wait for slower I/O operations to finish.
With interrupt driven I/O when interface decides that device is ready for data transfer it produces an interrupt request to the computer. Upon detecting external interrupt signal processor stops the task it was processing and branches to a service program to process I/O transfer and then returns to task it was initially performing that result in waiting time by the processor being reduced.
With both interrupt-driven and programmed I/O processor is responsible for extracting data from main memory for output and storing data in main memory during input. What about having a substitute where I/O device may directly store data or retrieve data from memory? This alternative is called direct memory access (DMA). In this mode I/O interface and main memory exchange data directly without involvement of processor.
Figure: Three techniques of I/O
Which language is a platform free language Java language
Develop a regular expression for (i) Integer (ii) Real number (i) A regular expression for integer is [+ | -] (d)+ (ii) A regular expression for real number is [+
What are the Digital certificates of hardware computations Digital certificates are highly dependent on hardware computations, it is essential that mechanisms are evolved to i
Takes care structural and behavioural aspect of a software system. Contains software usage, functionality, performance, economic, reuse, and technology constraints.
a. Activity diagram: Activity diagram is used for functional modelling. Captures the process flow. b. Sequence diagram : Sequence diagram is used for dynamic modeling.
reflection in 2d
Why The JavaScript Validation Not Run on the Asp.Net? The Asp.Net Button Is post backed on the server & not yet Submit & when it goes to the server its states is lost so if we
In a subscriber loop that contains a series resistance of 300 ohms to protect the batteries in the exchange, a normalized telephone draws 10 mA and its standard input d.c. resistan
Why is catch (Exception) almost always a bad idea? Well, if at that point you know that an error has happened, then why not write the proper code to handle that error instead
The scheduling in which CPU is allocated to the process with least CPU-burst time is called? Ans. Shortest job first Scheduling wherein CPU is allocated to the process with lea
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd