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
Define the role of organizationin computer architecture The organization is the set of resources that realizes the architecture which include the CPU, the memory and I/O contro
Structure of Internet Servers Address Structure of an Internet server's address keyed into a client's software is as below: http://www.expertsmind.com Where: htt
What are different normalization forms? 1NF: Eliminate Repeating Groups Make a separate table for every set of related attributes, and give each table a primary key. Each fie
quick sort working
Computer Memories Computer memories are either external or internal. Internal memories are either RAM (random access memory) or ROM (read only memory). External memories can t
What is a Priority Interrupt? A priority interrupt is an interrupt that establishes a priority over the various sources to determine which condition is to be serviced first whe
Determine the Framed data including a parity bit For illustration when even parity is chosen, parity bit is transmitted with a value of 0 if the number of preceding
What do you understand by WWW? WWW (World Wide Web): It is an architectural framework for accessing linked documents outspread over thousands of machines the whole world.
Distinguish between uniform scaling differential scaling
Discuss the risks of having a single root user and how more limited management abilities can be given to others users on Linux/UNIX systems
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