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
Assignment: write a C program and a MASM procedure. The C program calls the MASM procedure to perform letter case conversion. Text sections covered: 12.1 to 12.3.1 Write a
Simulated Annealing: One way to get around the problem of local maxima, and related problems like ridges and plateaux in hill climbing is to allow the agent to go downhill to
Differentiate concurrent and parallel executions ? The words "parallel "and "concurrent" are often used interchangeably, however they are different. Parallel execution is connec
a. Initial State: The first or the default state the object is in. It is indicated by a solid circle. b. State: All the states an object can go in are mentioned in this. It is
What is Digitizers A common device for drawing, painting, or interactively selecting coordinate positions on an object is a digitizer. These devices can be used to input coordi
Design a circuit which computes the square of a number? This should not make use of any multiplier circuits. This should use Multiplexers and some other logic as: 1^2=0+1=1
Q. Define Immediate Addressing Mode with example? Immediate Addressing Mode An immediate operand can be a constant expression like a character, a number or an arithmetic e
Q. Explain the Passive Matrix in lcd technology? In a passive matrix arrangement LCD panel has a grid of vertical and horizontal conductors and every pixel is positioned at an
What is a half-adder? Explain a half-adder with the help of truth-table and logic diagram. Ans. Half Adder: It is a logic circuit for the addition of two 1-bit numbers is term
Using the memory map below; design an absolute decoding circuit. The technique is to spot the differences between the start and stop of each device. The Ram chip has the follow
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