Io devices and i/o subsystem and direct memory access, Computer Engineering

Assignment Help:

Why IO devices cannot be connected directly to the system bus?

Ans: The IO devices can't be directly connected to the system bus because the following reason

A) The data transfer rate of IO devices is slower that of CPU.

B) The IO devices in computer system has different data formats and work lengths that of CPU. So it is essential to use a module between system bus and IO device which is called IO module or IO system

Write the factors considered in designing an I/O subsystem?

 Ans:

1. Data transfer: Amount, rate to or from device.

 2. Data Location: Device selection, address of data within device (track, sector etc)

3. Memory or between an I/O device and CPU.

4. Synchronization: Output only when device is ready, input only when

Described Direct Memory Access

Ans: A modest increase in hardware enables an IO device to transfer a block of information to /from memory without CPU intervention. This task needs the IO device to produce memory addresses and transfer data via the bus by using interface controllers.

 


Related Discussions:- Io devices and i/o subsystem and direct memory access

Determine the bandwidth requirement of a telephone channel, The bandwidth r...

The bandwidth requirement of a telephone channel is (A)  3 KHz                                      (B)  15 KHz (C)  5 KHz                                      (D)  25 KH

What is a thread, What is a thread? A thread otherwise called a lightwe...

What is a thread? A thread otherwise called a lightweight process (LWP) is a basic unit of CPU utilization, it comprises of a thread id, a program counter, a register set and a

Draw logic circuit for the simplified function, Minimize the logic function...

Minimize the logic function Y(A, B, C, D) = ∑m(0,1,2,3,5,7,8,9,11,14). Use  Karnaugh map. Draw logic circuit for the simplified function. Ans: In following figure (a) shows the

Significance of having less memory references, Q. What is the significance ...

Q. What is the significance of having less memory references? As the time needed for memory reference is more than that of a register reference so increased number of memory r

Explain about cd-rom and dvd-rom, Q. Explain about CD-ROM and DVD-ROM? ...

Q. Explain about CD-ROM and DVD-ROM? Optical disks employ Laser Disk Technology that is the latest and most promising technology for high capacity secondary storage. Advent of

Method of spirit duplicating, Method : The master from which the copies wi...

Method : The master from which the copies will be taken is first prepared from a special non-absorbent glazed sheet of paper and special carbon paper which acts as the reproducing

Automatic typewriter in information distribution, Automatic typewriter : I...

Automatic typewriter : It is a power-driven machine, which automatically types a standard pro forma from a previously punched or stencilled master. When the master is placed on th

Explain the working of a 1-to-16 Demultiplexer, Using a suitable logic diag...

Using a suitable logic diagram explain the working of a 1-to-16 de multiplexer. Ans. 1-to-16 Demultiplexer Working: A demultiplexer obtains in data from one line and directs this

Define the register addressing mode, Q. Define the Register Addressing mode...

Q. Define the Register Addressing mode? When operands are taken from registers implicitly or explicitly it is known as register addressing. These operands are termed as regis

An example subroutine call, Create your own Subprogram that does *not* use ...

Create your own Subprogram that does *not* use any input parameters. You decide the theme. You should give the pseudocode and an example Subroutine call. Be sure to give an overvie

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