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

Forward chaining - artificial intelligence, Forward Chaining - Artificial i...

Forward Chaining - Artificial intelligence: Imagine we have a set of axioms which we know are true statements regarding the world. If we set these to each be a starting state o

Sigmoid units-artificial intelligence, Sigmoid units - Artificial intellige...

Sigmoid units - Artificial intelligence Remember that the function inside units take as input the weighted sum, S, of the values coming from the units associated to it. The fun

Explain advantage of static storage class, Explain advantage of static stor...

Explain advantage of static storage class The second and more subtle use of 'static' is in connection with external declarations. With external constructs it provides a privacy

Message passing programme development environment, In a multicomputer syste...

In a multicomputer system the computational load amid different processors should be balanced.  To pass information between different nodes message passing technique is used. The p

Permanently resident pages - main memory, Permanently resident pages: ...

Permanently resident pages: Every virtual memory systems have memory areas that are "pinned down", for example cannot be swapped out to secondary storage, for instance:

Which device changes from serial data to parallel data, Which device change...

Which device changes from serial data to parallel data ? Ans. Demultiplexer is the device that changes from serial data to parallel data. Demultiplexer takes data in from on

Advantage and disadvantage of threaded binary trees, Advantage  1.     ...

Advantage  1.       By doing threading we neglect the recursive method of traversing a Tree , which makes use of stack and consumes many memory and time . 2.       The node

Binary search tree, Given the following interface public interface WordS...

Given the following interface public interface WordSet extends Iterable { public void add(Word word); // Add word if not already added public boolean contains(Word word);

Zero address instruction format, Zero address instruction format is used fo...

Zero address instruction format is used for  (A) RISC architecture.      (B) CISC architecture.  (C) Von-Neuman architecture.   (D) Stack-organized architecture.

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