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

Explain logical shift micro-operations, Q. Explain logical shift Micro-oper...

Q. Explain logical shift Micro-operations? In logical shift data entering by serial input to left most or right most flip-flop (which depends on right or left shift operations

Basic working of network layer, Q. Basic working of Network layer? Net...

Q. Basic working of Network layer? Network layer: Network layer is responsible for routing a packet within the subnet that is, from source to destination nodes across numerou

Explain register marker, Explain Register marker. Register marker: St...

Explain Register marker. Register marker: Strowger selectors doing searching and counting. Conversely, the crossbar switch has no 'intelligence'. Something external to the

Explain in detail about first generation electronic computer, First Generat...

First Generation Electronic Computers (1937-1953) Three machines have been promoted at different times as first electronic computers. These machines used electronic switches

Computer science, Read in integers until a zero is read in. Keep a total o...

Read in integers until a zero is read in. Keep a total of both the quantity and the sum of the negative integers and the positive integers. Once a zero is read in (signifying the

Minimization of the logic function using k-maps, Minimize the logic functio...

Minimize the logic function F(A, B, C, D) = ∑ m(1,3,5,8,9,11,15) + d(2,13) using K-maps Ans. The logic function minimization of F(A, B, C, D) = ∑ m(1,3,5,8,9,11.15) + d(2,13) by

Example of prolog, Example of Prolog: We can say that this is also tru...

Example of Prolog: We can say that this is also true if there are four even numbers. Now we have our first rule: • If there are three or four even numbered cards, such play

Explain about the term- video conferencing, Video Conferencing Video co...

Video Conferencing Video conferencing continues to grow in popularity. Why is this? Some reasons are listed below: - Communication links are now much faster thus sound quali

What is a parallel port, What is a parallel port? A parallel port trans...

What is a parallel port? A parallel port transfers data in the form a number of bits, typically 8 to 16, concurrently to or from the device.

Speed of memory versus speed of CPU, In the past there was a large gap betw...

In the past there was a large gap between speed of a memory andprocessor. So a subroutine execution for an instruction for illustration floating point addition may have to follow a

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages