External communication interfaces, Computer Engineering

Assignment Help:

External interface is interface between I/O interface and peripheral devices. Interface can be characterised into 2 main categories: (a) parallel interface and (b) serial interface.

In parallel interface multiple bits can be moved concurrently. Parallel interface is generally used for high-speed peripherals like tapes and disks. Dialogues which occur across interface include exchange of control information and data.

In serial interface just one line is used to transmit data so just one bit is transferred at a time. Serial printers are used for serial printers and terminals. With a fresh generation of high-speed serial interfaces so parallel interfaces are becoming less common.

In both cases I/O interface should engage in a dialogue with peripheral. Dialogue for a write or read operation is as follows:

  • A control signal is transmitted by I/O interface to peripheral requesting permission to send (for write) or receive (for read) data.
  • Peripheral acknowledges request.
  • Data are transferred from I/O interface to peripheral (write) or from peripheral to I/O interface (read).
  • Peripheral admits receipt of data.

Connection between an I/O interface in a computer system and external devices can be either P2P or multipoint. A P2P (point-to-point) interface provides a dedicated line between I/O interface and external device. For illustration keyboard, printer and external modems are point-to-point links. The most ordinary serial interfaces are RS-232C and EIA-232. 

Multipoint external interface used to support external mass storage devices (like disk and tape drives) and multimedia devices (like CD-ROM, video, audio).


Related Discussions:- External communication interfaces

Cookies, basic purpose of cookies

basic purpose of cookies

What is drop-down list, A dialog box such as a File menu that have one comm...

A dialog box such as a File menu that have one command until it is clicked when a number of dissimilar commands "drop-down."

Stack overflow causes, Stack overflow causes   (A) Hardware interrupt. ...

Stack overflow causes   (A) Hardware interrupt.  (B) External interrupt.  (C) Internal interrupt.   (D) Software interrupt. Stack overflow occurs whereas execution

State about the multiple inheritance, State about the multiple inheritance ...

State about the multiple inheritance multiple inheritance is shown in Figure. In this, one class is inherited from more than one class.

How does the race condition occur, It happens when two or more processes ar...

It happens when two or more processes are reading or writing some joint data and the final result depends on who runs exactly when.

Determine about the security- accidental damage, Determine about the securi...

Determine about the security- accidental damage accidental damage is best guarded against by keeping back up files or use Grandfather-Father-Son (GFS) method; also use of passw

Define deadlock, Define deadlock? Deadlock is a condition, wherein proc...

Define deadlock? Deadlock is a condition, wherein processes never finish executing and system resources are tied up, preventing another job from beginning. A process requests r

What are the differences between simulation and synthesis, What are the dif...

What are the differences between SIMULATION and SYNTHESIS Simulation synthesis Simulation is used to verify functionality of the circuit.. a) Functional Simulation:stud

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

Find the nyquist rate, Find the Nyquist rate for the following signals: (a)...

Find the Nyquist rate for the following signals: (a) x(t) = 5 sin 3000πt cos 4000πt (b) A binary channel with bit rate 36000 bps is available for PCM voice transmission. Fi

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