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

What is pointers function, Visual basic applications have very rich and fle...

Visual basic applications have very rich and flexible applications but there is single limitation when using pointer function. Windows API has limited support for function pointers

Define the term package- object oriented modeling, Define the term package-...

Define the term package- object oriented modeling A package is a common purpose mechanism for organising elements into groups. Package can also contain other packages. The no

Illustrate what is a ion pair energy, Q. Illustrate what is a ion pair ener...

Q. Illustrate what is a ion pair energy? Answer:- Ion energy contains electric charges called protons (+) and neutrons (0) and electrons (-) charges. It's present in an at

What is the use of boot block, What is the use of boot block? For a com...

What is the use of boot block? For a computer to start running when powered up or rebooted it needs to have an initial program to run. This bootstrap program tends to be simple

Encryption techniques to ensute secured transaction on net, Two popular enc...

Two popular encryption techniques to ensute secured transactions on the net? 1. Translation table 2. Word/byte rotation and XOR bit masking.

Blocking and non-blocking network, Blocking and Non-Blocking network In...

Blocking and Non-Blocking network In non-blocking networks the route from any free input node to any free output node can always be offered. Crossbar is an best example of non-

Internal organisation of memory chips, expplain in detail the internal orga...

expplain in detail the internal organisation of computer?

Construct a shift register from S-R flip-flops, Construct a shift register ...

Construct a shift register from S-R flip-flops. Explain its working. Ans: S-R Flip-Flop Shift Register: Shift registers can be built through using SR flip-flops. Fig.(a)

Draw the logic circuit using NOR gates using K-map, Draw the logic circuit ...

Draw the logic circuit using minimizaed equation by K-map for the simplified function using NOR gates only. F (A, B, C, D) = Π M (1, 2, 3, 8, 9, 10, 11,14) ⋅ d (7, 15) Ans

Accessing the internet, Before we can use Internet, we have to gain access ...

Before we can use Internet, we have to gain access to it. This access is achieved in one of numerous ways. Above all, the Internet is a collection of networks which are connected t

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