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

How will you prepare problem statement, How will you prepare problem statem...

How will you prepare problem statement? Problem statement should state what is to be completed and not how it is to be executed. It should be a statement of requirements not a

What is error checking, What is error checking? It computes the error c...

What is error checking? It computes the error correcting code (ECC) value for the data read from the given sector and compares it with the corresponding ECC value read from the

Write a program to perform multiplication of two numbers, Q. Write a progr...

Q. Write a program to perform multiplication of two numbers in specified radix. Check that entered numbers are in specified radix or not else error message should be displayed.

Computer graphics, What is intractive graphics and user dialouge in comput...

What is intractive graphics and user dialouge in computer graphics

Which transistor is used in every cell of eprom, Floating gate Avalanche In...

Floating gate Avalanche Injection MOS (FAMOS) transistor is used in every cell of EPROM.

Hidden input, Yet another type of input is HIDDEN input. A HIDDEN in...

Yet another type of input is HIDDEN input. A HIDDEN input is a value/name pair which is returned to you but doesn

Explain the term thread scheduling, Problem: a) Most RMI and RPC system...

Problem: a) Most RMI and RPC systems expect to be supported by the "Request-Reply Protocol". Describe what "Request-Reply Protocol" is. b) Describe the invocation semantics

Methods for organising the associative memory, There are two methods for or...

There are two methods for organising the associative memory based on bit slices: Bit parallel organisation: In this organisation every bit slices which are not masked off,

A full binary tree with ''n'' non-leaf nodes, A full binary tree with 'n' n...

A full binary tree with 'n' non-leaf nodes have  2n+l nodes.

Explain the term granularity, Granularity In 'Parallel computing', Gran...

Granularity In 'Parallel computing', Granularity can be defined as a qualitative assess of the ratio of computation to communication. 1) Coarse Granularity - relatively hug

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