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

Human computer interaction, Preamble The owner of the local shopping mal...

Preamble The owner of the local shopping mall, MaxiMart, has contracted you to assist in the design of an interactive directory. The interactive directory is to be permanently l

Logic-based expert systems - artificial intelligence, Logic-based Expert Sy...

Logic-based Expert Systems - Artificial intelligence: Expert systems are agents which are programmed to make decisions about real world situations. They are put together by uti

Arrays, how to calculate students''s averange test scores

how to calculate students''s averange test scores

Illustrate the ftp commands, Q. Illustrate the FTP commands? FTP includ...

Q. Illustrate the FTP commands? FTP includes many commands however only few are used to retrieve a file. A user is required to understand the three basic commands to connect to

C++, pebble merchant

pebble merchant

What is process, In Windows, Thread is a unit of implementation. Process is...

In Windows, Thread is a unit of implementation. Process is the environment in which thread implements. Scheduler, schedules the Threads not the process. In Unix variants, Thread is

What do you mean by data distribution, Q. What do you mean by Data Distribu...

Q. What do you mean by Data Distribution? Data distribution directives tell compiler how program data is to be distributed among memory areas connected with a group of processo

What is the application of e-commerce in home shopping, What is the applica...

What is the application of E-Commerce in Home Shopping? Application of E-Commerce in Home Shopping: Television broadcast of goods for purchase sent it directly to a viewe

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