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 literal, Meaning of Literal is:- Literal is string constant.

Meaning of Literal is:- Literal is string constant.

What is the use of isolated i/o configuration, What is the use of isolated ...

What is the use of isolated I/O configuration.  In isolated I/O configuration the CPU has distinct input and output instructions and each of these instructions is associated wi

Why a linked list is called a dynamic data structure, Why a linked list is ...

Why a linked list is called a dynamic data structure? What are the advantages of using linked list over arrays?    A linked list is known as a dynamic data structure because it

Computer graphics, what isAdvantages of scan line algorithm, Computer Graph...

what isAdvantages of scan line algorithm, Computer Graphics?

Explain floating point arithmetic pipelines, Floating point Arithmetic pipe...

Floating point Arithmetic pipelines Floating point calculations are the best candidates for pipelining. Take the illustration of addition of two floating point numbers. Subsequ

Illustrate why does a tea kettle sing, Q. Illustrate why does a tea kettle ...

Q. Illustrate why does a tea kettle sing? Answer:- There is a little attachment with a hole in it which acts as a whistle. It is inserted into the spout of the kettle as w

Why we need number systems, Q. Why we need number systems? Number syste...

Q. Why we need number systems? Number system is used to signify information in quantitative form. Some of the general number systems are octal, decimal, hexadecimal and binary.

Multi tasking environment, Q. Explain about Multi tasking environment? ...

Q. Explain about Multi tasking environment? Multi tasking uses parallelism by: 1) Pipelining functional units are pipe line mutually 2) Simultaneously employing multiple

Recursion, Ask qurecurrion for short noteestion

Ask qurecurrion for short noteestion

Pros and cons of general purpose register architecture, Q. Pros and Cons of...

Q. Pros and Cons of general purpose register architecture? General Purpose Register Architecture: Pros and Cons Registers can be employed to store variables as it decrea

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