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 a good resolution, Q. What is a good resolution? In fact it rel...

Q. What is a good resolution? In fact it relies on your hardware. Hence it's the maximum your hardware can allow you.  But one odd-looking resolution that has become popular is

Explain conditions for the critical section problem solution, What are the ...

What are the properties which a data item should possess to implement a critical section? The Critical Section Problem Solution should satisfy the following conditions: 1.

Explain the architectural description languages, Explain the Architectural ...

Explain the Architectural description languages Architectural description languages (ACLs) have been developed for the architectural description in analysis and design process

Determining the error models that affect program execution, In critical com...

In critical computer applications the correctness of a delivered output and the continuity of the required service beside the speed of the used CPU are the most important measures

Provision for data buffering, Data buffering is quite helpful for purpose o...

Data buffering is quite helpful for purpose of smoothing out gaps in speed of processor and I/O devices. Data buffers are registers that hold I/O information temporarily. I/O is pe

Define optimistic synchronization, Q. Define Optimistic Synchronization? ...

Q. Define Optimistic Synchronization? Optimistic Synchronization: This method too updates atom by requester process however sole access is granted after atomic operation by abo

Applications of generic framework for electronic commerce, How are the appl...

How are the applications of generic framework for electronic commerce performed? To perform applications, this is essential to have Supporting Information and Organizational In

When page fault frequency in an operating system is reduced, Page fault fre...

Page fault frequency in an operating system is reduced when the? When locality of reference is appropriate to the process so Page fault frequency in an operating system is redu

Dram simm, The most common type of non-volatile memory is the ROM device. T...

The most common type of non-volatile memory is the ROM device. This device is read only and the data is masked into the chip during manufacture. Variations of the ROM are one off p

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