What do you understand by scan codes, Computer Engineering

Assignment Help:

Q. What do you understand by Scan Codes?

A scan code is a code produced by a microprocessor in keyboard when a key is pressed and is unique to key struck. When this code is received by computer it reports an interrupt and looks up scan code table in BIOS and realize which keys have been pressed and in what combination. Special memory locations known as status bytes tell the status of locking and toggle keys for example Caps lock etc. Every key press produces two different scan codes - one on key-push down known as Make code and another on its popping back known as Break code. This two-key scheme enables the computer to tell when a key is held pressed down for example ALT key when pressing another key say CTRL-ALT-DEL.


Related Discussions:- What do you understand by scan codes

C programming, You are given a collection of words, say as in a dictionary....

You are given a collection of words, say as in a dictionary. You can represent it in the following compressed form: the first word will be followed by a sequence of a pair of numbe

Reprographic methods for information distribution, Reprographic Methods ...

Reprographic Methods i) Thermography ii) Dyeline jii) Microfiche iv) Fax In this unit you have learnt that: Used for Methods of reprography are used for the

Determine the benefits of developing prototype, Determine the benefits of d...

Determine the benefits of developing prototype According to SOMM [96] benefits of developing prototype are as following:  1.  Communication gap between clients and software

Advantages on electronic payment system, Advantages on electronic payment s...

Advantages on electronic payment system It gives good security schemes.  Four necessary security requirements for safe e-payments are Authentication, Encryption, Integrity,

What do you understand by work flow automation, What do you understand by w...

What do you understand by work flow automation? Work Flow Automation: Organizations often standardize processes over the organization and encourage users to adopt them. Ev

Explain simple telephone communication system, Explain simple telephone com...

Explain simple telephone communication system with circuit and equation of current flow in microphone? Simple Telephone Communication: In the simplest type of a telephone cir

What are digital signatures and its uses, What are Digital Signatures and i...

What are Digital Signatures and its uses? A digital signature is an electronic quite than a written signature which can be used through someone to authenticate the identity of

What is pure semiconductors, Q. What is Pure semiconductors? Pure semic...

Q. What is Pure semiconductors? Pure semiconductors, known as intrinsic semiconductors, have very few charge carriers and may hence be classified as almost insulators or very p

Explain naming convention in arrays, Explanation Arrays in many programm...

Explanation Arrays in many programming-languages generally show a fixed list of values (e.g. a list of lastnames). Though within SQABasic the size for an array can either be fix

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