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

3D rotation, Magnify a triangle with vertices A = (0,0), B = (3,3) and C = ...

Magnify a triangle with vertices A = (0,0), B = (3,3) and C = (6,4) to twice its size in such a way that A remains in its original position.

How many flip flops are required to construct decade countr, How many flip ...

How many flip flops are required to construct a decade counter ? Ans. 4 FlipFlop's are required because decade counter counts 10 states from 0 to 9 (that is from 0000 to 1001).

Explain the state space of search problem, Question: (a) Assume you are...

Question: (a) Assume you are a taxi driver. Your taxi can hold four passengers. Passengers pay a flat fee for a ride to the airport, so your goal is to pick up four passengers

How speech is transmitted in a digital switching environment, How speech is...

How speech is transmitted in a digital switching environment using PCM/TDM? A digital carrier system is a communications system which uses digital pulses quite than analogue si

Develop a program octal to hexadecimal, Q.  Develop a Menu driven program w...

Q.  Develop a Menu driven program with following menu: 1.  Octal to Decimal 2.  Octal to Hexadecimal 3.  Octal to Binary

Explain the term- scan insertion, Explain the term- Scan Insertion Sca...

Explain the term- Scan Insertion Scan Insertion is completed by a tool and results in all (or most) of your design's flip-flops to be changed by special "Scan Flip-flops". Sca

Eight-stage process - conjunctive normal forms, Eight-stage process - Conju...

Eight-stage process - Conjunctive normal forms: Hence we notice the following eight-stage process converts any sentence with CNF as:  1.  Eliminate all arrow connectives by

Bank prevent an infinite loop, a) Write a program that figures out how long...

a) Write a program that figures out how long it will take to pay off a credit card by making payments of $10 every month. Take care to avoid infinite loops. (How would a bank preve

Define a socket, Define a socket? An application program interface give...

Define a socket? An application program interface gives the details of how can an application program interacts along with protocol software. But socket API is a defacto standa

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