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

Explain the term- macro, Explain the term- macro? A term macro is a set...

Explain the term- macro? A term macro is a set of instructions, which can be executed repeatedly. It is useful for automating certain routine tasks like printing reports etc. T

What is the use of digital switch, What is the use of digital switch? ...

What is the use of digital switch? Digital switch: This is a device which handles digital signals generated at or passed via a telephone company’s central office further

Describe the concept of aggregation, Aggregation Aggregation is a spec...

Aggregation Aggregation is a special form of association that models the "part-whole" or "a-part-of" relationship as an aggregate (the whole) and parts. The most important pro

What is a accepting computation history, What is a accepting computation hi...

What is a accepting computation history?  An accepting computation history is explained as , Let M be a Turing machine and w be a input string,  for M on w is a sequence of con

Write pseudocode, Ask question #Minimum 100 If today is a weekday and it’s ...

Ask question #Minimum 100 If today is a weekday and it’s not a holiday, then you go to work. However, if it’s a weekday and a holiday, then what you do depends on the weather: If i

Final implementation of object oriented modelling, Final Implementation of ...

Final Implementation of Object oriented modelling Final Implementation: At this phase, the final execution of classes and  relationships developed while object design takes

Explain the general model for the translation process, Write down the gener...

Write down the general model for the translation process. For the translation process the general model can be represented as given here:

Explain in detail about touch screens, Explain in detail about Touch screen...

Explain in detail about Touch screens For people who can't use a keyboard allowing input; also helps people with learning difficulties since icons are easier to understand

What is public-key infrastructures, a. What are the differences among conve...

a. What are the differences among conventional signatures and digital signatures? Write a short note on "Attacks on digital signature". b. What is Public-Key Infrastructures

Describe clusters in cellular systems, Question: a) With the help of a...

Question: a) With the help of a diagram, describe clusters in cellular systems. b) Describe the role of the following components in the GSM architecture Radio Sub-Sy

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