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

Describe functions of data flow diagram, Describe functions of data flow di...

Describe functions of data flow diagram After you have roughly designed data flow diagram, you could write a description of each function and you could describe the function i

Explain characteristics of prototyping, Question: (a) List five main c...

Question: (a) List five main characteristics of ‘Prototyping'. (b) Describe briefly why ‘Prototyping' is essential to Rapid Application Development. (c) Describe the 2 t

Flowchart, how can we find compound interest through flowchart

how can we find compound interest through flowchart

Largest and the second largest number, The largest and the second largest n...

The largest and the second largest number from a set of n distinct numbers can be found in    O (n)

Difference between abstract class and interface, Abstract class: Abstract c...

Abstract class: Abstract classes are the class where one or more methods are abstract but not essentially all method has to be abstract. Abstract methods are the methods, which are

What does the term entrepreneurship mean, 1) What does the term entrepreneu...

1) What does the term entrepreneurship mean to you?  What are some basic characteristics of entrepreneurs? 2) What is e-commerce?  Why are the Internet economy and e-commerce he

C++ program on pebble merchant, how to solve pebble merchant problem.? codi...

how to solve pebble merchant problem.? coding for it..!

What are advantages and drawbacks of flip-flop, What are advantages and dra...

What are advantages and drawbacks of flip-flop? Usually area of a Flip-flop for features in more than a latch. Power consumption is normally higher, because of the area and

What is assembler, Q. What is Assembler? An assembly program is used to...

Q. What is Assembler? An assembly program is used to transfer assembly language mnemonics to binary code for every instruction after the complete program has been written with

Differentiate the latch and flip-flop, Differentiate the latch and flip-flo...

Differentiate the latch and flip-flop? The major difference between latch and FF is which latches is level sensitive whereas FF is edge sensitive. They both need the use of clo

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