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 session_start subroutines, Can you give an example of what might be...

Can you give an example of what might be best suited to place in the application_Start and Session_Start subroutines? Application Start - We can place code to initialize var

Explain error-detection code, Q. (192.8)10 - (AE.E)16 = (X)8, Find value of...

Q. (192.8)10 - (AE.E)16 = (X)8, Find value of x. Use 8's complement method. Q. Write first 10 numbers in the base 4. Q. Explain Error-Detection code & Error-correction code w

Explain about the term middleware, Explain about the term Middleware. M...

Explain about the term Middleware. Middleware is the term frequently used to explain the application or business logic present within an application server. Unfortunately, simi

What is the difference between realloc() and free(), The free subroutine fr...

The free subroutine frees a block of memory lastly allocated by the malloc subroutine. Undefined results happen if the Pointer parameter is not a valid pointer. If the Pointer para

What is the difference between = = = and = =, What is the difference betwee...

What is the difference between = = = and = = ? output of "==" can be 1, 0 or X. output of "===" can only be 0 or 1. When you are comparing 2 nos using "==" and if one/bo

AWS, hosting on aws

hosting on aws

How to create a layout table in dreamweaver, Q. How to Create a Layout Tabl...

Q. How to Create a Layout Table in dreamweaver? In last section you used cells to create a table. Now, you will see how to start with a table and add cells later. 1.  In Obj

What is FIFO, What is FIFO? FIFO is used as buffering element or queui...

What is FIFO? FIFO is used as buffering element or queuing element into the system that is by common sense, is needed only while you slow at reading than the write operation.

Is it possible to decrease clock skew to zero, Is it possible to decrease c...

Is it possible to decrease clock skew to zero? Describe your answer? Even if there are clock layout strategies (H-tree) which can into theory reduce clock skew to zero by havi

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