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

What is sap dispatcher, What is SAP dispatcher? SAP dispatcher is the co...

What is SAP dispatcher? SAP dispatcher is the control agent that handles the resources for the R/3 applications.

Determine the values of the output of the logic gates, Write the values of ...

Write the values of the C output for the following gates: For a(n) ________ gate, the output is zero if any of the inputs are equal to  one. For a(n) ________ gate ,the

Describe about address space and memory space, Q. Describe about Address Sp...

Q. Describe about Address Space and Memory Space? An address used by a programmer will be termed as a virtual address and set of such addresses the address space. An address in

Constants - first-order logic, Constants - first-order logic: Constant...

Constants - first-order logic: Constants are things that is cannot be changed, like as england, black and barbara. So then they stand for one thing only, so that can be confu

Electing neil, ELECTING NEIL : The response for this is, of course. In...

ELECTING NEIL : The response for this is, of course. In this case, we considered the point of the search or researching is to find an artifact  -  a word which is an anagram o

Determine the use of loop instruction, Q. Determine the use of LOOP instruc...

Q. Determine the use of LOOP instruction? Program: This program prints the alphabets (A-Z) ; Register used: AX, CX, DX CODE SEGMENT ASSUME: CS: CODE.     MAINP:

Show the two ways in which warnings can be suppressed in php, Show the two ...

Show the two ways in which Warnings can be suppressed in PHP? 1) Stop an individual function call from producing an error message put the @ warning suppression Operator front o

Produce an analysis model of the proposed system, Question: Read the fo...

Question: Read the following case study and answer the questions based on it. The local airline company needs to develop a system for controlling air traffic at the airport

Benefits of traditional hard disks and cd-rom, Q. Benefits of traditional h...

Q. Benefits of traditional hard disks and CD-ROM? CD-ROM is suitable for distribution of large amounts of data to a large number of users. CD-ROMs are a general medium these da

Mac and llc, how can we improve the way LLC and MAC are used for LAN operat...

how can we improve the way LLC and MAC are used for LAN operation.?

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