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

Make a generalized program that accepts a number and base, Q. Make a gener...

Q. Make a generalized program that accepts a number & base, convert it into the given base. Perform necessary validations.

Define a register, Define a register. Ans:  Register:   A register...

Define a register. Ans:  Register:   A register contain a group of flip-flops and gates which effect their transition. The flip flops hold the binary information and the g

Code Solution, Dear sir, I want to read Excel file and display it in grid v...

Dear sir, I want to read Excel file and display it in grid view(the headings in excel file should be grid view column heading).This should be coded in C# Windows forms Application

Describe jmx concepts and architecture, MX is conceptually easy, yet bears ...

MX is conceptually easy, yet bears the fruit of years of domain experience and research. In a nutshell, JMX describes a standard means for applications to expose management functio

Mapping design principle, The following definition of mapping is adapted fr...

The following definition of mapping is adapted from the first edition of the Set Book: Mapping concerns the relationship between controls and their effects in the world. Nearly al

Nmknl''knl, Ask question bhjjnjnnjnjm#Minimum 100 words accepted#

Ask question bhjjnjnnjnjm#Minimum 100 words accepted#

Explain about common addressing modes, Q. Explain about common addressing m...

Q. Explain about common addressing modes? Most of machines use a set of addressing modes. The following tree displays common addressing modes: Figure: Common Addres

Calculate blocking probability in a two stage network, In a two stage netwo...

In a two stage network there are 512 inlets and outlets, r=s=24. If the probability that a given inlet is active is 0.8, calculate: Blocking probability Given: N =M =512,

How can we access the correction and transport system, How can we access th...

How can we access the correction and transport system? Each time you make a new object or change an existing object in the ABAP/4 Dictionary, you branch automatically to the W

Give brief summary of common aspects found in spreadsheets, Give brief summ...

Give brief summary of common aspects found in spreadsheets -  It's made up of columns and rows; every row is identified by a number and every column is identified with a letter

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