Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
INT 21H supports about 100 different functions. A function is recognised by putting the function number in AH register. For illustration if we want to call function number 01 then we place this value in AH register first by employing MOV instruction and after that call INT 21H:
Some significant DOS function calls are:
DOS
Function Call
Purpose
Example
AH = 01H
For reading a single character from keyboardand echo it on monitor. The input value is put inAL register.
To get one character input in a variable in data segment you may include the following in the code segment:
MOV AH,01
INT 21H
MOV X, AL
(Please note that interrupt call will return value in AL which is being transferred to variable of data segment X. X must be byte type).
AH = 02H
This function prints 8 bit data (normally ASCII) that is stored in DL register on the screen.
To print a character let say '?' on the screen we may have to use following set of commands:
MOV AH, 02H;
MOV DL, '?'
AH = 08H
This is an input function for inputting one character. This is same as AH = 01H functions with the only difference that value does not get displayed on the screen.
Same example as 01 can be used only difference in this case would be that theinput character wouldn't get displayed
MOV AH, 08H
AH = 09H
This program outputs a string whose offset is stored in DX register and that is terminated using a $ character. One can print newline, tab character also.
To print a string "hello world" followed by a carriage return (control character) we may have to use the following assembly program segment.
Example of
CR EQU ODH
; ASCII code of carriage return.
DATA SEGMENT
STRING DB 'HELLO WORLD', CR, '$'
DATA ENDS
CODE SEGMENT
:
MOV AX, DATA
MOV DS, AX
MOV AH, 09H
MOV DX, OFFSET STRING
; Store the offset of string in DX register.
AH = 0AH
For input of string up to 255 characters. The stringis stored in a buffer.
Look in the examples given.
AH = 4CH
Return to DOS
The Concept of Process Unofficially a process is a program in execution subsequent to the program has been loaded in the main memory. Though a process is more than just a progr
Software Engineering is a layered technology. Explain
What is a pre-processor? A pre-processor is a program that procedure the source code before it passes by the compiler. It handles under the control of pre-processor directive.
Multithreading is the process in which more than single thread run independent of each other within the process in any programming language such as C, C++, etc.
Question: (a) Identify the four main enhancements brought along by TKIP on WPA to solve the problems in WEP. (b) The term WarDriving has been frequently used while talking
Take a look at the code and try to understand the logic, particularly, the way scrambled words are disambiguated, i.e.., whether they are matched successfully against a correct wor
Write "heterogeneous" functions If a program uses simulated, dynamically allocated multidimensional arrays, it becomes possible to write "heterogeneous" functions which don't h
Find how many bits of ADC are required to get an resolution of 0.5 mV if the maximum full scale voltage is 10 V Ans. Given Resolution=.5mV Full scale output=+10v %resolut
Given a dataset with 1000 rows and 25 predictors labeled x1, x2, ...,x25 to classify into two classes {a, b}. Consider the small random forest with 3 trees and one split in each tr
Discuss the various functions of telephone switching systems. Telephone switching system's functions are as follows: (i) Attending: The system should be continually monito
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd