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
Standard Query Operators in LINQ can be used for working with collections for any of the following and more. 1. Get total count of elements in a collection. 2. Order the resu
ENCTYPE="application/x-www-form-urlencoded" and in its place use ENCTYPE="text/plain". The subsequent illustration displays a general form which includes some of the commo
Q. Observations of High Level Language Program? Observations Integer constants appeared nearly as frequently as structures or arrays. Most of the scalars were foun
Q. What do you mean by Loader? Loader is a program that assigns absolute addresses to program. These addresses are produced by adding the address from where program is loaded i
what is Asynchronous Finite State Machines?
Vector-Scalar Instructions In this category, when combination of vector and scalar are fetched and stored in vector register. These instructions are referred with the subsequen
What is Exact and Approximation algorithm? The principal decision to choose solving the problem exactly is called exact algorithm. The principal decision to choose solving th
"A datagram cannot be larger than the MTU of a network over which it is sent." Is the statement true or false? Explain with the help of a suitable example. All hardware technol
Memory utilization factor shall be computed as? Ans. memory in use/total memory connected.
Why is segmented paging important (as compared to a paging system)? Paging can be super-imposed upon a segment oriented addressing mechanism to acquire efficient use of the mem
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