String manipulation instruction-microprocessor, Assembly Language

Assignment Help:

String Manipulation Instruction

A series of words or data bytes are available in memory at consecutive locations, to be mention to individually or collectively, are known as byte strings or word strings or byte strings. For instance, a string of characters can be located in consecutive memory locations, where each character can be represented by its ASCII equivalent. For mention to a string, two parameters are needed,

(a) Length of the string and

(b) Starting or ending address of the string.

The length of a string is generally stored as count in the CX register. In case of 8085, same structures may be set up by counter and the pointer arrangements.  The counters and pointers can be modified at each iteration until the needed condition for proceeding further is satisfied. Instead, the 8086 supports a set of more powerful instructions for string manipulations.  In case of 8086 string instructions, the decrementing or incrementing of the pointer depends on the direction flag (DF) status. If it is a byte string operation then the index registers are updated by one. Instead, if it is a word string operation then the index registers are updated by two. The counter in both of the cases is decremented by one. It consisits of REP, MOVSW/MOVSB, CMPS, SCAS, LODS, STOS.

 


Related Discussions:- String manipulation instruction-microprocessor

Ror-logical instruction-microprocessor, ROR : Rotate Right without Carry: ...

ROR : Rotate Right without Carry: This instruction rotates the contents of destination operand to the bit-wise right either by one or by the count specified in register CL, exclud

Space don''t come in ASCII characters while printing?, .MODEL SMALL .STACK...

.MODEL SMALL .STACK 100H .DATA PROMPT DB \''The 256 ASCII Characters are : $\'' .CODE MAIN PROC MOV AX, @DATA ; initialize DS MOV DS, AX

Introduction to 80 x 86 assembly language, Using the windows32 framework, w...

Using the windows32 framework, write a complete 80x86 program for Programming Exercises 4.3 number 3, on pages 130-131 of the textbook. Follow all coding conventions mentioned in

Into-jmp-unconditional branch instruction-microprocessor, INTO : Interrupt...

INTO : Interrupt on Overflow:- It is executed, when the overflow flag OF is set. The new contents of IP and CS register are taken from the address 0000:0000 as described in INT

Add-arithmetic instruction-microprocessor, ADD:  Add :- This instruction ...

ADD:  Add :- This instruction adds an immediate contents of a memory location specified in the a register ( source ) or instruction to the contents of another register (destinat

Display control-microprocessor, Display control 8279  provides  a  16  ...

Display control 8279  provides  a  16  byte  display  memory  and  refresh  logic.  Every address in the display memory corresponds to a display unit with address zero represen

Program on virtual learning environment, Task One Produce a menu such a...

Task One Produce a menu such as the one below (remember to keep to this specification). M E N U 1, Enter Number 1 2, Enter Number 2 3, Display num1 and num2 4, D

.., Sum of series of 10 numbers and store result in memory location total

Sum of series of 10 numbers and store result in memory location total

Ddition, Write a program that performs the addition, subtraction, multiplic...

Write a program that performs the addition, subtraction, multiplications, division of the given operands. Perform BCD operation for addition and subtraction.

Program that will compute and output tuition cost, Write an assembly progra...

Write an assembly program that will compute and output tuition cost: a. accept keyboard input of the number of credit hours taken b. accept keyboard input of the type of classes 1

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