Movsw/movsb-string manipulation instruction-microprocessor, Assembly Language

Assignment Help:

MOVSW/MOVSB : Move String Word or String Byte: Imagine a string of bytes, stored in a set  of consecutive memory locations is to be moved to another set of  the destination locations. Starting byte of the source string is located in the memory location whose address can be computed by using DS (data segment) and SI (source index) contents. Starting address of the destination locations where this string has to be relocated is given by ES (extra segment) and Dl (destination index) contents. Starting address of the source string is 10H*DS+[SI],  whereas the starting  address of the destination  string is 10H*ES+[DI].  The MOVSB/MOVSW instruction therefore, moves a string of bytes/ words pointed to by DS: SI pair (source) to the memory location pointed to by ES: Dl pair (destination).  The REP instruction prefix is utilized with MOVS instruction to repeat it by a value given in the register counter (CX). The length of word string or byte string ought to be stored in register CX register. Flags are remaining unaffected by this instruction.

After the MOVS instruction is executed, the index registers are automatically updated and register CX is decremented. The decrementing or incrementing of the pointers, for example DI and Sl depend on the direction flag DF. If flag DF is 0, the index registers are incremented, or else, they are decremented, in all casa of the string manipulation instructions. Following string of instructions explain the execution of the MOVS instruction.

Example :

1000_movsb.jpg


Related Discussions:- Movsw/movsb-string manipulation instruction-microprocessor

Or-logical instruction-microprocessor, OR: Logical OR: The OR instruction ...

OR: Logical OR: The OR instruction carries out the OR operation in the similar way as described in case of the AND operation. The restriction on source and destination operands ar

Prepare the assembly code sequence, Problem (a) Prepare the assembly c...

Problem (a) Prepare the assembly code sequence for each of the four styles (accumulator, memory-memory, stack, load/store) of machine for the code fragment: A = B + C;

Data copy/transfer instructions-microprocessor, Data copy/transfer Instruct...

Data copy/transfer Instructions MOV: This data transfer instruction transfers data from one register or memory location to another register or memory location. The source can

Program to perform one byte bcd addition-assembly program, Program : Write...

Program : Write a program to perform a one byte BCD addition. Solution : It is consider that the operands are in BCD form, but the CPU considers it as hexadecimal and acco

8086, Write a program to mask bits D3D2D1D0 and to set bits D5D4 and to inv...

Write a program to mask bits D3D2D1D0 and to set bits D5D4 and to invert bits D7D6 of ax register

#title, how i can write a program to divide 2 numbers

how i can write a program to divide 2 numbers

Name-offset-assemblers directive-microprocessor, NAME : Logical Name of...

NAME : Logical Name of a Module: The NAME directive which is used to assign a name to an assembly language program module. The modulecan now be mention to by its declared name.

Dq-dt-assemblers directive-microprocessor, DQ:   Define  Quad word:-  Th...

DQ:   Define  Quad word:-  This directive is taken in use to direct the assembler to reserve 4 words (8 bytes) of memory for the specified variable and can initialise it having

Assembly - Zombie Game using Irvine & Visual 2010, http://www.raritanval.ed...

http://www.raritanval.edu/uploadedFiles/faculty/cs/full-time/Brower/CISY256/2013Spring/CISY256%20Assembly%20Project.pdf

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