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

Assume-assemblers directive-microprocessor, ASSUME: Assume Logical Segment...

ASSUME: Assume Logical Segment Name:- The ASSUME directive which is used to inform the assembler, the specified names of the logical segments to be consider for different segme

Port mapped or mapped input output, Port Mapped I/O or I/O Mapped I/O I...

Port Mapped I/O or I/O Mapped I/O I/O devices are mapped into a separate address space. This is generally accomplished by having a different set of signal lines to denote a mem

Adc-arithmetic instruction-microprocessor, ADC: Add with Carry:- This instr...

ADC: Add with Carry:- This instruction performs the similar operation a like ADD instruction, but adds the carry flag bit (which might be set as a result of the previous calculatio

Write a program to find the average of the array , Write a program on the a...

Write a program on the assembly language to do the following: 1- Allocate array with 32bit 100 element 2- Prompt the user to enter the maximum or the upper bound of the rando

Computer organization, write a program using assembly language that print y...

write a program using assembly language that print your name

8237 modes-microprocessor, 8237 modes : Intel 8237 can be set to four d...

8237 modes : Intel 8237 can be set to four different type of style of transfer: 1) Single - One transfer at a time,  it allow processor access to the bus between transfers

Al registre, check the al-register for palindromic number

check the al-register for palindromic number

8086, to separate positive and negative numbers

to separate positive and negative numbers

Program to move contents in memory-machine level programs, Example : Write...

Example : Write a program to move the contents of the memory location 0500H to BX and also to register CX. Add immediate byte 05H to the data residing in memory location, whose ad

Convert from C to 8086 assembly language, Trying to convert small programs ...

Trying to convert small programs from C to 8086 assembly language using emu 8086 emulator. I converted to low level C, but struggling with converting to the Assembly language.

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