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

maximim and minimum mode 8088-microprocessor, Maximim and Minimum mode 808...

Maximim and Minimum mode 8088 system : In the maximum mode, the pin 880 is lastingly high. The functions and timings of other pins of 8088 are exactly similar to 8086. Due to t

Hex , what is the hex value in ax after executing the instructions ax= 1E8...

what is the hex value in ax after executing the instructions ax= 1E8A bx=4080 add al,bl sub ah,bh

Shl, Assume that the registers are initialized to EAX=12345h,EBX =9528h EC...

Assume that the registers are initialized to EAX=12345h,EBX =9528h ECX=1275h,EDX=3001h sub AH,AH sub DH,DH mov DL,AL mov CL,3 shl DX,CL shl AX,1 add DX,AX

Segment registers-microprocessor, Segment Registers The 8086 addresses ...

Segment Registers The 8086 addresses a segmented memory unlike 8085. The complete 1 megabyte memory, which 8086 is capable to address is divided into 16 logical segments.Thusea

Assignment, Write an assembly program that adds the elements in the odd ind...

Write an assembly program that adds the elements in the odd indices of the following array. Use LOOP. What is the final value in the register?

DIV subroutine, I need a division subroutine. Asks for two inputs, then dis...

I need a division subroutine. Asks for two inputs, then displays the inputs and shows the answer with a remainder. Mine isnt displaying the inputs correctly.

Cryptography, Write a program that allows a user to encrypt/decrypt a mess...

Write a program that allows a user to encrypt/decrypt a message using a shift cipher. The user should specify the key and the message. Your program should be able to handle messa

Program that will display a list of the decades , Write an assembly languag...

Write an assembly language program that will display (print) a list of the Decades 2010, 2020, 2030... 2100 to the screen using a while loop.

Write an assembly program to simulate a microwave, 1. The microwave has a c...

1. The microwave has a clock (hh:mm:ss am/pm) and the user should be able to change the clock at any time. 2. For cooking the user should first enter the time. The user can ente

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