Loading instructions, Basic Computer Science

Assignment Help:
They are particular register instructions. They are used to load bytes or sequences of bytes onto a register.
LODS (LODSB) (LODSW)
LAHF
LDS
LEA
LES
LODS (LODSB) (LODSW) INSTRUCTION
Goal: To load sequences of a byte or a word into the accumulator.
Syntax:
LODS
This instruction takes the sequence found on the address specified by SI, loads it to the AL (or AX) register and adds or subtracts , depending on the state of DF, to SI if it is a bytes transfer or if it is a words transfer.
MOV SI, OFFSET VAR1
LODS
The first line loads the VAR1 address on SI and the second line receives the content of that locality to the AL register.
• The LODSB and LODSW commands are used likewise, the first one loads a byte and the second one a word (it uses the whole AX register).
LAHF INSTRUCTION
Goal: It transfers the full content of the flags to the AH register.
Syntax:
LAHF
This instruction is helpful to make sure the state of the flags through the execution of our program.
LDS INSTRUCTION
Goal: used to load the register of the data segment
Syntax:
LDS destiny, source
The source operator must be a dual word in memory. The word related with the largest address is transferred to DS, in other words it is taken as the segment address. The word associated with the lesser address is the displacement address and it is deposited in the register indicated as destiny.
LEA INSTRUCTION
Goal: To load the address of the source operator
Syntax:
LEA destiny, source
The source operator must be situated in memory, and its displacement is placed on the index register or specified pointer in destiny.

Related Discussions:- Loading instructions

Qbasic, write a program of circle of any colour

write a program of circle of any colour

C program , write a c program for below question

write a c program for below question

Boolean expression, Problem 1. Obtain the truth table and a Boolean exp...

Problem 1. Obtain the truth table and a Boolean expression for the following conditions: x is 0 if any two of the three variables are 1. x is 1 for all other conditions.

Machines which exhibit intelligent nature, Machines which exhibit intellige...

Machines which exhibit intelligent nature Machines in this case could easily be personal computers, or they could be robots with embedded systems, or a combination of both. Wh

Finite Automata, (S**)*=S*** is this set bigger than S*??

(S**)*=S*** is this set bigger than S*??

What is the structure of a global.asax file in asp.net, Question (a) De...

Question (a) Describe the following built-in functions and illustrate each using simple examples. Specify every possible parameters where required Replace() StrComp()

Problem - programming language, Problem - programming language: A Prob...

Problem - programming language: A Problem is to carry out a particular task. For solving the problem, some input has to be given to the system. The system will process or mani

Computer architecture, #formular for calculating speed up factor fo super s...

#formular for calculating speed up factor fo super scalar architecture, super pipeline architecture and VLIW with m different functional units.

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