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

What is collaboration, Question 1 What is Collaboration? Write down the ob...

Question 1 What is Collaboration? Write down the objectives of collaboration Question 2 What is proxy server? Write down the reasons for using proxy server Question

Theory of computation, I define a restricted form of TMs M as follows. Give...

I define a restricted form of TMs M as follows. Given any input x on the tape of M, the initial portion of the tape that holds x is read-only and one-way. That is, M cannot write o

Define stocktaking, QUESTION (i) Define each of the following terms: ...

QUESTION (i) Define each of the following terms: a) Book trade catalogue b) Stocktaking c) Ephemera d) Contracting out e) Special library (ii) Discuss the adv

Poset , 1. (40 points) Add a course drop method to the system that you impl...

1. (40 points) Add a course drop method to the system that you implemented in Problem Set 1. Modularize your new implementation properly. For any new methods that you introduce: 1.

Breadth first search - artificial intelligence, Breadth First Search - arti...

Breadth First Search - artificial intelligence: Given a set of operators o1, ..., on in a breadth primary search, every time a new state s is reached, an action for every  oper

Description of external hardware interruptions, External interruptions are...

External interruptions are produced by peripheral devices, for example keyboards, printers, communication cards, etc. They are also produced by coprocessors. It is not achievable t

Graphical user interface and arrays, In this program, you are going to writ...

In this program, you are going to write a program for playing the game of Hangman. In this game, the computer will pick a word and display a sequence of blanks to be filled in; one

Working principle of master slave j-k flip flop, Problem 1. Obtain the ...

Problem 1. Obtain the set of prime implicants for f = Σ m (0,1,6,7,8,9,13,14,15) . Obtaining the set of prime implicants: 2. Draw the logic diagram of a divide by

Write a schema for the operation of ending a game, QUESTION 1 We need ...

QUESTION 1 We need to write Z specifications to record the information about passengers on board an aircraft. Here you are required to produce the specifications using appropr

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