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

Introduction to computer, Computer: People call a lot of things, compu...

Computer: People call a lot of things, computers. Some of them are cheap, but can only process numerical information. Such devices would better be described as 'calculators' r

The terms ''row-major order'' and ''column-major order", What is meant by t...

What is meant by the terms 'row-major order' and 'column-major order'? Ans: (i) Storing the array column by column is called as column-major order and storing the array row by

Explain digital multiplexers, Problem 1 Perform the following conversio...

Problem 1 Perform the following conversion a. (ABE) 16 =() 2 b. (101011) 2 =() 10 2 Explain how full adder adds three bits 3 Explain digital multiplexers

Explain the process of fetching a word from the memory, Question 1 Explain...

Question 1 Explain the functional units of a basic computer with a neat diagram Question 2 Explain how you can get 1's complement of a given binary number? Also explain 1'

Counters and registers, design a synchronous, recycling, MOD-12 counter wit...

design a synchronous, recycling, MOD-12 counter with D FF''s. Use the states 0000 through 1011 in the counter.

Comp 100, I have an account in my www.itlab.com and i have a test and it s...

I have an account in my www.itlab.com and i have a test and it should do tonight, so do you have any one to help me and do this test and it is about excel

Components of a computer, COMPONENTS OF A COMPUTER: We use a computing...

COMPONENTS OF A COMPUTER: We use a computing system basically to feed in some data that is processed by the computer and some information is generated as a result.. For this w

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