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

Briefly explain html and xml, Question 1 Briefly explain principles of eff...

Question 1 Briefly explain principles of effective navigation Question 2 Explain the terms URI and URL. Why should you use Relative URI? Question 3 What are the di

What are the Software interruptions, Software interruptions can be thoroug...

Software interruptions can be thoroughly activated by the assembler invoking the number of the preferred interruption with the INT instruction. The use of interruptions aids us in

Define Program formation process, For the formation of a program it is nece...

For the formation of a program it is necessary to follow five steps: Design of the algorithm, stage the problem to be solved is reputable and the best solution is proposed, creatin

Magnetic media, what are the five precautions to be observed when handling ...

what are the five precautions to be observed when handling magnetic media?

Transmission control protocol, The TCP/IP networking protocol suite is so b...

The TCP/IP networking protocol suite is so basically named for two of its very most and important protocols: Transmission Control Protocol online tutoring Indication Manage

Knowledge of the environment of ai system, Knowledge of the Environment ...

Knowledge of the Environment We must distinguish between knowledge an agent receives through it's sensors and knowledge about the world from which the input comes. Knowledge a

C programming program, I wrote a program that adds up 5x5 matrices by colum...

I wrote a program that adds up 5x5 matrices by column and row. Now i have to use pointers to rewrite the same code how would do that

Access time - storage devices, Access time: Access time: This is the t...

Access time: Access time: This is the time required to locate and retrieve stored data from the storage unit in response to a program instruction. That is the time interval be

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