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

How should an ideal hospital software be? , How Should an Ideal Software be...

How Should an Ideal Software be?  It should be easy to operate, with minimal training of nursing personnel.   Should be reliable, and thoroughly tested in various nur

Write a note on modems, Question 1 Write a note on modems Question ...

Question 1 Write a note on modems Question 2 What are the Safe Chatting Rules Question 3 Explain three basic kinds of hypertext links Question 4 Write a no

Object oriented programming, Write a method called Grade that takes a numer...

Write a method called Grade that takes a numeric score and returns a letter grade. Use the rule that 90 to100 is an A, 80 to 89 a B, 60 to 79 is a C, 45 to 59 is a D, and less th

Printer output, Printer output : Consider what is required here. ...

Printer output : Consider what is required here. Do you just require management information on the one hand or camera copy for reprographic purposes? Inkjet Very quiet. C

Explain the functions of alu, Question 1 Write down the Booth's Multiplica...

Question 1 Write down the Booth's Multiplication Algorithm. Justify the Booth's Multiplication Algorithm Question 2 Explain the functions of ALU Question 3 Define the term ins

Memory access, Memory access: The use of semi-conductor memory elements...

Memory access: The use of semi-conductor memory elements (bistables) has been made possible by the use of large scale integrated circuits (LSI) which provide reliability, ease

Convert string to super ascii, A string S is said to be "Super ASCII", if i...

A string S is said to be "Super ASCII", if it contains the character frequency equal to their ascii values. String will contain only lower case alphabets (''''''''a''''''''-'''''''

Theory of computation, If L is a regular language show that L U {a} is regu...

If L is a regular language show that L U {a} is regular

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