Loading instructions, Basic Computer Science

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.
Posted Date: 5/4/2012 4:29:00 AM | Location : United States







Related Discussions:- Loading instructions, Assignment Help, Ask Question on Loading instructions, Get Answer, Expert's Help, Loading instructions Discussions

Write discussion on Loading instructions
Your posts are moderated
Related Questions
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

What are advantages of totem pole over passive pull up circuit ?

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

classify computer system according to capacity. how they are different from computer according to the classification of technology.provide the comparative study also.

implement your own hashset

write advantages and disadvantages of private and public network


draw the e r diagram for irctc rail ticket reservation online

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

Question 1 With an example, illustrate the concept of extern variable Question 2 What is the difference between pointer variable and simple variable? Question 3 Give the