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

Optical mark recognition, Optical Mark Recognition (OMR): OMR is the s...

Optical Mark Recognition (OMR): OMR is the scanning of paper to detect the presence or absence of a mark in a predetermined position. Now days, it is used as an input device f

Describe any five requirements of clustering in data mining, Question 1...

Question 1 What is data mining? What are the major issues in data mining? Explain 2 What is meant by data reduction? Explain any three techniques of data reduction 3 Define a b

Input devices of a digital computer, Input devices of a digital computer: ...

Input devices of a digital computer: Input devices are used to read the instructions and data to be processed and output devices display the results obtained after executing t

Readymade versus custom-made software, READYMADE VERSUS CUSTOM-MADE SOFTWAR...

READYMADE VERSUS CUSTOM-MADE SOFTWARE Nursing care software can be in two forms. Software can be custom-made with the help of a computer programmer, suited for a client with v

Buses, BUSES It can be seen from Figure 4 that there are three buses ...

BUSES It can be seen from Figure 4 that there are three buses - the data bus, the address bus, and the control bus. Each bus consists of a group of parallel wires. The da

Write the function pop in c, QUESTION (a) Convert each of the following...

QUESTION (a) Convert each of the following expressions to prefix and postfix. (i) (A+B)*(C+D) (ii) A-B/(C*D^E) (^ denotes exponentiation) (b) The following algorithm c

2. What benefits can a company gain by managing its , 2. What benefits can ...

2. What benefits can a company gain by managing its own information infrastructure and services?

Assembly language, Assembly language : Assembly language is a low level...

Assembly language : Assembly language is a low level programming language similar to machine language, but far easier to write and understand because machine language binary in

CAI, what is CAI? explain its pitfalls.

what is CAI? explain its pitfalls.

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