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

Input - output services, Input/Output Services:   Every operating syst...

Input/Output Services:   Every operating system, large or small, provides input/output services for each device in the system. The operating system includes I/O device driver

Exercise 2: Green cloud computing, Ask questioMost part of power consumptio...

Ask questioMost part of power consumption in data centers comes from computation processing, disk storage, network and cooling systems. Nowadays, there are new technologies and met

Flow decomposition technique to list the cycles, QUESTION (a) Consider ...

QUESTION (a) Consider the graph below, use the Flow Decomposition technique to list the cycles and paths produced.                                                (b) Pr

Software design, Ineed help to do my homework which is for designing of req...

Ineed help to do my homework which is for designing of requirenments.

Outdoor patient department features - receptionist module, Outdoor Patient...

Outdoor Patient Department (OPD) Features The following modules can be developed for various areas and workers. A receptionist Module Receptionist updates all bas

Definition of User-Level Thread?, User-level threads apply in user-level li...

User-level threads apply in user-level libraries, before via systems calls, so thread switching does not require to call operating system and to cause interrupt to the kernel. Actu

Keystroke logger and data-stealing, Keystroke logger and Data-stealing: ...

Keystroke logger and Data-stealing: Keystroke loggers: This is a program, once installed on the system, which intercepts the keys when entering the password or the Credit Ca

Algorithms, write algotithm and flow chart for largest of 3 numbers

write algotithm and flow chart for largest of 3 numbers

Depth first search-artificial intelligence, Depth First Search-Artificial i...

Depth First Search-Artificial intelligence: Depth first search is  similar to breadth first, except that things are added to the top of the plan rather than the bottom. In our

Online searching, Online Searching: The real difference between manual...

Online Searching: The real difference between manual searching and online searching lies, according to William A. Katz, in the mechanics and the jargon of the latter. However,

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