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

Arrays and strings, This is a C file. 1. The program starts by printing you...

This is a C file. 1. The program starts by printing your name with an end sign ">". For example, "NAME >"; 2. Then, you can type in a string. If the string is not "vi xxx", you pri

Python Strings and Python Lists, Python Strings: Strings in Python are rec...

Python Strings: Strings in Python are recognized as an adjacent set of characters in among quotation marks. Python permits for either pairs of single or double quotes. Subsets of s

Explain the important concepts of modern cpu, Question 1 Explain the impor...

Question 1 Explain the important concepts of modern CPU CISC vs. RISC CPUs Circuit Size and Die Size Processor Speed Processor Cooling System Clocks Architect

Analogue to digital converter, Analogue to digital converter: In an ADC...

Analogue to digital converter: In an ADC a range of input values must correspond to a unique digital word.  The type of code used depends on the system but here only binary cod

Memory hierarchy, Memory hierarchy: There is another type of high spee...

Memory hierarchy: There is another type of high speed memory, known as Cache memory, which is used to increase the speed of processing by making current programs and data avai

How to create basic assembler program?, The primary step is to start the De...

The primary step is to start the Debug; this step only consists of typing debug [Enter] on the operative system on time. the "a" (assemble) command is used To assemble a program on

The elif Statement, The elif statement permits you to check multiple expres...

The elif statement permits you to check multiple expressions for truth value and execute a block of code the moment one of the conditions estimates to true. similar to the else, th

flow chart for online placement, Create systems flow chart and state trani...

Create systems flow chart and state tranistion diagram for online placement and consultancy

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