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

What is a signaling protocol, QUESTION (a) How VoIP Works and how VoIP ...

QUESTION (a) How VoIP Works and how VoIP helps today's business? (b) What is a signaling protocol? Explain about SIP components and their key benefits (c) What is IPTV? L

Dataflow modeling for dsp design, Dataflow Modeling for DSP Design The ...

Dataflow Modeling for DSP Design The necessary components in the research of application-specific computer architectures are: 1) a clearly identified set of problems that can b

#title., what is input and output device? explain meaning of input and outp...

what is input and output device? explain meaning of input and output devices

Software, Software Computer cannot be used without a software in...

Software Computer cannot be used without a software in it. It is the software which gives instructions to the hardware of the computer so as to work all devices in tande

What is atm cell, Header contains routing and error control information Pay...

Header contains routing and error control information Payload carries the actual user information, either voice, data or video

Distinguish between s-http and ssl, QUESTION (a) Distinguish between S...

QUESTION (a) Distinguish between S-HTTP and SSL (b) What are the three basic security provided by SSL? (c) Discuss the limitations of SSL (d) State the port number us

Types of computer, types of computer on the basis of shape, size & resource...

types of computer on the basis of shape, size & resources

Education and society, mention the aims of education in present scenario

mention the aims of education in present scenario

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