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

Read only memory (rom), Read only memory (rom): The problem with RAM is...

Read only memory (rom): The problem with RAM is that its memory is volatile, i.e. it loses all its data when the power supply is removed.  A non-volatile memory is a permanent

Modeling historical data, Given the scenario below, construct a conceptual ...

Given the scenario below, construct a conceptual model. The Seville, Spain soccer association is renovating their soccer arena. They are adding luxury boxes that will be offered to

Analogue and digital signals, Analogue and digital signals: Analogue (c...

Analogue and digital signals: Analogue (continuous) information is made available in virtually all aircraft equipment.  Figure 1 shows the analogue signal created by a variable

Data communications, Data communication as a need developed in the 1960s wi...

Data communication as a need developed in the 1960s with the interconnection of peripheral devices to mainframe computers. Within the immediate vicinity of the mainframe computer t

Protocol, what protocol is used by DNS name server

what protocol is used by DNS name server

Date mining, I have assignment in Date mning can you help me

I have assignment in Date mning can you help me

System software, note on high level language and low level language

note on high level language and low level language

Ricochet wireless data network, The Internet is replete with great success ...

The Internet is replete with great success stories and sad failures. While it is always nice to hear about the successes, more can probably be learned from the failures. In this ca

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