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

Computational physiology, Estimate the mean deflection of the QRS complex i...

Estimate the mean deflection of the QRS complex in each of the six standard leads (I, II, III, aVR, aVL, aVF) in Figure 1 and then estimate the mean heart vector for the normal hea

List two i/o virtualization methods, Question 1 List two I/O virtualizatio...

Question 1 List two I/O virtualization methods. Based on different features compare these two methods Question 2 Discuss three areas considered by organizations to secure the

Wide area networks and metropolitan area networks, Metropolitan Area Networ...

Metropolitan Area Networks : These type of networks generally cover specific metropolitan area and provide to them all the services.  Wide Area Networks (WANs): Wide Are

Bootstrap loader, Bootstrap loader: The critical programs are loaded i...

Bootstrap loader: The critical programs are loaded into memory by the bootstrap loader at start-up time and will remain resident as long as the computer is running. The bootst

College management system project, E-R diagram and details for college mana...

E-R diagram and details for college management system

Multiprogramming, Multiprogramming Multiprogramming means capability of...

Multiprogramming Multiprogramming means capability of several programs to simultaneously occupy a portion of the computer’s memory and compete for central processor time. Th

Computer architecture, Consider a CPU that implements two parallel fetch-ex...

Consider a CPU that implements two parallel fetch-execute pipelines for superscalar processing. Show the performance improvement over scalar pipeline processing and no-pipeline pro

What is meant by clock skew and clock drift among clocks, QUESTION (a) ...

QUESTION (a) Describe what is meant by Clock Skew and Clock Drift among clocks in a distributed system. (b) A clock is reading 08:25:46.0 (hr:min:sec) when it is discovered

What is a Process and process mangemen in operating system? , A process is ...

A process is a chronological program in execution. The constituents of a process are the following: • The object program to be executed ( described the program text in UNIX) • Th

CAI, EXPLAIN CAI? AND ITS PITFALLS

EXPLAIN CAI? AND 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