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

Javascript, Need help with javascript sb.append questions

Need help with javascript sb.append questions

Identify important elements of multimedia, Problem 1 Identify important...

Problem 1 Identify important elements of Multimedia and explain with example. Stating important elements of Multimedia with example of each Problem 2 Explain a

Operating systems, Consider the state transition diagram of Figure 3.9b. Su...

Consider the state transition diagram of Figure 3.9b. Suppose that it is time for the OS to dispatch a process and that there are processes in both the Ready state and the Ready/Su

Write a long note on computer languages, Question 1 Explain the importan...

Question 1 Explain the importance of graphics in multimedia. What are few of the tips to keep in mind while using graphics for the web? Question 2 Write a long note on co

Circuit switching and , Circuit Switching: Many switching techniques a...

Circuit Switching: Many switching techniques are in use. One of them is line or circuit switching in which a communications path is actually established before the message is

MIS, information system providors

information system providors

Comp 100, I have an account in my www.itlab.com and i have a test and it s...

I have an account in my www.itlab.com and i have a test and it should do tonight, so do you have any one to help me and do this test and it is about excel

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,

Artificial intelligence-environments, Artificial Intelligence-Environments ...

Artificial Intelligence-Environments   We have seen that intelligent agents should take into description sure information when   choosing  a rational act,  including inform

Communication channels, COMMUNICATION CHANNELS: A wire pair connecting...

COMMUNICATION CHANNELS: A wire pair connecting two telephones is the simplest circuit, allowing communication in both directions. Other channels include coaxial cables, optica

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