What Value Do Registers Start At In Mips

MIPS assembly language only refers to the assembly language of the MIPS processor. The term MIPS is an acronym for Microprocessor without Interlocked Pipeline Stages. It is a reduced-instruction set up architecture developed by an organization called MIPS Technologies.

The MIPS assembly linguistic communication is a very useful language to learn considering many embedded systems run on the MIPS processor. Knowing how to code in this linguistic communication brings a deeper understanding of how these systems operate on a lower level.

Before you kickoff coding in the MIPS associates language

Before yous outset churning out MIPS assembly linguistic communication code, y'all need to kickoff obtain a very good Integrated Development Surroundings. That tin can help to compile and execute your MIPS assembly language code. The software that I would recommend this purpose is the MARS (MIPS Assembler and Runtime Simulator). You can find information technology hands on Google, and download information technology.

Introduction to the MIPS compages

Data Types

All the instructions in MIPS are 32 $.25.
A byte in the MIPS compages represents 8 $.25; a halfword represents 2 bytes (sixteen bits) and a word represents four bytes (32 $.25).
Each character used in the MIPS architecture requires 1 byte of storage. Each integer used requires 4 bytes of storage.

Literals
In the MIPS architecture, literals correspond all numbers (east.chiliad. v), characters enclosed in single quotes (east.g. 'g') and strings enclosed in double quotes (due east.thou. "Deadpool").

Registers
MIPS architecture uses 32 general-purpose registers. Each register in this architecture is preceded by '$' in the associates linguistic communication education. You can address these registers in 1 of two means. Either utilize the register's number (that is, from $0 to $31), or the register's proper noun (for example, $t1).

General structure of a plan created using the MIPS assembly language

A typical program created using the MIPS associates language has two primary parts. They are the data declaration section of the plan and the code department of the program.

Information proclamation section of a MIPS associates language program

The data declaration section of the program is the part of the program identified with the assembler directive .data. This is the part of the programme in which all the variables to be used in the program are created and defined. It is also the part of the programme where storage is allocated in the main memory (RAM).

The MIPS associates language program declares variables as follows:

          name:          	.storage_type          	value(due south)

The "name" refers to the name of the variable beingness created. The "storage_type" refers to the blazon of data that the variable is meant to store. The "value(due south)" refers to the information to exist stored in the variable being created. The post-obit MIPS assembly linguistic communication syntax creates a single integer variable with the initial value of v:

          .data     var1:   	 .word   	 5

Code section of the MIPS assembly language program

The code section of the program is the part of the plan in which the instructions to be executed by the program are written. It is placed in the section of the plan identified with the assembler directive .text. The starting indicate for the code section of the plan is marked with the label "main" and the ending point for the code section of the programme is marked with an exit organisation call. This section of a MIPS assembly language program typically involves the manipulation of registers and the performance of arithmetic operations.

Manipulation of registers

In the manipulation of registers, the MIPS associates language utilizes the concepts of load, and indirect or indexed addressing.

In the concept of load addressing, the Random-Admission Retentivity address of a variable in the MIPS associates language program is copied and stored in a temporary register. For instance, to copy the address of a variable called "var1" into the temporary register $t0, the post-obit MIPS assembly language syntax is required:

          la $t0, var1

In the concept of indirect addressing, the value stored in a particular Random-Admission Memory accost is copied into a temporary register. For example, use the following MIPS assembly language syntax to copy an integer value stored in the Random-Access Memory address of register $t0 into register $t2

          lw $t2, ($t0)

In the concept of indexed addressing, the Random-Access Retentivity address of a register tin be offset by a specified value to obtain a value stored in another Random-Access Memory address. For instance, to obtain the value stored in a Random-Access Memory address which is iv addresses away from the Random-Access Retentivity address of the register $t0, and shop that value in register $t2, the following MIPS assembly language syntax is required:
lw $t2, 4($t0)

Performance of arithmetic operations

In the MIPS assembly language, virtually arithmetics operations use three operands, and all these operands are registers. The size of each operand is a discussion, and the general format for performing arithmetic operations in the MIPS associates language is shown every bit follows:

          arithmetic_operation storage_register, first_operand, second_operand

Where "arithmetic_operation" refers to the arithmetic functioning that is being performed, "storage_register" refers to the register that is used to shop the result of the arithmetic computation; "first_operand" refers to the register that contains the first operand of the arithmetics operation, and "second_operand" refers to the annals that contains the second operand of the arithmetics operation.

The nigh mutual arithmetic operations implemented in the MIPS assembly linguistic communication are addition, subtraction, multiplication and sectionalisation. The following table represents the various arithmetic operations that have been listed and how they are represented in the MIPS assembly language:

Creating a simple MIPS assembly language program

In this post, we create a uncomplicated programme that can obtain two different numbers from a user and perform the arithmetic operations of addition, subtraction and multiplication on those two numbers.

The start matter to do when creating this program is to define the variables that are to be used to store the strings used in the program.

#This is a uncomplicated programme to take two numbers from the user and perform
#bones arithmetic functions such as addition, subtraction and multiplication with them

#Programme flow:
#1. Print statements to ask the user to enter the two different numbers
#2. Store the two numbers in different registers and print the 'menu' of arithmetics instructions to the user
#iii. Based on the choice made by the user, create co-operative structures to perform the commands and impress the result
#4. Exit the program

          .data         prompt1:    .asciiz   	 "Enter the offset number: "     prompt2:    .asciiz   	 "Enter the second number: "     menu:   	 .asciiz   	 "Enter the number associated with the functioning you want performed: i => add, ii => subtract or three => multiply: "     resultText:    .asciiz   	 "Your final result is: "

The second thing to practice is to pre-load the integer values representing the various instructions to be performed by the plan into their respective registers for storage.

          .text .globl main principal:     #The following cake of code is to pre-load the integer values representing the various instructions into registers for storage     li $t3, i    #This is to load the immediate value of one into the temporary register $t3     li $t4, ii    #This is to load the immediate value of 2 into the temporary annals $t4     li $t5, iii    #This is to load the immediate value of 3 into the temporary register $t5

And then, print out the instructions that crave the user to input the two numbers that they would similar to perform the arithmetic operations on.

          #request the user to provide the get-go number     li $v0, 4     #command for press a cord     la $a0, prompt1 #loading the string to print into the argument to enable printing     syscall   	 #executing the command                #the next block of code is for reading the first number provided past the user     li $v0, 5    #command for reading an integer     syscall   	 #executing the command for reading an integer     move $t0, $v0     #moving the number read from the user input into the temporary register $t0          #request the user to provide the second number     li $v0, four    #control for printing a string     la $a0, prompt2    #loading the string into the argument to enable press     syscall   	 #executing the command               #reading the second number to be provided to the user     li $v0, 5    #command to read the number  provided past the user     syscall   	 #executing the command for reading an integer     move $t1, $v0    #moving the number read from the user input into the temporary register $t1

The next step is to impress out the commands the user can perform on the 2 numbers that have been provided. This is to enable the user to select a course of activeness.

#the side by side cake of code is to print all of the commands that the user can take with regards to the #2 numbers that he or she has provided

          li $v0, 4    #command for press a cord     la $a0, menu    #loading the string into the argument to enable printing     syscall   	 #executing the command            #the adjacent block of code is to read the number provided by the user     li $v0, 5    #command for reading an integer     syscall   	 #executing the command     move $t2, $v0    #this command is to move the integer provided into the temporary register $t2

At this point, you demand to create control structures that determine which instructions are to be executed based on the command issued by the user.

The following lines of code determine what should take place depending on the integer value # that was provided by the user

          beq $t2,$t3,addProcess    #Branch to 'addProcess' if $t2 = $t3     beq $t2,$t4,subtractProcess #Branch to 'subtractProcess' if $t2 = $t4     beq $t2,$t5,multiplyProcess #Co-operative to 'multiplyProcess' if $t2 = $t5

The next code instructs adding the two numbers provided.

          addProcess:     add $t6,$t0,$t1    #this adds the values stored in $t0 and $t1 and assigns them to the     temporary register $t6          #The following line of code is to impress the results of the ciphering above     li $v0,4    #this is the command for printing a string     la $a0,resultText    #this loads the string to impress into the argument $a0 for printing     syscall   	 #executes the command          #the post-obit line of lawmaking prints out the issue of the addition computation     li $v0,1     la $a0, ($t6)     syscall          li $v0,ten #This is to stop the program

This is an example of code for instructions to subtract the ii numbers provided.

          subtractProcess:     sub $t6,$t0,$t1 #this adds the values stored in $t0 and $t1 and assigns them to the temporary annals $t6     li $v0,4    #this is the command for press a string     la $a0,resultText    #this loads the cord to print into the argument $a0 for printing     syscall   	 #executes the command          #the following line of code prints out the result of the addition computation     li $v0,1     la $a0, ($t6)     syscall          li $v0,10 #This is to finish the program

This code is for instructions to multiply the two numbers provided.

          multiplyProcess:     mul $t6,$t0,$t1 #this adds the values stored in $t0 and $t1 and assigns them to the temporary register $t6     li $v0,4    #this is the command for printing a string     la $a0,resultText    #this loads the string to print into the argument $a0 for press     syscall   	 #executes the command          #the following line of code prints out the result of the addition computation     li $v0,ane     la $a0, ($t6)     syscall          li $v0,10 #This is to stop the programme

When you are washed implementing the code shown to a higher place, just compile your program and run information technology. Congratulations! Y'all have implemented your first MIPS assembly language program. 😊

Boosted references to larn more about MIPS assembly language syntax:
https://chortle.ccsu.edu/AssemblyTutorial/index.html

Decision

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I hope that in this tutorial you have received all the basic skills you need to help yous to create a very simple MIPS associates linguistic communication program.