What Is EQU Instruction?

The EQU instruction

assigns absolute or relocatable values to symbols

. Use it to: Assign single absolute values to symbols. Assign the values of previously defined symbols or expressions to new symbols, thus letting you use different mnemonics for different purposes.

What is the function of EQU assembler directive?

In assembly code, the assembler directive EQU is

used to assign a label to a number

, which can be a literal, a file register number or an individual register bit.

What is equ microprocessor?

The EQU directive is

used to give name to some value or symbol

. Each time the assembler finds the given names in the program, it will replace the name with the value or a symbol. The value can be in the range 0 through 65535 and it can be another Equate declared anywhere above or below.

What is the advantage of using the EQU directive to define a constant value?

Using symbolic constants instead of undescriptive numbers makes

your code more readable and easier to maintain

. The assembler does not allocate data storage when you use either EQU or = . The assembler simply replaces each occurrence of the symbol with the value of the expression.

What are assembler directives explain the function of EQU and start?

Assembler directives are

instructions that direct the assembler to do something

. … This is used to set the program or register address during assembly. For example, ORG 0100h tells the assembler to assemble all subsequent code starting at address 0100h.

What EQU means?

The Latin root word equ means

“equal

.” This Latin root is the word origin of a good number of English vocabulary words, including adequate, equator, and equality. The Latin root word equ is easily recalled through the word equation, for both sides of an equation are, by definition, “equal” to one another!

What do you mean by EQU and $-?

The action of EQU is

to define the given label name to the value of its (only) operand

. This definition is absolute, and cannot change later. So, for example, message db ‘hello, world’ msglen equ $-message. defines msglen to be the constant 12. msglen may not then be redefined later.

What does EQU mean in assembly?

The EQU directive

only tells the assembler to substitute a value for a symbol or label

, and doesn’t involve any type of ROM or RAM. EQU directives are typically placed at the beginning of an assembly program.

What is the difference between procedure and macro?

The main difference between Macro and Procedure is that the Macro is used for a small number of instructions;

less than ten instructions

, but Procedure is used for a large number of instructions; higher than ten instructions.

Why are assembler directives required?

The assembler directives control organization of the program and

provide necessary information to the assembler to understand assembly language programs to generate machine codes

. They indicate how an operand or a section of program is to be processed by the assembler.

What is the meaning of Masm?

The

Microsoft Macro Assembler

(MASM) is an x86 assembler that uses the Intel syntax for MS-DOS and Microsoft Windows.

Which directive is used to define constants?

The %define Directive

The above code replaces PTR by [EBP+4]. This directive also allows redefinition and it is case-sensitive.

What is Ltorg statement?

Use the LTORG instruction so

that the assembler can collect and assemble literals into a literal pool

. A literal pool contains the literals you specify in a source module either after the preceding LTORG instruction, or after the beginning of the source module.

What is difference between assembler directives and instructions?

Answer: Assembler instruction generates machine code, thus contributes towards the size of the program .

Assembler directive does not create any machine code

,thus does not contribute to program size.It directs the assembler to perform certain actions during assembly phase.

What are the different types of assemblers used?

• 6502 assemblers.
• 680×0 assemblers.
• ARM assemblers.
• IBM mainframe assemblers.
• POWER, PowerPC, and Power ISA assemblers.
• x86 assemblers.
• x86-64 assemblers.
• Z80 assemblers.

What are arm directives?