Digital Electronics - The 8051 Microcontroller - Discussion

I think that a label is used when you need any jump or loop condition.

Answer is TRUE because label is used for our reference when the code is executed assembler replaces this with the address, which is unique.

Example code:

add a,r1
jnz skip
mov r2,a
skip: mov r2,b

As shown in the above sample program assembler replaces this skip label with the address of the instruction mov r2,b which is unique so label is used to name a single line of code.

A label is a special type of symbols used to represent a textual version of an address in ROM or RAM memory. They are always placed at the beginning of a program line. It is very complicated to call a subroutine or execute some of the jump or branch instructions without them. They are easily used:.

A symbol (label) with some easily recognizable name should be written at the beginning of a program line from which a subroutine starts or where jump should be executed.

It is sufficient to enter the name of label instead of address in the form of 16-bit number in instructions calling a subroutine or jump.

During the process of compiling, the assembler automatically replaces such symbols with appropriate addresses.

What is the assembler ?

Assembler is converts the assembly language into machine code language.