Assembly language is a low-level programming language that is very close to machine language (i.e., the binary code we saw in the previous entry).
Unlike high-level languages like C++ or Java, which are easier for humans to understand, assembly language is designed to be easier for the processor to understand.
Assembly language is a programming language that uses mnemonics to represent the instructions that will be executed by the processor. These mnemonics are translated by the assembler into their equivalent binary code.
For example, the ADD instruction in assembly represents an addition operation in the processor. The assembler converts this instruction into its equivalent binary code so the processor can execute it.
An example of a program in Assembly language would be:
section .data
message db 'Hello, world!', 0
section .text
global _start
_start:
; Write the message to the console
mov eax, 4 ; System call code to write to screen
mov ebx, 1 ; Standard output file descriptor (stdout)
mov ecx, message ; Address of the message to print
mov edx, 13 ; Length of the message
int 0x80 ; System interrupt to perform the call
; Exit the program
mov eax, 1 ; System call code to exit
xor ebx, ebx ; Return value (0)
int 0x80 ; System interrupt to perform the call
As we can see, as a programming language it is still quite horrible. But it already has some of the points we will see in programming languages such as:
- Blocks
- Variables
- Comments
- Entry and exit points
Translating Assembly to Machine Code
The process of translating Assembly language into binary code is performed through the assembly process (it is precisely this process that gives the programming language its name).
The assembly process uses a table of instructions and their equivalent opcodes to convert the instructions written in Assembly into binary code.
For example, if during assembly it encounters the ADD instruction in the source code, it will look up the corresponding addition operation in binary code in the instruction table and generate the necessary binary code for the processor to execute that operation.
Assembly language is a very low-level programming language used to program systems that require precise control over processor resources.
Its relationship with binary code is very close, as it uses mnemonics to represent the instructions that are translated into binary code. In fact, the assembly process is a simple process, basically a direct translation using tables.
Assembly language is not frequently used today. But it is still used to program systems where precise control over processor resources is needed, such as in operating systems, device drivers, and real-time software.
