💾 Archived View for gem.sdf.org › s.kaplan › cheatsheets › programming-languages › assembly.md captured on 2024-03-21 at 15:45:21.

View Raw

More Information

⬅️ Previous capture (2023-09-28)

-=-=-=-=-=-=-

# Assembly Cheatsheet

## Overview of unique features

- Low-level programming language
- Direct interaction with hardware
- No high-level abstractions
- Limited built-in functions
- Requires knowledge of CPU architecture

## Variables

Assembly does not have variables in the same sense as high-level programming languages. Instead, it uses registers to store data.

; Move a value into a register

mov eax, 42

; Move a value from one register to another

mov ebx, eax


## Functions

Assembly does not have functions in the same sense as high-level programming languages. Instead, it uses subroutines to perform specific tasks.

; Define a subroutine

mySubroutine:

; do something

ret

; Call a subroutine

call mySubroutine


## Loops

Assembly uses jump instructions to create loops.

; Define a loop

myLoop:

; do something

jmp myLoop


## Conditionals

Assembly uses conditional jump instructions to create if-else statements.

; Define an if-else statement

cmp eax, ebx

jg greaterThan

jmp lessThan

greaterThan:

; do something

jmp endIf

lessThan:

; do something else

jmp endIf

endIf:


## Interacting with hardware

Assembly uses specific instructions to interact with hardware.

; Set up a digital pin

mov al, 0xFF

out 0x02, al

; Turn on and off an LED

mov al, 0x01

out 0x02, al

mov al, 0x00

out 0x02, al


## Resources

- [x86 Assembly documentation](https://www.cs.virginia.edu/~evans/cs216/guides/x86.html)
- [NASM tutorial](https://cs.lmu.edu/~ray/notes/nasmtutorial/)
- [Assembly language forum](https://forum.nasm.us/) for community support and troubleshooting.