This project contains three exercises demonstrating the interface between C and Assembly language. Each exercise includes a C program and an Assembly routine to perform specific tasks, showcasing how C and Assembly can work together.

This exercise demonstrates a simple function call from C to Assembly that prints a message.

#include <stdio.h> int main() { extern int imprimo(); int y; printf("Programa que hace el llamado de la función imprime\n"); imprimo(); return 0; }

This C code declares an external function imprimo and calls it to print a message.

global imprimo extern printf section .data  msg db "hola mundo!!", 0 section .text imprimo:  push dword msg  call printf  add esp, 4  ret

This Assembly code defines the imprimo function, which prints "hola mundo!!" using the printf function from the C standard library.

This exercise shows how to pass parameters from C to Assembly and return the result back to C.

#include <stdio.h> extern int suma(int v1, int v2); int main() { int v1, v2, sum; printf("Dame un dato para sumar\n"); scanf("%d", &v1); printf("Dame otro numero para sumar\n"); scanf("%d", &v2); sum = suma(v1, v2); printf("El resultado de la suma es = %d\n", sum); return 0; }

This C code reads two integers from the user, calls the suma function, and prints the result.

global suma suma:  push dword ebp  mov ebp, esp  mov eax, [ebp + 8]  mov edx, [ebp + 12]  add eax, edx  pop dword ebp  ret

This Assembly code defines the suma function, which takes two integers as parameters, adds them, and returns the result.

This exercise implements the Collatz conjecture, using a combination of C and Assembly to process the sequence.

#include <stdio.h> extern int half(int x); int main() { int count, x, y; count = 0; printf("Entra un número: "); scanf("%d", &x); while (x != 1) { count++; y = half(x); printf("\nDevuelve %d\n", y); if (y != 0) x = y; else x = x * 3 + 1; printf("\nX = %d\n", x); } printf("\nHay %d iteracciones.\n\n", count); return 0; }

This C code reads an integer from the user, repeatedly applies the Collatz function, and prints the number of iterations.

global half half:  push ecx  mov ecx, [esp + 8]  mov eax, 0 agn:  inc eax  sub ecx, 2  jg agn  jz dun  mov eax, 0 dun:  pop ecx  ret

This Assembly code defines the half function, which performs integer division by 2 and returns the result.

1. Compilation: Each C file can be compiled with the corresponding Assembly file using gcc and nasm.

 gcc -o holaxd holaxd.c imp.o nasm -f elf32 imp.asm gcc -o variable variable.c pasoparam.o nasm -f elf32 pasoparam.asm gcc -o collatz collatz.c half.o nasm -f elf32 half.asm

2. Execution: Run the compiled programs to see the output of the C-Assembly interactions.

 ./holaxd ./variable ./collatz