/**
 ******************************************************************************
 * @file           : main.c
 * @author         : Auto-generated by STM32CubeIDE
 * @brief          : Main program body
 ******************************************************************************
 * @attention
 *
 * Copyright (c) 2026 STMicroelectronics.
 * All rights reserved.
 *
 * This software is licensed under terms that can be found in the LICENSE file
 * in the root directory of this software component.
 * If no LICENSE file comes with this software, it is provided AS-IS.
 *
 ******************************************************************************
 */

#include <stdint.h>
#include "stm32f103xb.h"

#if !defined(__SOFT_FP__) && defined(__ARM_FP)
  #warning "FPU is not initialized, but the project is compiling for an FPU. Please initialize the FPU before use."
#endif


//----------Ejercicio 2----------
int main(void) {
    // Habilitar Reloj Puerto A (bit 2) y Puerto C (bit 4)
    RCC->APB2ENR |= (1 << 2) | (1 << 4);

    // Configurar PC13 como Salida Push-Pull 2MHz
    GPIOC->CRH &= ~(0xF << 20); // Limpiar bits 20-23
    GPIOC->CRH |= (1 << 21);    // MODE13 = 10 (2MHz)

    // Configurar PA0 como Entrada con Pull-down
    // Bits 0-1 (MODE), 2-3 (CNF)
    GPIOA->CRL &= ~(0xF << 0);  // Limpiar bits 0-3
    GPIOA->CRL |= (1 << 3);     // CNF0 = 10 (Input with pull-up/down)
    GPIOA->ODR &= ~(1 << 0);    // ODR0 = 0 (Selecciona Pull-down)

    while(1) {
        if(!(GPIOA->IDR & (1 << 0))) { // Si PA0 es nivel bajo (0)
            GPIOC->ODR |= (1 << 13);   // PC13 = 1 (Encender)
        } else {
            GPIOC->ODR &= ~(1 << 13);  // PC13 = 0 (Apagar)
        }
    }
}