/**
 ******************************************************************************
 * @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

void delay_ms(uint16_t t) {
    volatile unsigned long l = 0;
    for(uint16_t i = 0; i < t; i++) {
        for(l = 0; l < 800; l++);
    }
}

//----------Ejercicio 3----------
int main(void) {
    RCC->APB2ENR |= (1 << 2); // Reloj Puerto A

    // PA1 y PA2 como Salidas Push-Pull 2MHz
    GPIOA->CRL &= ~(0xFF << 4); // Limpiar bits 4 a 11 (PA1 y PA2)
    GPIOA->CRL |= (1 << 5) | (1 << 9); // MODE1=10, MODE2=10 (2MHz)

    // PA0 como Entrada Pull-down
    GPIOA->CRL &= ~(0xF << 0);
    GPIOA->CRL |= (1 << 3);
    GPIOA->ODR &= ~(1 << 0);

    uint8_t sentido = 0; // 0: Giro A, 1: Giro B

    while(1) {
        if(GPIOA->IDR & (1 << 0)) { // Botón presionado (High)
            // 1. Detener motor (Frenado)
            GPIOA->ODR &= ~((1 << 1) | (1 << 2));
            delay_ms(2000); // Esperar 2 segundos

            // 2. Cambiar sentido
            sentido = !sentido;

            // Esperar a que suelte el botón (Debounce simple)
            while(GPIOA->IDR & (1 << 0));
        }

        if(sentido == 0) {
            GPIOA->ODR |= (1 << 1);  // PA1 = 1
            GPIOA->ODR &= ~(1 << 2); // PA2 = 0
        } else {
            GPIOA->ODR &= ~(1 << 1); // PA1 = 0
            GPIOA->ODR |= (1 << 2);  // PA2 = 1
        }
    }
}