AVS úkol 1/2

/**
 ******************************************************************************
 * @file    main.c
 * @author  MCD Application Team
 * @version V1.1.0
 * @date    07-October-2011
 * @brief   Main program body
 ******************************************************************************
 * @attention
 *
 * THE PRESENT FIRMWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS
 * WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE
 * TIME. AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY
 * DIRECT, INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING
 * FROM THE CONTENT OF SUCH FIRMWARE AND/OR THE USE MADE BY CUSTOMERS OF THE
 * CODING INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.
 *
 * <h2><center>&copy; COPYRIGHT 2011 STMicroelectronics</center></h2>
 ******************************************************************************
 */

/* Includes ------------------------------------------------------------------*/
#include "stm32_eval.h"

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
#define SEQUENCE_LEN 13
#define SEQUENCE_STEP 100 /* in milliseconds */
const int sequence[SEQUENCE_LEN] = {0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 1, 1, 1};
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
uint32_t sequence_counter;
/* Private function prototypes -----------------------------------------------*/
/* Private functions ---------------------------------------------------------*/

void initClock() {
    RCC_SYSCLKConfig(RCC_SYSCLKSource_HSE); /* external crystal oscillator at 25 MHz */
    RCC_HCLKConfig(RCC_SYSCLK_Div1); /* AHB clock = SysClock */
    RCC_PCLK1Config(RCC_HCLK_Div1); /* APB1 clock = AHB clock = SysClock = 25 MHz */
}

void initGPIO() {
    GPIO_InitTypeDef initStruct;

    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOE, ENABLE); /* Enable clock for GPIO */
    GPIO_StructInit(&initStruct);
    initStruct.GPIO_Pin = GPIO_Pin_15 | GPIO_Pin_14;
    initStruct.GPIO_Mode = GPIO_Mode_OUT;
    initStruct.GPIO_OType = GPIO_OType_PP;
    initStruct.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOE, &initStruct);
}

void initTMR2() {
    TIM_TimeBaseInitTypeDef tim;
    TIM_TimeBaseStructInit(&tim);

    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);

    tim.TIM_Prescaler = 25000; /* 25 MHz / 25000 = 1 kHz = 1 ms */
    tim.TIM_CounterMode = TIM_CounterMode_Up;
    tim.TIM_Period = SEQUENCE_STEP;
    tim.TIM_ClockDivision = TIM_CKD_DIV1;
    tim.TIM_RepetitionCounter = 0;
    TIM_TimeBaseInit(TIM2, &tim);
    TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);
    TIM_Cmd(TIM2, ENABLE);
}

void initInterupts() {
    NVIC_InitTypeDef nvicStructure;
    nvicStructure.NVIC_IRQChannel = TIM2_IRQn;
    nvicStructure.NVIC_IRQChannelPreemptionPriority = 0;
    nvicStructure.NVIC_IRQChannelSubPriority = 1;
    nvicStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&nvicStructure);
}

void TIM2_IRQHandler()
{
    if (TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET)
    {
        TIM_ClearITPendingBit(TIM2, TIM_IT_Update);

        if (++sequence_counter == SEQUENCE_LEN)
            sequence_counter = 0;
        if (sequence[sequence_counter])
            GPIO_SetBits(GPIOE, GPIO_Pin_15);
        else
            GPIO_ResetBits(GPIOE, GPIO_Pin_15);

        GPIO_ToggleBits(GPIOE, GPIO_Pin_14);
    }
}

/**
 * Main program.
 * @return Nothing.
 */
int main(void) {
    initClock(); /* set clock source and frequency */
    initGPIO(); /* initialize the GPIO ports */
    initTMR2(); /* initialize the timer */
    initInterupts(); /* initialize the interrupt system and enable interrupts */

    sequence_counter = 0;

    while(1) {
        /* everything is handled in the interrupt handler */
    }
}
/******************* (C) COPYRIGHT 2011 STMicroelectronics *****END OF FILE****/