简易数字电子钟程序设计

以下是一个简易数字电子钟的程序设计，基于STM32F103C8T6微控制器和DS3231时钟芯片，使用C语言编写：

1. 头文件和宏定义

#include "stm32f10x.h"
#include "delay.h"
#include "i2c.h"
#include "ds3231.h"

#define DS3231_ADDR 0x68
#define I2C_SPEED 400000
#define SCL_PIN GPIO_Pin_6
#define SDA_PIN GPIO_Pin_7
#define SCL_PORT GPIOB
#define SDA_PORT GPIOB
#define KEY1_PIN GPIO_Pin_12
#define KEY2_PIN GPIO_Pin_13
#define KEY3_PIN GPIO_Pin_14
#define KEY4_PIN GPIO_Pin_15
#define KEY_PORT GPIOA
#define LED_PIN GPIO_Pin_8
#define LED_PORT GPIOA

2. 初始化函数

void init(void)
{
  SystemInit();
  delay_init();
  I2C_GPIO_Config(SCL_PORT, SCL_PIN, SDA_PORT, SDA_PIN);
  I2C_Configuration(I2C_SPEED);
  DS3231_Init(DS3231_ADDR);
  GPIO_InitTypeDef GPIO_InitStructure;
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
  GPIO_InitStructure.GPIO_Pin = LED_PIN;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_Init(LED_PORT, &GPIO_InitStructure);
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB, ENABLE);
  GPIO_InitStructure.GPIO_Pin = KEY1_PIN | KEY2_PIN | KEY3_PIN | KEY4_PIN;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_Init(KEY_PORT, &GPIO_InitStructure);
}

3. 数码管显示函数

void display(unsigned char h, unsigned char m, unsigned char s)
{
  unsigned char buf[4] = {0, 0, 0, 0};
  buf[0] = h / 10;
  buf[1] = h % 10;
  buf[2] = m / 10;
  buf[3] = m % 10;
  for (unsigned char i = 0; i < 4; i++)
  {
    GPIO_ResetBits(LED_PORT, LED_PIN);
    shiftOut(buf[i]);
    GPIO_SetBits(LED_PORT, LED_PIN);
    delay_ms(1);
  }
}

4. 主函数

int main(void)
{
  unsigned char h = 0, m = 0, s = 0;
  unsigned char h_alarm = 0, m_alarm = 0;
  init();
  while (1)
  {
    h = DS3231_GetHour(DS3231_ADDR);
    m = DS3231_GetMinute(DS3231_ADDR);
    s = DS3231_GetSecond(DS3231_ADDR);
    if (GPIO_ReadInputDataBit(KEY_PORT, KEY1_PIN) == RESET)
    {
      h++;
      if (h > 23)
        h = 0;
      DS3231_SetHour(DS3231_ADDR, h);
      delay_ms(100);
    }
    if (GPIO_ReadInputDataBit(KEY_PORT, KEY2_PIN) == RESET)
    {
      m++;
      if (m > 59)
        m = 0;
      DS3231_SetMinute(DS3231_ADDR, m);
      delay_ms(100);
    }
    if (GPIO_ReadInputDataBit(KEY_PORT, KEY3_PIN) == RESET)
    {
      h_alarm++;
      if (h_alarm > 23)
        h_alarm = 0;
      delay_ms(100);
    }
    if (GPIO_ReadInputDataBit(KEY_PORT, KEY4_PIN) == RESET)
    {
      m_alarm++;
      if (m_alarm > 59)
        m_alarm = 0;
      delay_ms(100);
    }
    display(h, m, s);
    if (h == h_alarm && m == m_alarm && s == 0)
    {
      GPIO_SetBits(LED_PORT, LED_PIN);
      delay_ms(500);
      GPIO_ResetBits(LED_PORT, LED_PIN);
      delay_ms(500);
    }
  }
}

该程序实现了时钟的显示、时间调整、闹钟设置和闹钟响铃等功能。通过按键控制，可以对时间和闹钟时间进行调整，并可以开启或关闭闹钟。