用stm32编程新年倒计时代码

你好，我可以回答这个问题。以下是一个用STM32编程的新年倒计时代码：

#include "stm32f10x.h"
#include "stm32f10x_gpio.h"
#include "stm32f10x_rcc.h"
#include "stm32f10x_tim.h"

int main(void)
{
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);

GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);

TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_TimeBaseStructure.TIM_Period = 7199;
TIM_TimeBaseStructure.TIM_Prescaler = 9999;
TIM_TimeBaseStructure.TIM_ClockDivision = 0;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);

TIM_Cmd(TIM2, ENABLE);

while (1)
{
if (TIM_GetFlagStatus(TIM2, TIM_FLAG_Update) == SET)
{
TIM_ClearFlag(TIM2, TIM_FLAG_Update);
GPIO_WriteBit(GPIOA, GPIO_Pin_0, (BitAction)(1 - GPIO_ReadOutputDataBit(GPIOA, GPIO_Pin_0)));
}
}
}

这个代码使用了STM32的定时器和GPIO模块，每秒钟会在GPIOA的第0个引脚上输出一个方波，可以用这个方波来控制LED等外部设备的闪烁，实现新年倒计时的效果。