STM32单片机学习(5) 定时器中断实验

*	* 软件功能:	 定时器中断实验* */#include "stm32f10x.h"#include "delay.h"void RCC_Configuration(void);void GPIO_Configuration(void);void NVIC_Configuration(void);void TIM3_Configuration(u16 arr,u16 psc);/*函数: int main(void)功能: main主函数参数: 无返回: 无/int main(void){RCC_Configuration();GPIO_Configuration();NVIC_Configuration();TIM3_Configuration(4999,7199);//10Khz的计数频率，计数到5000为500ms  //delay_init(72);GPIO_ResetBits(GPIOB,GPIO_Pin_0); while(1);   }/*函数: void RCC_Configuration(void)功能: 复位和时钟控制 配置参数: 无返回: 无/void RCC_Configuration(void){ErrorStatus HSEStartUpStatus;                    //定义外部高速晶体启动状态枚举变量RCC_DeInit();                                    //复位RCC外部设备寄存器到默认值RCC_HSEConfig(RCC_HSE_ON);                       //打开外部高速晶振HSEStartUpStatus = RCC_WaitForHSEStartUp();      //等待外部高速时钟准备好if(HSEStartUpStatus == SUCCESS)                  //外部高速时钟已经准别好{FLASH_PrefetchBufferCmd(FLASH_PrefetchBuffer_Enable); //开启FLASH预读缓冲功能，加速FLASH的读取。所有程序中必须的用法.位置：RCC初始化子函数里面，时钟起振之后FLASH_SetLatency(FLASH_Latency_2);                    //flash操作的延时RCC_HCLKConfig(RCC_SYSCLK_Div1);               //配置AHB(HCLK)时钟等于==SYSCLKRCC_PCLK2Config(RCC_HCLK_Div1);                //配置APB2(PCLK2)钟==AHB时钟RCC_PCLK1Config(RCC_HCLK_Div2);                //配置APB1(PCLK1)钟==AHB1/2时钟RCC_PLLConfig(RCC_PLLSource_HSE_Div1, RCC_PLLMul_9);  //配置PLL时钟 == 外部高速晶体时钟 * 9 = 72MHzRCC_PLLCmd(ENABLE);                                   //使能PLL时钟while(RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET)    //等待PLL时钟就绪{}RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK);            //配置系统时钟 = PLL时钟while(RCC_GetSYSCLKSource() != 0x08)                  //检查PLL时钟是否作为系统时钟{}}RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB | RCC_APB2Periph_AFIO, ENABLE);  //允许 GPIOB、AFIO时钟RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE); //时钟使能}/*函数: void GPIO_Configuration(void）功能: GPIO配置参数: 无返回: 无/void GPIO_Configuration(void){GPIO_InitTypeDef GPIO_InitStructure;        //定义GPIO初始化结构体GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; GPIO_Init(GPIOB, &GPIO_InitStructure); 	   //PB用于输出控制LED灯}void NVIC_Configuration(void)	 //中断分组和优先级配置	 详见《STM32的函数说明(中文).pdf》P165{NVIC_InitTypeDef NVIC_InitStructure;NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn;  //TIM3中断NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;  //先占优先级0级NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3;  //从优先级3级NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ通道被使能NVIC_Init(&NVIC_InitStructure);  //初始化NVIC寄存器}void TIM3_Configuration(u16 arr,u16 psc)	  //TIM3定时器配置   {TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;TIM_TimeBaseStructure.TIM_Period = arr; //设置在下一个更新事件装入活动的自动重装载寄存器周期的值	TIM_TimeBaseStructure.TIM_Prescaler =psc; //设置用来作为TIMx时钟频率除数的预分频值TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_div1; //设置时钟分割:TDTS = Tck_timTIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  //TIM向上计数模式TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure); //根据指定的参数初始化TIMx的时间基数单位/*((1+7199[TIM_Prescaler] )/72M)*(1+4999[TIM_Period] )=500,000us=500ms */ TIM_ITConfig(TIM3,TIM_IT_Update,ENABLE ); //使能指定的TIM3中断,允许更新中断TIM_Cmd(TIM3, ENABLE);  //使能TIMx}//定时器3中断服务程序void TIM3_IRQHandler(void)   //TIM3中断{if