先看下面的主程序：
/* Includes ------------------------------------------------------------------*/
#include "stm32f10x_lib.h"
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
u16 CCR1_Val = 15;
u16 CCR2_Val = 0x5FFF;
u16 CCR3_Val = 0x3FFF;
u16 CCR4_Val = 0x1FFF;
/* Private function prototypes -----------------------------------------------*/
void RCC_Configuration(void);
void GPIO_Configuration(void);
void NVIC_Configuration(void);
/* Private functions ---------------------------------------------------------*/
/*******************************************************************************
* Function Name : main
* Description : Main program
* Input : None
* Output : None
* Return : None
*******************************************************************************/
int main(void)
{
#ifdef DEBUG
debug();
#endif
/* System Clocks Configuration ---------------------------------------------*/
RCC_Configuration();
/* GPIO Configuration ------------------------------------------------------*/
GPIO_Configuration();
/* NVIC Configuration ------------------------------------------------------*/
NVIC_Configuration();
/* TIM2 Configuration ------------------------------------------------------*/
/* TIM2CLK = 36 MHz, Prescaler = 0x0, TIM2 counter clock = 36 MHz */
/* CC1 update rate = TIM2 counter clock / (2* CCR1_Val) ~= 549 Hz (1.82 ms) */
/* CC2 update rate = TIM2 counter clock / (2* CCR2_Val) ~= 732 Hz (1.36 ms) */
/* CC3 update rate = TIM2 counter clock / (2* CCR3_Val) ~= 1098 Hz (0.91 ms) */
/* CC4 update rate = TIM2 counter clock / (2* CCR4_Val) ~= 2197 Hz (0.45 ms) */
TIM_DeInit(TIM2);
TIM_TimeBaseStructInit(&TIM_TimeBaseStructure);
TIM_OCStructInit(&TIM_OCInitStructure);
/* Time base configuration */
TIM_TimeBaseStructure.TIM_Period = 359; //分频360
TIM_TimeBaseStructure.TIM_Prescaler = 99; //ARR=100
TIM_TimeBaseStructure.TIM_ClockDivision = 0x0;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);
/* Output Compare Toggle Mode configuration: Channel1 */
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_Toggle;
TIM_OCInitStructure.TIM_Channel = TIM_Channel_1;
TIM_OCInitStructure.TIM_Pulse = 15;// RCC= 15
TIM_OCInit(TIM2, &TIM_OCInitStructure);
TIM_OC1PreloadConfig(TIM2, TIM_OCPreload_Disable);
TIM_ARRPreloadConfig(TIM2, ENABLE);
TIM_ITConfig(TIM2, TIM_IT_CC1, ENABLE);
TIM_Cmd(TIM2, ENABLE);
while(1)
{
}
}
/*******************************************************************************
* Function Name : RCC_Configuration
* Description : Configures the different system clocks.
* Input : None
* Output : None
* Return : None
*******************************************************************************/
void RCC_Configuration(void)
{
/* RCC system reset(for debug purpose) */
RCC_DeInit();
/* Enable HSE */
RCC_HSEConfig(RCC_HSE_ON);
/* Wait till HSE is ready */
while(RCC_GetFlagStatus(RCC_FLAG_HSERDY) == RESET)
{
}
/* HCLK = SYSCLK */
RCC_HCLKConfig(RCC_SYSCLK_Div1);
/* PCLK2 = HCLK */
RCC_PCLK2Config(RCC_HCLK_Div1);
/* PCLK1 = HCLK/2 */
RCC_PCLK1Config(RCC_HCLK_Div2);
/* Flash 2 wait state */
*(vu32 *)0x40022000 = 0x01;
/* PLLCLK = 8MHz * 9 = 72 MHz */
RCC_PLLConfig(RCC_PLLSource_HSE_Div1, RCC_PLLMul_9);
/* Enable PLL */
RCC_PLLCmd(ENABLE);
/* Wait till PLL is ready */
while(RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET)
{
}
/* Select PLL as system clock source */
RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK);
/* Wait till PLL is used as system clock source */
while(RCC_GetSYSCLKSource() != 0x08)
{
}
/* Enable GPIOA clock */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB|RCC_APB2Periph_GPIOB, ENABLE);
/* Enable TIM2 clock */
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
}
/*******************************************************************************
* Function Name : GPIO_Configuration
* Description : Configures the TIM2 Pins.
* Input : None
* Output : None
* Return : None
*******************************************************************************/
void GPIO_Configuration(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
/* GPIOA Configuration:TIM2 Channel1, 2, 3 and 4 in Output */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_2 | GPIO_Pin_3;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8 | GPIO_Pin_9 | GPIO_Pin_10 |
GPIO_Pin_11 | GPIO_Pin_12 | GPIO_Pin_13 |
GPIO_Pin_14 | GPIO_Pin_15 ;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);
GPIOB->ODR=GPIO_Pin_8 | GPIO_Pin_9 | GPIO_Pin_10;
SysTick_CounterCmd(SysTick_Counter_Enable);
}
/*******************************************************************************
* Function Name : NVIC_Configuration
* Description : Configures NVIC and Vector Table base location.
* Input : None
* Output : None
* Return : None
*******************************************************************************/
void NVIC_Configuration(void)
{
NVIC_InitTypeDef NVIC_InitStructure;
#ifdef VECT_TAB_RAM
/* Set the Vector Table base location at 0x20000000 */
NVIC_SetVectorTable(NVIC_VectTab_RAM, 0x0);
#else /* VECT_TAB_FLASH */
/* Set the Vector Table base location at 0x08000000 */
NVIC_SetVectorTable(NVIC_VectTab_FLASH, 0x0);
#endif
/* Configure one bit for preemption priority */
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_1);
/* Enable the USART1 Interrupt */
NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQChannel;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
}
#ifdef DEBUG
/*******************************************************************************
* Function Name : assert_failed
* Description : Reports the name of the source file and the source line number
* where the assert error has occurred.
* Input : - file: pointer to the source file name
* - line: assert error line source number
* Output : None
* Return : None
*******************************************************************************/
void assert_failed(u8* file, u32 line)
{
/* User can add his own implementation to report the file name and line number,
ex: printf("Wrong parameters value: file %s on line %d
", file, line) */
/* Infinite loop */
while (1)
{
}
}
再看中断程序：
void TIM2_IRQHandler(void)
{
if (TIM_GetITStatus(TIM2, TIM_IT_CC1) != RESET)
{
if(GPIOB->ODR & GPIO_Pin_8)
GPIOB->BRR=GPIO_Pin_8;
else
GPIOB->BSRR=GPIO_Pin_8;
capture = TIM_GetCapture1(TIM2);
TIM_SetCompare1(TIM2, 15 + 1);
TIM_ClearITPendingBit(TIM2, TIM_IT_CC1);
}
}
现在我的问题是，如果我按以上配置程序，定时器没隔多久进一次中断函数TIM2_IRQHandler（）？
按我的理解是我分频后的CK_PSC=360000Hz,ARR的值是360，就是说我的频率是1kHz,然后RCC的值是15，就是说当计数到16后会产生事件更新，也就是会进中断程序，然后GPIO_Pin_8会产生翻转。
按照我的理解，就是说我的程序会没隔160us会进中断，但是实际上我用示波器查看时却为500us进中断函数，然后GPIO_Pin_8翻转一次。
请问高手们，这个进定时器中断函数的时间是与哪些值相关联的呢？
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