我之前看过你博客里面写到的关于运用STM32对外部脉冲计数的例程
我学习了下并实际操作了一下,根据自己实际情况稍微改了一点
程序如下:
/* Includes ------------------------------------------------------------------*/
#include "stm32f10x_lib.h"
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_ICInitTypeDef TIM_ICInitStructure;
ErrorStatus HSEStartUpStatus;
/* Private function prototypes -----------------------------------------------*/
void RCC_Configuration(void);
void GPIO_Configuration(void);
void NVIC_Configuration(void);
void Delay(vu32 nCount);
int count_out[3000];
int i,j;
/* Private functions ---------------------------------------------------------*/
/*******************************************************************************
* Function Name : Delay
* Description : Inserts a delay time.
* Input : nCount: specifies the delay time length.
* Output : None
* Return : None
*******************************************************************************/
/*******************************************************************************
* Function Name : main
* Description : Main program
* Input : None
* Output : None
* Return : None
*******************************************************************************/
int main(void)
{
#ifdef DEBUG
debug();
#endif
RCC_Configuration(); // System Clocks Configuration
NVIC_Configuration(); // NVIC configuration
GPIO_Configuration(); // Configure the GPIO ports
TIM_TimeBaseStructure.TIM_Period = 0x0400;
TIM_TimeBaseStructure.TIM_Prescaler = 0x00;
TIM_TimeBaseStructure.TIM_ClockDivision = 0x0;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure); // Time base configuration
TIM_ETRClockMode2Config(TIM2, TIM_ExtTRGPSC_OFF, TIM_ExtTRGPolarity_NonInverted, 0);
TIM_SetCounter(TIM2, 0);
TIM_Cmd(TIM2, ENABLE);
for(i=0;i<3000;i++)
{
count_out=TIM_GetCounter(TIM2);
Delay(100);
}
TIM_Cmd(TIM2, DISABLE);
}
/*******************************************************************************
* Function Name : RCC_Configuration
* Description : Configures the different system clocks.
* Input : None
* Output : None
* Return : None
*******************************************************************************/
void RCC_Configuration(void)
{
RCC_DeInit(); /* RCC system reset(for debug purpose) */
RCC_HSEConfig(RCC_HSE_ON); /* Enable HSE */
HSEStartUpStatus = RCC_WaitForHSEStartUp(); /* Wait till HSE is ready */
if(HSEStartUpStatus == SUCCESS) {
FLASH_PrefetchBufferCmd(FLASH_PrefetchBuffer_Enable); /* Enable Prefetch Buffer */
FLASH_SetLatency(FLASH_Latency_2); /* Flash 2 wait state */
RCC_HCLKConfig(RCC_SYSCLK_Div1); /* HCLK = SYSCLK */
RCC_PCLK2Config(RCC_HCLK_Div1); /* PCLK2 = HCLK */
RCC_PCLK1Config(RCC_HCLK_Div2); /* PCLK1 = HCLK/2 */
RCC_PLLConfig(RCC_PLLSource_HSE_Div1, RCC_PLLMul_9); /* PLLCLK = 8MHz * 9 = 72 MHz */
RCC_PLLCmd(ENABLE); /* Enable PLL */
while(RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET) {} /* Wait till PLL is ready */
RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK); /* Select PLL as system clock source */
while(RCC_GetSYSCLKSource() != 0x08) {} /* Wait till PLL is used as system clock source */
}
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE); /* TIM2 clock enable */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA , ENABLE); /* GPIOA、C clock enable */
}
/*******************************************************************************
* Function Name : GPIO_Configuration
* Description : Configure the GPIOD Pins.
* Input : None
* Output : None
* Return : None
*******************************************************************************/
void GPIO_Configuration(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
/* GPIOA Configuration */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; //50M时钟速度
GPIO_Init(GPIOA, &GPIO_InitStructure);
}
void Delay(vu32 nCount)
{
for(; nCount != 0; nCount--);
}
/*******************************************************************************
* Function Name : NVIC_Configuration
* Description : Configure the nested vectored interrupt controller.
* Input : None
* Output : None
* Return : None
*******************************************************************************/
void NVIC_Configuration(void)
{
#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
}
#ifdef DEBUG
/*******************************************************************************
* Function Name : assert_failed
* Description : Reports the name of the source file and the source line number
* where the assert_param error has occurred.
* Input : - file: pointer to the source file name
* - line: assert_param 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\r\n", file, line) */
while (1)
{
}
}
#endif
///////////////////////////////////////////////////
不知道哪里设置不对还是怎么的,n的值一直变化,就算没有外接脉冲信号也是
您能帮我看下吗