STM32的基本TIM在进行PWM捕获时候不能两个通道同时用？

只看该作者 · 2012-3-3 20:14

我的芯片是STM32F103ZET6 打算使用TIM4进行PWM信号的捕获，从手册得知是绑定Channel1和Channel2 Channel3和Channel4 CC1和CC3捕获高电平 CC2和CC4捕获低电平但是在实际编码中，在线调试发现始终是CC1/2在工作，CC3/4处于冻结状态，这样就无法采集Channel2所输入的信号。尝试过修改TIM的捕获设置的每个选项，发现没有效果，不知道问题所在。我的代码如下：

#include "stm32f10x.h"
#include "stm32f10x_usart.h"
#include "stm32f10x_tim.h"
TIM_OCInitTypeDef TIM_OCInitStructure;

void Rcc_Configuration(void);
void NVIC_Configuration(void);
void GPIO_Config(void);
void TIM_Configuration(void);
void Delay(uint32_t nCounts);
int IC2Value = 0;
int main ()
{

Rcc_Configuration();

NVIC_Configuration();

GPIO_Config();

TIM_Configuration();

while(1)

{}
}

void Rcc_Configuration(void)
{

SystemInit();

//启动GPIO

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA|RCC_APB2Periph_GPIOB|RCC_APB2Periph_GPIOC|RCC_APB2Periph_GPIOD|RCC_APB2Periph_GPIOE,ENABLE);

//启动AFIO

RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO,ENABLE);

//启动TIM4

RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4,ENABLE);
}

void NVIC_Configuration()
{

NVIC_InitTypeDef NVIC_InitStructure;

NVIC_InitStructure.NVIC_IRQChannel = TIM4_IRQn;                   //NVIC配置

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;

NVIC_Init(&NVIC_InitStructure);
}

void Delay(uint32_t nCounts)
{

u32 uCounts = nCounts;

for(;nCounts > 0;nCounts--)

for(;uCounts > 0;uCounts--);
}

void GPIO_Config(void)
{

GPIO_InitTypeDef GPIO_InitStructure;

//TIM4 PB7 CH2  PB9 CH4

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6|GPIO_Pin_8|GPIO_Pin_7|GPIO_Pin_9;                            //GPIO配置

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_Init(GPIOB, &GPIO_InitStructure);

//LED

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_Init(GPIOE, &GPIO_InitStructure);

}

void TIM_Configuration(void)
{

TIM_TimeBaseInitTypeDef TIM_BaseInitStructure;

TIM_ICInitTypeDef TIM_ICInitStructure;

//TIM4设置

//时基设置

TIM_BaseInitStructure.TIM_Prescaler = 36-1;

TIM_BaseInitStructure.TIM_ClockDivision = 0;

TIM_BaseInitStructure.TIM_CounterMode = TIM_CounterMode_Up;

TIM_BaseInitStructure.TIM_RepetitionCounter = 0;

TIM_TimeBaseInit(TIM4,&TIM_BaseInitStructure);

TIM_ICInitStructure.TIM_Channel = TIM_Channel_2|TIM_Channel_4;                //通道选择

TIM_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising;    //上升沿触发

TIM_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI ; //管脚与寄存器对应关系

TIM_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;          //输入预分频。

TIM_ICInitStructure.TIM_ICFilter = 0x0;                         //滤波设置，经历几个周期跳变认定波形稳定0x0～0xF

TIM_PWMIConfig(TIM4, &TIM_ICInitStructure);                //根据参数配置TIM外设信息


TIM_SelectInputTrigger(TIM4, TIM_TS_TI1FP1|TIM_TS_TI2FP2);             //选择IC1,2为触发源    这里不大懂触发源是怎么分配到捕获单元的

TIM_SelectSlaveMode(TIM4, TIM_SlaveMode_Reset);//TIM从模式：触发信号的上升沿重新初始化计数器和触发寄存器的更新事件

TIM_SelectMasterSlaveMode(TIM4, TIM_MasterSlaveMode_Enable); //启动定时器的被动触发

TIM_Cmd(TIM4, ENABLE);                               //启动TIM4

TIM_ITConfig(TIM4, TIM_IT_CC2|TIM_IT_CC4, ENABLE);    //打开中断

}

中断处理函数：
void TIM4_IRQHandler(void)
{
  extern u16 IC2Value;
  if(TIM_GetITStatus(TIM4,TIM_IT_CC1) == SET)
  {

TIM_ClearITPendingBit(TIM4, TIM_IT_CC1);             //清楚TIM的中断待处理位

IC2Value = TIM_GetCapture1(TIM4);
  }else if(TIM_GetITStatus(TIM4,TIM_IT_CC4) == SET)
  {

TIM_ClearITPendingBit(TIM4, TIM_IT_CC4);             //清楚TIM的中断待处理位

IC2Value = TIM_GetCapture4(TIM4);
  }
}