PWM 输入测占空比和频率问题

liweicnsu · 发表于 2015-5-6 11:57:19

void TIM2_PWMInput_Init(u16 arr,u16 psc)
{
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
NVIC_InitTypeDef NVIC_InitStructure;
TIM_ICInitTypeDef TIM2_ICInitStructure;
GPIO_InitTypeDef GPIO_InitStructure;

RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE); //使能定时器2时钟
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE); //使能GPIO外设

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3; //GPIO??
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);

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 = 0; //设置时钟分割:TDTS = Tck_tim
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //TIM向上计数模式
TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure); //根据TIM_TimeBaseInitStruct中指定的参数初始化TIMx的时间基数单位

/*配置中断优先级*/
NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);

TIM2_ICInitStructure.TIM_Channel = TIM_Channel_4;
TIM2_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising;
TIM2_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI;
TIM2_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;
TIM2_ICInitStructure.TIM_ICFilter = 0x0F;

TIM_PWMIConfig(TIM2, &TIM2_ICInitStructure); //PWM输入配置
TIM_SelectInputTrigger(TIM2, TIM_TS_TI2FP2); //选择有效输入端
TIM_SelectSlaveMode(TIM2, TIM_SlaveMode_Reset); //配置为主从复位模式
TIM_SelectMasterSlaveMode(TIM2, TIM_MasterSlaveMode_Enable);
TIM_ITConfig(TIM2, TIM_IT_CC2|TIM_IT_Update, ENABLE); //中断配置
TIM_ClearITPendingBit(TIM2, TIM_IT_CC2|TIM_IT_Update); //清除中断标志位
TIM_Cmd(TIM2, ENABLE);
}
void TIM3_PWMInput_Init(u16 arr,u16 psc)
{
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
NVIC_InitTypeDef NVIC_InitStructure;
TIM_ICInitTypeDef TIM3_ICInitStructure;
GPIO_InitTypeDef GPIO_InitStructure;

RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE); //使能定时器3时钟
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE); //使能GPIO外设

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6; //GPIO??
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);

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 = 0; //设置时钟分割:TDTS = Tck_tim
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //TIM向上计数模式
TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure); //根据TIM_TimeBaseInitStruct中指定的参数初始化TIMx的时间基数单位

/*配置中断优先级*/
NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);

TIM3_ICInitStructure.TIM_Channel = TIM_Channel_1;
TIM3_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising;
TIM3_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI;
TIM3_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;
TIM3_ICInitStructure.TIM_ICFilter = 0x0F;

TIM_PWMIConfig(TIM3, &TIM3_ICInitStructure); //PWM输入配置
TIM_SelectInputTrigger(TIM3, TIM_TS_TI2FP2); //选择有效输入端
TIM_SelectSlaveMode(TIM3, TIM_SlaveMode_Reset); //配置为主从复位模式
TIM_SelectMasterSlaveMode(TIM3, TIM_MasterSlaveMode_Enable);
TIM_ITConfig(TIM3, TIM_IT_CC2|TIM_IT_Update, ENABLE); //中断配置
TIM_ClearITPendingBit(TIM3, TIM_IT_CC2|TIM_IT_Update); //清除中断标志位
TIM_Cmd(TIM3, ENABLE);
}
//Ay
u16 period1 = 0;
u16 duty1 = 0;
u8 CollectFlag1 = 1;
//Ax
u16 period2 = 0;
u16 duty2 = 0;
u8 CollectFlag2 = 1;
void TIM2_IRQHandler(void)
{

if(CollectFlag1)
{
if (TIM_GetITStatus(TIM2, TIM_IT_CC2) != RESET)//捕获1发生捕获事件
{
duty1 = TIM_GetCapture1(TIM2); //采集占空比
period1 = TIM_GetCapture2(TIM2); //采集周期
}
CollectFlag1 = 0;
}
TIM_ClearITPendingBit(TIM2, TIM_IT_CC2|TIM_IT_Update); //清除中断标志位
}
//
void TIM3_IRQHandler(void)
{

if(CollectFlag2)
{
if (TIM_GetITStatus(TIM3, TIM_IT_CC2) != RESET)//捕获1发生捕获事件
{
duty2 = TIM_GetCapture1(TIM3); //采集占空比
period2 = TIM_GetCapture2(TIM3); //采集周期
}
CollectFlag2 = 0;
}
TIM_ClearITPendingBit(TIM3, TIM_IT_CC2|TIM_IT_Update); //清除中断标志位
}
程序得到的数值完全不对头,已知PWM输入的频率在100HZ左右,求大师指点