同一定时器产生不同频率PWM脉冲的问题

manhuazhiwu · 发表于 2013-11-15 20:24:19

依照KEIL安装文件例程编写的程序，想用同一定时器产生四路不同频率脉冲，程序如下
部分程序如下：现在的问题是频率较低时很正常但是频率很高时示波器显示就不正常了……请大家帮忙看看哪里有问题，奇怪的是仿真很好下载到stm32上用示波器观察就不行了
void GPIO_Configuration(void)
{
GPIO_InitTypeDef GPIO_InitStructure;

// GPIO_PinRemapConfig(GPIO_PartialRemap_TIM3, ENABLE);

/*GPIOA Configuration: TIM3 channel 1 and 2 as alternate function push-pull */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_Init(GPIOA, &GPIO_InitStructure);
}
void TIM_Configuration(void)
{
/* Time base configuration */
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_TimeBaseStructure.TIM_Period = 65535;         //这里必须是65535
TIM_TimeBaseStructure.TIM_Prescaler = 2;            //3分频
TIM_TimeBaseStructure.TIM_ClockDivision = 0;      //
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //向上计数模式

TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure); //初始化TIM3

/* Output Compare Toggle Mode configuration: Channel1 */
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_Toggle;    //输出比较翻转模式
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;   //使能通道1
TIM_OCInitStructure.TIM_Pulse = CCR1_Val;                       //待装入输出比较寄存器中的脉冲值

TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_Low; //输出为正逻辑
TIM_OC1Init(TIM3, &TIM_OCInitStructure); //写入配置

TIM_OC1PreloadConfig(TIM3, TIM_OCPreload_Disable); //使能或者失能TIMx在CCR1上的预装载寄存器

/* Output Compare Toggle Mode configuration: Channel2 */
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_Pulse = CCR2_Val;

TIM_OC2Init(TIM3, &TIM_OCInitStructure);

TIM_OC2PreloadConfig(TIM3, TIM_OCPreload_Disable);

/* Output Compare Toggle Mode configuration: Channel3 */
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_Pulse = CCR3_Val;

TIM_OC3Init(TIM3, &TIM_OCInitStructure);

TIM_OC3PreloadConfig(TIM3, TIM_OCPreload_Disable);

/* Output Compare Toggle Mode configuration: Channel4 */
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_Pulse = CCR4_Val;

TIM_OC4Init(TIM3, &TIM_OCInitStructure);

TIM_OC4PreloadConfig(TIM3, TIM_OCPreload_Disable);

/* TIM enable counter */
TIM_Cmd(TIM3, ENABLE); //开启计数器

/* TIM IT enable */ //TIM1中断源设置，开启相应通道的捕捉比较中断
TIM_ITConfig(TIM3, TIM_IT_CC1 | TIM_IT_CC2 | TIM_IT_CC3 | TIM_IT_CC4, ENABLE);

}
void TIM3_IRQHandler(void)
{
/* TIM3_CH1 toggling with frequency = 183.1 Hz */
if (TIM_GetITStatus(TIM3, TIM_IT_CC1) != RESET) //检查指定的TIM中断发生与否
{
TIM_ClearITPendingBit(TIM3, TIM_IT_CC1 ); //清除TIMx的中断待处理位

capture = TIM_GetCapture1(TIM3); //获得输入捕获值，即计数器中的计数值

TIM_SetCompare1(TIM3, capture + CCR1_Val );

//件也是相同的脉冲数
}

/* TIM3_CH2 toggling with frequency = 366.2 Hz */
if (TIM_GetITStatus(TIM3, TIM_IT_CC2) != RESET)
{
    TIM_ClearITPendingBit(TIM3, TIM_IT_CC2);
    capture = TIM_GetCapture2(TIM3);
    TIM_SetCompare2(TIM3, capture + CCR2_Val);

}

/* TIM3_CH3 toggling with frequency = 732.4 Hz */
if (TIM_GetITStatus(TIM3, TIM_IT_CC3) != RESET)
{
    TIM_ClearITPendingBit(TIM3, TIM_IT_CC3);
    capture = TIM_GetCapture3(TIM3);
    TIM_SetCompare3(TIM3, capture + CCR3_Val);
}

/* TIM3_CH4 toggling with frequency = 1464.8 Hz */
if (TIM_GetITStatus(TIM3, TIM_IT_CC4) != RESET)
{
    TIM_ClearITPendingBit(TIM3, TIM_IT_CC4);
    capture = TIM_GetCapture4(TIM3);
    TIM_SetCompare4(TIM3, capture + CCR4_Val);
}
}