STM32输出 PWM频率 占空比 连续可调~~

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来一波不同凡响的PWM

话不多说 直接上代码 我的平台是 stm32F407VGT6 PA0 输出 使用定时器TIM2

//编程输出可调的硬件PWM，频率范围1Hz - 1MHz，占空比0 - 100 %

uint32_t TIM2_PWM_FQ = 50;             /* TIM2_CH1_PWM输出 频率设置值，1-1000000 */
uint32_t TIM2_PWM_FQ_Old  = 0;
uint16_t TIM2_PWM_Pulse = 50;          /* TIM2_CH1_PWM输出 占空比设置值，0-100 */
uint16_t TIM2_PWM_Pulse_Old = 0;

uint32_t SystemCoreClock = 168000000;

/*
* 函数功能: 定时器4配置为硬件PWM模式(不开启TIM2的定时及DMA传输中断)
* TIM2_PWM_FQ:     TIM2_CH1_PWM 频率    1Hz至1000000Hz
* TIM2_PWM_Pulse:  TIM2_CH1_PWM 占空比  0-100%
*/
void StdPeriph_TIM2_PWM_Config(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;
    TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
    TIM_OCInitTypeDef  TIM_OCInitStructure;

    uint32_t temp32;
    uint32_t uhTimerfrequency;
    uint16_t uhTimerPeriod;
    uint16_t uhTimerPulse;

    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);  
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
    // GPIOB Configuration
    GPIO_InitStruct.GPIO_Pin = GPIO_Pin_0;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF;
    GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_DOWN;
    GPIO_InitStruct.GPIO_Speed = GPIO_Speed_100MHz;
    GPIO_Init(GPIOA, &GPIO_InitStruct);

    GPIO_PinAFConfig(GPIOA, GPIO_PinSource0, GPIO_AF_TIM2);

    uhTimerfrequency = 200000; /* 初始化 200KHz */
    temp32 = ((SystemCoreClock / 2) / uhTimerfrequency);
    if (temp32 > 65535) temp32 = 65535;
    uhTimerPeriod = (uint16_t) temp32;
    uhTimerPulse  = uhTimerPeriod * 50 / 100; /* 占空比50% */

    // Time base configuration
    TIM_TimeBaseStructure.TIM_Period = uhTimerPeriod - 1; /* 0x0000 and 0xFFFF */
    TIM_TimeBaseStructure.TIM_Prescaler = 0; /* 0x0000 and 0xFFFF */
    TIM_TimeBaseStructure.TIM_ClockDivision = 0;
    TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);

    // PWM1 Mode configuration: Channel1
    TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM2;
    TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
    TIM_OCInitStructure.TIM_Pulse = uhTimerPulse;
    TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_Low;

    TIM_OC1Init(TIM2, &TIM_OCInitStructure);
    TIM_OC1PreloadConfig(TIM2, TIM_OCPreload_Enable);
    TIM_ARRPreloadConfig(TIM2, ENABLE);
    TIM_GenerateEvent(TIM2, TIM_EventSource_Update);

    TIM_Cmd(TIM2, ENABLE);
}

/*
* 函数功能: 刷新TIM2_CH1_PWM输出的频率和占空比
* 修改TIM2_PWM_FQ的值，调节PWM频率(1Hz至1MHz)
* 修改TIM2_PWM_Pulse的值，调节PWM的占空比(0-100)
*/

void StdPeriph_TIM2_PWM_Update(void)
{
    uint32_t temp32;
    uint32_t uhTimerfrequency;
    uint16_t uhTimerPeriod;
    uint16_t uhTimerPrescaler;
    uint16_t uhTimerPulse;

    if ((TIM2_PWM_FQ_Old != TIM2_PWM_FQ) || (TIM2_PWM_Pulse_Old != TIM2_PWM_Pulse)) {
        TIM2_PWM_FQ_Old = TIM2_PWM_FQ;
        TIM2_PWM_Pulse_Old = TIM2_PWM_Pulse;
        if (TIM2_PWM_FQ >= 4000) {
            uhTimerfrequency = TIM2_PWM_FQ;  /* 定时器计时频率和PWM频率相等 */
            uhTimerPrescaler = 1;    /* 实际频率TIM2_PWM_FQ较大时，TIM2设置分频为1(不分频)   */
        } else {
            uhTimerfrequency = 4000; /* 实际频率TIM2_PWM_FQ较小时，和4000Hz的频率比较，看相差几倍 */
            uhTimerPrescaler = 4000 / TIM2_PWM_FQ;  /* 实际频率和4000相差的倍数作为TIM2的分频设置值 */
            uhTimerfrequency = uhTimerPrescaler * TIM2_PWM_FQ; /* TIM2分频后，计时周期变长，需要将uhTimerfrequency倍频  */
        }

        /* TIM2的周期要通过倍频uhTimerfrequency来计算,uhTimerPeriod = 84MHz / uhTimerfrequency */
        temp32 = ((SystemCoreClock / 2) / uhTimerfrequency);
        if (temp32 > 65535) temp32 = 65535;
        uhTimerPeriod = (uint16_t) temp32;

        if (TIM2_PWM_Pulse > 100) TIM2_PWM_Pulse = 100;
        uhTimerPulse = uhTimerPeriod * TIM2_PWM_Pulse / 100;

        TIM2->ARR  = uhTimerPeriod - 1;
        TIM2->PSC  = uhTimerPrescaler - 1;
        TIM2->CCR1 = uhTimerPulse;
        TIM2->EGR  = TIM_PSCReloadMode_Update;
    }
}

继续使用这个不同凡响的PWM吧