【灵动微电子MM32F0121测评】3.PWM呼吸灯

#include "pwm_dsp.h"

void TIM1_PWM_Configure(void)

{

    RCC_ClocksTypeDef       RCC_Clocks;

    GPIO_InitTypeDef        GPIO_InitStruct;

    TIM_OCInitTypeDef       TIM_OCInitStruct;

    TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStruct;

    uint32_t                TIM_ClockFrequency = 0;

    uint32_t                HPRE = 0, PPRE2 = 0;



    // PWM参数配置

    uint32_t PWM_Frequency = 1000;    // 1kHz PWM频率

    uint16_t PWM_Period = 1000;       // 周期值(ARR)，占空比范围0-1000

    uint16_t PrescalerValue = 0;      // 预分频值



    // 1. 获取时钟频率

    HPRE  = READ_BIT(RCC->CFGR, RCC_CFGR_HPRE)  >> RCC_CFGR_HPRE_Pos;

    PPRE2 = READ_BIT(RCC->CFGR, RCC_CFGR_PPRE2) >> RCC_CFGR_PPRE2_Pos;

    RCC_GetClocksFreq(&RCC_Clocks);



    // 计算TIM1时钟频率

    if (HPRE < 8) {

        TIM_ClockFrequency = (PPRE2 < 4) ? RCC_Clocks.PCLK2_Frequency : RCC_Clocks.PCLK2_Frequency * 2;

    } else {

        TIM_ClockFrequency = (PPRE2 < 4) ? RCC_Clocks.PCLK2_Frequency * 2 : RCC_Clocks.PCLK2_Frequency * 4;

    }



    // 2. 计算预分频值 (目标计数器时钟 = 1MHz)

    PrescalerValue = (uint16_t)(TIM_ClockFrequency / 1000000) - 1;



    // 3. 初始化TIM1定时器

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);



    TIM_TimeBaseStructInit(&TIM_TimeBaseInitStruct);

    TIM_TimeBaseInitStruct.TIM_Prescaler = PrescalerValue;  // 设置预分频

    TIM_TimeBaseInitStruct.TIM_CounterMode = TIM_CounterMode_Up;

    TIM_TimeBaseInitStruct.TIM_Period = PWM_Period - 1;     // ARR值 (1000-1)

    TIM_TimeBaseInitStruct.TIM_ClockDivision = TIM_CKD_Div1;

    TIM_TimeBaseInitStruct.TIM_RepetitionCounter = 0;

    TIM_TimeBaseInit(TIM1, &TIM_TimeBaseInitStruct);



    // 4. 配置PWM模式 (初始占空比0%)

    TIM_OCStructInit(&TIM_OCInitStruct);

    TIM_OCInitStruct.TIM_OCMode = TIM_OCMode_PWM1;

    TIM_OCInitStruct.TIM_OutputState = TIM_OutputState_Enable;

    TIM_OCInitStruct.TIM_Pulse = 0;               // 初始CCR值(占空比)

    TIM_OCInitStruct.TIM_OCPolarity = TIM_OCPolarity_High;

    TIM_OCInitStruct.TIM_OCIdleState = TIM_OCIdleState_Set;



    TIM_OC1Init(TIM1, &TIM_OCInitStruct);  // 配置通道1

    TIM_OC2Init(TIM1, &TIM_OCInitStruct);  // 配置通道2



    // 启用预装载寄存器

    TIM_OC1PreloadConfig(TIM1, TIM_OCPreload_Enable);

    TIM_OC2PreloadConfig(TIM1, TIM_OCPreload_Enable);

    TIM_ARRPreloadConfig(TIM1, ENABLE);



    // 5. 配置GPIO为PWM输出

    RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOB, ENABLE);

    GPIO_PinAFConfig(GPIOB, GPIO_PinSource14, GPIO_AF_7);  // TIM1_CH1

    GPIO_PinAFConfig(GPIOB, GPIO_PinSource15, GPIO_AF_7);  // TIM1_CH2



    GPIO_StructInit(&GPIO_InitStruct);

    GPIO_InitStruct.GPIO_Pin = GPIO_Pin_14 | GPIO_Pin_15;

    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF_PP;

    GPIO_InitStruct.GPIO_Speed = GPIO_Speed_High;

    GPIO_Init(GPIOB, &GPIO_InitStruct);



    // 6. 使能TIM1和PWM输出

    TIM_Cmd(TIM1, ENABLE);

    TIM_CtrlPWMOutputs(TIM1, ENABLE);

}