[N32G45x] N32 MCU PA15输出PWM波形

这里举个例子把PA15用作PWM输出引脚，用定时器TIM8产生PWM，程序配置如下：

int main(void)
{
    /* System Clocks Configuration */
    RCC_Configuration();

    /* GPIO Configuration */
    GPIO_Configuration();

    TIM_Intial(TIM8);

    while (1)
    {
    }
}

void RCC_Configuration(void)
{
    /* TIM8 clock enable */
    RCC_EnableAPB2PeriphClk(RCC_APB2_PERIPH_TIM8, ENABLE);
    RCC_EnableAPB2PeriphClk(RCC_APB2_PERIPH_AFIO,ENABLE);

    /* GPIOA,GPIOC,GPIOD  clock enable */
    RCC_EnableAPB2PeriphClk(RCC_APB2_PERIPH_GPIOA | RCC_APB2_PERIPH_GPIOC | RCC_APB2_PERIPH_GPIOD , ENABLE);
}

void GPIO_Configuration(void)
{
    GPIO_InitType GPIO_InitStructure;
    GPIO_ConfigPinRemap(GPIO_RMP_SW_JTAG_SW_ENABLE,ENABLE);        
    GPIO_ConfigPinRemap(GPIO_RMP1_TIM8,ENABLE);

    /* GPIOA Configuration:TIM8 Channel1, 2, 3 and 4 as alternate function push-pull */
    GPIO_InitStructure.Pin        = GPIO_PIN_15 ;
    GPIO_InitStructure.GPIO_Mode  = GPIO_Mode_AF_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

    GPIO_InitPeripheral(GPIOA, &GPIO_InitStructure);

    GPIO_InitStructure.Pin = GPIO_PIN_6 | GPIO_PIN_7 | GPIO_PIN_8 | GPIO_PIN_9 | GPIO_PIN_12  ;
    GPIO_InitPeripheral(GPIOC, &GPIO_InitStructure);

    GPIO_InitStructure.Pin = GPIO_PIN_2 ;
    GPIO_InitPeripheral(GPIOD, &GPIO_InitStructure);

}

void TIM_Intial(TIM_Module* TIMx)
{
    /* TIMx Configuration ---------------------------------------------------
    Generate 7 PWM signals with 4 different duty cycles:
    TIM1CLK = SystemCoreClock, Prescaler = 0, TIM1 counter clock = SystemCoreClock
    SystemCoreClock is set to 72 MHz for Low-density, Medium-density, High-density
    and Connectivity line devices and to 24 MHz for Low-Density Value line and
    Medium-Density Value line devices

    The objective is to generate 7 PWM signal at 17.57 KHz:
     - TIMx_Period = (SystemCoreClock / 17570) - 1
    The channel 1 and channel 1N duty cycle is set to 50%
    The channel 2 and channel 2N duty cycle is set to 37.5%
    The channel 3 and channel 3N duty cycle is set to 25%
    The channel 4 duty cycle is set to 12.5%
    The Timer pulse is calculated as follows:
     - ChannelxPulse = DutyCycle * (TIM1_Period - 1) / 100
    ----------------------------------------------------------------------- */
    /* Compute the value to be set in AR regiter to generate signal frequency at 17.57 Khz */
    TimerPeriod = 50; //(SystemCoreClock / 17570 ) - 1;
    /* Compute CCDAT1 value to generate a duty cycle at 50% for channel 1 and 1N */
    Channel1Pulse = (uint16_t)(((uint32_t)5 * (TimerPeriod - 1)) / 10);
    /* Compute CCDAT2 value to generate a duty cycle at 37.5%  for channel 2 and 2N */
    Channel2Pulse = (uint16_t)(((uint32_t)375 * (TimerPeriod - 1)) / 1000);
    /* Compute CCDAT3 value to generate a duty cycle at 25%  for channel 3 and 3N */
    Channel3Pulse = (uint16_t)(((uint32_t)25 * (TimerPeriod - 1)) / 100);
    /* Compute CCDAT4 value to generate a duty cycle at 12.5%  for channel 4 */
    Channel4Pulse = (uint16_t)(((uint32_t)125 * (TimerPeriod - 1)) / 1000);

    /* Time Base configuration */
    TIM_TimeBaseStructure.Prescaler = 0;
    TIM_TimeBaseStructure.CntMode   = TIM_CNT_MODE_UP;
    TIM_TimeBaseStructure.Period    = TimerPeriod;
    TIM_TimeBaseStructure.ClkDiv    = 0;
    TIM_TimeBaseStructure.RepetCnt  = 0;

    TIM_InitTimeBase(TIMx, &TIM_TimeBaseStructure);

    /* Channel 1, 2,3 and 4 Configuration in PWM mode */
    TIM_OCInitStructure.OcMode       = TIM_OCMODE_PWM2;
    TIM_OCInitStructure.OutputState  = TIM_OUTPUT_STATE_ENABLE;
    TIM_OCInitStructure.OutputNState = TIM_OUTPUT_NSTATE_ENABLE;
    TIM_OCInitStructure.Pulse        = Channel1Pulse;
    TIM_OCInitStructure.OcPolarity   = TIM_OC_POLARITY_HIGH;
    TIM_OCInitStructure.OcNPolarity  = TIM_OCN_POLARITY_HIGH;
    TIM_OCInitStructure.OcIdleState  = TIM_OC_IDLE_STATE_SET;
    TIM_OCInitStructure.OcNIdleState = TIM_OC_IDLE_STATE_RESET;
    TIM_InitOc1(TIMx, &TIM_OCInitStructure);

    TIM_OCInitStructure.Pulse = Channel3Pulse;
    TIM_InitOc3(TIMx, &TIM_OCInitStructure);
    TIM_OCInitStructure.Pulse = Channel4Pulse;
    TIM_InitOc4(TIMx, &TIM_OCInitStructure);

    // TIM_OCInitStructure.OutputNState = TIM_OUTPUT_NSTATE_DISABLE;
    TIM_OCInitStructure.Pulse = Channel2Pulse;
    TIM_InitOc2(TIMx, &TIM_OCInitStructure);

    /* TIM8 counter enable */
    TIM_Enable(TIMx, ENABLE);

    /* TIM8 Main Output Enable */
    TIM_EnableCtrlPwmOutputs(TIMx, ENABLE);
}