我的这段程序有什么问题？STM32的

只看该作者 · 2014-5-12 10:30

static void TIM4_Mode_Config(void)
{
TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
TIM_OCInitTypeDef  TIM_OCInitStructure;

/* PWMÐÅºÅµçÆ½Ìø±äÖµ */
u16 CCR1_Val = 30000 ;
//u16 CCR2_Val = 375;
//u16 CCR3_Val = 250;
//u16 CCR4_Val = 125;

/* -----------------------------------------------------------------------
TIM3 Configuration: generate 4 PWM signals with 4 different duty cycles:
TIM3CLK = 36 MHz, Prescaler = 0x0, TIM3 counter clock = 36 MHz
TIM3 ARR Register = 999 => TIM3 Frequency = TIM3 counter clock/(ARR + 1)
TIM3 Frequency = 36 KHz.
TIM3 Channel1 duty cycle = (TIM
   3_CCR1/ TIM3_ARR)* 100 = 50%
TIM3 Channel2 duty cycle = (TIM3_CCR2/ TIM3_ARR)* 100 = 37.5%
TIM3 Channel3 duty cycle = (TIM3_CCR3/ TIM3_ARR)* 100 = 25%
TIM3 Channel4 duty cycle = (TIM3_CCR4/ TIM3_ARR)* 100 = 12.5%
  ----------------------------------------------------------------------- */

  /* Time base configuration */
  TIM_TimeBaseStructure.TIM_Period = 60000;    //µ±¶¨Ê±Æ÷´Ó0¼ÆÊýµ½999£¬¼´Îª1000´Î£¬ÎªÒ»¸ö¶¨Ê±ÖÜÆÚ
  TIM_TimeBaseStructure.TIM_Prescaler = 0;       //ÉèÖÃÔ¤·ÖÆµ£º²»Ô¤·ÖÆµ£¬¼´Îª36MHz
  TIM_TimeBaseStructure.TIM_ClockDivision = 0; //ÉèÖÃÊ±ÖÓ·ÖÆµÏµÊý£º²»·ÖÆµ
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  //ÏòÉÏ¼ÆÊýÄ£Ê½

  TIM_TimeBaseInit(TIM4, &TIM_TimeBaseStructure);

  /* PWM1 Mode configuration: Channel1 */
  TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;       //ÅäÖÃÎªPWMÄ£Ê½1
  TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
  TIM_OCInitStructure.TIM_Pulse = CCR1_Val ;    //ÉèÖÃÌø±äÖµ£¬µ±¼ÆÊýÆ÷¼ÆÊýµ½Õâ¸öÖµÊ±£¬µçÆ½·¢ÉúÌø±ä
  TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_Low;  //µ±¶¨Ê±Æ÷¼ÆÊýÖµÐ¡ÓÚCCR1_ValÊ±Îª¸ßµçÆ½

  TIM_OC3Init(TIM4, &TIM_OCInitStructure);    //Ê¹ÄÜÍ¨µÀ3

  TIM_OC3PreloadConfig(TIM4, TIM_OCPreload_Enable);
  TIM_ARRPreloadConfig(TIM4, ENABLE);    // Ê¹ÄÜTIMÖØÔØ¼Ä´æÆ÷ARR

  /* TIM3 enable counter */
  TIM_Cmd(TIM4, ENABLE);                //Ê¹ÄÜ¶¨Ê±Æ÷3
}