急急急！为什么我的TIM8不能够输出PWM，我就照着3.5的库函数提供TIM1的例程改的。求大神帮忙看看

David753 · 发表于 2017-5-3 19:37:07

#include "stm32f10x.h"

TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
TIM_OCInitTypeDef  TIM_OCInitStructure;
uint16_t TimerPeriod = 0;
uint16_t Channel1Pulse = 0, Channel2Pulse = 0, Channel3Pulse = 0, Channel4Pulse = 0;

/* Private function prototypes -----------------------------------------------*/
void RCC_Configuration(void);
void GPIO_Configuration(void);

int main(void)
{

  /* System Clocks Configuration */
  RCC_Configuration();

  /* GPIO Configuration */
  GPIO_Configuration();

  /* Compute the value to be set in ARR regiter to generate signal frequency at 17.57 Khz */
  TimerPeriod = (SystemCoreClock / 17570 ) - 1;
  /* Compute CCR1 value to generate a duty cycle at 50% for channel 1 and 1N */
  Channel1Pulse = (uint16_t) (((uint32_t) 5 * (TimerPeriod - 1)) / 10);
  /* Compute CCR2 value to generate a duty cycle at 37.5%  for channel 2 and 2N */
  Channel2Pulse = (uint16_t) (((uint32_t) 375 * (TimerPeriod - 1)) / 1000);
  /* Compute CCR3 value to generate a duty cycle at 25%  for channel 3 and 3N */
  Channel3Pulse = (uint16_t) (((uint32_t) 25 * (TimerPeriod - 1)) / 100);
  /* Compute CCR4 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.TIM_Prescaler = 0;
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
  TIM_TimeBaseStructure.TIM_Period = TimerPeriod;
  TIM_TimeBaseStructure.TIM_ClockDivision = 0;
  TIM_TimeBaseStructure.TIM_RepetitionCounter = 0;

  TIM_TimeBaseInit(TIM8, &TIM_TimeBaseStructure);

  /* Channel 1, 2,3 and 4 Configuration in PWM mode */
  TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM2;
  TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
  TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Enable;
  TIM_OCInitStructure.TIM_Pulse = Channel1Pulse;
  TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_Low;
  TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCNPolarity_High;
  TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Set;
  TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCIdleState_Reset;

  TIM_OC1Init(TIM8, &TIM_OCInitStructure);

  TIM_OCInitStructure.TIM_Pulse = Channel2Pulse;
  TIM_OC2Init(TIM8, &TIM_OCInitStructure);

  TIM_OCInitStructure.TIM_Pulse = Channel3Pulse;
  TIM_OC3Init(TIM8, &TIM_OCInitStructure);

  TIM_OCInitStructure.TIM_Pulse = Channel4Pulse;
  TIM_OC4Init(TIM8, &TIM_OCInitStructure);

  /* TIM1 counter enable */
  TIM_Cmd(TIM8, ENABLE);
//TIM_Cmd(TIM3, DISABLE);
  /* TIM1 Main Output Enable */
  TIM_CtrlPWMOutputs(TIM8, ENABLE);

  while (1)
  {

}
}

void RCC_Configuration(void)
{
  /* TIM1, GPIOA, GPIOB, GPIOE and AFIO clocks enable */
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM8 | RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOC|
                     RCC_APB2Periph_GPIOB |RCC_APB2Periph_AFIO, ENABLE);
}

void GPIO_Configuration(void)
{
  GPIO_InitTypeDef GPIO_InitStructure;

//GPIO_PinRemapConfig(GPIO_FullRemap_TIM3, DISABLE); /*以为会跟tim3的重映射冲突，专门关掉也没用啊*/

  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7 | GPIO_Pin_8 | GPIO_Pin_9;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_Init(GPIOC, &GPIO_InitStructure);

  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 ;
  GPIO_Init(GPIOB, &GPIO_InitStructure);
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7  ;
  GPIO_Init(GPIOA, &GPIO_InitStructure);

}