TIM5的PWM输出问题请教！！

bluesky_kun · 发表于 2014-11-19 17:06:15

各位朋友，帮忙看下程序错在哪里~~~~ 谢谢

目的：想在PA1引脚上输出PWM，用的是和战舰一样的stm32芯片。想用TIM5的第二通道产生，程序参考了原子个TIM3 PWM程序。

但一直输出不了PWM波。。请大家指点

void timer5_init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
uint16_t CCR2_Val = 333;
uint16_t PrescalerValue = 0;

RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM5, ENABLE);

/* GPIOA clock enable */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_1;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_Init(GPIOA, &GPIO_InitStructure);

/* Compute the prescaler value */
PrescalerValue = (uint16_t) (SystemCoreClock / 24000000) - 1;
/* Time base configuration */
TIM_TimeBaseStructure.TIM_Period = 665;
TIM_TimeBaseStructure.TIM_Prescaler = PrescalerValue;
TIM_TimeBaseStructure.TIM_ClockDivision = 0;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;

TIM_TimeBaseInit(TIM5, &TIM_TimeBaseStructure);

/* PWM1 Mode configuration: Channel1 */
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_Pulse = CCR2_Val;
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;

TIM_OC2Init(TIM5, &TIM_OCInitStructure);

TIM_OC2PreloadConfig(TIM5, TIM_OCPreload_Enable);

TIM_ARRPreloadConfig(TIM5, ENABLE);

/* TIM5 enable counter */
TIM_Cmd(TIM5, ENABLE);

}