STM32F3DiscoveryPWM设置后无法输出

iseafish

[mw_shl_code=c,true]void TIM3_GPIO_Config(void) { GPIO_InitTypeDef GPIO_InitStructure; RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3,ENABLE); RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA|RCC_AHBPeriph_GPIOB,ENABLE); GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6|GPIO_Pin_7; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF; GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; GPIO_Init(GPIOA,&GPIO_InitStructure); GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0|GPIO_Pin_1; GPIO_Init(GPIOB,&GPIO_InitStructure); } void TIM3_Mode_Config(void) { TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure; TIM_OCInitTypeDef TIM_OCInitStructure; // PWM??????±??? u16 CCR1_Val = 100; u16 CCR2_Val = 75; u16 CCR3_Val = 50; u16 CCR4_Val = 25; TIM_TimeBaseStructure.TIM_Period = 199; TIM_TimeBaseStructure.TIM_Prescaler = 7199; TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; TIM_TimeBaseInit(TIM3,&TIM_TimeBaseStructure); TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1; TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; TIM_OCInitStructure.TIM_Pulse = CCR1_Val; TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; TIM_OC1Init(TIM3, &TIM_OCInitStructure); TIM_OC1PreloadConfig(TIM3, TIM_OCPreload_Enable); /* PWM1 Mode configuration: Channel2 */ TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; TIM_OCInitStructure.TIM_Pulse = CCR2_Val; TIM_OC2Init(TIM3, &TIM_OCInitStructure); TIM_OC2PreloadConfig(TIM3, TIM_OCPreload_Enable); /* PWM1 Mode configuration: Channel3 */ TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; TIM_OCInitStructure.TIM_Pulse = CCR3_Val; TIM_OC3Init(TIM3, &TIM_OCInitStructure); TIM_OC3PreloadConfig(TIM3, TIM_OCPreload_Enable); /* PWM1 Mode configuration: Channel4 */ TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; TIM_OCInitStructure.TIM_Pulse = CCR4_Val; TIM_OC4Init(TIM3, &TIM_OCInitStructure); TIM_OC4PreloadConfig(TIM3, TIM_OCPreload_Enable); TIM_ARRPreloadConfig(TIM3, ENABLE); /* TIM3 enable counter */ TIM_Cmd(TIM3, ENABLE); } void TIM3_PWM_Init(void) { TIM3_GPIO_Config(); TIM3_Mode_Config(); } int main(void) { TIM3_PWM_Init(); while(1){} } [/mw_shl_code]

下载程序后，仿真也仿真不了，用示波器测试也测不出波形，我是第一次用STM32，可能只是遇到了一些很基础的问题，但我找不出来，希望有人能帮我看一下，拜托了。

iseafish

各位，我的问题解决了，原因是在配置的时候没有配置复用的AF接口，所以才会出错：
GPIO_PinAFConfig(GPIOA,GPIO_PinSource6,GPIO_AF_2);
GPIO_PinAFConfig(GPIOA,GPIO_PinSource7,GPIO_AF_2);
加上这两句代码之后，GPIOA的Pin6、Pin7才能输出正确的波形。

正点原子

帮顶.....