STM32F107 TIM2定时不准，定1S，结果测试出来是880mS
晶振8M
原工程是按照默认25M晶振来配置的，所以system_stm32f10x.c文件中RCC配置改了一下，如下：
/*
RCC->CFGR2 |= (uint32_t)(RCC_CFGR2_PREDIV2_DIV5 | RCC_CFGR2_PLL2MUL8 |
RCC_CFGR2_PREDIV1SRC_PLL2 | RCC_CFGR2_PREDIV1_DIV5);*/
RCC->CFGR2 |= (uint32_t)(RCC_CFGR2_PREDIV2_DIV1 | RCC_CFGR2_PLL2MUL8 |
RCC_CFGR2_PREDIV1SRC_PLL2 | RCC_CFGR2_PREDIV1_DIV8);
Timer配置，NVIC配置，中断函数如下：
Void TIM_Configuration(void)
{
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
/* TIM2 configuration */
TIM_TimeBaseStructure.TIM_Period = 7199;
TIM_TimeBaseStructure.TIM_Prescaler = 9999;
TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseStructure.TIM_RepetitionCounter = 0x0000;
TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);
//TIM_PrescalerConfig(TIM2, 35999, TIM_PSCReloadMode_Immediate);
TIM_ARRPreloadConfig(TIM2, DISABLE);//禁止ARR预装载缓冲器
/* Immediate load of TIM2 Precaler value */
//TIM_PrescalerConfig(TIM2, ((SystemCoreClock/1200) - 1), TIM_PSCReloadMode_Immediate);
/* Clear TIM2 update pending flag */
TIM_ClearFlag(TIM2, TIM_FLAG_Update);
/* Clear TIM3 update pending flag */
/* Enable TIM2 Update interrupt */
TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);
/* TIM2 enable counter */
TIM_Cmd(TIM2, ENABLE);
}
void NVIC_Configuration(void)
{
NVIC_InitTypeDef NVIC_InitStructure;
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
/* Enable the TIM2 gloabal Interrupt */
NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
}
void TIM2_IRQHandler(void)
{
/* Clear TIM2 update interrupt */
if (TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET)
{
TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
/* Toggle GPIO */
GPIO_WriteBit(GPIOC, GPIO_Pin_6, (BitAction)(1 - GPIO_ReadOutputDataBit(GPIOC, GPIO_Pin_6)));
}
}
请各位大侠给点意见啊!
|
楼主
标题置顶
标题高亮
