/*RCC*****************************************************************************************************/
void RCC_Configuration(void)
{
/* SYSCLK, HCLK, PCLK2 and PCLK1 configuration -----------------------------*/
/* RCC system reset(for debug purpose) */
RCC_DeInit();
/* Enable HSE */
RCC_HSEConfig(RCC_HSE_ON);
/* Wait till HSE is ready */
HSEStartUpStatus = RCC_WaitForHSEStartUp();
if (HSEStartUpStatus == SUCCESS)
{
/* Enable Prefetch Buffer */
FLASH_PrefetchBufferCmd(FLASH_PrefetchBuffer_Enable);
/* Flash 2 wait state */
FLASH_SetLatency(FLASH_Latency_2);
/* HCLK = SYSCLK */
RCC_HCLKConfig(RCC_SYSCLK_Div1); /* 72M */
/* PCLK2 = HCLK */
RCC_PCLK2Config(RCC_HCLK_Div1); /* 72M */
/* PCLK1 = HCLK/2 */
RCC_PCLK1Config(RCC_HCLK_Div2); /* 36M */
/* PLLCLK = 8MHz * 9 = 72 MHz */
RCC_PLLConfig(RCC_PLLSource_HSE_Div1, RCC_PLLMul_9);
/* Enable PLL */
RCC_PLLCmd(ENABLE);
/* Wait till PLL is ready */
while (RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET)
{
}
/* Select PLL as system clock source */
RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK);
/* Wait till PLL is used as system clock source */
while(RCC_GetSYSCLKSource() != 0x08)
{
}
}
/* Enable GPIOx and AFIO clocks */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA
|RCC_APB2Periph_GPIOB
|RCC_APB2Periph_GPIOC
|RCC_APB2Periph_GPIOD
|RCC_APB2Periph_GPIOE
|RCC_APB2Periph_GPIOF
|RCC_APB2Periph_AFIO, ENABLE);
/* DMA clock enable */
//RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA2 | RCC_AHBPeriph_DMA1, ENABLE);
/* Enable USART clocks */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2 |
RCC_APB1Periph_USART3 |
RCC_APB1Periph_UART4 |
RCC_APB1Periph_UART5 ,ENABLE);
/* TIM clock enable */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2 |
RCC_APB1Periph_TIM3 |
RCC_APB1Periph_TIM4 |
RCC_APB1Periph_TIM5, ENABLE);
/* CAN Periph clock enable */
RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN, ENABLE);
/* Initialize the I/Os*/
}
/*Sys Tick*****************************************************************************************************/
void SysTick_Configuration(void)
{
SysTick_CLKSourceConfig(SysTick_CLKSource_HCLK); /*時鐘源*/
NVIC_SystemHandlerPriorityConfig(SystemHandler_SysTick,3,0);/*中斷入口，優先級*/
SysTick_SetReload(72000); /*中斷間隔*/
SysTick_CounterCmd(SysTick_Counter_Enable); //
SysTick_ITConfig(ENABLE); /*中斷使能*/
}
//系統滴答中斷
void SysTick_Handler(void)
{
app();
}
Note：
1.端口複用功能要打開，端口複用時鐘，RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);，詳見手冊rm0008的7.3節