- void RCC_Configuration(void)
- {
- /* RCC system reset(for debug purpose) */
- RCC_DeInit(); //将外设RCC寄存器重设为缺省值
- /* Enable HSE */
- RCC_HSEConfig(RCC_HSE_ON); //设置外部高速晶振（HSE ）
- /* Wait till HSE is ready */
- HSEStartUpStatus = RCC_WaitForHSEStartUp(); //等待HSE 起振
- 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); //设置AHB时钟（HCLK）
-
- /* PCLK2 = HCLK/2 */
- RCC_PCLK2Config(RCC_HCLK_Div2); //设置高速AHB时钟（PCLK2）
- /* PCLK1 = HCLK/2 */
- RCC_PCLK1Config(RCC_HCLK_Div2); //设置低速AHB时钟（PCLK1）
-
- /* PLLCLK = 8MHz * 9 = 72 MHz */
- RCC_PLLConfig(RCC_PLLSource_HSE_Div1, RCC_PLLMul_6); //设置PLL 时钟源及倍频系数
- /* Enable PLL */
- RCC_PLLCmd(ENABLE); //使能PLL
- /* 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 peripheral clocks --------------------------------------------------*/
- /* GPIOA,GPIOB,GPIOC,SPI1 and USART1 clock enable */
- RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB | RCC_APB2Periph_GPIOC |
- RCC_APB2Periph_USART1 |RCC_APB2Periph_SPI1, ENABLE);
- /* USART2,USART3,UART4 Periph clock enable */
- RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2 | RCC_APB1Periph_USART3 |
- RCC_APB1Periph_UART4, ENABLE); //USART2,USART3,UART4在APB1总线上
- }
- GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
- GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
- GPIO_Init(GPIOA, &GPIO_InitStructure);
-
- /* Configure USART1 Tx (PA9) as alternate function push-pull */
- GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;
- GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
- GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
- GPIO_Init(GPIOA, &GPIO_InitStructure);
- NVIC_InitTypeDef NVIC_InitStructure;
- /* Configure one bit for preemption priority */
- NVIC_PriorityGroupConfig(NVIC_PriorityGroup_0);
- /* Enable the SPI1 Interrupt */
- // NVIC_InitStructure.NVIC_IRQChannel = SPI1_IRQChannel ;
- // NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
- // NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
- // NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
- // NVIC_Init(&NVIC_InitStructure);
- NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQChannel; //选择串口1中断
- NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0; //抢占式中断优先级设置为0
- NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; //响应式中断优先级设置为0
- NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //使能中断
- NVIC_Init(&NVIC_InitStructure);
- USART_InitStructure.USART_BaudRate = 1200;
- USART_InitStructure.USART_WordLength = USART_WordLength_8b;
- USART_InitStructure.USART_StopBits = USART_StopBits_1;
- USART_InitStructure.USART_Parity = USART_Parity_No;
- USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
- USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
- USART_ClockInitStructure.USART_Clock = USART_Clock_Disable;
- USART_ClockInitStructure.USART_CPOL = USART_CPOL_Low;
- USART_ClockInitStructure.USART_CPHA = USART_CPHA_2Edge;
- USART_ClockInitStructure.USART_LastBit = USART_LastBit_Disable;
- USART_Init(USART1, &USART_InitStructure);
- USART_ClockInit(USART1, &USART_ClockInitStructure);
- USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);
- USART_Cmd(USART1, ENABLE);
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