学习STM32编程USART控制流水灯

　　关键代码usart.c：#ifdef __GNUC__   /* With GCC/RAISONANCE, small printf (option LD Linker->Libraries->Small printf      set to ＂Yes＂) calls __io_putchar() */   #define PUTCHAR_PROTOTYPE int __io_putchar(int ch) #else   #define PUTCHAR_PROTOTYPE int fputc(int ch, FILE *f) #endif // __GNUC__   PUTCHAR_PROTOTYPE {   /* Place your implementation of fputc here */   /* e.g. write a character to the USART */   USART_SendData(USART1, (uint8_t) ch);    /* Loop until the end of transmission */   while (USART_GetFlagStatus(USART1, USART_FLAG_TC) == RESET)   {}    return ch; }      #if USART1_RX_EN uint8_t USART1_RX_Buffer[USART_RX_MAX]={0}; uint8_t USART1_RX_Index=0; uint8_t USART1_RX_OverFlag=0; #endif  void USART1_Init(uint32_t baudRate) {     GPIO_InitTypeDef GPIO_InitStructure;     USART_InitTypeDef USART_InitStructure;     NVIC_InitTypeDef NVIC_InitStructure;          RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA,ENABLE);     RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1,ENABLE);          GPIO_PinAFConfig(GPIOA,GPIO_PinSource9,GPIO_AF_USART1);     GPIO_PinAFConfig(GPIOA,GPIO_PinSource10,GPIO_AF_USART1);          GPIO_InitStructure.GPIO_Pin=GPIO_Pin_9 | GPIO_Pin_10; 	GPIO_InitStructure.GPIO_Mode=GPIO_Mode_AF; 	GPIO_InitStructure.GPIO_OType=GPIO_OType_PP; 	GPIO_InitStructure.GPIO_Speed=GPIO_Fast_Speed; 	GPIO_InitStructure.GPIO_PuPd=GPIO_PuPd_UP; 	GPIO_Init(GPIOF,&GPIO_InitStructure);          USART_InitStructure.USART_BaudRate=baudRate;     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_Init(USART1,&USART_InitStructure);          USART_Cmd(USART1,ENABLE);      #if USART1_RX_EN     USART_ITConfig(USART1,USART_IT_RXNE,ENABLE);          NVIC_InitStructure.NVIC_IRQChannel=USART1_IRQn;     NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=1;     NVIC_InitStructure.NVIC_IRQChannelSubPriority=3;     NVIC_InitStructure.NVIC_IRQChannelCmd=ENABLE;     NVIC_Init(&NVIC_InitStructure); #endif      }  void USART1_IRQHandler(void) {     uint8_t Res;     if(USART_GetITStatus(USART1,USART_IT_RXNE)!=RESET)     {         //Res=USART1->DR;         Res=USART_ReceiveData(USART1);         if(USART1_RX_Index>=USART_RX_MAX)         {             USART1_RX_Index=0;         }         if(Res!=＂#＂)         {             USART1_RX_Buffer[USART1_RX_Index++]=Res;         }         else if(Res==＂#＂)         {             USART1_RX_Buffer[USART1_RX_Index++]=Res;             USART1_RX_OverFlag=1;         }     }     USART_ClearFlag(USART1,USART_FLAG_RXNE); }
　　main.c：LED_WorkModeTypeDef myLEDWorkMode=LED_MODE1;  const char stringMode1[8]=＂mode_1#＂; const char stringMode2[8]=＂mode_2#＂; const char *stringMode3=＂mode_3#＂;  int main(void) {     delay_init(168);     LED_Init();     USART1_Init(115200);     printf(＂System Started!r ＂);  	 	while(1) 	{		         if(USART1_RX_OverFlag==1)         {             if(strstr((const char *)USART1_RX_Buffer,stringMode1)!=NULL)             {                 printf(＂I＂m in mode_1!r ＂);                 myLEDWorkMode=LED_MODE1;             }             else if(strstr((const char *)USART1_RX_Buffer,stringMode2)!=NULL)             {                 printf(＂I＂m in mode_2!r ＂);                 myLEDWorkMode=LED_MODE2;             }             else if(strstr((const char *)USART1_RX_Buffer,stringMode3)!=NULL)             {                 printf(＂I＂m in mode_3!r ＂);                 myLEDWorkMode=LED_MODE3;             }                          USART1_RX_Index=0;             USART1_RX_OverFlag=0;             memset(USART1_RX_Buffer,0,USART_RX_MAX);         }         if(myLEDWorkMode==LED_MODE1)         {             LED_Mode1(1000);         }         else if(myLEDWorkMode==LED_MODE2)         {             LED_Mode2();         }         else if(myLEDWorkMode==LED_MODE3)         {             LED_Mode3();         } 	} }