stm32F103片上串口USART1通信实验

硬件说明：如原理图所示，

103的PA10 PA11分别接CP2102usb转串口芯片的TXD RXD引脚。CP2102芯片是将串口和电脑USB接口进行了转接，方便应用灵活。

片上串口驱动代码如下。

 #include "usart.h"
 #include "stm32f10x_usart.h"

 #if SYSTEM_SUPPORT_UCOS
 #include "includes.h"    //ucos
 #endif

 #if 1
 #pragma import(__use_no_semihosting)             

 struct __FILE
 {
     int handle; 

 }; 

 FILE __stdout;
 _sys_exit(int x)
 {
     x = x;
 } 

 int fputc(int ch, FILE *f)
 {
         while(USART_GetFlagStatus(USART1,USART_FLAG_TC)==RESET);
     USART_SendData(USART1,(uint8_t)ch);
       return ch;
 }
 #endif 

 #if EN_USART1_RX
 //´®¿Ú1ÖжϷþÎñ³ÌÐò
 //×¢Òâ,¶ÁÈ¡USARTx->SRÄܱÜÃâĪÃûÆäÃîµÄ´íÎó
 u8 USART_RX_BUF[USART_REC_LEN];  //½ÓÊÕ»º³å,×î´óUSART_REC_LEN¸ö×Ö½Ú.

 u16 USART_RX_STA=;       //Receiving status marker

 void USART1_IRQHandler(void)
 {

     u8 res;
 #ifdef OS_CRITICAL_METHOD
     OSIntEnter();
 #endif
     if(USART_GetITStatus(USART1, USART_IT_RXNE) != RESET)  //½ÓÊÕÖжÏ(½ÓÊÕµ½µÄÊý¾Ý±ØÐëÊÇ0x0d 0x0a½áβ)
     {
         res =USART_ReceiveData(USART1);//(USART1->DR);    //¶ÁÈ¡½ÓÊÕµ½µÄÊý¾Ý

         if((USART_RX_STA&0x8000)==)//½ÓÊÕδÍê³É
             {
             if(USART_RX_STA&0x4000)//½ÓÊÕµ½ÁË0x0d
                 {
                 if(res!=0x0a)USART_RX_STA=;//½ÓÊÕ´íÎó,ÖØпªÊ¼
                 else USART_RX_STA|=0x8000;    //½ÓÊÕÍê³ÉÁË
                 }
             else //»¹Ã»ÊÕµ½0X0D
                 {
                 if(res==0x0d)USART_RX_STA|=0x4000;
                 else
                     {
                     USART_RX_BUF[USART_RX_STA&0X3FFF]= res;
                     USART_RX_STA++;
                     if(USART_RX_STA>(USART_REC_LEN-))USART_RX_STA=;//½ÓÊÕÊý¾Ý´íÎó,ÖØпªÊ¼½ÓÊÕ
                     }
                 }
             }   

      }
 #ifdef OS_CRITICAL_METHOD
     OSIntExit();
 #endif
 }
 #endif                                         

 //A11 RX  A10 TX

 void uart_init()
 {

   GPIO_InitTypeDef GPIO_InitStructure;
     USART_InitTypeDef USART_InitStructure;
     NVIC_InitTypeDef NVIC_InitStructure;

     RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1|RCC_APB2Periph_GPIOA, ENABLE);    //ʹÄÜUSART1£¬GPIOAʱÖÓ
   USART_DeInit(USART1);  //¸´Î»´®¿Ú1

     GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10; //PC.10
     GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
     GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;    //¸´ÓÃÍÆÍìÊä³ö
     GPIO_Init(GPIOA, &GPIO_InitStructure); //³õʼ»¯PA9

     GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;
     GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;//¸¡¿ÕÊäÈë
     GPIO_Init(GPIOA, &GPIO_InitStructure);  //³õʼ»¯PA10
     USART_InitStructure.USART_BaudRate = ;//Ò»°ãÉèÖÃΪ9600;
     USART_InitStructure.USART_WordLength = USART_WordLength_8b;//×Ö³¤Îª8λÊý¾Ý¸ñʽ
     USART_InitStructure.USART_StopBits = USART_StopBits_1;//Ò»¸öֹͣλ
     USART_InitStructure.USART_Parity = USART_Parity_No;//ÎÞÆæżУÑéλ
     USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;//ÎÞÓ²¼þÊý¾ÝÁ÷¿ØÖÆ
     USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;    //ÊÕ·¢Ä£Ê½

     USART_Init(USART1, &USART_InitStructure); //³õʼ»¯´®¿Ú
 #if EN_USART1_RX          //Èç¹ûʹÄÜÁ˽ÓÊÕ
    //Usart1 NVIC ÅäÖÃ
   NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
     NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority= ;//ÇÀÕ¼ÓÅÏȼ¶3
     NVIC_InitStructure.NVIC_IRQChannelSubPriority = ;        //×ÓÓÅÏȼ¶3
     NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;            //IRQͨµÀʹÄÜ
     NVIC_Init(&NVIC_InitStructure);    //¸ù¾ÝÖ¸¶¨µÄ²ÎÊý³õʼ»¯VIC¼Ä´æÆ÷

   USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);//¿ªÆôÖжÏ
 #endif
   USART_Cmd(USART1, ENABLE);                    //ʹÄÜ´®¿Ú 

 }

c文件

 #ifndef __USART_H
 #define __USART_H
 #include "sys.h"
 #include "stdio.h"     

 //////////////////////////////////////////////////////////////////////////////////
 #define USART_REC_LEN              200
 #define EN_USART1_RX               1        

 extern u8  USART_RX_BUF[USART_REC_LEN];
 extern u16 USART_RX_STA;                 

 void uart_init();

 #endif       

h文件

                         #include "sys.h"
                         #include "usart.h"
                         #include "delay.h"

 #define LED0 PAout(8)// DS0
 #define LED1 PBout(1)// DS1
 #define LED2 PBout(3)// DS1
 #define LED3 PAout(11)// DS1    

                         int main(void)
                         {

                         u8 t=;
                         u8 y=;
                         Stm32_Clock_Init();
                         delay_init();
                         uart_init(); 

                         while()
                         {
                         printf("t999:%d\n",t);
                         delay_ms();
                         t++;
                             if(y ==)y=;
                             switch(y)
                             {
                                 case :  LED0 = ;LED1 =; LED2 =; LED3=;break;
                                 case :     LED1 = ;LED0 =; LED2 =; LED3=; break;
                                 case :  LED2 = ;LED0 =; LED1 =; LED3=;break;
                                 case :     LED3 = ;LED1 =; LED0 =; LED2=;break;
                             }
                             y++;
                         }

                         return ;
                         }

main