高手帮我看看STM32F101的RS485通信

shenshujing 提问时间：2011-4-20 10:42 /

这个采用的是USART3，RE/ED接在一起，我把这个控制位置高了，就是很简单的发送一个数据给PC机，这边采用的RS485转RS232与电脑连接。但是不能正常发送数据，复位一次在串口接受界面看到00。请高手帮帮忙！
/*******************************************************************************
* File Name          : main.c
* Author             : Wuhan R&D Center, Embest
* Date First Issued : 08/08/2008
* Description        : Main program body
********************************************************************************/
/* Includes ------------------------------------------------------------------*/
#include "stm32f10x_lib.h"
#include
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
ErrorStatus HSEStartUpStatus;
/* Private function prototypes -----------------------------------------------*/
void RCC_Configuration(void);
void NVIC_Configuration(void);
void GPIO_Configuration(void);
void USART_Configuration(void);
/* Private functions ---------------------------------------------------------*/
/*******************************************************************************
* Function Name : main
* Description    : Main program.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
int main(void)
{ // u16 i=0;


#ifdef DEBUG
debug();
#endif
/* Configure the system clocks */
RCC_Configuration();

/* NVIC Configuration */
NVIC_Configuration();
/* Configure the GPIOs */
GPIO_Configuration();

/* Configure the USART1 */
USART_Configuration();

// printf("\r\n Welcome to WUHAN R&D Center,Embest \r\n");
// printf("\r\n Please Input Character From Keyboard \r\n");
//while(1 )
// {
//  if(USART_GetFlagStatus(USART1,USART_IT_RXNE)==SET)
//  {
//   i = USART_ReceiveData(USART1);
//   printf(" %c",i&0xFF);    /* print the input char */
//
//  }
// }
GPIOB->ODR = 0x0200;
for(;;)
{
    USART_SendData(USART3, 8); //发送一位数据
    while(USART_GetFlagStatus(USART3, USART_FLAG_TXE) == RESET);
    GPIOA->ODR = 0x0002;
}
}

#ifdef DEBUG
/*******************************************************************************
* Function Name : assert_failed
* Description    : Reports the name of the source file and the source line number
*                  where the assert error has occurred.
* Input          : - file: pointer to the source file name
*                  - line: assert error line source number
* Output         : None
* Return         : None
*******************************************************************************/
void assert_failed(u8* file, u32 line)
{
/* User can add his own implementation to report the file name and line number */
printf("\n\r Wrong parameter value detected on\r\n");
printf("       file %s\r\n", file);
printf("       line %d\r\n", line);

/* Infinite loop */
/* while (1)
{
} */
}
#endif
/*******************************************************************************
* Function Name : RCC_Configuration
* Description    : Configures the different system clocks.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
void RCC_Configuration(void)
{
/* 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)
{
    /* HCLK = SYSCLK */
    RCC_HCLKConfig(RCC_SYSCLK_Div1);

    /* PCLK2 = HCLK */
    RCC_PCLK2Config(RCC_HCLK_Div1);
    /* PCLK1 = HCLK/2 */
    RCC_PCLK1Config(RCC_HCLK_Div2);
    /* Flash 2 wait state */
    FLASH_SetLatency(FLASH_Latency_2);
    /* Enable Prefetch Buffer */
    FLASH_PrefetchBufferCmd(FLASH_PrefetchBuffer_Enable);
    /* 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 USART1 and GPIOA clock */
RCC_APB2PeriphClockCmd( RCC_APB2Periph_GPIOB|RCC_APB2Periph_GPIOA, ENABLE);
RCC_APB1PeriphClockCmd( RCC_APB1Periph_USART3,ENABLE);
}
/*******************************************************************************
* Function Name : NVIC_Configuration
* Description    : Configures Vector Table base location.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
void NVIC_Configuration(void)
{
#ifdef VECT_TAB_RAM
/* Set the Vector Table base location at 0x20000000 */
NVIC_SetVectorTable(NVIC_VectTab_RAM, 0x0);
#else /* VECT_TAB_FLASH */
/* Set the Vector Table base location at 0x08000000 */
NVIC_SetVectorTable(NVIC_VectTab_FLASH, 0x0);
#endif
}
/*******************************************************************************
* Function Name : GPIO_Configuration
* Description    : Configures the different GPIO ports.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
void GPIO_Configuration(void)
{
   GPIO_InitTypeDef GPIO_InitStructure;
/* Configure PC. as Output push-pull */
GPIO_InitStructure.GPIO_Pin =GPIO_Pin_0|GPIO_Pin_1|GPIO_Pin_4|GPIO_Pin_5|GPIO_Pin_6|GPIO_Pin_7|GPIO_Pin_11|GPIO_Pin_12;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;//输出
GPIO_Init(GPIOA, &GPIO_InitStructure);

   GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;
   GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
GPIO_Init(GPIOB, &GPIO_InitStructure);
/* Configure USART1 Tx (PB.10) as alternate function push-pull */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);

/* Configure USART1 Rx (PAB.11) as input floating */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);

}
/*******************************************************************************
* Function Name : USART_Configuration
* Description    : Configures the USART1.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
void USART_Configuration(void)
{
USART_InitTypeDef USART_InitStructure;
USART_ClockInitTypeDef USART_ClockInitStructure;
/* USART1 configuration -----------------------------------------------
-------*/
/* USART1 configured as follow:
        - BaudRate = 115200 baud
        - Word Length = 8 Bits
        - One Stop Bit
        - No parity
        - Hardware flow control disabled (RTS and CTS signals)
        - Receive and transmit enabled
        - USART Clock disabled
        - USART CPOL: Clock is active low
        - USART CPHA: Data is captured on the middle
        - USART LastBit: The clock pulse of the last data bit is not
output to
                         the SCLK pin
*/
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;
/* Configure the USART1 synchronous paramters */
USART_ClockInit(USART3, &USART_ClockInitStructure);
USART_InitStructure.USART_BaudRate = 9600;
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;
/* Configure USART1 basic and asynchronous paramters */
USART_Init(USART3, &USART_InitStructure);

/* Enable USART1 */
USART_Cmd(USART3, ENABLE);
}
/*******************************************************************************
* Function Name : fputc
* Description    : Retargets the C library printf function to the USART.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
int fputc(int ch, FILE *f)
{
/* Place your implementation of fputc here */
/* e.g. write a character to the USART */
USART_SendData(USART3, (u8) ch);
/* Loop until the end of transmission */
while(USART_GetFlagStatus(USART3, USART_FLAG_TC) == RESET)
{
}
return ch;
}
/******************* (C) COPYRIGHT 2007 STMicroelectronics *****END OF FILE****/
/*******************************************************************************
* File Name          : main.c
* Author             : Wuhan R&D Center, Embest
* Date First Issued : 08/08/2008
* Description        : Main program body
********************************************************************************/
/* Includes ------------------------------------------------------------------*/
#include "stm32f10x_lib.h"
#include
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
ErrorStatus HSEStartUpStatus;
/* Private function prototypes -----------------------------------------------*/
void RCC_Configuration(void);
void NVIC_Configuration(void);
void GPIO_Configuration(void);
void USART_Configuration(void);
/* Private functions ---------------------------------------------------------*/
/*******************************************************************************
* Function Name : main
* Description    : Main program.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
int main(void)
{ // u16 i=0;


#ifdef DEBUG
debug();
#endif
/* Configure the system clocks */
RCC_Configuration();

/* NVIC Configuration */
NVIC_Configuration();
/* Configure the GPIOs */
GPIO_Configuration();

/* Configure the USART1 */
USART_Configuration();

// printf("\r\n Welcome to WUHAN R&D Center,Embest \r\n");
// printf("\r\n Please Input Character From Keyboard \r\n");
//while(1 )
// {
//  if(USART_GetFlagStatus(USART1,USART_IT_RXNE)==SET)
//  {
//   i = USART_ReceiveData(USART1);
//   printf(" %c",i&0xFF);    /* print the input char */
//
//  }
// }
GPIOB->ODR = 0x0200;
for(;;)
{
    USART_SendData(USART3, 8); //发送一位数据
    while(USART_GetFlagStatus(USART3, USART_FLAG_TXE) == RESET);
    GPIOA->ODR = 0x0002;
}
}

#ifdef DEBUG
/*******************************************************************************
* Function Name : assert_failed
* Description    : Reports the name of the source file and the source line number
*                  where the assert error has occurred.
* Input          : - file: pointer to the source file name
*                  - line: assert error line source number
* Output         : None
* Return         : None
*******************************************************************************/
void assert_failed(u8* file, u32 line)
{
/* User can add his own implementation to report the file name and line number */
printf("\n\r Wrong parameter value detected on\r\n");
printf("       file %s\r\n", file);
printf("       line %d\r\n", line);

/* Infinite loop */
/* while (1)
{
} */
}
#endif
/*******************************************************************************
* Function Name : RCC_Configuration
* Description    : Configures the different system clocks.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
void RCC_Configuration(void)
{
/* 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)
{
    /* HCLK = SYSCLK */
    RCC_HCLKConfig(RCC_SYSCLK_Div1);

    /* PCLK2 = HCLK */
    RCC_PCLK2Config(RCC_HCLK_Div1);
    /* PCLK1 = HCLK/2 */
    RCC_PCLK1Config(RCC_HCLK_Div2);
    /* Flash 2 wait state */
    FLASH_SetLatency(FLASH_Latency_2);
    /* Enable Prefetch Buffer */
    FLASH_PrefetchBufferCmd(FLASH_PrefetchBuffer_Enable);
    /* 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 USART1 and GPIOA clock */
RCC_APB2PeriphClockCmd( RCC_APB2Periph_GPIOB|RCC_APB2Periph_GPIOA, ENABLE);
RCC_APB1PeriphClockCmd( RCC_APB1Periph_USART3,ENABLE);
}
/*******************************************************************************
* Function Name : NVIC_Configuration
* Description    : Configures Vector Table base location.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
void NVIC_Configuration(void)
{
#ifdef VECT_TAB_RAM
/* Set the Vector Table base location at 0x20000000 */
NVIC_SetVectorTable(NVIC_VectTab_RAM, 0x0);
#else /* VECT_TAB_FLASH */
/* Set the Vector Table base location at 0x08000000 */
NVIC_SetVectorTable(NVIC_VectTab_FLASH, 0x0);
#endif
}
/*******************************************************************************
* Function Name : GPIO_Configuration
* Description    : Configures the different GPIO ports.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
void GPIO_Configuration(void)
{
   GPIO_InitTypeDef GPIO_InitStructure;
/* Configure PC. as Output push-pull */
GPIO_InitStructure.GPIO_Pin =GPIO_Pin_0|GPIO_Pin_1|GPIO_Pin_4|GPIO_Pin_5|GPIO_Pin_6|GPIO_Pin_7|GPIO_Pin_11|GPIO_Pin_12;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;//输出
GPIO_Init(GPIOA, &GPIO_InitStructure);

   GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;
   GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
GPIO_Init(GPIOB, &GPIO_InitStructure);
/* Configure USART1 Tx (PB.10) as alternate function push-pull */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);

/* Configure USART1 Rx (PAB.11) as input floating */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);

}
/*******************************************************************************
* Function Name : USART_Configuration
* Description    : Configures the USART1.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
void USART_Configuration(void)
{
USART_InitTypeDef USART_InitStructure;
USART_ClockInitTypeDef USART_ClockInitStructure;
/* USART1 configuration -----------------------------------------------
-------*/
/* USART1 configured as follow:
        - BaudRate = 115200 baud
        - Word Length = 8 Bits
        - One Stop Bit
        - No parity
        - Hardware flow control disabled (RTS and CTS signals)
        - Receive and transmit enabled
        - USART Clock disabled
        - USART CPOL: Clock is active low
        - USART CPHA: Data is captured on the middle
        - USART LastBit: The clock pulse of the last data bit is not
output to
                         the SCLK pin
*/
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;
/* Configure the USART1 synchronous paramters */
USART_ClockInit(USART3, &USART_ClockInitStructure);
USART_InitStructure.USART_BaudRate = 9600;
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;
/* Configure USART1 basic and asynchronous paramters */
USART_Init(USART3, &USART_InitStructure);

/* Enable USART1 */
USART_Cmd(USART3, ENABLE);
}
/*******************************************************************************
* Function Name : fputc
* Description    : Retargets the C library printf function to the USART.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
int fputc(int ch, FILE *f)
{
/* Place your implementation of fputc here */
/* e.g. write a character to the USART */
USART_SendData(USART3, (u8) ch);
/* Loop until the end of transmission */
while(USART_GetFlagStatus(USART3, USART_FLAG_TC) == RESET)
{
}
return ch;
}
/******************* (C) COPYRIGHT 2007 STMicroelectronics *****END OF FILE****/

main.txt

下载

9.28 KB, 下载次数: 16, 下载积分: ST金币 -1

赞收藏评论4 发布时间：2011-4-20 10:42

4个回答

瘦猪呆兔回答时间：2011-4-20 11:25:01

RE:高手帮我看看STM32F101的RS485通信

貌似没有这个函数啊！ USART_SendData();

赞 0 评论

废鱼回答时间：2011-4-20 14:42:18

RE:高手帮我看看STM32F101的RS485通信

你配置了串口，但是没有配置串口的IO口。你把IO口再重新配置一下。还有就是要注意你使用的是串口3是不是需要映射。

赞 0 评论

zhouke58 回答时间：2011-4-20 15:50:24

RE:高手帮我看看STM32F101的RS485通信

你的配置看起来没有问题.给你说下接RS485的注意事项:
1.RE/ED端在转换发送接收时一定要加足够的延时,因为485IC比不了我们的STM32F101快.即使没有改变也最好加点延时
2.还有你的IO口: GPIOB->ODR = 0x0200;和GPIOA->ODR = 0x0002;是干什么用的?你是否有控制RE/ED端为发送.

赞 0 评论

shenshujing 回答时间：2011-4-20 16:59:40

RE:高手帮我看看STM32F101的RS485通信

谢谢高位的意见，软件应该没有问题，我选定芯片UASRT3貌似没有。
Available only on devices with a Flash memory density equal or higher than 64 Kbytes.
我选的是STM32F101C6。
我换了个UASRT2试了试可用发送了。