STM32F4串口4标准库程序的问题

1万 · 2021-12-6 22:22

有一个板子，STM32F407VET6，串口4接在PC10和PC11上。
我用标准库写了个程序，通讯不上。

1万 · 2021-12-6 22:24

1万 · 2021-12-6 22:27

楼主程序可以公开吗？贴程序看下吧，这么说看不出什么原因

1万 · 2021-12-6 22:29

初始化代码如下：

//³õÊ¼»¯IO ´®¿Ú4
//bound:²¨ÌØÂÊ
void uart_init(u32 bound){
//GPIO¶Ë¿ÚÉèÖÃ
  GPIO_InitTypeDef GPIO_InitStructure;
      USART_InitTypeDef USART_InitStructure;
      NVIC_InitTypeDef NVIC_InitStructure;

      RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC,ENABLE); //Ê¹ÄÜGPIOCÊ±ÖÓ
      RCC_APB2PeriphClockCmd(RCC_APB1Periph_UART4,ENABLE);//Ê¹ÄÜUART4Ê±ÖÓ

      //´®¿Ú1¶ÔÓ¦Òý½Å¸´ÓÃÓ³Éä
      GPIO_PinAFConfig(GPIOC,GPIO_PinSource10,GPIO_AF_UART4); //GPIOC10¸´ÓÃÎªUART4
      GPIO_PinAFConfig(GPIOC,GPIO_PinSource11,GPIO_AF_UART4); //GPIOC11¸´ÓÃÎªUART4

      //USART1¶Ë¿ÚÅäÖÃ
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11 | GPIO_Pin_10; //GPIOC11ÓëGPIOC10
      GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;//¸´ÓÃ¹¦ÄÜ
      GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;       //ËÙ¶È50MHz
      GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; //ÍÆÍì¸´ÓÃÊä³ö
      GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP; //ÉÏÀ
      GPIO_Init(GPIOC,&GPIO_InitStructure); //³õÊ¼»¯PC11£¬PC10

//USART1 ³õÊ¼»¯ÉèÖÃ
      USART_InitStructure.USART_BaudRate = bound;//²¨ÌØÂÊÉèÖÃ
      USART_InitStructure.USART_WordLength = USART_WordLength_8b;//×Ö³¤Îª8Î»Êý¾Ý¸ñÊ½
      USART_InitStructure.USART_StopBits = USART_StopBits_1;//Ò»¸öÍ£Ö¹Î»
      USART_InitStructure.USART_Parity = USART_Parity_No;//ÎÞÆæÅ¼Ð£ÑéÎ»
      USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;//ÎÞÓ²¼þÊý¾ÝÁ÷¿ØÖÆ
      USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;       //ÊÕ·¢Ä£Ê½
  USART_Init(UART4, &USART_InitStructure); //³õÊ¼»¯´®¿Ú1

  USART_Cmd(UART4, ENABLE);  //Ê¹ÄÜ´®¿Ú1

      USART_ClearFlag(UART4, USART_FLAG_TC);

//#if EN_USART1_RX
//       USART_ITConfig(UART4, USART_IT_RXNE, ENABLE);//¿ªÆôÏà¹ØÖÐ¶Ï

//       //Usart1 NVIC ÅäÖÃ
//  NVIC_InitStructure.NVIC_IRQChannel = UART4_IRQn;//´®¿Ú1ÖÐ¶ÏÍ¨µÀ
//       NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=3;//ÇÀÕ¼ÓÅÏÈ¼¶3
//       NVIC_InitStructure.NVIC_IRQChannelSubPriority =3;             //×ÓÓÅÏÈ¼¶3
//       NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;                      //IRQÍ¨µÀÊ¹ÄÜ
//       NVIC_Init(&NVIC_InitStructure);       //¸ù¾ÝÖ¸¶¨µÄ²ÎÊý³õÊ¼»¯VIC¼Ä´æÆ÷¡¢

//#endif

}
开始我用中断，不行，后来又改成查询，都不行。

中断程序：
void UART4_IRQHandler(void)                      //´®¿Ú1ÖÐ¶Ï·þÎñ³ÌÐò
{
      u8 Res;
#if SYSTEM_SUPPORT_OS                //Èç¹ûSYSTEM_SUPPORT_OSÎªÕæ£¬ÔòÐèÒªÖ§³ÖOS.
      OSIntEnter();
#endif
      if(USART_GetITStatus(UART4, USART_IT_RXNE) != RESET)  //½ÓÊÕÖÐ¶Ï(½ÓÊÕµ½µÄÊý¾Ý±ØÐëÊÇ0x0d 0x0a½áÎ²)
      {
            Res =USART_ReceiveData(UART4);//(UART4->DR);       //¶ÁÈ¡½ÓÊÕµ½µÄÊý¾Ý


            if((USART_RX_STA&0x8000)==0)//½ÓÊÕÎ´Íê³É
            {
                     if(USART_RX_STA&0x4000)//½ÓÊÕµ½ÁË0x0d
                     {
                              if(Res!=0x0a)USART_RX_STA=0;//½ÓÊÕ´íÎó,ÖØÐÂ¿ªÊ¼
                              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-1))USART_RX_STA=0;//½ÓÊÕÊý¾Ý´íÎó,ÖØÐÂ¿ªÊ¼½ÓÊÕ
                              }
                     }
            }
  }
#if SYSTEM_SUPPORT_OS       //Èç¹ûSYSTEM_SUPPORT_OSÎªÕæ£¬ÔòÐèÒªÖ§³ÖOS.
      OSIntExit();
#endif
}

查询代码：
while (USART_GetFlagStatus(UART4, USART_FLAG_RXNE) == RESET);
            data=USART_ReceiveData(UART4);

请大神看看，如何修改代码？谢谢！

1万 · 2021-12-6 22:31

F407的UART4默认IO口是PA0和PA1,需要重复用功能重映射函数。
GPIO_PinRemapConfig()

1万 · 2021-12-6 22:33

另外UART与USART有所不同，F407的UART4并非USART4。楼主应该仔细阅读ST官方使用说明书。

1万 · 2021-12-6 22:35

1万 · 2021-12-6 22:40

怎么用啊？我不会用这个函数。还请明示。

1万 · 2021-12-6 22:42

我在百度上搜到的一些用法，还是不知道怎么写。

1万 · 2021-12-6 22:44

GPIO_PinRemapConfig(GPIO_Remap_SWJ_Disable, ENABLE);

1万 · 2021-12-6 22:46

我在stm32f4xx_gpio.h里没找到这个函数。不知道在哪里。

1万 · 2021-12-6 22:48

另外我用的标准库，有些地方改成了UART4。是不是USART的地方都要改成UART呀？谢谢

1万 · 2021-12-6 22:50

是的 USART 和 UART 是不一样的！一个是同步一个是非同步的意思吧！

1万 · 2021-12-6 22:52

谢谢！
typedef struct
{
  uint32_t USART_BaudRate;          /*!< This member configures the USART communication baud rate.
                                       The baud rate is computed using the following formula:
                                          - IntegerDivider = ((PCLKx) / (8 * (OVR8+1) * (USART_InitStruct->USART_BaudRate)))
                                          - FractionalDivider = ((IntegerDivider - ((u32) IntegerDivider)) * 8 * (OVR8+1)) + 0.5
                                       Where OVR8 is the "oversampling by 8 mode" configuration bit in the CR1 register. */

  uint16_t USART_WordLength;       /*!< Specifies the number of data bits transmitted or received in a frame.
                                       This parameter can be a value of @ref USART_Word_Length */

  uint16_t USART_StopBits;          /*!< Specifies the number of stop bits transmitted.
                                       This parameter can be a value of @ref USART_Stop_Bits */

  uint16_t USART_Parity;             /*!< Specifies the parity mode.
                                       This parameter can be a value of @ref USART_Parity
                                       @NOTE When parity is enabled, the computed parity is inserted
                                             at the MSB position of the transmitted data (9th bit when
                                             the word length is set to 9 data bits; 8th bit when the
                                             word length is set to 8 data bits). */

  uint16_t USART_Mode;             /*!< Specifies wether the Receive or Transmit mode is enabled or disabled.
                                       This parameter can be a value of @ref USART_Mode */

  uint16_t USART_HardwareFlowControl; /*!< Specifies wether the hardware flow control mode is enabled
                                       or disabled.
                                       This parameter can be a value of @ref USART_Hardware_Flow_Control */
} USART_InitTypeDef;
我找到这个结构体，在那个文件里搜UART，找不到。可怎么办呀？

1万 · 2021-12-6 22:54

GPIO_PinAFConfig(GPIOC,GPIO_PinSource10,GPIO_AF_UART4); //GPIOC10¸´ÓÃÎªUART4
      GPIO_PinAFConfig(GPIOC,GPIO_PinSource11,GPIO_AF_UART4); //GPIOC11¸´ÓÃÎªUART4
我有这两句，应该可以了吧。
函数说明：
/**
  * @brief  Changes the mapping of the specified pin.
  * @param  GPIOx: where x can be (A..K) to select the GPIO peripheral for STM32F405xx/407xx and STM32F415xx/417xx devices
  *                   x can be (A..I) to select the GPIO peripheral for STM32F42xxx/43xxx devices.
  *                   x can be (A, B, C, D and H) to select the GPIO peripheral for STM32F401xx devices.
  * @param  GPIO_PinSource: specifies the pin for the Alternate function.
  *       This parameter can be GPIO_PinSourcex where x can be (0..15).
  * @param  GPIO_AFSelection: selects the pin to used as Alternate function.
  *       This parameter can be one of the following values:
  *          @ARG GPIO_AF_RTC_50Hz: Connect RTC_50Hz pin to AF0 (default after reset)
  *          @arg GPIO_AF_MCO: Connect MCO pin (MCO1 and MCO2) to AF0 (default after reset)
  *          @arg GPIO_AF_TAMPER: Connect TAMPER pins (TAMPER_1 and TAMPER_2) to AF0 (default after reset)
  *          @arg GPIO_AF_SWJ: Connect SWJ pins (SWD and JTAG)to AF0 (default after reset)
  *          @arg GPIO_AF_TRACE: Connect TRACE pins to AF0 (default after reset)
  *          @arg GPIO_AF_TIM1: Connect TIM1 pins to AF1
  *          @arg GPIO_AF_TIM2: Connect TIM2 pins to AF1
  *          @arg GPIO_AF_TIM3: Connect TIM3 pins to AF2
  *          @arg GPIO_AF_TIM4: Connect TIM4 pins to AF2
  *          @arg GPIO_AF_TIM5: Connect TIM5 pins to AF2
  *          @arg GPIO_AF_TIM8: Connect TIM8 pins to AF3
  *          @arg GPIO_AF_TIM9: Connect TIM9 pins to AF3
  *          @arg GPIO_AF_TIM10: Connect TIM10 pins to AF3
  *          @arg GPIO_AF_TIM11: Connect TIM11 pins to AF3
  *          @arg GPIO_AF_I2C1: Connect I2C1 pins to AF4
  *          @arg GPIO_AF_I2C2: Connect I2C2 pins to AF4
  *          @arg GPIO_AF_I2C3: Connect I2C3 pins to AF4
  *          @arg GPIO_AF_SPI1: Connect SPI1 pins to AF5
  *          @arg GPIO_AF_SPI2: Connect SPI2/I2S2 pins to AF5
  *          @arg GPIO_AF_SPI4: Connect SPI4 pins to AF5
  *          @arg GPIO_AF_SPI5: Connect SPI5 pins to AF5
  *          @arg GPIO_AF_SPI6: Connect SPI6 pins to AF5
  *          @arg GPIO_AF_SAI1: Connect SAI1 pins to AF6 for STM32F42xxx/43xxx devices.
  *          @arg GPIO_AF_SPI3: Connect SPI3/I2S3 pins to AF6
  *          @arg GPIO_AF_I2S3ext: Connect I2S3ext pins to AF7
  *          @arg GPIO_AF_USART1: Connect USART1 pins to AF7
  *          @arg GPIO_AF_USART2: Connect USART2 pins to AF7
  *          @arg GPIO_AF_USART3: Connect USART3 pins to AF7
  *          @arg GPIO_AF_UART4: Connect UART4 pins to AF8
  *          @arg GPIO_AF_UART5: Connect UART5 pins to AF8
  *          @arg GPIO_AF_USART6: Connect USART6 pins to AF8
  *          @arg GPIO_AF_UART7: Connect UART7 pins to AF8
  *          @arg GPIO_AF_UART8: Connect UART8 pins to AF8
  *          @arg GPIO_AF_CAN1: Connect CAN1 pins to AF9
  *          @arg GPIO_AF_CAN2: Connect CAN2 pins to AF9
  *          @arg GPIO_AF_TIM12: Connect TIM12 pins to AF9
  *          @arg GPIO_AF_TIM13: Connect TIM13 pins to AF9
  *          @arg GPIO_AF_TIM14: Connect TIM14 pins to AF9
  *          @arg GPIO_AF_OTG_FS: Connect OTG_FS pins to AF10
  *          @arg GPIO_AF_OTG_HS: Connect OTG_HS pins to AF10
  *          @arg GPIO_AF_ETH: Connect ETHERNET pins to AF11
  *          @arg GPIO_AF_FSMC: Connect FSMC pins to AF12
  *          @arg GPIO_AF_FMC: Connect FMC pins to AF12 for STM32F42xxx/43xxx devices.
  *          @arg GPIO_AF_OTG_HS_FS: Connect OTG HS (configured in FS) pins to AF12
  *          @arg GPIO_AF_SDIO: Connect SDIO pins to AF12
  *          @arg GPIO_AF_DCMI: Connect DCMI pins to AF13
  *          @arg GPIO_AF_LTDC: Connect LTDC pins to AF14 for STM32F429xx/439xx devices.
  *          @arg GPIO_AF_EVENTOUT: Connect EVENTOUT pins to AF15
  * @retval None
  */
void GPIO_PinAFConfig(GPIO_TypeDef* GPIOx, uint16_t GPIO_PinSource, uint8_t GPIO_AF)
{
  uint32_t temp = 0x00;
  uint32_t temp_2 = 0x00;

  /* Check the parameters */
  assert_param(IS_GPIO_ALL_PERIPH(GPIOx));
  assert_param(IS_GPIO_PIN_SOURCE(GPIO_PinSource));
  assert_param(IS_GPIO_AF(GPIO_AF));

  temp = ((uint32_t)(GPIO_AF) << ((uint32_t)((uint32_t)GPIO_PinSource & (uint32_t)0x07) * 4)) ;
  GPIOx->AFR[GPIO_PinSource >> 0x03] &= ~((uint32_t)0xF << ((uint32_t)((uint32_t)GPIO_PinSource & (uint32_t)0x07) * 4)) ;
  temp_2 = GPIOx->AFR[GPIO_PinSource >> 0x03] | temp;
  GPIOx->AFR[GPIO_PinSource >> 0x03] = temp_2;
}

1万 · 2021-12-6 22:57

1万 · 2021-12-6 22:59

谢谢！
GPIO_PinAFConfig(GPIOC,GPIO_PinSource10,GPIO_AF_UART4); //GPIOC10¸´ÓÃÎªUART4
GPIO_PinAFConfig(GPIOC,GPIO_PinSource11,GPIO_AF_UART4); //GPIOC11¸´ÓÃÎªUART4
我有这两句。

1万 · 2021-12-6 23:01

UART不是那么好玩的，楼主还是先玩USART吧，

1万 · 2021-12-6 23:06

不是啊。我不是玩，硬件设计了那个口上了，那个家伙乱改口，我本来弄到串口1，它非弄到串口4.

1万 · 2021-12-6 23:09

那2句应该是对的，但是UART通行要求通讯的对方也是UART，同步方式要设置的寄存器不少，我也没玩过，还是先玩USART吧