stm32f429-discovery +cubemx + USB转虚拟串口研究

系统管理员 2022-09-24 04:26 360阅读 0赞

在实验过stm32f302的USB转串口之后，仍对缺少上拉电阻或者说不能配置上拉的GPIO感到不安。

所以此次直接更新为stm32f429的开发板，贵就是有贵的好处，配置方法不拖泥带水。

按步来吧，先介绍版本：stm32cubemx version 4.15.1 STM32Cube v1.0 ; Firmware Package for family STM32F4 1.12.0; Keil 4.73

以下配置情况仅供参考，意外情况可以提问。

1.配置管脚，一开始用USART2，应该是引脚复用，结果该口没法用，改用USART1就OK. 还开了两个LED作为通讯指示。

![Center][]

![Center 1][]

2.配置时钟

![Center 2][]

3.串口1的配置

![Center 3][]

![Center 4][]

使用DMA作为发送模式妥妥的省资源。

![20160725153352097][]

4.USB底层配置

![20160725153429988][]

5.中断配置，需要打开DMA2中断

![20160725153417175][]

6.USB中间层配置

![20160725153443211][]

![20160725153456957][]

![20160725153508660][]

7.代码生成配置

![20160725153519728][]

![20160725153529926][]

8.关键代码示例

main函数中的关键定义及引用。 csdn 的代码好坑 本来都是标红的 都被

包围了。自己小心看吧

/* Includes ------------------------------------------------------------------*/
 #include "stm32f4xx_hal.h"
 #include "dma.h"
 #include "usart.h"
 #include "usb_device.h"
 #include "gpio.h"
 
 /* USER CODE BEGIN Includes */
 #include "usbd_cdc_if.h"
 /* USER CODE END Includes */
 
 /* Private variables ---------------------------------------------------------*/
 
 /* USER CODE BEGIN PV */
 /* Private variables ---------------------------------------------------------*/
 
 
 uint8_t aRxBuffer[1];
 uint8_t aTxBuffer[16];
 //extern uint8_t UserRxBufferFS[APP_RX_DATA_SIZE];
 /* USER CODE END PV */
 
 /* Private function prototypes -----------------------------------------------*/
 void SystemClock_Config(void);
 void Error_Handler(void);
 
 /* USER CODE BEGIN PFP */
 /* Private function prototypes -----------------------------------------------*/
 
 /* USER CODE END PFP */
 
 /* USER CODE BEGIN 0 */
 
 /* USER CODE END 0 */
 
 int main(void)
 {
 
 /* USER CODE BEGIN 1 */
 	
 /* USER CODE END 1 */
 
 /* MCU Configuration----------------------------------------------------------*/
 
 /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
 HAL_Init();
 
 /* Configure the system clock */
 SystemClock_Config();
 
 /* Initialize all configured peripherals */
 MX_GPIO_Init();
 MX_DMA_Init();
 MX_USB_DEVICE_Init();
 MX_USART2_UART_Init();
 MX_USART1_UART_Init();
 
 /* USER CODE BEGIN 2 */
 HAL_Delay(500);
 /* USER CODE END 2 */
 
 /* Infinite loop */
 /* USER CODE BEGIN WHILE */
 while (1)
 {
 /* USER CODE END WHILE */
 
 /* USER CODE BEGIN 3 */
 		if(HAL_UART_Receive_IT(&huart1,&aRxBuffer[0], 1)== HAL_OK) 
 		{
 			HAL_GPIO_TogglePin(LED_GREEN_GPIO_Port,LED_GREEN_Pin);//灯儿，不想用的屏蔽掉就OK
 			CDC_Transmit_FS(&aRxBuffer[0],1);
 		}
 	//	HAL_UART_Transmit(&huart1, test, sizeof(test), 100);
 	//	HAL_Delay(500);
 }
 /* USER CODE END 3 */
 
 }

9. usbd\_cdc\_if.c文件中的关键配置，标红部分为新加配置。

/* Includes ------------------------------------------------------------------*/
 #include "usbd_cdc_if.h"
 /* USER CODE BEGIN INCLUDE */
 /* USER CODE END INCLUDE */
 
 /** @addtogroup STM32_USB_OTG_DEVICE_LIBRARY
 * @{
 */
 
 /** @defgroup USBD_CDC 
 * @brief usbd core module
 * @{
 */ 
 
 /** @defgroup USBD_CDC_Private_TypesDefinitions
 * @{
 */ 
 /* USER CODE BEGIN PRIVATE_TYPES */
 extern UART_HandleTypeDef huart2; //这个没启用成功，还赖在这
 extern UART_HandleTypeDef huart1;
 /* The following structures groups all needed parameters to be configured for the 
 ComPort. These parameters can modified on the fly by the host through CDC class
 command class requests. */
 typedef struct
 {
 uint32_t bitrate;
 uint8_t format;
 uint8_t paritytype;
 uint8_t datatype;
 }LINE_CODING;
 
 //mch settings for usb vcp
 LINE_CODING linecoding =
 {
 9600, /* baud rate*/
 0x00, /* stop bits-1*/
 0x00, /* parity - none*/
 0x08 /* nb. of bits 8*/
 };
 extern uint8_t aRxBuffer[16];
 extern uint8_t aTxBuffer[16];	
 	
 /* USER CODE END PRIVATE_TYPES */ 
 /**
 * @}
 */ 
 
 /** @defgroup USBD_CDC_Private_Defines
 * @{
 */ 
 /* USER CODE BEGIN PRIVATE_DEFINES */
 /* Define size for the receive and transmit buffer over CDC */
 /* It's up to user to redefine and/or remove those define */
 #define APP_RX_DATA_SIZE 254
 #define APP_TX_DATA_SIZE 254
 /* USER CODE END PRIVATE_DEFINES */
 /**
 * @}
 */ 
 
 /** @defgroup USBD_CDC_Private_Macros
 * @{
 */ 
 /* USER CODE BEGIN PRIVATE_MACRO */
 /* USER CODE END PRIVATE_MACRO */
 
 /**
 * @}
 */ 
 
 /** @defgroup USBD_CDC_Private_Variables
 * @{
 */
 /* Create buffer for reception and transmission */
 /* It's up to user to redefine and/or remove those define */
 /* Received Data over USB are stored in this buffer */
 uint8_t UserRxBufferFS[APP_RX_DATA_SIZE];
 
 /* Send Data over USB CDC are stored in this buffer */
 uint8_t UserTxBufferFS[APP_TX_DATA_SIZE];
 
 /* USER CODE BEGIN PRIVATE_VARIABLES */
 /* USER CODE END PRIVATE_VARIABLES */
 
 /**
 * @}
 */ 
 
 /** @defgroup USBD_CDC_IF_Exported_Variables
 * @{
 */ 
 extern USBD_HandleTypeDef hUsbDeviceFS;
 /* USER CODE BEGIN EXPORTED_VARIABLES */
 /* USER CODE END EXPORTED_VARIABLES */
 
 /**
 * @}
 */ 
 
 /** @defgroup USBD_CDC_Private_FunctionPrototypes
 * @{
 */
 static int8_t CDC_Init_FS (void);
 static int8_t CDC_DeInit_FS (void);
 static int8_t CDC_Control_FS (uint8_t cmd, uint8_t* pbuf, uint16_t length);
 static int8_t CDC_Receive_FS (uint8_t* pbuf, uint32_t *Len);
 
 /* USER CODE BEGIN PRIVATE_FUNCTIONS_DECLARATION */
 /* USER CODE END PRIVATE_FUNCTIONS_DECLARATION */
 
 /**
 * @}
 */ 
 
 USBD_CDC_ItfTypeDef USBD_Interface_fops_FS = 
 {
 CDC_Init_FS,
 CDC_DeInit_FS,
 CDC_Control_FS, 
 CDC_Receive_FS
 };
 
 /* Private functions ---------------------------------------------------------*/
 /**
 * @brief CDC_Init_FS
 * Initializes the CDC media low layer over the FS USB IP
 * @param None
 * @retval Result of the operation: USBD_OK if all operations are OK else USBD_FAIL
 */
 static int8_t CDC_Init_FS(void)
 { 
 /* USER CODE BEGIN 3 */ 
 /* Set Application Buffers */
 USBD_CDC_SetTxBuffer(&hUsbDeviceFS, UserTxBufferFS, 0);
 USBD_CDC_SetRxBuffer(&hUsbDeviceFS, UserRxBufferFS);
 return (USBD_OK);
 /* USER CODE END 3 */ 
 }
 
 /**
 * @brief CDC_DeInit_FS
 * DeInitializes the CDC media low layer
 * @param None
 * @retval Result of the operation: USBD_OK if all operations are OK else USBD_FAIL
 */
 static int8_t CDC_DeInit_FS(void)
 {
 /* USER CODE BEGIN 4 */ 
 return (USBD_OK);
 /* USER CODE END 4 */ 
 }
 
 /**
 * @brief CDC_Control_FS
 * Manage the CDC class requests
 * @param cmd: Command code 
 * @param pbuf: Buffer containing command data (request parameters)
 * @param length: Number of data to be sent (in bytes)
 * @retval Result of the operation: USBD_OK if all operations are OK else USBD_FAIL
 */
 static int8_t CDC_Control_FS (uint8_t cmd, uint8_t* pbuf, uint16_t length)
 { 
 /* USER CODE BEGIN 5 */
 switch (cmd)
 {
 case CDC_SEND_ENCAPSULATED_COMMAND:
 
 break;
 
 case CDC_GET_ENCAPSULATED_RESPONSE:
 
 break;
 
 case CDC_SET_COMM_FEATURE:
 
 break;
 
 case CDC_GET_COMM_FEATURE:
 
 break;
 
 case CDC_CLEAR_COMM_FEATURE:
 
 break;
 
 /*******************************************************************************/
 /* Line Coding Structure */
 /*-----------------------------------------------------------------------------*/
 /* Offset | Field | Size | Value | Description */
 /* 0 | dwDTERate | 4 | Number |Data terminal rate, in bits per second*/
 /* 4 | bCharFormat | 1 | Number | Stop bits */
 /* 0 - 1 Stop bit */
 /* 1 - 1.5 Stop bits */
 /* 2 - 2 Stop bits */
 /* 5 | bParityType | 1 | Number | Parity */
 /* 0 - None */
 /* 1 - Odd */ 
 /* 2 - Even */
 /* 3 - Mark */
 /* 4 - Space */
 /* 6 | bDataBits | 1 | Number Data bits (5, 6, 7, 8 or 16). */
 /*******************************************************************************/
 case CDC_SET_LINE_CODING: 
 			linecoding.bitrate = (uint32_t)(pbuf[0] | (pbuf[1] << 8) | (pbuf[2] << 16) | (pbuf[3] << 24));
 			linecoding.format = pbuf[4];
 			linecoding.paritytype = pbuf[5];
 			linecoding.datatype = pbuf[6];
 	 huart1.Init.BaudRate = linecoding.bitrate;
 		 switch (linecoding.format)
 			{
 				case 0 : huart1.Init.StopBits = UART_STOPBITS_1; break;
 				case 1 : huart1.Init.StopBits = UART_STOPBITS_2; break;
 		//		case 2 : huart2.Init.StopBits = UART_STOPBITS_2; break;//有些位吧429库里没发现 ，奇怪
 			}
 		 switch (linecoding.paritytype)
 			{
 				case 0 : huart1.Init.Parity = UART_PARITY_NONE; break;
 				case 1 : huart1.Init.Parity = UART_PARITY_ODD; break;
 				case 2 : huart1.Init.Parity = UART_PARITY_EVEN; break;
 			}
 			//UART_WORDLENGTH_7B
 		 switch (linecoding.datatype)
 			{
 				case 9 : huart1.Init.WordLength = UART_WORDLENGTH_9B; break;
 				case 8 : huart1.Init.WordLength = UART_WORDLENGTH_8B; break;
 			}
 			HAL_UART_Init(&huart1) ;
 
 	/*		HAL_RS485Ex_Init(&huart2, UART_DE_POLARITY_HIGH, 0, 0); //这个地方就露馅了，本来是给485用的，后来就改成串口了，当然有兴趣的童鞋可以继续配置成485模式，记得引脚等。详细信息可以参考 http://www.stm32cube.com/article/120 */
 break;
 
 case CDC_GET_LINE_CODING: 
 				pbuf[0] = (uint8_t)(linecoding.bitrate);
 				pbuf[1] = (uint8_t)(linecoding.bitrate >> 8);
 				pbuf[2] = (uint8_t)(linecoding.bitrate >> 16);
 				pbuf[3] = (uint8_t)(linecoding.bitrate >> 24);
 				pbuf[4] = linecoding.format;
 				pbuf[5] = linecoding.paritytype;
 				pbuf[6] = linecoding.datatype;
 break;
 
 case CDC_SET_CONTROL_LINE_STATE:
 
 break;
 
 case CDC_SEND_BREAK:
 
 break; 
 
 default:
 break;
 }
 
 return (USBD_OK);
 /* USER CODE END 5 */
 }
 
 /**
 * @brief CDC_Receive_FS
 * Data received over USB OUT endpoint are sent over CDC interface 
 * through this function.
 * 
 * @note
 * This function will block any OUT packet reception on USB endpoint 
 * untill exiting this function. If you exit this function before transfer
 * is complete on CDC interface (ie. using DMA controller) it will result 
 * in receiving more data while previous ones are still not sent.
 * 
 * @param Buf: Buffer of data to be received
 * @param Len: Number of data received (in bytes)
 * @retval Result of the operation: USBD_OK if all operations are OK else USBD_FAIL
 */
 static int8_t CDC_Receive_FS (uint8_t* Buf, uint32_t *Len)
 {
 /* USER CODE BEGIN 6 */
 USBD_CDC_SetRxBuffer(&hUsbDeviceFS, &Buf[0]);
 USBD_CDC_ReceivePacket(&hUsbDeviceFS);
 	HAL_UART_Transmit_DMA(&huart1, Buf, *Len);
 	HAL_GPIO_TogglePin(LED_RED_GPIO_Port,LED_RED_Pin);//灯儿
 return (USBD_OK);
 /* USER CODE END 6 */ 
 }
 
 /**
 * @brief CDC_Transmit_FS
 * Data send over USB IN endpoint are sent over CDC interface 
 * through this function. 
 * @note
 * 
 * 
 * @param Buf: Buffer of data to be send
 * @param Len: Number of data to be send (in bytes)
 * @retval Result of the operation: USBD_OK if all operations are OK else USBD_FAIL or USBD_BUSY
 */
 uint8_t CDC_Transmit_FS(uint8_t* Buf, uint16_t Len)
 {
 uint8_t result = USBD_OK;
 /* USER CODE BEGIN 7 */ 
 USBD_CDC_HandleTypeDef *hcdc = (USBD_CDC_HandleTypeDef*)hUsbDeviceFS.pClassData;
 if (hcdc->TxState != 0){
 return USBD_BUSY;
 }
 USBD_CDC_SetTxBuffer(&hUsbDeviceFS, Buf, Len);
 result = USBD_CDC_TransmitPacket(&hUsbDeviceFS);
 /* USER CODE END 7 */ 
 return result;
 }

最后说一下，在115200波特率的时候会丢帧，可能跟一开始 的72MHz时钟有关。未验证  
上一张实物图吧，光说不练假把式

![20160725160135516][]

![20160725160541706][]

小玩至此结束，有疑问请留言。

[Center]: /images/20220719/e945bbf5327f4d7aace86fbc7cadee33.png
[Center 1]: /images/20220719/84bc19b80c2345a289b14a1c9557b213.png
[Center 2]: /images/20220719/a117f443ae0543a8994b131cfcb58172.png
[Center 3]: /images/20220719/928aa20d7f4b49a1b92864cccca56b0a.png
[Center 4]: /images/20220719/7bdc1c69513f4932a74501764d8b2cae.png
[20160725153352097]: /images/20220719/a2c3dc9a175e4f71a95ffc583a7f7e2a.png
[20160725153429988]: /images/20220719/203d0da5fc9540298208cdc9b58a2e0a.png
[20160725153417175]: /images/20220719/72f2db014eba428793af3061688bb83b.png
[20160725153443211]: /images/20220719/848afab63c4c49a3ae5c3623722a2875.png
[20160725153456957]: /images/20220719/2938f294452e4fbd85fb4341bb72c00d.png
[20160725153508660]: /images/20220719/f7f163d8a7c74ba5b97034a79ed3fc9e.png
[20160725153519728]: /images/20220719/15aab1b6e35b4917911f9c126c93c6e5.png
[20160725153529926]: /images/20220719/358df9ccfad2421599347ff63c8d3d6b.png
[20160725160135516]: /images/20220719/e395f1aa34a743b9aa152c5e096031ff.png
[20160725160541706]: /images/20220719/bddc606e7f0243a0a6d0b2ee25ddb09c.png