在STM32F103上使用TD301D485H模块通过USB转485/422串口线与电脑通信
- TXD (TD301D485H) -> PA2 (STM32F103)
- RXD (TD301D485H) -> PA3 (STM32F103)
- CON (TD301D485H) -> PA1 (STM32F103)
由于485是半双工通信，需要在发送和接收时控制方向引脚（CON）。
- CON = 0：发送模式
- CON = 1：接收模式
参考教程：
【【工作STM32】第10集 STM32串口DMA模式与收发不定长数据 | keysking的stm32教程】 【工作STM32】第10集 STM32串口DMA模式与收发不定长数据 | keysking的stm32教程_哔哩哔哩_bilibili
rs485和教程中的串口使用时候的区别就是多了CON控制方向引脚
使用cubemx配置
代码：
/* USER CODE BEGIN Header */
/**
******************************************************************************
* @file : main.c
* @brief : Main program body
******************************************************************************
* @attention
*
* Copyright (c) 2025 STMicroelectronics.
* All rights reserved.
*
* This software is licensed under terms that can be found in the LICENSE file
* in the root directory of this software component.
* If no LICENSE file comes with this software, it is provided AS-IS.
*
******************************************************************************
*/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "dma.h"
#include "tim.h"
#include "usart.h"
#include "gpio.h"
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "stm32f1xx_hal.h"
#include "OLED.h"
#include "led.h"
#include "OLED_Data.h"
#include "ch452a.h"
#include "key.h"
#include "oled_show.h"
#include "input_system.h"
#include "Rotary.h"
#include "at24c32.h"
#include "soft_i2c.h"
#include "delay.h"
#include "function.h"
#include "string.h"
/* USER CODE END Includes */
/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
/* USER CODE END PTD */
/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
/* USER CODE END PD */
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
/* USER CODE END PM */
/* Private variables ---------------------------------------------------------*/
/* USER CODE BEGIN PV */
unsigned char EEDATA;
uint8_t rxBuffer[50];
volatile uint8_t usart2_tx_complete = 0; // 发送完成标志
/* USER CODE END PV */
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
/* USER CODE BEGIN PFP */
/* USER CODE END PFP */
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
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//volatile uint8_t ch452_key_event = 0;
//���ڲ��Ի�����
extern uint8_t OLED_DisplayBuf[64][128];
// �жϻص�
void HAL_GPIO_EXTI_Callback(uint16_t GPIO_Pin) {
if(GPIO_Pin == CH452_DOUT_PIN) {
ch452_key_event = 1;
}
}
//extern DMA_HandleTypeDef hdma_usart2_rx；
extern DMA_HandleTypeDef hdma_usart2_rx;
void RS485_Send(uint8_t *data, uint16_t size) {
HAL_GPIO_WritePin(GPIOA, GPIO_PIN_1, GPIO_PIN_RESET); // 发送模式
usart2_tx_complete = 0;
HAL_UART_Transmit_DMA(&huart2, data, size); // 非阻塞发送
}
void HAL_UART_TxCpltCallback(UART_HandleTypeDef *huart) {
if (huart == &huart2) {
HAL_GPIO_WritePin(GPIOA, GPIO_PIN_1, GPIO_PIN_SET); // 发送完成后切接收模式
usart2_tx_complete = 1;
}
}
void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart) {
if (huart == &huart2) {
RS485_Send(rxBuffer, 3); // 回传数据
HAL_UART_Receive_DMA(&huart2, rxBuffer, 3); // 重启接收
}
}
void HAL_UARTEx_RxEventCallback(UART_HandleTypeDef *huart, uint16_t Size){
if (huart == &huart2) {
RS485_Send(rxBuffer, Size); // 回传数据
HAL_UARTEx_ReceiveToIdle_DMA(&huart2, rxBuffer, sizeof(rxBuffer));
__HAL_DMA_DISABLE_IT(&hdma_usart2_rx,DMA_IT_HT);
}
}
/* USER CODE END 0 */
/**
* @brief The application entry point.
* @retval int
*/
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();
/* USER CODE BEGIN Init */
/* USER CODE END Init */
/* Configure the system clock */
SystemClock_Config();
/* USER CODE BEGIN SysInit */
/* USER CODE END SysInit */
/* Initialize all configured peripherals */
MX_GPIO_Init();
MX_DMA_Init();
MX_TIM4_Init();
MX_USART2_UART_Init();
/* USER CODE BEGIN 2 */
led_init();
OLED_Init();
CH452_Init();
Input_Init();
Encoder_Init() ;
Storage_Init();
char message[]="Hello World";
uint8_t test_data[] = "Hello, PC!\r\n";
OLED_ShowGrayImage(epd_bitmap_simplecolor6464, 0, 0, 64, 64);
// OLED_ShowGrayImage(epd_bitmap_HWL6464, 65, 0, 64, 64);
OLED_ShowGrayImage(epd_bitmap_momo6464, 129, 0, 64, 64);
HAL_Delay(500);
//Buffer_DrawString(40, 0, "AAAAAA",0x0f, 16,0);
Buffer_DrawString(40, 0, "DGL",0x0f, 16,1);
//Buffer_DrawTest(20, 21, 'A', 0x0f);
Buffer_DrawTest(1,1, '1', 0x0f,0);
//Buffer_DrawPixel(0, 0, 0x0f);
Buffer_Swap(); // ��ʾ
HAL_GPIO_WritePin(GPIOA, GPIO_PIN_1, GPIO_PIN_SET); // 接收模式
// HAL_UART_Receive_DMA(&huart2, rxBuffer, 3);
HAL_UARTEx_ReceiveToIdle_DMA(&huart2, rxBuffer, sizeof(rxBuffer));
__HAL_DMA_DISABLE_IT(&hdma_usart2_rx,DMA_IT_HT);
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
// HAL_UART_Receive(&huart2, rxBuffer, 3, HAL_MAX_DELAY);
// HAL_Delay(1000);
// Keyval_Scan();
// __WFI(); // ���ĵȴ�
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
/* USER CODE END 3 */
}
/**
* @brief System Clock Configuration
* @retval None
*/
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
/** Initializes the RCC Oscillators according to the specified parameters
* in the RCC_OscInitTypeDef structure.
*/
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
RCC_OscInitStruct.HSEState = RCC_HSE_ON;
RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV1;
RCC_OscInitStruct.HSIState = RCC_HSI_ON;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL9;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
Error_Handler();
}
/** Initializes the CPU, AHB and APB buses clocks
*/
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
|RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
{
Error_Handler();
}
}
/* USER CODE BEGIN 4 */
// EXTI2�жϴ�������ʵ�֣�
void EXTI2_IRQHandler(void) {
HAL_GPIO_EXTI_IRQHandler(CH452_DOUT_PIN);
}
/* USER CODE END 4 */
/**
* @brief This function is executed in case of error occurrence.
* @retval None
*/
void Error_Handler(void)
{
/* USER CODE BEGIN Error_Handler_Debug */
/* User can add his own implementation to report the HAL error return state */
__disable_irq();
while (1)
{
}
/* USER CODE END Error_Handler_Debug */
}
#ifdef USE_FULL_ASSERT
/**
* @brief Reports the name of the source file and the source line number
* where the assert_param error has occurred.
* @param file: pointer to the source file name
* @param line: assert_param error line source number
* @retval None
*/
void assert_failed(uint8_t *file, uint32_t line)
{
/* USER CODE BEGIN 6 */
/* User can add his own implementation to report the file name and line number,
ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
/* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */
结果：
