Keil如何发送AT命令

Question

I am using HC-05 bluetooth module and STM32F407. I am trying to change the name of the bluetooth module. I can enter AT Command Mode, but i can't send any AT Commands to module. I tried something in main . But it didn't work

I see

huart->Instance->DR = (*pData++ & (uint8_t)0xFF);

in my Transmit function. Also, i see ascii values of elements in DR

Here is my try.

/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "string.h"

/* Private variables ---------------------------------------------------------*/
UART_HandleTypeDef huart3;

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_USART3_UART_Init(void);

int main(void)
{
  HAL_Init();
  SystemClock_Config();
  MX_GPIO_Init();
  MX_USART3_UART_Init();
  /* USER CODE BEGIN 2 */
  char* data = "AT+NAME=charles \n\r";
  HAL_UART_Transmit(&huart3, (uint8_t *)data, strlen(data), 2000);
  /* USER CODE END 2 */
  while (1)
  {
  }
}


void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  /** Configure the main internal regulator output voltage 
  */
  __HAL_RCC_PWR_CLK_ENABLE();
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);
  /** Initializes the CPU, AHB and APB busses clocks 
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
  RCC_OscInitStruct.HSIState = RCC_HSI_ON;
  RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }
  /** Initializes the CPU, AHB and APB busses clocks 
  */
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK)
  {
    Error_Handler();
  }
}

static void MX_USART3_UART_Init(void)
{

  huart3.Instance = USART3;
  huart3.Init.BaudRate = 38400;
  huart3.Init.WordLength = UART_WORDLENGTH_8B;
  huart3.Init.StopBits = UART_STOPBITS_1;
  huart3.Init.Parity = UART_PARITY_NONE;
  huart3.Init.Mode = UART_MODE_TX_RX;
  huart3.Init.HwFlowCtl = UART_HWCONTROL_NONE;
  huart3.Init.OverSampling = UART_OVERSAMPLING_16;
  if (HAL_UART_Init(&huart3) != HAL_OK)
  {
    Error_Handler();
  }
}


static void MX_GPIO_Init(void)
{
  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOB_CLK_ENABLE();
}


  [1]: https://i.stack.imgur.com/pbxqx.png

Answer 1

If you want to send a character buffer:

static void MX_USART3_UART_Init(void)
{
   char* data = "AT+NAME=charles \n\r";
   HAL_UART_Transmit(&huart3, (uint8_t *)data, strlen(data), 2000);
}

That's all you need. You called sprintf as if it was strcpy and the first argument is an uninitialized character buffer.

Answer 2

as tadman said, you don't need this:

uint8_t data[50];

But this is not a uninitialized character buffer as tadman said.