串口2发送AT指令连接阿里云库函数代码

这是一个基于STM32的串口2发送AT指令连接阿里云的示例代码，你可以根据自己的需求进行修改：

#include "stm32f4xx_hal.h"

UART_HandleTypeDef huart2;

void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_USART2_UART_Init(void);

void Aliyun_Connect(void) {
    char cmd[100];
    HAL_UART_Transmit(&huart2, (uint8_t *) "AT\r\n", 4, 1000);
    HAL_Delay(200);
    HAL_UART_Transmit(&huart2, (uint8_t *) "ATE0\r\n", 6, 1000);
    HAL_Delay(200);
    HAL_UART_Transmit(&huart2, (uint8_t *) "AT+CPIN?\r\n", 10, 1000);
    HAL_Delay(200);
    HAL_UART_Transmit(&huart2, (uint8_t *) "AT+CREG?\r\n", 10, 1000);
    HAL_Delay(200);
    HAL_UART_Transmit(&huart2, (uint8_t *) "AT+CGATT?\r\n", 11, 1000);
    HAL_Delay(200);
    sprintf(cmd, "AT+QIFGCNT=0\r\n");
    HAL_UART_Transmit(&huart2, (uint8_t *) cmd, strlen(cmd), 1000);
    HAL_Delay(200);
    sprintf(cmd, "AT+QICSGP=1,\"CMNET\"\r\n");
    HAL_UART_Transmit(&huart2, (uint8_t *) cmd, strlen(cmd), 1000);
    HAL_Delay(200);
    sprintf(cmd, "AT+QIACT\r\n");
    HAL_UART_Transmit(&huart2, (uint8_t *) cmd, strlen(cmd), 1000);
    HAL_Delay(2000);
    sprintf(cmd, "AT+QMTOPEN=0,\"a1XXXXXXXXX.iot-as-mqtt.cn-shanghai.aliyuncs.com\",1883\r\n");
    HAL_UART_Transmit(&huart2, (uint8_t *) cmd, strlen(cmd), 1000);
    HAL_Delay(2000);
    sprintf(cmd, "AT+QMTCONN=0,\"XXXXXX|securemode=3,signmethod=hmacsha1|\"\r\n");
    HAL_UART_Transmit(&huart2, (uint8_t *) cmd, strlen(cmd), 1000);
    HAL_Delay(2000);
}

int main(void) {
    HAL_Init();
    SystemClock_Config();
    MX_GPIO_Init();
    MX_USART2_UART_Init();
    Aliyun_Connect();
    while (1) {
    }
}

void SystemClock_Config(void) {
    RCC_OscInitTypeDef RCC_OscInitStruct = {0};
    RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
    __HAL_RCC_PWR_CLK_ENABLE();
    __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);
    RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
    RCC_OscInitStruct.HSIState = RCC_HSI_ON;
    RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
    RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
    RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
    RCC_OscInitStruct.PLL.PLLM = 16;
    RCC_OscInitStruct.PLL.PLLN = 336;
    RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV4;
    RCC_OscInitStruct.PLL.PLLQ = 7;
    if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) {
        Error_Handler();
    }
    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_DIV4;
    RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2;
    if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_5) != HAL_OK) {
        Error_Handler();
    }
}

static void MX_USART2_UART_Init(void) {
    huart2.Instance = USART2;
    huart2.Init.BaudRate = 115200;
    huart2.Init.WordLength = UART_WORDLENGTH_8B;
    huart2.Init.StopBits = UART_STOPBITS_1;
    huart2.Init.Parity = UART_PARITY_NONE;
    huart2.Init.Mode = UART_MODE_TX_RX;
    huart2.Init.HwFlowCtl = UART_HWCONTROL_NONE;
    huart2.Init.OverSampling = UART_OVERSAMPLING_16;
    if (HAL_UART_Init(&huart2) != HAL_OK) {
        Error_Handler();
    }
}

static void MX_GPIO_Init(void) {
    __HAL_RCC_GPIOH_CLK_ENABLE();
    __HAL_RCC_GPIOA_CLK_ENABLE();
    GPIO_InitTypeDef GPIO_InitStruct = {0};
    GPIO_InitStruct.Pin = GPIO_PIN_0;
    GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
    HAL_GPIO_Init(GPIOH, &GPIO_InitStruct);
    GPIO_InitStruct.Pin = GPIO_PIN_2 | GPIO_PIN_3;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
    GPIO_InitStruct.Alternate = GPIO_AF7_USART2;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
}

void Error_Handler(void) {
    while (1) {
    }
}

需要注意的是，这里使用的是AT指令连接阿里云，而不是MQTT或者其他协议，如果你需要使用其他协议，请查询阿里云官方文档并修改代码。另外，这里的代码仅供参考，请根据自己的具体情况进行修改和调试。