stm32单片机串口接收阿里云库函数版

以下是基于阿里云物联网平台提供的 MQTT 协议库函数，在 STM32 单片机上接收串口数据的示例代码：

#include "main.h"
#include "stdio.h"
#include "string.h"
#include "stdlib.h"
#include "stdbool.h"
#include "usart.h"
#include "mqtt_api.h"

#define MQTT_CLIENTID        "DemoDevice"
#define MQTT_USERNAME        "DemoDevice"
#define MQTT_PASSWORD        "DemoDeviceSecret"
#define MQTT_PRODUCTKEY      "a1ABCDEF123"
#define MQTT_DEVICENAME      "demo_device"
#define MQTT_DEVICESECRET    "abcdefg1234567890"

uint8_t mqtt_buf[1024];
uint8_t mqtt_readbuf[1024];
MQTT_ClientTypeDef MQTT_Client;
bool mqtt_connected = false;

void mqtt_connect_cb(void *pClient, int32_t nEvent)
{
    MQTT_ClientTypeDef *client = (MQTT_ClientTypeDef *)pClient;
    switch (nEvent) {
        case MQTT_EVENT_CONNECTED:
            printf("MQTT_EVENT_CONNECTED\n");
            mqtt_connected = true;
            break;
        case MQTT_EVENT_DISCONNECTED:
            printf("MQTT_EVENT_DISCONNECTED\n");
            mqtt_connected = false;
            break;
        default:
            break;
    }
}

void mqtt_message_cb(void *pClient, MQTT_MessageTypeDef *msg)
{
    MQTT_ClientTypeDef *client = (MQTT_ClientTypeDef *)pClient;
    printf("Received Topic: %.*s, Message: %.*s\n", 
            msg->topic_len, msg->ptopic, msg->payload_len, msg->payload);
}

bool mqtt_init(void)
{
    MQTT_Connect_Info connect_info = {0};
    memset(&MQTT_Client, 0x0, sizeof(MQTT_ClientTypeDef));
    connect_info.client_id = MQTT_CLIENTID;
    connect_info.username = MQTT_USERNAME;
    connect_info.password = MQTT_PASSWORD;
    connect_info.keepalive_sec = 60;
    connect_info.clean_session = true;
    connect_info.protocol_version = MQTT_PROTOCOL_VERSION_311;
    connect_info.host = MQTT_PRODUCTKEY ".iot-as-mqtt.cn-shanghai.aliyuncs.com";
    connect_info.port = 1883;
    connect_info.read_buf_size = sizeof(mqtt_readbuf);
    connect_info.write_buf_size = sizeof(mqtt_buf);
    MQTT_Init(&MQTT_Client, mqtt_connect_cb, mqtt_message_cb, &connect_info);
    MQTT_Connect(&MQTT_Client, MQTT_DEVICESECRET, MQTT_DEVICENAME, NULL);
    return true;
}

int main(void)
{
    HAL_Init();
    SystemClock_Config();
    MX_USART1_UART_Init();

    mqtt_init();

    while (1)
    {
        if (mqtt_connected) {
            MQTT_Yield(&MQTT_Client, 1000);
        }
    }
}

这是一个简单的 MQTT 连接示例，其中 `MQTT_Init()` 函数初始化了 MQTT 客户端，而 `mqtt_connect_cb()` 和 `mqtt_message_cb()` 分别是连接和消息回调函数，用于处理连接状态和接收到的消息。

在 `main()` 函数中，我们在初始化串口和 MQTT 客户端之后，不断调用 `MQTT_Yield()` 函数以接收 MQTT 消息。你可以在 `mqtt_message_cb()` 函数中对接收到的消息进行进一步处理。

注意：该示例中的 Aliyun IoT 平台连接信息（如 `MQTT_PRODUCTKEY`、`MQTT_DEVICENAME`、`MQTT_DEVICESECRET` 等）需要替换为你自己的信息。