STM32-ESP8266通过MQTT与阿里云通讯
嫌文字看着累的话,直接搜账号名嵌入式crafter(小破站 / 某音 / 某红书同号),视频里把讲解的内容和实战操作揉在一起了,比对着文档啃效率高多了。
2.1.AT指令(ESP8266-MQTT)
AT+CWJAP:配置WIFI
#define ESP8266_WIFI_INFO "AT+CWJAP=\"360\",\"02744871\"\r\n" //连接的Wifi名 密码
AT+MQTTUSERCFG:设置MQTT用户参数
第一个空username:stm32_esp8266&k1h2hHKWDOX
第二个空passwd:a7ff9d1d6f5c116ad1c6ce9385214c85372188c3d68d66f2fa571aa2609fd2f6
#define MQTTUSERCFG "AT+MQTTUSERCFG=0,1,\"NULL\",\"stm32_esp8266&k1h2hHKWDOX\",\"a7ff9d1d6f5c116ad1c6ce9385214c85372188c3d68d66f2fa571aa2609fd2f6\",0,0,\"\"\r\n"
AT+MQTTCLIENTID:设置MQTT ID
需要在securemode=2之后加\\,以及hmacsha256之后加\\
#define MQTTCLIENTID "AT+MQTTCLIENTID=0,\"k1h2hHKWDOX.stm32_esp8266|securemode=2\\,signmethod=hmacsha256\\,timestamp=1752204377503|\"\r\n"
发送AT+MQTTCONN=0,"域名",1883,1
添加图片注释,不超过 140 字(可选)
#define MQTTCONN "AT+MQTTCONN=0,\"iot-06z00jlxn39wea0.mqtt.iothub.aliyuncs.com\",1883,1\r\n"
如果一直连接不上
刷新云平台页面得到最新的passwd和clientld,进行多次尝试,每修改一次passwd也要跟着修改clientid。
2.2.STM32Cubemx串口配置
根据前一章(平台链接),我们可知esp8266通过串口与STM32进行连接。我们来看一下STM32Cubemx的配置。
打开中断
#include "usart.h"extern UART_HandleTypeDef huart3;
extern unsigned char esp8266_buf[512];
extern unsigned short esp8266_cnt, esp8266_cntPre;
uint8_t receivedByte2;void setup_uart_interrupt()
{HAL_UART_Receive_IT(&huart3, &esp8266_buf[0], 1);
}void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{unsigned int timeout=0;unsigned int maxDelay=0x1FFFF;if(huart->Instance == USART3){while(HAL_UART_GetState(&huart3) != HAL_UART_STATE_READY)//等待就绪{timeout++;//超时处理if(timeout > maxDelay) break; }timeout=0;while(HAL_UART_Receive_IT(&huart3, &receivedByte2, 1)!=HAL_OK){timeout++; //超时处理if(timeout > maxDelay) break; }if(esp8266_cnt >= sizeof(esp8266_buf)) esp8266_cnt = 0; //防止串口被刷爆esp8266_buf[esp8266_cnt++] = receivedByte2;}
}
2.3.STM32连接阿里云代码
#include "esp8266_mqtt.h"/* MQTT参数配置 *//* 连接WIFI */
#define ESP8266_WIFI_INFO "AT+CWJAP=\"TD\",\"TD13502744871\"\r\n"
/* MQTT参数:username passwd */
#define MQTTUSERCFG "AT+MQTTUSERCFG=0,1,\"NULL\",\"stm32_esp8266&k1h2hHKWDOX\",\"2a1b2c9fc4edc45103a2985ce4c3cd0ea07f0953649b9a2ef2238e92224dc909\",0,0,\"\"\r\n"
/* MQTT参数:clientId */
#define MQTTCLIENTID "AT+MQTTCLIENTID=0,\"k1h2hHKWDOX.stm32_esp8266|securemode=2\\,signmethod=hmacsha256\\,timestamp=1752205360361|\"\r\n"
#define STM32_RECEIVE_TOPIC "AT+MQTTSUB=0,\"/k1h2hHKWDOX/stm32_esp8266/user/Receive\",1\r\n"
/* MQTT参数:mqttHostUrl */
#define MQTTCONN "AT+MQTTCONN=0,\"iot-06z00jlxn39wea0.mqtt.iothub.aliyuncs.com\",1883,1\r\n"/* 串口usart,esp8266数据处理 */
extern UART_HandleTypeDef huart3;
#define ESP8266_USART &huart3
unsigned char esp8266_buf[512];
unsigned short esp8266_cnt = 0, esp8266_cntPre = 0;/* 光强和温湿度buffer */
extern float Light_Value;
extern unsigned int rec_data[4];/*
************************************************************
* 函数名称: Usart_SendString
*
* 函数功能: 串口数据发送
*
* 入口参数: USARTx:串口组
* str:要发送的数据
* len:数据长度
*
* 返回参数: 无
*
* 说明:
************************************************************
*/
void Usart_SendString(UART_HandleTypeDef *USARTx, unsigned char *str, unsigned short len)
{unsigned short count = 0;if (str == NULL || USARTx == NULL) {return;}for (; count < len; count++) {if (str[count] == '\0') {break;}HAL_UART_Transmit(USARTx, (uint8_t *)(str + count), 1, 10);}
}//==========================================================
// 函数名称: ESP8266_Clear
//
// 函数功能: 清空缓存
//
// 入口参数: 无
//
// 返回参数: 无
//
// 说明:
//==========================================================
void ESP8266_Clear(void)
{memset(esp8266_buf, 0, sizeof(esp8266_buf));esp8266_cnt = 0;}//==========================================================
// 函数名称: ESP8266_WaitRecive
//
// 函数功能: 等待接收完成
//
// 入口参数: 无
//
// 返回参数: REV_OK-接收完成 REV_WAIT-接收超时未完成
//
// 说明: 循环调用检测是否接收完成
//==========================================================
_Bool ESP8266_WaitRecive(void)
{if(esp8266_cnt == 0) //如果接收计数为0 则说明没有处于接收数据中,所以直接跳出,结束函数return REV_WAIT;if(esp8266_cnt == esp8266_cntPre) //如果上一次的值和这次相同,则说明接收完毕{esp8266_cnt = 0; //清0接收计数return REV_OK; //返回接收完成标志}esp8266_cntPre = esp8266_cnt; //置为相同return REV_WAIT; //返回接收未完成标志
}//==========================================================
// 函数名称: ESP8266_SendCmd
//
// 函数功能: 发送命令
//
// 入口参数: cmd:命令
// res:需要检查的返回指令
//
// 返回参数: 0-成功 1-失败
//
// 说明:
//==========================================================
_Bool ESP8266_SendCmd(char *cmd, char *res)
{unsigned char timeOut = 200;printf("\r\nWifiTx = %s\n", cmd);HAL_UART_Transmit(&huart3, (uint8_t *)cmd, strlen((const char *)cmd), 0xffff);while(timeOut--){if(ESP8266_WaitRecive() == REV_OK) //如果收到数据{//printf("esp8266_buf : %s\n", esp8266_buf);if(strstr((const char *)esp8266_buf, res) != NULL) //如果检索到关键词{ESP8266_Clear(); //清空缓存return 0;}}HAL_Delay(10);}return 1;
}//==========================================================
// 函数名称: ESP8266_SendData
//
// 函数功能: 发送数据
//
// 入口参数: data:数据
// len:长度
//
// 返回参数: 无
//
// 说明:
//==========================================================
void ESP8266_SendData(unsigned char *data, unsigned short len)
{char cmdBuf[32];ESP8266_Clear(); //清空接收缓存sprintf(cmdBuf, "AT+CIPSEND=%d\r\n", len); //发送命令if(!ESP8266_SendCmd(cmdBuf, ">")) //收到‘>’时可以发送数据{//Usart_SendString(ESP8266_USART, data, len); //发送设备连接请求数据HAL_UART_Transmit(&huart3, (uint8_t *)data, len, 0xffff);}
}//==========================================================
// 函数名称: ESP8266_GetIPD
//
// 函数功能: 获取平台返回的数据
//
// 入口参数: 等待的时间(乘以10ms)
//
// 返回参数: 平台返回的原始数据
//
// 说明: 不同网络设备返回的格式不同,需要去调试
// 如ESP8266的返回格式为 "+IPD,x:yyy" x代表数据长度,yyy是数据内容
//==========================================================
unsigned char *ESP8266_GetIPD(unsigned short timeOut)
{char *ptrIPD = NULL;do{if(ESP8266_WaitRecive() == REV_OK) //如果接收完成{printf("%s\n", esp8266_buf);ptrIPD = strstr((char *)esp8266_buf, "+MQTTSUBRECV:"); //搜索“IPD”头if(ptrIPD != NULL) //如果没找到,可能是IPD头的延迟,还是需要等待一会,但不会超过设定的时间{ptrIPD = strchr(ptrIPD, '{'); //找到':'if(ptrIPD != NULL){return (unsigned char *)(ptrIPD);}}}HAL_Delay(1); //延时等待} while(timeOut--);ESP8266_Clear();return NULL; //超时还未找到,返回空指针
}//==========================================================
// 函数名称: ESP8266_Init
//
// 函数功能: 初始化ESP8266
//
// 入口参数: 无
//
// 返回参数: 无
//
// 说明:
//==========================================================
void ESP8266_Init(void)
{uint8_t log_line = 32;HAL_Delay(500);ESP8266_Clear();ESP8266_SendCmd("AT+RST\r\n", "OK");printf("1. AT\r\n");while(ESP8266_SendCmd("AT\r\n", "OK")) {HAL_Delay(500);printf("Sending AT command failed, retrying...\r\n"); }LCD_print_log(0, log_line*0, (uint8_t *)"1.AT");printf("2. CWMODE\r\n");while(ESP8266_SendCmd("AT+CWMODE=1\r\n", "OK")) //配置为STA模式{HAL_Delay(500);printf("Setting CWMODE failed, retrying...\r\n");}LCD_print_log(0, log_line*1, (uint8_t *)"2.AT+CWMODE");printf("3. AT+CIPSNTPCFG\r\n");while(ESP8266_SendCmd("AT+CIPSNTPCFG=1,8,\"cn.ntp.org.cn\",\"ntp.sjtu.edu.cn\"\r\n", "OK")) {HAL_Delay(500);printf("Setting CWDHCP failed, retrying...\r\n");}LCD_print_log(0, log_line*2, (uint8_t *)"3.AT+CIPSNTPCFG");printf("4. CWJAP\r\n");while(ESP8266_SendCmd(ESP8266_WIFI_INFO, "GOT IP")) {HAL_Delay(500);printf("Connecting to WiFi failed, retrying...\r\n");}LCD_print_log(0, log_line*3, (uint8_t *)"4.AT+CWJAP");//设备名、密码printf("5.AT+MQTTUSERCFG\r\n");while(ESP8266_SendCmd(MQTTUSERCFG, "OK")) {HAL_Delay(500);//printf("Starting TCP connection failed, retrying...\r\n");}LCD_print_log(0, log_line*4, (uint8_t *)"5.AT+MQTTUSERCFG");printf("6.AT+MQTTCLIENTID\r\n");while(ESP8266_SendCmd(MQTTCLIENTID, "OK")) {HAL_Delay(500);//printf("Starting TCP connection failed, retrying...\r\n");}LCD_print_log(0, log_line*5, (uint8_t *)"6.AT+MQTTCLIENT");printf("7.AT+MQTTCONN\r\n");while(ESP8266_SendCmd(MQTTCONN, "OK")) {HAL_Delay(500);printf("MQTTCONN failed, retrying...\r\n");}LCD_print_log(0, log_line*6, (uint8_t *)"7.AT+MQTTCONN");LCD_Clear(WHITE); //清屏printf("8.AT+MQTTSUB\r\n");while(ESP8266_SendCmd(STM32_RECEIVE_TOPIC, "OK")){HAL_Delay(500);printf("MQTTSUB failed, retrying...\r\n");}LCD_print_log(0, log_line*0, (uint8_t *)"8.AT+MQTTSUB");LCD_print_log(0, log_line*1, (uint8_t *)"Cloud connected"); printf("Cloud connection successful\n");
}void Get_Data_From_Cloud(void)
{unsigned char *data = ESP8266_GetIPD(200);if (data != NULL) {// 处理接收到的数据,例如:printf("Received data: %s\n", data);// 根据需要解析 JSON 数据cJSON *json = cJSON_Parse((char *)data);if (json != NULL) {// 解析并处理 LED 数据cJSON *led = cJSON_GetObjectItem(json, "LED");if (cJSON_IsNumber(led)) {printf("LED: %d\n", led->valueint);LED_TOGGLE(1);//在这里处理 LED 数据} else {printf("Error: LED is not a number\n");}// 解析并处理 door 数据cJSON *door = cJSON_GetObjectItem(json, "door");if (cJSON_IsNumber(door)) {printf("door: %d\n", door->valueint);Toggle_Door();// 在这里处理 door 数据} else {printf("Error: door is not a number\n");}// 解析并处理 beep 数据cJSON *beep = cJSON_GetObjectItem(json, "beep");if (cJSON_IsNumber(beep)) {printf("beep: %d\n", beep->valueint);BEEP_TOGGLE(1,100);// 在这里处理 beep 数据} else {printf("Error: beep is not a number\n");}cJSON_Delete(json);} else {printf("Error: Failed to parse JSON\n");}} else {//printf("Error: No data received\n");}
}void Send_Data_To_Cloud(void)
{char buf[256];int i = 0;if(rec_data[2] > 0 && rec_data[2] <=200){//自定义云产品转发上传主题sprintf(buf, "AT+MQTTPUB=0,\"/k1h2hHKWDOX/stm32_esp8266/user/Send\",\"{\\\"params\\\":{\\\"Temp\\\":%d}}\",1,0\r\n", rec_data[2]);printf("WifiTx = %s", buf);//ESP8266_SendCmd(buf, NULL);HAL_UART_Transmit(&huart3, (uint8_t *)buf, strlen((const char *)buf), 0xffff);memset(buf, 0, sizeof(buf));ESP8266_Clear(); //清空缓存HAL_Delay(100);}if(rec_data[0] > 0 && rec_data[0] <=200){sprintf(buf, "AT+MQTTPUB=0,\"/k1h2hHKWDOX/stm32_esp8266/user/Send\",\"{\\\"params\\\":{\\\"Humi\\\":%d}}\",1,0\r\n", rec_data[0]);printf("WifiTx = %s", buf);//ESP8266_SendCmd(buf, NULL);HAL_UART_Transmit(&huart3, (uint8_t *)buf, strlen((const char *)buf), 0xffff);memset(buf, 0, sizeof(buf));ESP8266_Clear(); //清空缓存HAL_Delay(100);}if(Light_Value > 0 && Light_Value <=200){sprintf(buf, "AT+MQTTPUB=0,\"/k1h2hHKWDOX/stm32_esp8266/user/Send\",\"{\\\"params\\\":{\\\"light\\\":%d}}\",1,0\r\n", (uint8_t)Light_Value);printf("WifiTx = %s", buf);//ESP8266_SendCmd(buf, NULL);HAL_UART_Transmit(&huart3, (uint8_t *)buf, strlen((const char *)buf), 0xffff);memset(buf, 0, sizeof(buf));ESP8266_Clear(); //清空缓存HAL_Delay(100);}
}
2.4.连接成功展示
连接成功后会显示设备在线
订阅成功topic后,设备下topic列表才会显示。
添加图片注释,不超过 140 字(可选)