博客

一、ESP8266模块

1.模块介绍

本项目无线通讯模块使用的是WiFi模块ESP8266，乐鑫公司推出的高性能、低功耗串口WiFi模块ESP8266应该是使用最广泛的一种WIFI模块之一了，它自身带有高性能的MCU（Microcontroller Unit），因此它既可以通过串口连接为外部MCU提供 WiFi通信功能，也就是我们本项目所用到的功能；当然它也可以让用户直接在模块内置的MCU上基于RTOS SDK进行软件编程，开发出具有低功耗、低成本的WiFi连接产品，如市面上大部分WiFi智能插座就用了ESP8266模块和它的这一功能。

ESP8266内置一个Tensilica(泰思立达)Xtensa架构的32位处理器L106,具有5级流水线(ARM CortexM3是3级流水线)，最大时钟速度为160MHz，可以使用高达16MB的外部SPI Flash。该模块采用串口与MCU(或其他串口设备）通信，内置 TCP/IP协议栈，能够实现串口与 WiFi之间的转换。通过该模块，传统的串口设备只需要简单的串口配置，即可通过WiFi传输自己的数据。

WiFi具有两种功能模式:一种叫AP(Access Point)模式，一种叫Station模式。AP就是我们平时所说的热点，如无线路由器，开了热点的手机等，这些AP设备可以允许其他设备(如手机，PC等)输入热点名(SSID)和密码(也可不设置密码)后连接上网；Station模式则是前面说的连接AP的设备(如手机，PC等)。

ESP8266除支持上述两种模式以外，还可以支持第三种模式:AP+Station，即:将AP和Station的功能合二为一，它主要是实现无线桥接的功能，该模式应用的场景不多。

STM32单片机在与ESP8266进行串口通信时采用AT命令进行通信，这样想要做ESP8266 WiFi模块的程序开发的话，那我们首先得学习并熟练掌握ESP8266 WiFi模块的AT指令。

2.AT指令介绍

AT指令是以AT作为开头，\r\n字符结束的字符串，每个指令执行成功与否都有相应的返回。其他的一些非预期的信息(如有人拨号进来、线路无信号等)，模块将有对应的一些信息提示，接收端可做相应的处理。

不同模块的AT命令可能不一样的，这要对着模块的AT指令手册来查看。

AT命令可分为四类：

2.硬件连接

由于我的开发板当中3.3V电源是LDO电路从USB TypeC接口提供的5V降压而来，电流较低，所以连ESP8266模块可能会导致它不能正常工作，所以这里我连了5V做VCC，而我所用的ESP8266能够正常工作，具体所用的时候可以视情况而定。




提示：USB3.0的接口电流较高，如果必要用5V，最好不用USB3.0


ESP8266模块提供TTL串口通信接口，而我所使用的开发板上的扩展UART2串口也是TTL电平，所以直接连接如下：

二、串口转发及调试

1.串口转发流程

开发板的USART2串口连接了ESP8266模块，当然我们要通过PC来对它进行调试，所以我们需要STM32写一个单片机上写一个串口接收转发的程序如下图：

2.串口转发程序实现

STM32CubeMX配置

修改usart.h/.c文件

对usart.h文件做如下修改：

... ...
/* USER CODE BEGIN Private defines */
extern char g_uart1_rxbuf[256];
extern uint8_t g_uart1_bytes;


#define clear_uart1_rxbuf() do { memset(g_uart1_rxbuf, 0, sizeof(g_uart1_rxbuf)); \
		g_uart1_bytes=0; } while(0)

//在这里添加uar2接收 buffer相关变量声明，并添加一个宏 clear_uart2_rxbuf()用来清除接收 buffer里的数据
extern char g_uart2_rxbuf[256];
extern uint8_t g_uart2_bytes;


#define clear_uart2_rxbuf() do { memset(g_uart2_rxbuf, 0, sizeof(g_uart2_rxbuf)); \
		g_uart2_bytes=0; } while(0)

//添加串口接收转发函数的声明
extern void uart_forward(void);

/* USER CODE END Private defines */
... ...

对usart.c文件做如下修改：

... ...
/* USER CODE BEGIN 0 */
static	uint8_t			s_uart1_rxch;
char					g_uart1_rxbuf[256];
uint8_t					g_uart1_bytes;

static	uint8_t			s_uart2_rxch;
char					g_uart2_rxbuf[256];
uint8_t					g_uart2_bytes;
/* USER CODE END 0 */
... ...

void MX_USART2_UART_Init(void)
{
... ...
  /* USER CODE BEGIN USART2_Init 2 */
  HAL_UART_Receive_IT(&huart2 , &s_uart2_rxch, 1);//HAL_UART_Receive_IT中断服务处理程序
  /* USER CODE END USART2_Init 2 */

}
... ...

/* USER CODE BEGIN 1 */
void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{
	if (huart->Instance == USART1)
	{
		if( g_uart1_bytes< sizeof(g_uart1_rxbuf) )
		{
			g_uart1_rxbuf[g_uart1_bytes++] = s_uart1_rxch;
		}
		HAL_UART_Receive_IT(&huart1 , &s_uart1_rxch, 1);
	}

	if (huart->Instance == USART2)
		{
			if( g_uart2_bytes< sizeof(g_uart2_rxbuf) )
			{
				g_uart2_rxbuf[g_uart2_bytes++] = s_uart2_rxch;
			}
			HAL_UART_Receive_IT(&huart2 , &s_uart2_rxch, 1);
		}
}

//添加usart1和usart2的收发转发功能函数，main()函数中调用
void uart_forward(void)
{
	if(strstr(g_uart1_rxbuf, "\r\n"))
	{
		HAL_UART_Transmit(&huart2, (uint8_t *)g_uart1_rxbuf, g_uart1_bytes,0xFF);
		clear_uart1_rxbuf();
	}

	if(g_uart2_bytes > 0)
	{
		HAL_Delay(100);/*Wait AT command reply receive over*/
		HAL_UART_Transmit(&huart1, (uint8_t *)g_uart2_rxbuf, g_uart2_bytes,0xFF);
		clear_uart2_rxbuf();
	}
}
... ...

/* USER CODE END 1 */

... ...

修改main.c文件

如下：

... ...
  while(1)
  {
	  uart_forward();//后面使用无线通讯时只需要用Socket通信，不在需要此转发程序，如果没有注释掉会报错，并不会执行PC发的JOSN指令
#if 0
... ...
#endif
    /* USER CODE END WHILE */

    /* USER CODE BEGIN 3 */
    }... ...
    

3.运行测试

用串口调试工具进行测试：

三、AT指令学习

每一个使用AT指令通信的模块都有自己详细的AT指令使用说明文档，模块里的软件固件版本不一样，其AT指令可能也不大一样，可以通过你的模块以及版本找到对应的说明文档对照。

对于我所使用的ESP8266 WiFi模块：

1.WiFi初始化命令

2.无线连接命令

3.数据收发命令


注意：指令带_CUR后缀则表示只更改当前系统配置，并不写入Flash存储器中，重启复位后失效。而如果需要重启后依然有效则用带_DEF后缀的命令。


四、WiFi模块实时上报温湿度与远程控制LED灯实现

1.esp8266.h/.c

代码如下：

/*
 * esp8266.h
 *
 *  Created on: 2023年2月26日
 *      Author: ASUS
 */

#ifndef INC_ESP8266_H_
#define INC_ESP8266_H_

#include <stdio.h>

#define wifi_huart			&huart2			/*wiFi模块使用的串口*/
#define g_wifi_rxbuf		g_uart2_rxbuf	/*wiFi模块的接收buffer */
#define g_wifi_rxbytes		g_uart2_bytes 	/*wiFi模块接收的数据大小*/

/*清除WiFi模块接收 buffer里的数据内容宏，用宏不用函数是因为函数调用需要额外时间开销*/
#define clear_atcmd_buf()	do { memset(g_wifi_rxbuf, 0, sizeof(g_wifi_rxbuf));g_wifi_rxbytes=0; } while(0)

/*ESP8266 WiFi模块发送AT命令函数，返回值为О表示成功，!0表示失败*/
#define EXPECT_OK	"OK\r\n"
extern int send_atcmd(char *atcmd, char *expect_reply, unsigned int timeout);

/*ESP8266 WiFi模块初始化函数。返回值为0表示成功，!0表示失败*/
extern int esp8266_module_init(void);

/*ESP8266 WiFi模块复位重启函数。返回值为О表示成功，!0表示失败*/
extern int esp8266_module_reset(void);

/*ESP8266 WiFi模块连接路由器函数。返回值为О表示成功，!0表示失败*/
extern int esp8266_join_network( char *ssid,char *pwd) ;

/*ESP8266获取自己的IP地址和网关IP地址。返回值为О表示成功，!O表示失败*/
int esp8266_get_ipaddr(char *ipaddr, char *gateway, int ipaddr_size);

/*ESP8266 WiFi模块做ping 命令测试网络连通性。返回值为О表示成功，!0表示失败*/
int esp8266_ping_test(char *host);

/*ESP8266 WiFi模块建立TCP socket连接函数。返回值为О表示成功，!0表示失败*/
extern int esp8266_sock_connect( char *servip, int port);

/* ESP8266 WiFi模块断开TCP socket连接函数。返回值为О表示成功，!0表示失败*/
extern int esp8266_sock_disconnect(void);

/*ESP8266 WiFi通过 TCP Socket发送数据函数。返回值为0表示失败，>0表示成功发送字节数*/
extern int esp8266_sock_send(unsigned char *data, int bytes);

/* ESP8266 WiFi通过TCP Socket 接收数据函数。返回值为0无数据，>0表示接收到数据字节数*/
extern int esp8266_sock_recv(unsigned char *buf, int size);

#endif /* INC_ESP8266_H_ */

/*
 * esp8266.c
 *
 *  Created on: 2023年2月26日
 *      Author: ASUS
 */

#include <stdlib.h>
#include "usart.h"
#include "esp8266.h"

/*WiFi模块驱动调试宏,注释下面两个宏定义可以取消调试打印*/
//#define CONFIG_WIFI_DEBUG
#define CONFIG_WIFI_PRINT

#ifdef CONFIG_WIFI_DEBUG
#define wifi_dbg(format,args...) printf(format, ##args)
#else
#define wifi_dbg(format,args...) do{} while(0)
#endif

#ifdef CONFIG_WIFI_PRINT
#define wifi_print(format,args...) printf(format, ##args)
#else
#define wifi_print(format,args...) do{} while(0)
#endif

int send_atcmd(char *atcmd, char *expect_reply, unsigned int timeout)
{
	int				rv = 1;
	unsigned int	i;
	char			*expect;

	/*check function input arguments validation*/
	if( !atcmd || strlen(atcmd)<=0 )
	{
		wifi_print("ERROR:Invalid input arguments\r\n");
		return -1;
	}

	wifi_dbg("\r\nStart send AT command: %s",atcmd);
	clear_atcmd_buf();
	HAL_UART_Transmit(wifi_huart, (uint8_t *)atcmd, strlen(atcmd), 1000);

	expect = expect_reply ? expect_reply : "OK\r\n";

	/*Receive AT reply string by UART interrupt handler，stop by "OK/ERROR" or timeout*/
	for(i=0; i<timeout; i++)
	{
		if( strstr(g_wifi_rxbuf, expect))
		{
			wifi_dbg("AT command Got expect reply '%s'\r\n", expect);
			rv = 0;
			goto CleanUp;
		}
		if( strstr(g_wifi_rxbuf, "ERROR\r\n") || strstr(g_wifi_rxbuf, "FAIL\r\n"))
		{
			rv = 2;
			goto CleanUp;
		}

		HAL_Delay(1);
	}


CleanUp:
	wifi_dbg("<<<< AT command reply:\r\n%s", g_wifi_rxbuf);
	return rv;

}

int atcmd_send_data(unsigned char *data, int bytes, unsigned int timeout)
{
	int				rv = -1;
	unsigned int	i;

	/* check function input arguments validation */
	if( !data || bytes <= 0 )
	{
		wifi_print("ERROR: Invalid input arguments\r\n");
		return -1;
	}

	wifi_dbg("\r\nStart AT command send [%d] bytes data\n", bytes);
	clear_atcmd_buf();
	HAL_UART_Transmit(wifi_huart, data, bytes, 1000);

	/*Receive AT reply string by UART interrupt handler，stop by "OK/ERROR" or timeout */
	for(i=0; i<timeout; i++)
	{
		if(strstr(g_wifi_rxbuf, "SEND OK\r\n"))
		{
			rv = 0;
			goto CleanUp;
		}
		if(strstr(g_wifi_rxbuf, "ERROR\r\n"))
		{
			rv = 1;
			goto CleanUp;
		}

		HAL_Delay(1);
	}


CleanUp:
	wifi_dbg("<<<< AT command reply:\r\n%s", g_wifi_rxbuf);
	return rv;
}

int esp8266_module_init(void)
{
	int		i;

	wifi_print("INFO: Reset ESP8266 module now...\r\n");
	send_atcmd("AT+RST\r\n", EXPECT_OK, 500);

	for(i=0; i<6; i++)
	{
		if( !send_atcmd("AT\r\n", EXPECT_OK, 500) )
		{
			wifi_print("INFO: Send AT to ESP8266 and got reply ok \r\n");
			break;
		}

		HAL_Delay(100);
	}

	if( i>= 6 )
	{
		wifi_print("ERROR: Can't receive AT replay after reset\r\n");
		return -2;
	}

	if( send_atcmd( "AT+CWMODE=1\r\n", EXPECT_OK, 500) )
	{
		wifi_print("ERROR : Set ESP8266 work as station mode failure\r\n");
		return -3;
	}

	if( send_atcmd("AT+CWDHCP=1,1\r\n", EXPECT_OK, 500) )
	{
		wifi_print("ERROR: Enable ESP8266 Station mode DHCP failure\r\n");
		return -4;
	}

#if 0
	if( send_atcmd( "AT+GMR\r\n",EXPECT_OK，500))
	{
		wifi_print("ERROR: AT+GMR check ESP8266 reversion failure\r\n");
		return -5;
	}
#endif
	HAL_Delay(500);
	return 0;
}


int esp8266_join_network(char *ssid, char *pwd)
{
	char			atcmd[128] = {0x00};
	int				i;

	if( !ssid || !pwd )
	{
		wifi_print( "ERROR:Invalid input arguments\r\n");
		return -1;
	}

	snprintf(atcmd, sizeof(atcmd), "AT+CWJAP=\"%s\",\"%s\"\r\n", ssid, pwd);
	if( send_atcmd(atcmd, "CONNECTED", 10000) )
	{
		wifi_print("ERROR: ESP8266 connect to '%s' failure\r\n", ssid);
		return -2 ;
	}
	wifi_print("INFO: ESP8266 connect to '%s' ok\r\n", ssid);

	/*check got IP address or not by netmask (255.)*/
	for(i=0; i<10; i++)
	{
		if( !send_atcmd( "AT+CIPSTA_CUR?\r\n", "255.", 1000))
		{
			wifi_print( "INFO: ESP8266 got Ip address ok\r\n" );
			return 0;
		}

		HAL_Delay(300);
	}

	wifi_print("ERROR: ESP8266 assigned IP address failure\r\n");
	return -3;
}

/*
+CIPSTA_CUR:ip: "192.168.0.120"
+CIPSTA_CUR:gateway: "192.168.0.1"
*/
static int util_parser_ipaddr(char *buf, char *key, char *ipaddr, int size)
{
	char		*start;
	char		*end;
	int			len;

	if(!buf || !key || !ipaddr)
	{
		return -1;
	}
	/*find the key string */
	start = strstr(buf, key);
	if( !start )
	{
		return -2;
	}

	start+=strlen(key) + 1;/*Skip ”*/
	end = strchr(start,'"');/*find last " */
	if( !end )
	{
		return -3;
	}

	len = end - start;
	len = len>size ? size : len;

	memset(ipaddr, 0, size);
	strncpy(ipaddr, start, len);

	return 0;
}

int esp8266_get_ipaddr(char *ipaddr, char *gateway, int ipaddr_size)
{
	if( !ipaddr || !gateway || ipaddr_size<7 )
	{
		wifi_print("ERROR: Invalid input arguments\r\n");
		return -1;
	}

	if( send_atcmd( "AT+CIPSTA_CUR?\r\n", "255.", 1000) )
	{
		wifi_print("ERROR: ESP8266 AT+CIPSTA_CUR? command failure\r\n");
		return -2;
	}

	if( util_parser_ipaddr(g_wifi_rxbuf, "ip:", ipaddr, ipaddr_size) )
	{
		wifi_print("ERROR: ESP8266 AT+CIPSTA_CUR? parser IP address failure\r\n");
		return -3;
	}

	if( util_parser_ipaddr(g_wifi_rxbuf, "gateway:", gateway, ipaddr_size))
	{
		wifi_print("ERROR: ESP8266 AT+CIPSTA_CUR? parser gateway failure\r\n");
		return -4;
	}

	wifi_print("INFO: ESP8266 got IP address[%s] gateway[%s] ok\r\n", ipaddr, gateway);
	return 0;
}

int esp8266_ping_test(char *host)
{
	char			atcmd[128]={0x00};

	if(!host)
	{
		wifi_print( "ERROR: Invalid input arguments\r\n" );
		return -1;
	}

	snprintf(atcmd, sizeof(atcmd), "AT+PING=\"%s\"\r\n", host);
	if( send_atcmd( atcmd, EXPECT_OK, 3000) )
	{
		wifi_print("ERROR: ESP8266 ping test [%s ] failure\rin", host);
		return -2;
	}

	wifi_print("INFO: ESP8266 ping test [%s ] ok\r\n", host);
	return 0;
}

int esp8266_sock_connect(char *servip, int port)
{
	char			atcmd[128] = {0x00};

	if( !servip || port<=0 )
	{
		wifi_print("ERROR: Invalid input arguments\rin");
		return -1;
	}

	send_atcmd ( "AT+CIPMUX=0\r\n", EXPECT_OK, 1500);

	snprintf(atcmd, sizeof(atcmd), "AT+CIPSTART=\"TCP\",\"%s\",%d\r\n", servip, port);
	if(send_atcmd(atcmd,"CONNECT\r\n", 1000) )
	{
		wifi_print("ERROR: ESP8266 socket connect to [%s:%d] failure\r\n", servip, port);
		return -2;
	}

	wifi_print("INFO: ESP8266 socket connect to [%s:%d] ok\r\n", servip, port);
	return 0;
}

int esp8266_sock_disconnect(void)
{
	send_atcmd("AT+CIPCLOSE\r\n", EXPECT_OK, 1500);
	return 0;
}

int esp8266_sock_send(unsigned char *data, int bytes)
{
	char			atcmd[128] = {0x00};

	if( !data || bytes<=0)
	{
		wifi_print("ERROR: Invalid input arguments\r\n");
		return -1;
	}

	snprintf(atcmd, sizeof(atcmd),  "AT+CIPSEND=%d\r\n", bytes);
	if( send_atcmd(atcmd, ">", 500))
	{
		wifi_print("ERROR: AT+CIPSEND command failure\rin");
		return 0;
	}

	if( atcmd_send_data((unsigned char *)data, bytes, 1000))
	{
		wifi_print("ERROR: AT+CIPSEND send data failure\r\n");
		return 0;
	}

	return bytes;
}

int esp8266_sock_recv( unsigned char *buf, int size)
{
	char			*data = NULL;
	char			*ptr = NULL;

	int				len;
	int				rv;
	int				bytes;

	if( !buf || size <= 0)
	{
		wifi_print("ERROR: Invalid input arguments\r\n");
		return -1;
	}

	if( g_wifi_rxbytes <= 0 )
	{
		return 0;
	}

	/*No data arrive or not integrated */
	if( !(ptr=strstr(g_wifi_rxbuf, "+IPD,")) || !(data=strstr( ptr, ":")) )
	{
		return 0;
	}

	data++;
	bytes = atoi(ptr+strlen("+IPD,"));

	len = g_wifi_rxbytes - (data-g_uart2_rxbuf);

	if( len < bytes )
	{
		wifi_dbg("+IPD data not receive over, receive again later ...\r\n");
		return 0;
	}

	memset(buf, 0, size);
	rv = bytes>size ? size : bytes;
	memcpy(buf, data, rv);

	clear_atcmd_buf();

	return rv;
}

2.main.c

代码如下：

/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.c
  * @brief          : Main program body
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; Copyright (c) 2022 STMicroelectronics.
  * All rights reserved.</center></h2>
  *
  * This software component is licensed by ST under BSD 3-Clause license,
  * the "License"; You may not use this file except in compliance with the
  * License. You may obtain a copy of the License at:
  *                        opensource.org/licenses/BSD-3-Clause
  *
  ******************************************************************************
  */
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "adc.h"
#include "tim.h"
#include "usart.h"
#include "gpio.h"

/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include <string.h>
#include <stdio.h>
#include "dht11.h"
#include "sht30.h"
#include "core_json.h"
#include "oled.h"
#include "esp8266.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 */
#define FLAG_WIFI_CONNECTED		(1<<0)	/* WiFi连接路由器标志位*/
#define FLAG_SOCK_CONNECTED 	(1<<1)  /* Socket连接服务器标志位*/
/* 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 */
static int report_tempRH_json(void);
static int parser_led_json(char *json_string, int bytes);
static void proc_uart1_recv(void);
/* USER CODE END 0 */

/**
  * @brief  The application entry point.
  * @retval int
  */
int main(void)
{
  /* USER CODE BEGIN 1 */

//  uint32_t		lux,noisy;
//  uint32_t		start = 0;
//  uint32_t		light_status = 0;
//  float temperature, humidity;

	uint32_t		last_time = 0; /*每隔3s上报一次,上一次上报的时间*/
	unsigned char	buf[256]; /*WiFi模块socket接收的buffer */
	int				rv;

	char			ipaddr[16];
	char			gateway[16];
	unsigned char	wifi_flag = 0;

  /* 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_TIM6_Init();
  MX_USART1_UART_Init();
  MX_ADC1_Init();
  MX_USART2_UART_Init();
  /* USER CODE BEGIN 2 */

  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */

  //sysled_hearbeat();
  //beep_start(3,300);
  printf("Start BearKE1 5G NB_IoT Board Example Program v1.0\r\n");
  printf("Welcome Mr.deng!\r\n");

  OLED_Init();
  OLED_ShowBanner(TIME_1S*2);

  esp8266_module_init();

  while(1)
  {
	  /*wiFi没有连接上无线路由器的话，开始连接无线路由器并ping测试*/
	  if(!(wifi_flag&FLAG_WIFI_CONNECTED))
	  {
		  if(esp8266_join_network("SSID", "password"))//填写自己的WiFi信息
		  {
			  esp8266_module_init();
			  HAL_Delay(2000);
			  continue;
		  }
		  if(esp8266_get_ipaddr(ipaddr, gateway, sizeof(ipaddr)))
		  {
			  HAL_Delay(1000);
			  continue;
		  }
		  if(esp8266_ping_test(gateway))
		  {
			  HAL_Delay(1000);
			  continue;
		  }
		  wifi_flag |= FLAG_WIFI_CONNECTED; /* set wifi connected flag */
	  }

	  /*网络socket没有连接上Socket服务器的话就开始连接Socket服务器 */
	  if(!(wifi_flag&FLAG_SOCK_CONNECTED))
	  {
		  if(esp8266_sock_connect("192.168.0.120", 12345))//修改为自己对应的IP与端口
		  {
			  HAL_Delay(1000);
			  continue;
		  }
		  wifi_flag |= FLAG_SOCK_CONNECTED; /* set wifi connected flag */
	  }
	  /*接收并且打印Socket服务器发送过来的数据*/
//	  rv = esp8266_sock_recv(buf, sizeof(buf));
//	  printf(("%d\n"), rv);
	  if( (rv=esp8266_sock_recv(buf, sizeof(buf))) > 0 )
	  {
		  parser_led_json((char *)buf, rv);
		  printf("ESP8266 socket receive %d bytes data: %s\n", rv, buf);
	  }


	  /*定时发数据到Socket服务器*/
	  if(time_after(HAL_GetTick(), last_time+3000))
	  {
		  rv = report_tempRH_json();
		  if( rv == 0 )
		  {
			  printf("ESP8266 socket send message ok\n");
		  }
		  else
		  {
			  printf("ESP8266 socket send message failure, rv=%d\n", rv);
			  wifi_flag &= ~FLAG_SOCK_CONNECTED;/* clear socket connected flag */

			  if(esp8266_ping_test(gateway))
			  {
				  wifi_flag &= ~FLAG_WIFI_CONNECTED;/* clear wifi connected flag */
			  }
		  }

		  last_time = HAL_GetTick();/*update last report time */
	  }
//	  uart_forward();//后面使用无线通讯时只需要用Socket通信，不在需要此转发程序，如果没有注释掉会报错，并不会执行PC发的JOSN指令
#if 0
	  /*sht30*/
	  report_tempRH_json();
	  HAL_Delay(3000);

	  /*json上报*/
	  proc_uart1_recv();
	  if( report_tempRH_json() < 0 )
	  {
		  printf("ERROR: UART report temperature and relative humidity failure\r\n");
	  }
	  HAL_Delay(3000);

//	  if( DHT11_SampleData(&temperature, &humidity) < 0 )
//	  {
//		  printf("ERROR: DHT11 Sample Data failure\r\n");
//	  }
//	  else
//	  {
//		  printf("DHT11 Sample Temperature: %.3f Relative Humidity: %.3f\r\n", temperature, humidity);
//	  }
//
//
//	  HAL_Delay(1000);

//Tag:灯光
//	if( OFF == light_status )
//	{
//		adc_sample_lux_noisy(&lux, &noisy);
//		printf("Lux[%lu] Noisy[%lu]\r\n", lux, noisy);
//		if( lux<400 && noisy>800 )
//		{
//			printf("Turn Light on\r\n");
//			turn_relay(Relay2,ON);
//			turn_led(GreenLed,ON);//还得写turn_Led()
//			light_status = ON;
//
//			start = HAL_GetTick();
//		}
			HAL_Delay(5000);
//	}
//
//	else
//	{
//		if( time_after(HAL_GetTick(), start+15000) )
//		{
//			printf("Turn Light off\r\n");
//			turn_relay(Relay2,OFF);
//			turn_led(GreenLed,OFF);
//			turn_led(RedLed,ON);
//
//			HAL_Delay(1000);
//			turn_led(RedLed,OFF);
//
//			light_status = OFF;
//		}
//
//	}
//
//	HAL_Delay(10);
#endif
    /* 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};
  RCC_PeriphCLKInitTypeDef PeriphClkInit = {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.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLM = 1;
  RCC_OscInitStruct.PLL.PLLN = 20;
  RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV7;
  RCC_OscInitStruct.PLL.PLLQ = RCC_PLLQ_DIV2;
  RCC_OscInitStruct.PLL.PLLR = RCC_PLLR_DIV2;
  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_DIV1;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_4) != HAL_OK)
  {
    Error_Handler();
  }
  PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USART1|RCC_PERIPHCLK_USART2
                              |RCC_PERIPHCLK_ADC;
  PeriphClkInit.Usart1ClockSelection = RCC_USART1CLKSOURCE_PCLK2;
  PeriphClkInit.Usart2ClockSelection = RCC_USART2CLKSOURCE_PCLK1;
  PeriphClkInit.AdcClockSelection = RCC_ADCCLKSOURCE_PLLSAI1;
  PeriphClkInit.PLLSAI1.PLLSAI1Source = RCC_PLLSOURCE_HSE;
  PeriphClkInit.PLLSAI1.PLLSAI1M = 1;
  PeriphClkInit.PLLSAI1.PLLSAI1N = 9;
  PeriphClkInit.PLLSAI1.PLLSAI1P = RCC_PLLP_DIV7;
  PeriphClkInit.PLLSAI1.PLLSAI1Q = RCC_PLLQ_DIV2;
  PeriphClkInit.PLLSAI1.PLLSAI1R = RCC_PLLR_DIV6;
  PeriphClkInit.PLLSAI1.PLLSAI1ClockOut = RCC_PLLSAI1_ADC1CLK;
  if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK)
  {
    Error_Handler();
  }
  /** Configure the main internal regulator output voltage
  */
  if (HAL_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE1) != HAL_OK)
  {
    Error_Handler();
  }
}

/* USER CODE BEGIN 4 */
int parser_led_json(char *json_string, int bytes)
{
	JSONStatus_t result;
	char save;
	char *value;
	size_t valen;
	int i;

	printf("DBUG: Start parser JSON string: %s\r\n", json_string);
	result = JSON_Validate(json_string, bytes);
	/* JSON document is valid so far but incomplete */
	if( JSONPartial == result )
	{
		printf("WARN: JSON document is valid so far but incomplete!\r\n");
		return 0;
	}

	/* JSON document is not valid JSON */
	if( JSONSuccess != result )
	{
		printf("ERROR: JSON document is not valid JSON!\r\n");
		return -1;
	}
	/* Parser and set LED status */
	for(i=0; i<LedMax; i++)
	{
		result = JSON_Search( json_string, bytes, leds[i].name, strlen(leds[i].name), &value, &valen);
		if( JSONSuccess == result )
		{
			save = value[valen];
			value[valen] = '\0';

			if( !strncasecmp(value, "on", 2) )
			{
				printf("DBUG: turn %s on\r\n", leds[i].name);
				turn_led(i, ON);
			}
			else if( !strncasecmp(value, "off", 3) )
			{
				printf("DBUG: turn %s off\r\n", leds[i].name);
				turn_led(i, OFF);
			}

			value[valen] = save;
		}
	}
	return 1;
}

void proc_uart1_recv(void)
{
	if( g_uart1_bytes > 0 )
	{
		HAL_Delay(200);
		if( 0 != parser_led_json(g_uart1_rxbuf, g_uart1_bytes) )
		{
			clear_uart1_rxbuf();
		}
	}
}

/*json上报*/
//int report_tempRH_json(void)
//{
//	char buf[128];
//	float temperature, humidity;
//
//
//	if ( DHT11_SampleData(&temperature, &humidity) < 0 )
//	{
//		printf("ERROR: DHT11 Sample data failure\n");
//		return -1;
//	}
//
//
//	memset(buf, 0, sizeof(buf));
//	snprintf(buf, sizeof(buf), "{\"Temperature\":\"%.2f\", \"Humidity\":\"%.2f\"}", temperature, humidity);
//
//	HAL_UART_Transmit(&huart1 , (uint8_t *)buf, strlen(buf), 0xFFFF);
//
//	return 0;
//}

/*sht30采样*/
int report_tempRH_json(void)
{
	char buf[128];
	float temperature, humidity;
	uint32_t temp, humd;
	int	rv;

	if ( SHT30_SampleData(&temperature, &humidity) < 0 )
	{
		printf("ERROR: SHT30 Sample data failure\n");
		return -1;
	}


	memset(buf, 0, sizeof(buf));
	snprintf(buf, sizeof(buf), "{\"Temperature\":\"%.2f\", \"Humidity\":\"%.2f\"}", temperature, humidity);

	temp = (int)(temperature*100);
	humd = (int)(humidity*100);
	OLED_ShowTempHumdity(temp, humd, TIME_1S*2);

	rv = esp8266_sock_send((uint8_t *)buf, strlen(buf));
//	HAL_UART_Transmit(&huart1 , (uint8_t *)buf, strlen(buf), 0xFFFF);

	return rv>0 ? 0 : -2;
}
/* 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 */

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/

注意：需要注释掉转发程序，不然无法控制Led灯

3.运行测试

总结

首先，对于STM32单片机在写博客之前学习了，所以没有，之后可能也会对之前的内容整理为博客，包括Led、DHT11、SHT30、I2C协议、SPI协议及JSON格式远程控制等，所以之前内容并未包括在此篇当中。

本篇为ESP8266 WiFi模块实时上报温湿度及控制LED灯项目笔记，主要介绍和应用了ESP8266 WiFi模块，编写了串口转发程序，学习了AT命令等，最终实现了ESP8266 WiFi模块实时上报温湿度及控制LED灯项目。

别忘了点赞 关注 收藏呀！