ESP8266获取网络时间 实时时钟

程序现象

 

一、用串口调试助手调试

1.发送指令AT+RST重启模块使应用模式更改生效；

2.发送指令ATE0取消回显

3.使用串口发送指令AT+CWMODE=1设置模块Wi-Fi应用模式为Station模式；

4.发送指令AT+CWJAP ="ssid","pwd"连接AP；

5.发送指令AT+CIPMUX=0设置模块为单路连接模式，模块默认为单路连接模式；

6.发送指令AT+CIPSTART="TCP","api.k780.com",80 与服务器建立TCP连接 ;

7.发送指令AT+CIPMODE=1设置模块传输模式为透传模式；

8.发送指令AT+CIPSEND开启透传模式向服务器发送数据，模块收到此指令后先换行后返回“>”

9.剩下只需要发送 GET http://api.k780.com:88/?app=life.time&appkey=10003&sign=b59bc3ef6191eb9f747dd4e83c99f2a4&format=json&HTTP/1.1\r\n，就能获取到年月时间。      （调用一个网络API接口，这个接口会返回标准网络时间）

 可以看到发送完第九条指令后会收到如上图，所以整体思路：用串口进行通信，发送AT指令，获取到的数据存在Buf中，然后对Buf中的数据解析。获取timestamp后为时间戳，获取datetime_1后为日期时间。

USART串口模块

这一部分的初始化和之前一样，串口接收部分要进行判断如果接收到 '>' ，用Flag标记表示后面调用API后会收到时间戳和时间等数据。

#include "stm32f10x.h"                  // Device header
#include "MyUSART.h"
#include "esp.h"
#include 

char Buf[512];
unsigned char i;
uint8_t Flag;


void MyUSART_Init(void)
{
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1 ,ENABLE);
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA ,ENABLE);
	
	GPIO_InitTypeDef GPIO_InitStructure;                
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_Init(GPIOA,&GPIO_InitStructure);
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_Init(GPIOA,&GPIO_InitStructure);
	
	USART_InitTypeDef USART_InitStructure;              
	USART_InitStructure.USART_BaudRate = 115200;
	USART_InitStructure.USART_HardwareFlowControl =USART_HardwareFlowControl_None;
	USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
	USART_InitStructure.USART_Parity =USART_Parity_No ;
	USART_InitStructure.USART_StopBits = USART_StopBits_1;
	USART_InitStructure.USART_WordLength = USART_WordLength_8b;
	USART_Init (USART1,&USART_InitStructure);
	
	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
	NVIC_InitTypeDef NVIC_InitStructure;
	NVIC_InitStructure.NVIC_IRQChannel =USART1_IRQn;
	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
	NVIC_Init(&NVIC_InitStructure);
	
	USART_ITConfig(USART1,USART_IT_RXNE,ENABLE);
	USART_Cmd(USART1,ENABLE);
	
}
void MyUSART_SendString(char* str)
{
	uint8_t stri=0;
	while(str[stri] != '\0')
		USART_SendData (USART1,str[stri++]);
}
void USART1_IRQHandler()
{
	if(USART_GetITStatus(USART1,USART_IT_RXNE))
	{
		Buf[i++]=USART_ReceiveData(USART1);
		if(Buf[i-1] == '>')
		{
			Flag=1;
		}
		else if((Buf[i-2]=='\r')&&(Buf[i-1]=='\n'))  
		{
			Buf[i-2]='\0';
			i = 0;
		}
		USART_ClearITPendingBit(USART1,USART_IT_RXNE);
	}
}

ESP8266WIFI模块

这一部分初始化操作发送AT指令，在主函数中根据返回的数字可以判断哪里有问题

Comman_Rec（）这个函数用来处理Buf中接收到的数据。

#include "stm32f10x.h"                  // Device header
#include "MyUSART.h"
#include 
#include 
#include "Delay.h"
#include "OLED.H"
#include 

extern char Buf[512];
const char* WIFI ="GT";
const char* PASS="123456789";
extern uint8_t Flag;
uint32_t timestamp_cnt;
char subdatetime_1[11]; 
char subdatetime_2[8];
uint32_t temp = 2;

int fputc(int ch,FILE *f )   //printf重定向  
{
	USART_SendData(USART1,(uint8_t)ch);
	while(USART_GetFlagStatus (USART1,USART_FLAG_TC) == RESET);
	return ch;
}
char esp_Init(void)
{

	memset(Buf,0,sizeof(Buf));
	printf("AT+RST\r\n");
	Delay_ms(2000);

	memset(Buf,0,sizeof(Buf));
	printf("ATE0\r\n");    //关闭回显memset(Buf,0,sizeof(Buf));
	Delay_ms(1000);
	if(strcmp(Buf,"OK")!=0 )
		return 1;
	
	memset(Buf,0,sizeof(Buf));
	printf("AT+CWMODE=1\r\n");
	Delay_ms(50);
	if(strcmp(Buf,"OK")!=0)
		return 2;
	
	
	memset(Buf,0,sizeof(Buf));
	printf("AT+CWJAP=\"%s\",\"%s\"\r\n",WIFI,PASS); //连接热点
	Delay_ms(1000);
	if(strcmp(Buf,"OK")!=0)
		return 3;
	
	memset(Buf,0,sizeof(Buf));
	printf("AT+CIPMUX=0\r\n");
	Delay_ms(500);
	if(strcmp(Buf,"OK")!=0)
		return 4;
	
	memset(Buf,0,sizeof(Buf));
	printf("AT+CIPSTART=\"TCP\",\"api.k780.com\",80\r\n");
	Delay_ms(500);
	if(strcmp(Buf,"OK")!=0)
		return 5;
	
	memset(Buf,0,sizeof(Buf));
	printf("AT+CIPMODE=1\r\n");
	Delay_ms(500);
	if(strcmp(Buf,"OK")!=0)
		return 6;
		
	memset(Buf,0,sizeof(Buf));
	printf("AT+CIPSEND\r\n");
	Delay_ms(500);
	if(Flag != 1)
		return 7;
	return 0;
}

void ESP_Pub(void)        //当接收到'>'时
{
	if(Flag == 1)
	{
		printf("GET http://api.k780.com:88/?app=life.time&appkey=10003&sign=b59bc3ef6191eb9f747dd4e83c99f2a4&format=json&HTTP/1.1\r\n");
		Delay_ms(2000);
	}
}


void Comman_Rec(void)
{
	    char *timestamp_start = strstr(Buf,"timestamp"); // 定位到"timestamp"字段的起始位置
		if (timestamp_start != NULL) 
		{
			timestamp_start += (strlen("timestamp")+3); // 跳过"timestamp"
			char timestamp[11];
			strncpy(timestamp, timestamp_start, 10); // 复制10个字符到timestamp数组
			timestamp[10] = '\0'; 					// 添加字符串结束符
			timestamp_cnt =atoi(timestamp);		//转换为整数
		}
		char *datetime1_start = strstr(Buf,"datetime_1"); 
		if (datetime1_start != NULL) 
		{
			datetime1_start += (strlen("datetime_1")+3); 
			strncpy(subdatetime_1, datetime1_start, 10); 
			subdatetime_1[10] = '\0'; 
			strncpy(subdatetime_2, datetime1_start+11, 7); 
			subdatetime_2[7] = '\0'; 

		}
}

主函数

#include "stm32f10x.h"                  // Device header
#include "OLED.H"
#include 
#include "Delay.h"
#include "MyUSART.H" 
#include "esp.h"

extern char Buf[512];
extern uint8_t Flag;
extern uint32_t timestamp_cnt;
extern char subdatetime_1[11];
extern char subdatetime_2[9];


void Init(void)
{
	uint8_t Judge=0;
	OLED_Init();
	OLED_ShowString(1,1,"Linking..");
	Delay_ms(100);
	MyUSART_Init(); 
	
	do
	{
		Judge = esp_Init();
		OLED_ShowString(1,1,"code:    ");
		OLED_ShowNum(2,1,Judge,1);
	}while(Judge!=0);  

}

int main(void)
{
	Init();
	if(Flag==1)
	{
		OLED_ShowString(1,1,"SUCCESS");
	}
	else
	{
		OLED_ShowString(1,1,"FAIL");
	}
	while(1)
	{
		ESP_Pub();
		Comman_Rec();
		OLED_ShowNum(1,1,timestamp_cnt,10);
		OLED_ShowString(2,1,subdatetime_1);
		OLED_ShowString(3,1,subdatetime_2);

	}

}

注意：这个代码存在的问题是比标准的北京时间慢两秒，因为每次调用网络API接口都会Delay2秒，所以可以只获取时间戳，加上两秒后再根据网上的代码将时间戳转换为具体的时间格式。还可以根据上一节实时时钟的代码实现掉电不丢失的功能。而且有时候显示一会会跳变一下，也有很多问题，我在网上没找到stm32库函数的这个功能实现，还没找到更好的思路。