First knowledge of esp8266 (I) -- access point and wireless terminal mode

One . Model is introduced

1. Access point mode ： In access point mode ,ESP8266 Equivalent to a wireless router , Can send out wifi The signal , Other mobile computers can connect to this wifi The signal , But do not provide Internet service .

2. Wireless terminal mode ： In wireless terminal mode ,ESP8266 Like mobile phones and computers , Equivalent to a terminal , Be able to connect other wifi The signal , In the same wifi The terminal under the signal can communicate .

Two . Function introduction

1.WiFi.softAP(ssid,password)

Parameters ：ssid For the wifi Name of signal ,password Create for wifi The password of the signal

effect ： In access point mode, use this function to create wifi The signal

2.WiFi.softAPIP()

effect ： Print through this function in access point mode ESP8266 Of IP Address , here IP The address is fixed

3.WiFi.begin(ssid,password)

Parameters ：ssid Is the name of the access wireless ,password Password for wireless access

effect ： In wireless terminal mode , Access to ssid As the name ,password Wireless signal for password

4.WiFi.status()

effect ： In wireless terminal mode , return esp8266 Access wireless status , If the wireless connection is normal , Then the return WL_CONNECTED.

5.WiFi.localIP()

effect ： In wireless terminal mode , Back at this point ESP8266 Of IP Address , At this time IP The address is assigned by the wireless router

6.WiFi.SSID()

effect ： Under the wireless terminal , Return the access wireless name

7.wifiMulti.addAP("HUAWEI Mate 30","1234567890")

effect ： Add multiple wireless names and passwords ,ESP8266 Automatically select the connection with the strongest signal

8.wifiMulti.run()

effect ： And WiFi.status() similar , Return to the state of accessing the strongest wireless

3、 ... and . Code

// Access point mode 
#include <ESP8266WiFi.h>
void setup(void)
{
  const char *ssid="GCR";
  const char *password="12345678";
  Serial.begin(9600);
  // Create a GCR, The password for 12345678 Of wifi The signal 
  WiFi.softAP(ssid,password);
  Serial.print("Access Point:");
  Serial.println(ssid);
  Serial.print("Address:");
  // Print in access point mode IP Address 
  Serial.println(WiFi.softAPIP());
}
void loop(void)
{
  
}

// Wireless terminal mode 
#include <ESP8266WiFi.h>
void setup(void)
{
  int i=0;
  const char *ssid="HUAWEI Mate 30";
  const char *password="1234567890";
  Serial.begin(9600);
  // Access name is HUAWEI Mate 30, The password for 1234567890 Of wifi
  WiFi.begin(ssid,password);
  Serial.print("Connect to:");
  Serial.println(ssid);
  // Judge WiFi Whether to access , If there is no access, wait 
  while(WiFi.status()!=WL_CONNECTED)
  {
    delay(1000);
    Serial.print(i++);
    Serial.print("  ");
  }
  Serial.println(" ");
  Serial.println("Connect OK");
  // Print after connecting IP Address 
  Serial.println(WiFi.localIP());
}
void loop(void)
{
  
}

// Automatic connection is the strongest wifi
#include <ESP8266WiFi.h>
#include <ESP8266WiFiMulti.h>
// Create a class , You can call the functions of this class 
ESP8266WiFiMulti wifiMulti;
void setup(void)
{
  int i=0;
  Serial.begin(9600);
  // Add these two WiFi, Connect whichever signal is strong 
  wifiMulti.addAP("HUAWEI Mate 30","1234567890");
  wifiMulti.addAP("HUAWEI-B91AN8","ghs13934488149");
  Serial.println("Connecting...");
  // Judge the strongest signal wifi Whether to access , If there is no access, wait 
  while(wifiMulti.run()!=WL_CONNECTED)
  {
    delay(1000);
    Serial.print(i++);
    Serial.print("  ");
    }
    Serial.println("  ");
    // Access successful , Print access wifi Name and IP Address 
    Serial.println(WiFi.SSID());
    Serial.println(WiFi.localIP());
  }
void loop(void)
{
  
  }