March 05, 2021 by gray makerfabs
A method that sets or changes ESP32 WiFi connection without re-programming.
This tutorial shows how to set the ESP32 WiFi connection secondly without re-programing.
In the past, I used to program ESP32 for setting or changing the WiFi. Once the WiFi setting needs to be changed, I will need to re-program the ESP32. When I show my ESP32 project to my audience, the ESP32 was not working because of the WiFi changed, and I must reset the ESP32 by re-programing, troublesome!~
So I want to set or change the ESP32 WiFi connection without re-programming that I have downloaded the program once.
After my research and testing, I found two problems in WiFi Setting without re-programming: how to transmit the WiFi name and password to ESP32; and how to store the information in ESP32.
ESP32 has to get the WiFi name and password for connecting to WiFi. In the past, the WiFi information can be in code and programmed to ESP32.
In the new method, the WiFi information can be transmitted from the phone to ESP32.
so the ESP32 can obtain the information from the server.
To Keep the WiFi info, the WiFi setting information needs to be store without being affected by the restart of the ESP32. Non-volatile storage (NVS) library is designed to store key-value pairs in flash. The information would be store in the NVS as the key. Now, ESP32 can be connected to the WiFi with the information read from the flash when it re-start.
void ap_init()
{
//WiFi.softAP(ssid, password);
WiFi.softAP("Makerfabs_ap");
IPAddress myIP = WiFi.softAPIP();
Serial.print("AP IP address: ");
Serial.println(myIP);
server.begin();
}int wifi_config_server()
{
WiFiClient client = server.available(); // listen for incoming clients
if (client) // if you get a client,
……set_wifi_from_url(get_request);void record_wifi(char *ssid, char *password)
{
esp_err_t err = nvs_flash_init();
if (err == ESP_ERR_NVS_NO_FREE_PAGES || err == ESP_ERR_NVS_NEW_VERSION_FOUND)
{
ESP_ERROR_CHECK(nvs_flash_erase());
err = nvs_flash_init();
}
ESP_ERROR_CHECK(err);
……check_wifi(ssid, password);
WiFi.begin(ssid, password);#include "wifi_save.h"
void setup()
{
Serial.begin(115200);
if(wifi_set_main())
{
Serial.println("Connect WIFI SUCCESS");
}
else
{
Serial.println("Connect WIFI FAULT");
}
}
void loop()
{
Serial.println("loop");
delay(3000);
}
You can view the result of the WiFi connection in the serial monitor window when the ESP32 board connected to the PC, also can check the result by the router.
Just after downloading the program, ESP32 can be connected or changed the WiFi without re-uploading the program, which is very convenient for people who have little or no Arduino and programming knowledge to set wifi connection secondly. It is suitable to use in the ESP32 project which will be shared with friends that need to connect to different WiFi.
Originally published at https://www.makerfabs.cc/article/how-to-connect-esp32-to-wifi-without-programming.html
