AsyncESP32_Ethernet_Manager

Table of Contents

Why do we need this AsyncESP32_Ethernet_Manager library
- Features
- Why Async is better
- Currently supported Boards
Changelog
Prerequisites
Installation
- Use Arduino Library Manager
- Manual Install
- VS Code & PlatformIO
Libraries' Patches
- 1. For ESPAsyncWebServer library
Note for Platform IO using ESP32 LittleFS
HOWTO Fix Multiple Definitions Linker Error
HOWTO Use analogRead() with ESP32 running WiFi and/or BlueTooth (BT/BLE)
- 1. ESP32 has 2 ADCs, named ADC1 and ADC2
- 2. ESP32 ADCs functions
- 3. ESP32 WiFi uses ADC2 for WiFi functions
How It Works
HOWTO Basic configurations
- 1. Using default for every configurable parameter
- 2. Using many configurable parameters
- 3. Using STA-mode DHCP, but don't like to change to static IP or display in Config Portal
- 4. Using STA-mode DHCP, but permit to change to static IP and display in Config Portal
- 5. Using STA-mode StaticIP, and be able to change to DHCP IP and display in Config Portal
- 6. Using STA-mode StaticIP and configurable DNS, and be able to change to DHCP IP and display in Config Portal
- 7. Using STA-mode StaticIP and auto DNS, and be able to change to DHCP IP and display in Config Portal
- 8. Not using NTP to avoid issue with some WebBrowsers, especially in CellPhone or Tablets.
- 9. Using NTP feature with CloudFlare. System can hang until you have Internet access for CloudFlare.
- 10. Using NTP feature without CloudFlare to avoid system hang if no Internet access for CloudFlare.
- 11. Setting STA-mode static IP
- 12. Using CORS (Cross-Origin Resource Sharing) feature
- 13. How to auto getting _timezoneName
- 14. How to get TZ variable to configure Timezone
- 15. How to use the TZ variable to configure Timezone
HOWTO Open Config Portal
HOWTO Add Dynamic Parameters
- 1. Determine the variables to be configured via Config Portal (CP)
- 2. Initialize the variables to prepare for Config Portal (CP)
- 3. Add the variables to Config Portal (CP)
  - 3.1 addParameter() function Prototype:
  - 3.2 Code to add variables to CP
- 4. Save the variables configured in Config Portal (CP)
  - 4.1 Getting variables' data from CP
- 5. Write to FS (SPIFFS, LittleFS, etc.) using JSON format
- 6. Read from FS using JSON format
So, how it works?
Documentation
- Password protect the configuration Access Point
- Callbacks
  - Save settings
- ConfigPortal Timeout
- On Demand ConfigPortal
- Custom Parameters
- Custom IP Configuration
  - Custom Station (client) Static IP Configuration
- Custom HTML, CSS, Javascript
How to connect W5500 or ENC28J60 to ESP32
Examples
- Async_ConfigOnSwitch
- Async_ConfigOnSwitchFS
- Async_ConfigOnDoubleReset_TZ (now support ArduinoJson 6.0.0+ as well as 5.13.5-)
- Async_ConfigOnDoubleReset (now support ArduinoJson 6.0.0+ as well as 5.13.5-)
- Async_ConfigPortalParamsOnSwitch (now support ArduinoJson 6.0.0+ as well as 5.13.5-)
- Async_ESP32_FSWebServer
- Async_ESP32_FSWebServer_DRD
Example Async_ConfigOnSwitch
Debug Terminal Output Samples
- 1. Async_ConfigOnDoubleReset using LittleFS on ESP32_DEV with ESP32_ENC28J60
- 2. Async_ConfigOnSwichFS using LittleFS on ESP32_DEV with ESP32_W5500
- 3. Async_ESP32_FSWebServer_DRD using LittleFS on ESP32_DEV with ESP32_W5500
Debug
Troubleshooting
Issues
Contributions and Thanks
Contributing
License and credits
Copyright

Why do we need this Async AsyncESP32_Ethernet_Manager library

Features

This is an ESP32 + LwIP LwIP W5500 / ENC28J60 Credentials and Connection Manager with fallback Web ConfigPortal. This Library is used for configuring ESP32 Ethernet Static / DHCP and Credentials at runtime. You can specify static DNS servers, personalized HostName and CORS feature.

This library is based on, modified, bug-fixed and improved from:

Khoi Hoang's ESPAsync_WiFiManager

to use the better and faster asynchronous ESPAsyncWebServer.

Thanks to this AsyncESP32_Ethernet_Manager library is based on and sync'ed with ESPAsync_WiFiManager, all the features currently supported by ESPAsync_WiFiManager will be available. Please have a look at ESPAsync_WiFiManager for those too-many-to-list features.

Why Async is better

Using asynchronous network means that you can handle more than one connection at the same time
You are called once the request is ready and parsed
When you send the response, you are immediately ready to handle other connections while the server is taking care of sending the response in the background
Speed is OMG
Easy to use API, HTTP Basic and Digest MD5 Authentication (default), ChunkedResponse
Easily extensible to handle any type of content
Supports Continue 100
Async WebSocket plugin offering different locations without extra servers or ports
Async EventSource (Server-Sent Events) plugin to send events to the browser
URL Rewrite plugin for conditional and permanent url rewrites
ServeStatic plugin that supports cache, Last-Modified, default index and more
Simple template processing engine to handle templates

To appreciate the power of the ESPAsyncWebServer and underlying Async libraries, please compare the more efficient Async_ESP32_FSWebServer example example with the complicated twin ESP32_FSWebServer.

Currently supported Boards

This AsyncESP32_Ethernet_Manager library currently supports these following boards:

ESP32_DEV boards using LwIP W5500 / ENC28J60 Ethernet

W5500

ENC28J60

Prerequisites

Arduino IDE 1.8.19+ for Arduino.
ESP32 Core 2.0.5+ for ESP32-based boards.
ESPAsyncWebServer v1.2.3+. You have to use the latest forked ESPAsyncWebServer if the PR Fix compiler error for ESP32-C3 and mbed TLS v2.7.0+ #970 hasn't been merged. To install manually for Arduino IDE
ESPAsyncDNSServer v1.0.0+ or Forked ESPAsyncDNSServer v1.0.0+
AsyncTCP v1.1.1+. To install manually for Arduino IDE
ESP_DoubleResetDetector v1.3.2+ if using DRD feature. To install, check . Use v1.1.0+ if using LittleFS for ESP32 v1.0.6+.
WebServer_ESP32_W5500 library v1.5.1+ if necessary to use ESP32 boards using LwIP W5500 Ethernet. To install, check
WebServer_ESP32_ENC library v1.5.1+ if necessary to use ESP32 boards using LwIP ENC28J60 Ethernet. To install, check

Installation

Use Arduino Library Manager

The best and easiest way is to use Arduino Library Manager. Search for AsyncESP32_Ethernet_Manager, then select / install the latest version. You can also use this link for more detailed instructions.

Manual Install

Navigate to AsyncESP32_Ethernet_Manager page.
Download the latest release AsyncESP32_Ethernet_Manager-main.zip.
Extract the zip file to AsyncESP32_Ethernet_Manager-main directory
Copy the whole AsyncESP32_Ethernet_Manager-main folder to Arduino libraries' directory such as ~/Arduino/libraries/.

VS Code & PlatformIO:

Install VS Code
Install PlatformIO
Install AsyncESP32_Ethernet_Manager library by using Library Manager. Search for AsyncESP32_Ethernet_Manager in Platform.io Author's Libraries
Use included platformio.ini file from examples to ensure that all dependent libraries will installed automatically. Please visit documentation for the other options and examples at Project Configuration File

Libraries' Patches

1. For ESPAsyncWebServer library

If you don't use the forked ESPAsyncWebServer, to fix ESPAsyncWebServer library compile errors, just copy these following files into the ESPAsyncWebServer library directory to overwrite the old files:

Check the PR Fix compiler error for ESP32-C3 and mbed TLS v2.7.0+ #970

Note for Platform IO using ESP32 LittleFS

Necessary only for esp32 core v1.0.6-

From esp32 core v1.0.6+, LittleFS_esp32 v1.0.6 has been included and this step is not necessary anymore.

In Platform IO, to fix the error when using LittleFS_esp32 v1.0 for ESP32-based boards with ESP32 core v1.0.4- (ESP-IDF v3.2-), uncomment the following line

from

//#define CONFIG_LITTLEFS_FOR_IDF_3_2   /* For old IDF - like in release 1.0.4 */

to

#define CONFIG_LITTLEFS_FOR_IDF_3_2   /* For old IDF - like in release 1.0.4 */

It's advisable to use the latest LittleFS_esp32 v1.0.6+ to avoid the issue.

Thanks to Roshan to report the issue in Error esp_littlefs.c 'utime_p'

HOWTO Fix `Multiple Definitions` Linker Error

The current library implementation, using xyz-Impl.h instead of standard xyz.cpp, possibly creates certain Multiple Definitions Linker error in certain use cases.

You can use

#include <AsyncESP32_Ethernet_Manager.hpp>               //https://github.com/khoih-prog/AsyncESP32_Ethernet_Manager

in many files. But be sure to use the following #include <AsyncESP32_Ethernet_Manager.h> in just 1 .h, .cpp or .ino file, which must not be included in any other file, to avoid Multiple Definitions Linker Error

// To be included only in main(), .ino with setup() to avoid `Multiple Definitions` Linker Error
#include <AsyncESP32_Ethernet_Manager.h>          //https://github.com/khoih-prog/AsyncESP32_Ethernet_Manager

Check Async_ConfigOnDoubleReset_Multi for an example how and where to do so.

Have a look at the discussion in Different behaviour using the src_cpp or src_h lib #80

HOWTO Use analogRead() with ESP32 running WiFi and/or BlueTooth (BT/BLE)

Please have a look at ESP_WiFiManager Issue 39: Not able to read analog port when using the autoconnect example to have more detailed description and solution of the issue.

1. ESP32 has 2 ADCs, named ADC1 and ADC2

2. ESP32 ADCs functions

ADC1 controls ADC function for pins GPIO32-GPIO39
ADC2 controls ADC function for pins GPIO0, 2, 4, 12-15, 25-27

3.. ESP32 WiFi uses ADC2 for WiFi functions

Look in file adc_common.c

In ADC2, there're two locks used for different cases:

lock shared with app and Wi-Fi: ESP32: When Wi-Fi using the ADC2, we assume it will never stop, so app checks the lock and returns immediately if failed. ESP32S2: The controller's control over the ADC is determined by the arbiter. There is no need to control by lock.

lock shared between tasks: when several tasks sharing the ADC2, we want to guarantee all the requests will be handled. Since conversions are short (about 31us), app returns the lock very soon, we use a spinlock to stand there waiting to do conversions one by one.

adc2_spinlock should be acquired first, then adc2_wifi_lock or rtc_spinlock.

In order to use ADC2 for other functions, we have to acquire complicated firmware locks and very difficult to do
So, it's not advisable to use ADC2 with WiFi/BlueTooth (BT/BLE).
Use ADC1, and pins GPIO32-GPIO39
If somehow it's a must to use those pins serviced by ADC2 (GPIO0, 2, 4, 12, 13, 14, 15, 25, 26 and 27), use the fix mentioned at the end of ESP_WiFiManager Issue 39: Not able to read analog port when using the autoconnect example to work with ESP32 WiFi/BlueTooth (BT/BLE).

How It Works

The Async_ConfigOnSwitch example shows how it works and should be used as the basis for a sketch that uses this library.
The concept of Async_ConfigOnSwitch is that a new ESP32 will start a ConfigPortal when powered up and save the configuration data in non volatile memory. Thereafter, the ConfigPortal will only be started again if a button is pushed on the ESP32 module.
Using any network-enabled device with a browser (computer, phone, tablet) connect to the newly created Access Point (AP) (Dynamic or Static IP specified in sketch)

then connect WebBrowser to configurable ConfigPortal IP address, e.g. 192.168.232

HOWTO Basic configurations

1. Using default for every configurable parameter

Include in your sketch

#define USING_W5500           true
#define USING_ENC28J60        false

#include <esp_wifi.h>

// LittleFS has higher priority than SPIFFS
#if ( defined(ESP_ARDUINO_VERSION_MAJOR) && (ESP_ARDUINO_VERSION_MAJOR >= 2) )
  #define USE_LITTLEFS    true
  #define USE_SPIFFS      false
#elif defined(ARDUINO_ESP32C3_DEV)
  // For core v1.0.6-, ESP32-C3 only supporting SPIFFS and EEPROM. To use v2.0.0+ for LittleFS
  #define USE_LITTLEFS          false
  #define USE_SPIFFS            true
#endif

#if USE_LITTLEFS
  // Use LittleFS
  #include "FS.h"

  // Check cores/esp32/esp_arduino_version.h and cores/esp32/core_version.h
  //#if ( ESP_ARDUINO_VERSION >= ESP_ARDUINO_VERSION_VAL(2, 0, 0) )  //(ESP_ARDUINO_VERSION_MAJOR >= 2)
  #if ( defined(ESP_ARDUINO_VERSION_MAJOR) && (ESP_ARDUINO_VERSION_MAJOR >= 2) )
    #if (_ESPASYNC_ETH_MGR_LOGLEVEL_ > 3)
      #warning Using ESP32 Core 1.0.6 or 2.0.0+
    #endif

    // The library has been merged into esp32 core from release 1.0.6
    #include <LittleFS.h>       // https://github.com/espressif/arduino-esp32/tree/master/libraries/LittleFS

    FS* filesystem =      &LittleFS;
    #define FileFS        LittleFS
    #define FS_Name       "LittleFS"
  #else
    #if (_ESPASYNC_ETH_MGR_LOGLEVEL_ > 3)
      #warning Using ESP32 Core 1.0.5-. You must install LITTLEFS library
    #endif

    // The library has been merged into esp32 core from release 1.0.6
    #include <LITTLEFS.h>       // https://github.com/lorol/LITTLEFS

    FS* filesystem =      &LITTLEFS;
    #define FileFS        LITTLEFS
    #define FS_Name       "LittleFS"
  #endif

#elif USE_SPIFFS
  #include <SPIFFS.h>
  FS* filesystem =      &SPIFFS;
  #define FileFS        SPIFFS
  #define FS_Name       "SPIFFS"
#else
  // +Use FFat
  #include <FFat.h>
  FS* filesystem =      &FFat;
  #define FileFS        FFat
  #define FS_Name       "FFat"
#endif
//////

#define LED_BUILTIN       2
#define LED_ON            HIGH
#define LED_OFF           LOW

////////////////////////////////////////////////////

// You only need to format the filesystem once
//#define FORMAT_FILESYSTEM       true
#define FORMAT_FILESYSTEM         false

////////////////////////////////////////////////////

#include <AsyncESP32_Ethernet_Manager.h>               //https://github.com/khoih-prog/AsyncESP32_Ethernet_Manager

#define HTTP_PORT     80

2. Using many configurable parameters

Include in your sketch

#define USING_W5500           true
#define USING_ENC28J60        false

#include <esp_wifi.h>

// LittleFS has higher priority than SPIFFS
#if ( defined(ESP_ARDUINO_VERSION_MAJOR) && (ESP_ARDUINO_VERSION_MAJOR >= 2) )
  #define USE_LITTLEFS    true
  #define USE_SPIFFS      false
#elif defined(ARDUINO_ESP32C3_DEV)
  // For core v1.0.6-, ESP32-C3 only supporting SPIFFS and EEPROM. To use v2.0.0+ for LittleFS
  #define USE_LITTLEFS          false
  #define USE_SPIFFS            true
#endif

#if USE_LITTLEFS
  // Use LittleFS
  #include "FS.h"

  // Check cores/esp32/esp_arduino_version.h and cores/esp32/core_version.h
  //#if ( ESP_ARDUINO_VERSION >= ESP_ARDUINO_VERSION_VAL(2, 0, 0) )  //(ESP_ARDUINO_VERSION_MAJOR >= 2)
  #if ( defined(ESP_ARDUINO_VERSION_MAJOR) && (ESP_ARDUINO_VERSION_MAJOR >= 2) )
    #if (_ESPASYNC_ETH_MGR_LOGLEVEL_ > 3)
      #warning Using ESP32 Core 1.0.6 or 2.0.0+
    #endif

    // The library has been merged into esp32 core from release 1.0.6
    #include <LittleFS.h>       // https://github.com/espressif/arduino-esp32/tree/master/libraries/LittleFS

    FS* filesystem =      &LittleFS;
    #define FileFS        LittleFS
    #define FS_Name       "LittleFS"
  #else
    #if (_ESPASYNC_ETH_MGR_LOGLEVEL_ > 3)
      #warning Using ESP32 Core 1.0.5-. You must install LITTLEFS library
    #endif

    // The library has been merged into esp32 core from release 1.0.6
    #include <LITTLEFS.h>       // https://github.com/lorol/LITTLEFS

    FS* filesystem =      &LITTLEFS;
    #define FileFS        LITTLEFS
    #define FS_Name       "LittleFS"
  #endif

#elif USE_SPIFFS
  #include <SPIFFS.h>
  FS* filesystem =      &SPIFFS;
  #define FileFS        SPIFFS
  #define FS_Name       "SPIFFS"
#else
  // +Use FFat
  #include <FFat.h>
  FS* filesystem =      &FFat;
  #define FileFS        FFat
  #define FS_Name       "FFat"
#endif
//////

#define LED_BUILTIN       2
#define LED_ON            HIGH
#define LED_OFF           LOW

// These defines must be put before #include <ESP_DoubleResetDetector.h>
// to select where to store DoubleResetDetector's variable.
// For ESP32, You must select one to be true (EEPROM or SPIFFS)
// For ESP8266, You must select one to be true (RTC, EEPROM, SPIFFS or LITTLEFS)
// Otherwise, library will use default EEPROM storage

// These defines must be put before #include <ESP_DoubleResetDetector.h>
// to select where to store DoubleResetDetector's variable.
// For ESP32, You must select one to be true (EEPROM or SPIFFS)
// Otherwise, library will use default EEPROM storage
#if USE_LITTLEFS
  #define ESP_DRD_USE_LITTLEFS    true
  #define ESP_DRD_USE_SPIFFS      false
  #define ESP_DRD_USE_EEPROM      false
#elif USE_SPIFFS
  #define ESP_DRD_USE_LITTLEFS    false
  #define ESP_DRD_USE_SPIFFS      true
  #define ESP_DRD_USE_EEPROM      false
#else
  #define ESP_DRD_USE_LITTLEFS    false
  #define ESP_DRD_USE_SPIFFS      false
  #define ESP_DRD_USE_EEPROM      true
#endif

#define DOUBLERESETDETECTOR_DEBUG       true  //false

#include <ESP_DoubleResetDetector.h>      //https://github.com/khoih-prog/ESP_DoubleResetDetector

// Number of seconds after reset during which a
// subsequent reset will be considered a double reset.
#define DRD_TIMEOUT 10

// RTC Memory Address for the DoubleResetDetector to use
#define DRD_ADDRESS 0

//DoubleResetDetector drd(DRD_TIMEOUT, DRD_ADDRESS);
DoubleResetDetector* drd;//////

// Onboard LED I/O pin on NodeMCU board
const int PIN_LED = 2; // D4 on NodeMCU and WeMos. GPIO2/ADC12 of ESP32. Controls the onboard LED.

// You only need to format the filesystem once
//#define FORMAT_FILESYSTEM       true
#define FORMAT_FILESYSTEM         false

// Assuming max 49 chars
#define TZNAME_MAX_LEN            50
#define TIMEZONE_MAX_LEN          50

typedef struct
{
  char TZ_Name[TZNAME_MAX_LEN];     // "America/Toronto"
  char TZ[TIMEZONE_MAX_LEN];        // "EST5EDT,M3.2.0,M11.1.0"
  uint16_t checksum;
} EthConfig;

EthConfig         Ethconfig;

#define  CONFIG_FILENAME              F("/eth_cred.dat")
//////

// Indicates whether ESP has credentials saved from previous session, or double reset detected
bool initialConfig = false;

// Use false if you don't like to display Available Pages in Information Page of Config Portal
// Comment out or use true to display Available Pages in Information Page of Config Portal
// Must be placed before #include <AsyncESP32_Ethernet_Manager.h>
#define USE_AVAILABLE_PAGES     true  //false

// To permit disable/enable StaticIP configuration in Config Portal from sketch. Valid only if DHCP is used.
// You'll loose the feature of dynamically changing from DHCP to static IP, or vice versa
// You have to explicitly specify false to disable the feature.
//#define USE_STATIC_IP_CONFIG_IN_CP          false

// Use false to disable NTP config. Advisable when using Cellphone, Tablet to access Config Portal.
// See Issue 23: On Android phone ConfigPortal is unresponsive (https://github.com/khoih-prog/ESP_WiFiManager/issues/23)
#define USE_ESP_ETH_MANAGER_NTP     true    //false

// Just use enough to save memory. On ESP8266, can cause blank ConfigPortal screen
// if using too much memory
#define USING_AFRICA        false
#define USING_AMERICA       true
#define USING_ANTARCTICA    false
#define USING_ASIA          false
#define USING_ATLANTIC      false
#define USING_AUSTRALIA     false
#define USING_EUROPE        false
#define USING_INDIAN        false
#define USING_PACIFIC       false
#define USING_ETC_GMT       false

// Use true to enable CloudFlare NTP service. System can hang if you don't have Internet access while accessing CloudFlare
// See Issue #21: CloudFlare link in the default portal (https://github.com/khoih-prog/ESP_WiFiManager/issues/21)
#define USE_CLOUDFLARE_NTP          false

#define USING_CORS_FEATURE          true

////////////////////////////////////////////

// Use USE_DHCP_IP == true for dynamic DHCP IP, false to use static IP which you have to change accordingly to your network
#if (defined(USE_STATIC_IP_CONFIG_IN_CP) && !USE_STATIC_IP_CONFIG_IN_CP)
  // Force DHCP to be true
  #if defined(USE_DHCP_IP)
    #undef USE_DHCP_IP
  #endif
  #define USE_DHCP_IP     true
#else
  // You can select DHCP or Static IP here
  //#define USE_DHCP_IP     true
  #define USE_DHCP_IP     false
#endif

#if ( USE_DHCP_IP )
  // Use DHCP

  #if (_ESPASYNC_ETH_MGR_LOGLEVEL_ > 3)
    #warning Using DHCP IP
  #endif

  IPAddress stationIP   = IPAddress(0, 0, 0, 0);
  IPAddress gatewayIP   = IPAddress(192, 168, 2, 1);
  IPAddress netMask     = IPAddress(255, 255, 255, 0);

#else
  // Use static IP

  #if (_ESPASYNC_ETH_MGR_LOGLEVEL_ > 3)
    #warning Using static IP
  #endif

  IPAddress stationIP   = IPAddress(192, 168, 2, 232);
  IPAddress gatewayIP   = IPAddress(192, 168, 2, 1);
  IPAddress netMask     = IPAddress(255, 255, 255, 0);
#endif

////////////////////////////////////////////


#define USE_CONFIGURABLE_DNS      true

IPAddress dns1IP      = gatewayIP;
IPAddress dns2IP      = IPAddress(8, 8, 8, 8);

#include <AsyncESP32_Ethernet_Manager.h>               //https://github.com/khoih-prog/AsyncESP32_Ethernet_Manager

#define HTTP_PORT     80

AsyncWebServer webServer(HTTP_PORT);
AsyncDNSServer dnsServer;

///////////////////////////////////////////
/******************************************
   // Defined in AsyncESP32_Ethernet_Manager.hpp
  typedef struct
  {
    IPAddress _sta_static_ip;
    IPAddress _sta_static_gw;
    IPAddress _sta_static_sn;
    #if USE_CONFIGURABLE_DNS
    IPAddress _sta_static_dns1;
    IPAddress _sta_static_dns2;
    #endif
  }  ETH_STA_IPConfig;
******************************************/

ETH_STA_IPConfig EthSTA_IPconfig;

3. Using STA-mode DHCP, but don't like to change to static IP or display in Config Portal

// You'll loose the feature of dynamically changing from DHCP to static IP, or vice versa
// You have to explicitly specify false to disable the feature.
#define USE_STATIC_IP_CONFIG_IN_CP          false

4. Using STA-mode DHCP, but permit to change to static IP and display in Config Portal

// You'll loose the feature of dynamically changing from DHCP to static IP, or vice versa
// You have to explicitly specify false to disable the feature.
//#define USE_STATIC_IP_CONFIG_IN_CP          false

// Use USE_DHCP_IP == true for dynamic DHCP IP, false to use static IP which you have to change accordingly to your network
#if (defined(USE_STATIC_IP_CONFIG_IN_CP) && !USE_STATIC_IP_CONFIG_IN_CP)
  // Force DHCP to be true
  #if defined(USE_DHCP_IP)
    #undef USE_DHCP_IP
  #endif
  #define USE_DHCP_IP     true
#else
  // You can select DHCP or Static IP here
  #define USE_DHCP_IP     true
#endif

5. Using STA-mode StaticIP, and be able to change to DHCP IP and display in Config Portal

// You'll loose the feature of dynamically changing from DHCP to static IP, or vice versa
// You have to explicitly specify false to disable the feature.
//#define USE_STATIC_IP_CONFIG_IN_CP          false

// Use USE_DHCP_IP == true for dynamic DHCP IP, false to use static IP which you have to change accordingly to your network
#if (defined(USE_STATIC_IP_CONFIG_IN_CP) && !USE_STATIC_IP_CONFIG_IN_CP)
// Force DHCP to be true
  #if defined(USE_DHCP_IP)
    #undef USE_DHCP_IP
  #endif
  #define USE_DHCP_IP     true
#else
  // You can select DHCP or Static IP here
  #define USE_DHCP_IP     false
#endif

6. Using STA-mode StaticIP and configurable DNS, and be able to change to DHCP IP and display in Config Portal

// You'll loose the feature of dynamically changing from DHCP to static IP, or vice versa
// You have to explicitly specify false to disable the feature.
//#define USE_STATIC_IP_CONFIG_IN_CP          false

// Use USE_DHCP_IP == true for dynamic DHCP IP, false to use static IP which you have to change accordingly to your network
#if (defined(USE_STATIC_IP_CONFIG_IN_CP) && !USE_STATIC_IP_CONFIG_IN_CP)
  // Force DHCP to be true
  #if defined(USE_DHCP_IP)
    #undef USE_DHCP_IP
  #endif
  #define USE_DHCP_IP     true
#else
  // You can select DHCP or Static IP here
  #define USE_DHCP_IP     false
#endif

#define USE_CONFIGURABLE_DNS      true

IPAddress dns1IP      = gatewayIP;
IPAddress dns2IP      = IPAddress(8, 8, 8, 8);

7. Using STA-mode StaticIP and auto DNS, and be able to change to DHCP IP and display in Config Portal

// You'll loose the feature of dynamically changing from DHCP to static IP, or vice versa
// You have to explicitly specify false to disable the feature.
//#define USE_STATIC_IP_CONFIG_IN_CP          false

// Use USE_DHCP_IP == true for dynamic DHCP IP, false to use static IP which you have to change accordingly to your network
#if (defined(USE_STATIC_IP_CONFIG_IN_CP) && !USE_STATIC_IP_CONFIG_IN_CP)
  // Force DHCP to be true
  #if defined(USE_DHCP_IP)
    #undef USE_DHCP_IP
  #endif
  #define USE_DHCP_IP     true
#else
  // You can select DHCP or Static IP here
  #define USE_DHCP_IP     false
#endif

#define USE_CONFIGURABLE_DNS      false

8. Not using NTP to avoid issue with some WebBrowsers, especially in CellPhone or Tablets.

// Use false to disable NTP config. Advisable when using Cellphone, Tablet to access Config Portal.
// See Issue 23: On Android phone ConfigPortal is unresponsive (https://github.com/khoih-prog/ESP_WiFiManager/issues/23)
#define USE_ESP_ETH_MANAGER_NTP     false

9. Using NTP feature with CloudFlare. System can hang until you have Internet access for CloudFlare.

// Use false to disable NTP config. Advisable when using Cellphone, Tablet to access Config Portal.
// See Issue 23: On Android phone ConfigPortal is unresponsive (https://github.com/khoih-prog/ESP_WiFiManager/issues/23)
#define USE_ESP_ETH_MANAGER_NTP     true

// Use true to enable CloudFlare NTP service. System can hang if you don't have Internet access while accessing CloudFlare
// See Issue #21: CloudFlare link in the default portal (https://github.com/khoih-prog/ESP_WiFiManager/issues/21)
#define USE_CLOUDFLARE_NTP          true

10. Using NTP feature without CloudFlare to avoid system hang if no Internet access for CloudFlare.

// Use false to disable NTP config. Advisable when using Cellphone, Tablet to access Config Portal.
// See Issue 23: On Android phone ConfigPortal is unresponsive (https://github.com/khoih-prog/ESP_WiFiManager/issues/23)
#define USE_ESP_ETH_MANAGER_NTP     true

// Use true to enable CloudFlare NTP service. System can hang if you don't have Internet access while accessing CloudFlare
// See Issue #21: CloudFlare link in the default portal (https://github.com/khoih-prog/ESP_WiFiManager/issues/21)
#define USE_CLOUDFLARE_NTP          false

11. Setting STA-mode static IP

//AsyncESP32_Ethernet_manager.setSTAStaticIPConfig(stationIP, gatewayIP, netMask, dns1IP, dns2IP);
AsyncESP32_Ethernet_manager.setSTAStaticIPConfig(WM_STA_IPconfig);

12. Using CORS (Cross-Origin Resource Sharing) feature

To use CORS feature with default CORS Header "". Some WebBrowsers won't accept this allowing-all "" CORS Header.

// Default false for using only whenever necessary to avoid security issue
#define USING_CORS_FEATURE     true

To use CORS feature with specific CORS Header "Your Access-Control-Allow-Origin". To be modified according to your specific Allowed-Origin.

// Default false for using only whenever necessary to avoid security issue
#define USING_CORS_FEATURE     true

...

#if USING_CORS_FEATURE
  ESP_wifimanager.setCORSHeader("Your Access-Control-Allow-Origin");
#endif

Not use CORS feature (default)

// Default false for using only whenever necessary to avoid security issue
#define USING_CORS_FEATURE     false

13. How to auto getting _timezoneName

Turn on auto NTP configuration by

// Use false to disable NTP config. Advisable when using Cellphone, Tablet to access Config Portal.
// See Issue 23: On Android phone ConfigPortal is unresponsive (https://github.com/khoih-prog/ESP_WiFiManager/issues/23)
#define USE_ESP_ETH_MANAGER_NTP     true

The _timezoneName, in the format similar to America/New_York, America/Toronto, Europe/London, etc., can be retrieved by using

String tempTZ = AsyncESP32_Ethernet_manager.getTimezoneName();

14. How to get TZ variable to configure Timezone

ESP32 TZ can be configured, using the similar to EST5EDT,M3.2.0,M11.1.0 (for America/New_York) , as follows:

// EST5EDT,M3.2.0,M11.1.0 (for America/New_York)
// EST5EDT is the name of the time zone
// EST is the abbreviation used when DST is off
// 6 hours is the time difference from GMT
// EDT is the abbreviation used when DST is on
// ,M3 is the third month
// .2 is the second occurrence of the day in the month
// .0 is Sunday
// ,M11 is the eleventh month
// .1 is the first occurrence of the day in the month
// .0 is Sunday

//configTzTime(WM_config.TZ, "pool.ntp.org" );
configTzTime(WM_config.TZ, "time.nist.gov", "0.pool.ntp.org", "1.pool.ntp.org");

To convert from _timezoneName to TZ, use the function getTZ() as follows:

const char * TZ_Result = AsyncESP32_Ethernet_manager.getTZ(_timezoneName);

The conversion depends on the stored TZs, which is using some memory, and can cause issue for ESP8266 in certain cases. Therefore, enable just the region you're interested.

For example, your application is used in America continent, you need just

#define USING_AMERICA       true

Hereafter is the regions' list

// Just use enough to save memory. On ESP8266, can cause blank ConfigPortal screen
// if using too much memory
#define USING_AFRICA        false
#define USING_AMERICA       true
#define USING_ANTARCTICA    false
#define USING_ASIA          false
#define USING_ATLANTIC      false
#define USING_AUSTRALIA     false
#define USING_EUROPE        false
#define USING_INDIAN        false
#define USING_PACIFIC       false
#define USING_ETC_GMT       false

15. How to use the TZ variable to configure Timezone

//configTzTime(WM_config.TZ, "pool.ntp.org" );
configTzTime(WM_config.TZ, "time.nist.gov", "0.pool.ntp.org", "1.pool.ntp.org");

then to print local time

void printLocalTime()
{
  struct tm timeinfo;

  getLocalTime( &timeinfo );
  Serial.print("Local Date/Time: ");
  Serial.print( asctime( &timeinfo ) );
}

HOWTO Open Config Portal

When you want to open a config portal, with default DHCP hostname ESP8266-XXXXXX or ESP32-XXXXXX, just add

#include <AsyncESP32_Ethernet_Manager.h>              //https://github.com/khoih-prog/AsyncESP32_Ethernet_Manager

#define HTTP_PORT           80

AsyncWebServer webServer(HTTP_PORT);
AsyncDNSServer dnsServer;

AsyncESP32_Ethernet_Manager AsyncESP32_Ethernet_manager(&webServer, &dnsServer);

If you'd like to have a personalized hostname (RFC952-conformed,- 24 chars max,- only a..z A..Z 0..9 '-' and no '-' as last char)

add

AsyncESP32_Ethernet_Manager AsyncESP32_Ethernet_manager(&webServer, &dnsServer, "Personalized-HostName");

then later call

AsyncESP32_Ethernet_manager.startConfigPortal()

While in Config Portal, connect to it using its AP IP, e.g. 192.168.2.232, configure Credentials, then save. The settings will be saved in non volatile memory. It will then reboot and autoconnect.

HOWTO Add Dynamic Parameters

These illustrating steps is based on the example Async_ConfigOnSwitchFS

1. Determine the variables to be configured via Config Portal (CP)

The application will:

use DHT sensor (either DHT11 or DHT22) and
need to connect to ThingSpeak with unique user's API Key.

The DHT sensor is connected to the ESP boards using SDA/SCL pins which also need to be configurable.

So this is the list of variables to be dynamically configured using CP

1. `thingspeakApiKey`,  type `char array`, max length 17 chars, and just arbitrarily selected default value to be "" or "ThingSpeak-APIKey"
2. `sensorDht22`,       type `bool`, default to be `true` (DHT22)
3. `pinSda`,            type `int`,  default to be `PIN_D2`
4. `pinScl`,            type `int`,  default to be `PIN_D1`

The Label can be any arbitrary string that help you identify the variable, but must be unique in your application

The initial code will be

#define API_KEY_LEN                 17

// Default configuration values
char thingspeakApiKey[API_KEY_LEN]  = "";
bool sensorDht22                    = true;
int pinSda                          = PIN_D2;     // Pin D2 mapped to pin GPIO4 of ESP8266
int pinScl                          = PIN_D1;     // Pin D1 mapped to pin GPIO5 of ESP8266

// Any unique string helping you identify the vars
#define ThingSpeakAPI_Label         "thingspeakApiKey"
#define SensorDht22_Label           "SensorDHT22"
#define PinSDA_Label                "PinSda"
#define PinSCL_Label                "PinScl"

2. Initialize the variables to prepare for Config Portal (CP)

The example Async_ConfigOnSwitchFS will open the CP whenever a SW press is detected in loop(). So the code to add dynamic variables will be there, just after the CP AsyncESP32_Ethernet_Manager class initialization to create AsyncESP32_Ethernet_Manager object.

void loop()
{
// is configuration portal requested?
  if ((digitalRead(TRIGGER_PIN) == LOW) || (digitalRead(TRIGGER_PIN2) == LOW))
  {
    Serial.println("\nConfiguration portal requested.");
    digitalWrite(LED_BUILTIN, LED_ON); // turn the LED on by making the voltage LOW to tell us we are in configuration mode.

    //Local initialization. Once its business is done, there is no need to keep it around
    AsyncESP32_Ethernet_Manager AsyncESP32_Ethernet_manager(&webServer, &dnsServer, "ConfigOnSwitchFS");

    //Check if there is stored WiFi router/password credentials.
    //If not found, device will remain in configuration mode until switched off via webserver.
    Serial.print("Opening configuration portal. ");
    
    ...
    
    // The addition of dynamic vars will be somewhere here
    
}

The ESPAsync_EMParameter class constructor will be used to initialize each newly-added parameter object.

2.1 Use the following simple constructor for simple variables such as `thingspeakApiKey`, `pinSda` and `pinScl` :

ESPAsync_EMParameter(const char *id, const char *placeholder, const char *defaultValue, int length);

2.2 For example, to create a new `ESPAsync_EMParameter` object `p_thingspeakApiKey` for `thingspeakApiKey`,

The command to use will be

ESPAsync_EMParameter p_thingspeakApiKey(ThingSpeakAPI_Label, "Thingspeak API Key", thingspeakApiKey, API_KEY_LEN);

where

- p_thingspeakApiKey                  : ESPAsync_EMParameter class object reference that stores the new Custom Parameter
- id => ThingSpeakAPI_Label           : var ref to Json associative name and HTML element ID for the new Custom Paramerter you just defined in step 1
- placeholder => "Thingspeak API Key" : HTML input placeholder and/or label element text the user sees in the configuration interface for this Custom Parameter
- defaultValue => thingspeakApiKey    : variable for storing the value of your Custom Parameter in the file system or default value when no data is entered
- length  => API_KEY_LEN              : max allowed length you want for this Custom Parameter to have

For pinSda and pinScl, the command will be similar

// I2C SCL and SDA parameters are integers so we need to convert them to char array but
// no other special considerations
char convertedValue[3];
sprintf(convertedValue, "%d", pinSda);
ESPAsync_EMParameter p_pinSda(PinSDA_Label, "I2C SDA pin", convertedValue, 3);

sprintf(convertedValue, "%d", pinScl);
ESPAsync_EMParameter p_pinScl(PinSCL_Label, "I2C SCL pin", convertedValue, 3);

where

- p_pinSda / p_pinScl                         : ESPAsync_EMParameter class object reference that stores the new Custom Parameter
- id => PinSDA_Label/PinSCL_Label             : var ref to Json associative name and HTML element ID for the new Custom Paramerter you just defined in step 1
- placeholder => "I2C SDA pin"/"I2C SCL pin"  : HTML input placeholder and/or label element text the user sees in the configuration interface for this Custom Parameter
- defaultValue => convertedValue              : variable for storing the value of your Custom Parameter in the file system or default value when no data is entered
- length  => 3                                : max allowed length you want for this Custom Parameter to have

2.3 Use the more complex following constructor for variables such as `sensorDht22`:

ESPAsync_EMParameter(const char *id, const char *placeholder, const char *defaultValue, int length, const char *custom, int labelPlacement);

2.4 For example, to create a new `ESPAsync_EMParameter` object `p_sensorDht22` for `sensorDht22`,

The command to use will be

ESPAsync_EMParameter p_sensorDht22(SensorDht22_Label, "DHT-22 Sensor", "T", 2, customhtml, WFM_LABEL_AFTER);

where

- p_sensorDht22                       : ESPAsync_EMParameter class object reference that stores the new Custom Parameter
- id => SensorDht22_Label             : var ref to Json associative name and HTML element ID for the new Custom Paramerter you just defined in step 1
- placeholder => "DHT-22 Sensor"      : HTML input placeholder and/or label element text the user sees in the configuration interface for this Custom Parameter
- defaultValue => "T"                 : variable for storing the value of your Custom Parameter in the file system or default value when no data is entered ("T" means `true`)
- length  => 2                        : max allowed length you want for this Custom Parameter to have
- custom => customhtml                : custom HTML code to add element type, e.g. `checkbox`, and `checked` when `sensorDht22 == true`
- labelPlacement => WFM_LABEL_AFTER   : to place label after

and customhtml Code is:

char customhtml[24] = "type=\"checkbox\"";

if (sensorDht22)
{
  strcat(customhtml, " checked");
}

3. Add the variables to Config Portal (CP)

Adding those ESPAsync_EMParameter objects created in Step 2 using the function addParameter() of object AsyncESP32_Ethernet_Manager

3.1 addParameter() function Prototype:

//adds a custom parameter
bool addParameter(ESPAsync_EMParameter *p);

3.2 Code to add variables to CP

Add parameter objects, previously created in Step 2, such as : p_thingspeakApiKey, p_sensorDht22, p_pinSda and p_pinScl

//add all parameters here

AsyncESP32_Ethernet_manager.addParameter(&p_thingspeakApiKey);
AsyncESP32_Ethernet_manager.addParameter(&p_sensorDht22);
AsyncESP32_Ethernet_manager.addParameter(&p_pinSda);
AsyncESP32_Ethernet_manager.addParameter(&p_pinScl);

4. Save the variables configured in Config Portal (CP)

When the CP exits, we have to store the parameters' values that users input via CP to use later.

For ESP32, that can be EEPROM or SPIFFS. While on ESP8266, LittleFS can be used besides EEPROM or deprecated SPIFFS.

We can write directly to a well-defined structure of our choice, but the current example is using JSON to be portable but much more complicated and not advised for new users.

4.1 Getting variables' data from CP

After users select Save, the CP AsyncESP32_Ethernet_Manager object will save the user input data into related ESPAsync_EMParameter objects.

We can now retrieve the data, using getValue() function, for each ESPAsync_EMParameter object. Then we can utilize the data for our purpose, such as thingspeakApiKey to log in, sensorDht22 type to know how to handle the sensor, pinSda and pinSda to know which pins to use to communicate with the DHT sensor.

The code is as follows:

// Getting posted form values and overriding local variables parameters
// Config file is written regardless the connection state
strcpy(thingspeakApiKey, p_thingspeakApiKey.getValue());
sensorDht22 = (strncmp(p_sensorDht22.getValue(), "T", 1) == 0);
pinSda = atoi(p_pinSda.getValue());
pinScl = atoi(p_pinScl.getValue());

We can also save to FS file to use later in next boot.

// Writing JSON config file to flash for next boot
writeConfigFile();

5. Write to FS (SPIFFS, LittleFS, etc.) using JSON format

First, you have to familiarize yourself with ArduinoJson library, its functions, the disruptive differences between ArduinoJson version 5.x.x- and v6.0.0+. The best documentation can be found at The best JSON library for embedded C++.

This documentation will discuss only ArduinoJson v6.x.x+ (ARDUINOJSON_VERSION_MAJOR >= 6)

Then have a look at the code snippet of writeConfigFile() function and the following step-by-step explanations.

bool writeConfigFile()
{
  Serial.println("Saving config file");

#if (ARDUINOJSON_VERSION_MAJOR >= 6)
  DynamicJsonDocument json(1024);
#else
  DynamicJsonBuffer jsonBuffer;
  JsonObject& json = jsonBuffer.createObject();
#endif

  // JSONify local configuration parameters
  json[ThingSpeakAPI_Label] = thingspeakApiKey;
  json[SensorDht22_Label] = sensorDht22;
  json[PinSDA_Label] = pinSda;
  json[PinSCL_Label] = pinScl;

  // Open file for writing
  File f = FileFS.open(CONFIG_FILE, "w");

  if (!f)
  {
    Serial.println("Failed to open config file for writing");
    return false;
  }

#if (ARDUINOJSON_VERSION_MAJOR >= 6)
  serializeJsonPretty(json, Serial);
  // Write data to file and close it
  serializeJson(json, f);
#else
  json.prettyPrintTo(Serial);
  // Write data to file and close it
  json.printTo(f);
#endif

  f.close();

  Serial.println("\nConfig file was successfully saved");
  return true;
}

5.1 Create a DynamicJsonDocument Object

We'll create an object with size 1024 bytes, enough to hold our data:

DynamicJsonDocument json(1024);

5.2 Fill the DynamicJsonDocument Object with data got from Config Portal

Then JSONify all local parameters we've just received from CP and wish to store into FS by using the function prototype:

json[Unique_Label] = Value_For_Unique_Label;

as follows:

// JSONify local configuration parameters
json[ThingSpeakAPI_Label] = thingspeakApiKey;
json[SensorDht22_Label]   = sensorDht22;
json[PinSDA_Label]        = pinSda;
json[PinSCL_Label]        = pinScl;

5.3 Open file to write the Jsonified data

This is the CONFIG_FILE file name we already declared at the beginning of the sketch (for ESP32):

#include <SPIFFS.h>
FS* filesystem =      &SPIFFS;
#define FileFS        SPIFFS
    
const char* CONFIG_FILE = "/ConfigSW.json";

Now just open the file for writing, and abort if open-for-writing error:

// Open file for writing
File f = FileFS.open(CONFIG_FILE, "w");

if (!f)
{
  Serial.println("Failed to open config file for writing");
  return false;
}

5.4 Write the Jsonified data to CONFIG_FILE

As simple as this single command to write the whole json object we declared then filled with data in steps 5.1 and 5.2

// Write data to file and close it
serializeJson(json, f);

5.5 Close CONFIG_FILE to flush and save the data

Soooo simple !!! Now everybody can do it.

f.close();

But HOWTO use the saved data in the next startup ???? That's in next step 6.

6. Read from FS using JSON format

Now, you have familiarized yourself with ArduinoJson library, its functions. We'll discuss HOWTO read data from the CONFIG_FILE in Jsonified format, then HOWTO parse the to use.

The documentation will discuss only ArduinoJson v6.x.x+ (ARDUINOJSON_VERSION_MAJOR >= 6)

First, have a look at the code snippet of readConfigFile() function.

bool readConfigFile()
{
  // this opens the config file in read-mode
  File f = FileFS.open(CONFIG_FILE, "r");

  if (!f)
  {
    Serial.println("Configuration file not found");
    return false;
  }
  else
  {
    // we could open the file
    size_t size = f.size();
    // Allocate a buffer to store contents of the file.
    std::unique_ptr<char[]> buf(new char[size + 1]);

    // Read and store file contents in buf
    f.readBytes(buf.get(), size);
    // Closing file
    f.close();
    // Using dynamic JSON buffer which is not the recommended memory model, but anyway
    // See https://github.com/bblanchon/ArduinoJson/wiki/Memory%20model

#if (ARDUINOJSON_VERSION_MAJOR >= 6)
    DynamicJsonDocument json(1024);
    auto deserializeError = deserializeJson(json, buf.get());
    if ( deserializeError )
    {
      Serial.println("JSON parseObject() failed");
      return false;
    }
    serializeJson(json, Serial);
#else
    DynamicJsonBuffer jsonBuffer;
    // Parse JSON string
    JsonObject& json = jsonBuffer.parseObject(buf.get());
    // Test if parsing succeeds.
    if (!json.success())
    {
      Serial.println("JSON parseObject() failed");
      return false;
    }
    json.printTo(Serial);
#endif

    // Parse all config file parameters, override
    // local config variables with parsed values
    if (json.containsKey(ThingSpeakAPI_Label))
    {
      strcpy(thingspeakApiKey, json[ThingSpeakAPI_Label]);
    }

    if (json.containsKey(SensorDht22_Label))
    {
      sensorDht22 = json[SensorDht22_Label];
    }

    if (json.containsKey(PinSDA_Label))
    {
      pinSda = json[PinSDA_Label];
    }

    if (json.containsKey(PinSCL_Label))
    {
      pinScl = json[PinSCL_Label];
    }
  }
  Serial.println("\nConfig file was successfully parsed");
  return true;
}

and the following step-by-step explanations.

6.1 Open CONFIG_FILE to read

As simple as this

// this opens the config file in read-mode
File f = FileFS.open(CONFIG_FILE, "r");

We'll inform and abort if the CONFIG_FILE can't be opened (file not found, can't be opened, etc.)

if (!f)
{
  Serial.println("Configuration file not found");
  return false;
}

6.2 Open CONFIG_FILE to read

Now we have to determine the file size to create a buffer large enough to store the to-be-read data

// we could open the file
size_t size = f.size();
// Allocate a buffer to store contents of the file.
std::unique_ptr<char[]> buf(new char[size + 1]);

Remember always add 1 to the buffer length to store the terminating 0.

Then just read the file into the buffer, and close the file to be safe

// Read and store file contents in buf
f.readBytes(buf.get(), size);
// Closing file
f.close();

6.3 Populate the just-read Jsonified data into the DynamicJsonDocument json object

We again use the same DynamicJsonDocument json object to store the data we've just read from CONFIG_FILE.

Why the same complicated DynamicJsonDocument json object ?? Because in steps 5, we did store Jsonified data using the same DynamicJsonDocument json object. It's much easier we now use it again to facilitate the parsing of Jsonified data back to the data we can use easily.

We first create the object with enough size

DynamicJsonDocument json(1024);

then populate it with data from buffer we read from CONFIG_FILE in step 6.2, pre-parse and check for error. All is done just by one command deserializeJson()

auto deserializeError = deserializeJson(json, buf.get());

Abort if there is any data error in the process of writing, storing, reading back. If OK, just nicely print out to the Debug Terminal

if ( deserializeError )
{
  Serial.println("JSON parseObject() failed");
  return false;
}

serializeJson(json, Serial);

6.4 Parse the Jsonified data from the DynamicJsonDocument json object to store into corresponding parameters

This is as simple as in the step 5.2, but in reverse direction.

To be sure there is good corresponding data, not garbage, for each variable, we have to perform sanity checks by verifying the DynamicJsonDocument json object still contains the correct keys we passed to it when we wrote into CONFIG_FILE.

For example:

if (json.containsKey(ThingSpeakAPI_Label))

Then proceed to get every parameter we know we stored there from last CP Save.

// Parse all config file parameters, override
// local config variables with parsed values
if (json.containsKey(ThingSpeakAPI_Label))
{
  strcpy(thingspeakApiKey, json[ThingSpeakAPI_Label]);
}

if (json.containsKey(SensorDht22_Label))
{
  sensorDht22 = json[SensorDht22_Label];
}

if (json.containsKey(PinSDA_Label))
{
  pinSda = json[PinSDA_Label];
}

if (json.containsKey(PinSCL_Label))
{
  pinScl = json[PinSCL_Label];
}

6.5 Then what to do now

Just use those parameters for whatever purpose you designed them for in step 1:

The application will use DHT sensor (either DHT11 or DHT22) and need to connect to ThingSpeak with unique user's API Key. The DHT sensor is connected to the ESP boards using SDA/SCL pins which also need to be configurable.

So, how it works?

In ConfigPortal Mode, it starts an access point @ the current Static or DHCP IP.

Connect to it by going to, e.g. http://192.168.2.232, you'll see this Main page:

Select Information to enter the Info page where the board info will be shown (long page)

Select Configuration to enter this page where you can modify its Credentials

Enter your credentials, then click Save. The Credentials will be saved and the board continues, or reboots if necessary, to connect to the selected Static IP or DHCP.

If you're already satisfied with the current settings and don't want to change anything, just select Exit Portal from the Main page to continue or reboot the board and connect using the previously-stored Credentials.

Documentation

Password protect the configuration Access Point

You can password protect the ConfigPortal AP. Check Async_ESP32_FSWebServer example

Callbacks

Save settings

This gets called when custom parameters have been set AND a connection has been established. Use it to set a flag, so when all the configuration finishes, you can save the extra parameters somewhere.

See Async_ConfigOnSwitchFS Example.

AsyncESP32_Ethernet_manager.setSaveConfigCallback(saveConfigCallback);

saveConfigCallback declaration and example

//flag for saving data
bool shouldSaveConfig = false;

//callback notifying us of the need to save config
void saveConfigCallback () 
{
  Serial.println("Should save config");
  shouldSaveConfig = true;
}

ConfigPortal Timeout

If you need to set a timeout so the ESP32 doesn't hang waiting to be configured for ever.

AsyncESP32_Ethernet_manager.setConfigPortalTimeout(120);

which will wait 2 minutes (120 seconds). When the time passes, the startConfigPortal() function will return and continue the sketch, unless you're accessing the Config Portal. In this case, the startConfigPortal() function will stay until you save config data or exit the Config Portal.

On Demand ConfigPortal

Example usage

void loop()
{
  // is configuration portal requested?
  if ((digitalRead(TRIGGER_PIN) == LOW) || (digitalRead(TRIGGER_PIN2) == LOW))
  {
    Serial.println(F("\nConfiguration portal requested."));
    digitalWrite(LED_BUILTIN, LED_ON); // turn the LED on by making the voltage LOW to tell us we are in configuration mode.

    //Local initialization. Once its business is done, there is no need to keep it around
    // Use this to default DHCP hostname to ESP32-XXXXXX
    //AsyncESP32_Ethernet_Manager AsyncESP32_Ethernet_manager(&webServer, &dnsServer);
    // Use this to personalize DHCP hostname (RFC952 conformed)
    AsyncWebServer webServer(HTTP_PORT);

#if ( USING_ESP32_S2 || USING_ESP32_C3 )
    AsyncESP32_Ethernet_Manager AsyncESP32_Ethernet_manager(&webServer, NULL, "ConfigOnSwitch");
#else
    AsyncDNSServer dnsServer;

    AsyncESP32_Ethernet_Manager AsyncESP32_Ethernet_manager(&webServer, &dnsServer, "ConfigOnSwitch");
#endif

#if !USE_DHCP_IP
#if USE_CONFIGURABLE_DNS
    // Set static IP, Gateway, Subnetmask, DNS1 and DNS2
    AsyncESP32_Ethernet_manager.setSTAStaticIPConfig(stationIP, gatewayIP, netMask, dns1IP, dns2IP);
#else
    // Set static IP, Gateway, Subnetmask, Use auto DNS1 and DNS2.
    AsyncESP32_Ethernet_manager.setSTAStaticIPConfig(stationIP, gatewayIP, netMask);
#endif
#endif

#if USING_CORS_FEATURE
    AsyncESP32_Ethernet_manager.setCORSHeader("Your Access-Control-Allow-Origin");
#endif

    //Check if there is stored credentials.
    //If not found, device will remain in configuration mode until switched off via webserver.
    Serial.println(F("Opening configuration portal. "));

    if (loadConfigData())
    {
      AsyncESP32_Ethernet_manager.setConfigPortalTimeout(
        120); //If no access point name has been previously entered disable timeout.
      Serial.println(F("Got stored Credentials. Timeout 120s for Config Portal"));
    }
    else
    {
      // Enter CP only if no stored SSID on flash and file
      AsyncESP32_Ethernet_manager.setConfigPortalTimeout(0);
      Serial.println(F("Open Config Portal without Timeout: No stored Credentials."));
      initialConfig = true;
    }

    //Starts an access point
    //and goes into a blocking loop awaiting configuration
    if (!AsyncESP32_Ethernet_manager.startConfigPortal())
      Serial.println(F("Not connected to ETH network but continuing anyway."));
    else
    {
      Serial.println(F("ETH network connected...yeey :)"));
      Serial.print(F("Local IP: "));
      Serial.println(ETH.localIP());
    }

#if USE_ESP_ETH_MANAGER_NTP
    String tempTZ = AsyncESP32_Ethernet_manager.getTimezoneName();

    if (strlen(tempTZ.c_str()) < sizeof(Ethconfig.TZ_Name) - 1)
      strcpy(Ethconfig.TZ_Name, tempTZ.c_str());
    else
      strncpy(Ethconfig.TZ_Name, tempTZ.c_str(), sizeof(Ethconfig.TZ_Name) - 1);

    const char * TZ_Result = AsyncESP32_Ethernet_manager.getTZ(Ethconfig.TZ_Name);

    if (strlen(TZ_Result) < sizeof(Ethconfig.TZ) - 1)
      strcpy(Ethconfig.TZ, TZ_Result);
    else
      strncpy(Ethconfig.TZ, TZ_Result, sizeof(Ethconfig.TZ_Name) - 1);

    if ( strlen(Ethconfig.TZ_Name) > 0 )
    {
      LOGERROR3(F("Saving current TZ_Name ="), Ethconfig.TZ_Name, F(", TZ = "), Ethconfig.TZ);

      //configTzTime(Ethconfig.TZ, "pool.ntp.org" );
      configTzTime(Ethconfig.TZ, "time.nist.gov", "0.pool.ntp.org", "1.pool.ntp.org");
    }
    else
    {
      LOGERROR(F("Current Timezone Name is not set. Enter Config Portal to set."));
    }

#endif

    AsyncESP32_Ethernet_manager.getSTAStaticIPConfig(EthSTA_IPconfig);

    saveConfigData();

#if !USE_DHCP_IP

    // Reset to use new Static IP, if different from current ETH.localIP()
    if (ETH.localIP() != EthSTA_IPconfig._sta_static_ip)
    {
      Serial.print(F("Current IP = "));
      Serial.print(ETH.localIP());
      Serial.print(F(". Reset to take new IP = "));
      Serial.println(EthSTA_IPconfig._sta_static_ip);

      ESP.restart();
      delay(2000);
    }

#endif

    digitalWrite(LED_BUILTIN, LED_OFF); // Turn led off as we are not in configuration mode.
  }

  // put your main code here, to run repeatedly
  check_status();
}

See Async_ConfigOnSwitch example for a more complex version.

Custom Parameters

Many applications need configuration parameters like MQTT host and port, Blynk or emoncms tokens, etc. While it is possible to use AsyncESP32_Ethernet_Manager to collect additional parameters, it is better to read these parameters from a web service once AsyncESP32_Ethernet_Manager has been used to connect to the Internet.

To capture other parameters with AsyncESP32_Ethernet_Manager is a little bit more complicated than all the other features. This requires adding custom HTML to your form.

If you want to do it with AsyncESP32_Ethernet_Manager see the example Async_ConfigOnSwitchFS

Custom IP Configuration

You can set a custom IP for both AP (access point, config mode) and STA (station mode, client mode, normal project state)

Custom Station (client) Static IP Configuration

This will use the specified IP configuration instead of using DHCP in station mode.

AsyncESP32_Ethernet_manager.setSTAStaticIPConfig(IPAddress(192,168,2,232), IPAddress(192,168,2,1), IPAddress(255,255,255,0));

Custom HTML, CSS, Javascript

There are various ways in which you can inject custom HTML, CSS or Javascript into the ConfigPortal.

The options are:

inject custom head element

You can use this to any html bit to the head of the ConfigPortal. If you add a <style> element, bare in mind it overwrites the included css, not replaces.

AsyncESP32_Ethernet_manager.setCustomHeadElement("<style>html{filter: invert(100%); -webkit-filter: invert(100%);}</style>");

inject a custom bit of html in the configuration form

ESPAsync_EMParameter custom_text("<p>This is just a text paragraph</p>");
AsyncESP32_Ethernet_manager.addParameter(&custom_text);

inject a custom bit of html in a configuration form element Just add the bit you want added as the last parameter to the custom parameter constructor.

ESPAsync_EMParameter custom_mqtt_server("server", "mqtt server", "iot.eclipse", 40, " readonly");

How to connect W5500 or ENC28J60 to ESP32

You can change the INT pin to another one. Default is GPIO4

// Must connect INT to GPIOxx or not working
#define INT_GPIO            4

W5500

ENC28J60

W5500 or ENC28J60	<--->	ESP32
MOSI	<--->	GPIO23
MISO	<--->	GPIO19
SCK	<--->	GPIO18
SS	<--->	GPIO5
INT	<--->	GPIO4
GND	<--->	GND
3.3V	<--->	3.3V

Examples

Async_ConfigOnSwitch
Async_ConfigOnSwitchFS
Async_ConfigOnDoubleReset_TZ (now support ArduinoJson 6.0.0+ as well as 5.13.5-)
Async_ConfigOnDoubleReset (now support ArduinoJson 6.0.0+ as well as 5.13.5-)
Async_ConfigPortalParamsOnSwitch (now support ArduinoJson 6.0.0+ as well as 5.13.5-)
Async_ESP32_FSWebServer
Async_ESP32_FSWebServer_DRD

Example Async_ConfigOnSwitch

AsyncESP32_Ethernet_Manager/examples/Async_ConfigOnSwitch/Async_ConfigOnSwitch.ino

Lines 26 to 1011 in 9d426c2

    
           #if !( defined(ESP32) ) 
        
             #error This code is intended to run on the (ESP32 + LwIP W5500 or ENC28J60) platform! Please check your Tools->Board setting. 
        
           #endif 
        
           #define USING_W5500           true 
        
           #define USING_ENC28J60        false 
        
           #if !USING_W5500 && !USING_ENC28J60 
        
             #undef USING_W5500 
        
             #define USING_W5500           true 
        
           #endif 
        
           ////////////////////////////////////////////////////////////// 
        
           // Use from 0 to 4. Higher number, more debugging messages and memory usage. 
        
           #define _ESPASYNC_ETH_MGR_LOGLEVEL_    4 
        
           // To not display stored SSIDs and PWDs on Config Portal, select false. Default is true 
        
           // Even the stored Credentials are not display, just leave them all blank to reconnect and reuse the stored Credentials 
        
           //#define DISPLAY_STORED_CREDENTIALS_IN_CP        false 
        
           ////////////////////////////////////////////////////////////// 
        
           // Enter a MAC address and IP address for your controller below. 
        
           #define NUMBER_OF_MAC      20 
        
           byte mac[][NUMBER_OF_MAC] = 
        
           { 
        
             { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0x01 }, 
        
             { 0xDE, 0xAD, 0xBE, 0xEF, 0xBE, 0x02 }, 
        
             { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0x03 }, 
        
             { 0xDE, 0xAD, 0xBE, 0xEF, 0xBE, 0x04 }, 
        
             { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0x05 }, 
        
             { 0xDE, 0xAD, 0xBE, 0xEF, 0xBE, 0x06 }, 
        
             { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0x07 }, 
        
             { 0xDE, 0xAD, 0xBE, 0xEF, 0xBE, 0x08 }, 
        
             { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0x09 }, 
        
             { 0xDE, 0xAD, 0xBE, 0xEF, 0xBE, 0x0A }, 
        
             { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0x0B }, 
        
             { 0xDE, 0xAD, 0xBE, 0xEF, 0xBE, 0x0C }, 
        
             { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0x0D }, 
        
             { 0xDE, 0xAD, 0xBE, 0xEF, 0xBE, 0x0E }, 
        
             { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0x0F }, 
        
             { 0xDE, 0xAD, 0xBE, 0xEF, 0xBE, 0x10 }, 
        
             { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0x11 }, 
        
             { 0xDE, 0xAD, 0xBE, 0xEF, 0xBE, 0x12 }, 
        
             { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0x13 }, 
        
             { 0xDE, 0xAD, 0xBE, 0xEF, 0xBE, 0x14 }, 
        
           }; 
        
           ////////////////////////////////////////////////////////// 
        
           #if USING_W5500 
        
           // For W5500 
        
           // Optional values to override default settings 
        
           // Don't change unless you know what you're doing 
        
           //#define ETH_SPI_HOST        SPI3_HOST 
        
           //#define SPI_CLOCK_MHZ       25 
        
           // Must connect INT to GPIOxx or not working 
        
           //#define INT_GPIO            4 
        
           //#define MISO_GPIO           19 
        
           //#define MOSI_GPIO           23 
        
           //#define SCK_GPIO            18 
        
           //#define CS_GPIO             5 
        
           ////////////////////////////////////////////////////////// 
        
           #else   // #if USING_W5500 
        
           ////////////////////////////////////////////////////////// 
        
           // For ENC28J60 
        
           // Optional values to override default settings 
        
           // Don't change unless you know what you're doing 
        
           // Optional values to override default settings 
        
           //#define SPI_HOST            1 
        
           //#define SPI_CLOCK_MHZ       8 
        
           // Must connect INT to GPIOxx or not working 
        
           //#define INT_GPIO            4 
        
           //#define MISO_GPIO           19 
        
           //#define MOSI_GPIO           23 
        
           //#define SCK_GPIO            18 
        
           //#define CS_GPIO             5 
        
           ////////////////////////////////////////////////////////// 
        
           #endif    // #if USING_W5500 
        
           ////////////////////////////////////////////////////////// 
        
           //For ESP32, To use ESP32 Dev Module, QIO, Flash 4MB/80MHz, Upload 921600 
        
           //Ported to ESP32 
        
           #include <esp_wifi.h> 
        
           ////////////////////////////////////////////////////////////// 
        
           // LittleFS has higher priority than SPIFFS 
        
           #if ( defined(ESP_ARDUINO_VERSION_MAJOR) && (ESP_ARDUINO_VERSION_MAJOR >= 2) ) 
        
             #define USE_LITTLEFS    true 
        
             #define USE_SPIFFS      false 
        
           #elif defined(ARDUINO_ESP32C3_DEV) 
        
             // For core v1.0.6-, ESP32-C3 only supporting SPIFFS and EEPROM. To use v2.0.0+ for LittleFS 
        
             #define USE_LITTLEFS          false 
        
             #define USE_SPIFFS            true 
        
           #endif 
        
           #if USE_LITTLEFS 
        
             // Use LittleFS 
        
             #include "FS.h" 
        
             // Check cores/esp32/esp_arduino_version.h and cores/esp32/core_version.h 
        
             //#if ( ESP_ARDUINO_VERSION >= ESP_ARDUINO_VERSION_VAL(2, 0, 0) )  //(ESP_ARDUINO_VERSION_MAJOR >= 2) 
        
             #if ( defined(ESP_ARDUINO_VERSION_MAJOR) && (ESP_ARDUINO_VERSION_MAJOR >= 2) ) 
        
               #if (_ESPASYNC_ETH_MGR_LOGLEVEL_ > 3) 
        
                 #warning Using ESP32 Core 1.0.6 or 2.0.0+ 
        
               #endif 
        
               // The library has been merged into esp32 core from release 1.0.6 
        
               #include <LittleFS.h>       // https://github.com/espressif/arduino-esp32/tree/master/libraries/LittleFS 
        
               FS* filesystem =      &LittleFS; 
        
               #define FileFS        LittleFS 
        
               #define FS_Name       "LittleFS" 
        
             #else 
        
               #if (_ESPASYNC_ETH_MGR_LOGLEVEL_ > 3) 
        
                 #warning Using ESP32 Core 1.0.5-. You must install LITTLEFS library 
        
               #endif 
        
               // The library has been merged into esp32 core from release 1.0.6 
        
               #include <LITTLEFS.h>       // https://github.com/lorol/LITTLEFS 
        
               FS* filesystem =      &LITTLEFS; 
        
               #define FileFS        LITTLEFS 
        
               #define FS_Name       "LittleFS" 
        
             #endif 
        
           #elif USE_SPIFFS 
        
             #include <SPIFFS.h> 
        
             FS* filesystem =      &SPIFFS; 
        
             #define FileFS        SPIFFS 
        
             #define FS_Name       "SPIFFS" 
        
           #else 
        
             // Use FFat 
        
             #include <FFat.h> 
        
             FS* filesystem =      &FFat; 
        
             #define FileFS        FFat 
        
             #define FS_Name       "FFat" 
        
           #endif 
        
           ////////////////////////////////////////////////////////////// 
        
           #define LED_BUILTIN       2 
        
           #define LED_ON            HIGH 
        
           #define LED_OFF           LOW 
        
           //See file .../hardware/espressif/esp32/variants/(esp32|doitESP32devkitV1)/pins_arduino.h 
        
           #define LED_BUILTIN       2         // Pin D2 mapped to pin GPIO2/ADC12 of ESP32, control on-board LED 
        
           #define LED_BUILTIN           2         // Pin D2 mapped to pin GPIO2/ADC12 of ESP32, control on-board LED 
        
           #define PIN_D0            0         // Pin D0 mapped to pin GPIO0/BOOT/ADC11/TOUCH1 of ESP32 
        
           #define PIN_D1            1         // Pin D1 mapped to pin GPIO1/TX0 of ESP32 
        
           #define PIN_D2            2         // Pin D2 mapped to pin GPIO2/ADC12/TOUCH2 of ESP32 
        
           #define PIN_D3            3         // Pin D3 mapped to pin GPIO3/RX0 of ESP32 
        
           #define PIN_D4            4         // Pin D4 mapped to pin GPIO4/ADC10/TOUCH0 of ESP32 
        
           #define PIN_D5            5         // Pin D5 mapped to pin GPIO5/SPISS/VSPI_SS of ESP32 
        
           #define PIN_D6            6         // Pin D6 mapped to pin GPIO6/FLASH_SCK of ESP32 
        
           #define PIN_D7            7         // Pin D7 mapped to pin GPIO7/FLASH_D0 of ESP32 
        
           #define PIN_D8            8         // Pin D8 mapped to pin GPIO8/FLASH_D1 of ESP32 
        
           #define PIN_D9            9         // Pin D9 mapped to pin GPIO9/FLASH_D2 of ESP32 
        
           #define PIN_D10           10        // Pin D10 mapped to pin GPIO10/FLASH_D3 of ESP32 
        
           #define PIN_D11           11        // Pin D11 mapped to pin GPIO11/FLASH_CMD of ESP32 
        
           #define PIN_D12           12        // Pin D12 mapped to pin GPIO12/HSPI_MISO/ADC15/TOUCH5/TDI of ESP32 
        
           #define PIN_D13           13        // Pin D13 mapped to pin GPIO13/HSPI_MOSI/ADC14/TOUCH4/TCK of ESP32 
        
           #define PIN_D14           14        // Pin D14 mapped to pin GPIO14/HSPI_SCK/ADC16/TOUCH6/TMS of ESP32 
        
           #define PIN_D15           15        // Pin D15 mapped to pin GPIO15/HSPI_SS/ADC13/TOUCH3/TDO of ESP32 
        
           #define PIN_D16           16        // Pin D16 mapped to pin GPIO16/TX2 of ESP32 
        
           #define PIN_D17           17        // Pin D17 mapped to pin GPIO17/RX2 of ESP32      
        
           #define PIN_D18           18        // Pin D18 mapped to pin GPIO18/VSPI_SCK of ESP32 
        
           #define PIN_D19           19        // Pin D19 mapped to pin GPIO19/VSPI_MISO of ESP32 
        
           #define PIN_D21           21        // Pin D21 mapped to pin GPIO21/SDA of ESP32 
        
           #define PIN_D22           22        // Pin D22 mapped to pin GPIO22/SCL of ESP32 
        
           #define PIN_D23           23        // Pin D23 mapped to pin GPIO23/VSPI_MOSI of ESP32 
        
           #define PIN_D24           24        // Pin D24 mapped to pin GPIO24 of ESP32 
        
           #define PIN_D25           25        // Pin D25 mapped to pin GPIO25/ADC18/DAC1 of ESP32 
        
           #define PIN_D26           26        // Pin D26 mapped to pin GPIO26/ADC19/DAC2 of ESP32 
        
           #define PIN_D27           27        // Pin D27 mapped to pin GPIO27/ADC17/TOUCH7 of ESP32      
        
           #define PIN_D32           32        // Pin D32 mapped to pin GPIO32/ADC4/TOUCH9 of ESP32 
        
           #define PIN_D33           33        // Pin D33 mapped to pin GPIO33/ADC5/TOUCH8 of ESP32 
        
           #define PIN_D34           34        // Pin D34 mapped to pin GPIO34/ADC6 of ESP32 
        
           //Only GPIO pin < 34 can be used as output. Pins >= 34 can be only inputs 
        
           //See .../cores/esp32/esp32-hal-gpio.h/c 
        
           //#define digitalPinIsValid(pin)          ((pin) < 40 && esp32_gpioMux[(pin)].reg) 
        
           //#define digitalPinCanOutput(pin)        ((pin) < 34 && esp32_gpioMux[(pin)].reg) 
        
           //#define digitalPinToRtcPin(pin)         (((pin) < 40)?esp32_gpioMux[(pin)].rtc:-1) 
        
           //#define digitalPinToAnalogChannel(pin)  (((pin) < 40)?esp32_gpioMux[(pin)].adc:-1) 
        
           //#define digitalPinToTouchChannel(pin)   (((pin) < 40)?esp32_gpioMux[(pin)].touch:-1) 
        
           //#define digitalPinToDacChannel(pin)     (((pin) == 25)?0:((pin) == 26)?1:-1) 
        
           #define PIN_D35           35        // Pin D35 mapped to pin GPIO35/ADC7 of ESP32 
        
           #define PIN_D36           36        // Pin D36 mapped to pin GPIO36/ADC0/SVP of ESP32 
        
           #define PIN_D39           39        // Pin D39 mapped to pin GPIO39/ADC3/SVN of ESP32 
        
           #define PIN_RX0            3        // Pin RX0 mapped to pin GPIO3/RX0 of ESP32 
        
           #define PIN_TX0            1        // Pin TX0 mapped to pin GPIO1/TX0 of ESP32 
        
           #define PIN_SCL           22        // Pin SCL mapped to pin GPIO22/SCL of ESP32 
        
           #define PIN_SDA           21        // Pin SDA mapped to pin GPIO21/SDA of ESP32    
        
           ////////////////////////////////////////////////////////////// 
        
           /* Trigger for inititating config mode is Pin D3 and also flash button on NodeMCU 
        
              Flash button is convenient to use but if it is pressed it will stuff up the serial port device driver 
        
              until the computer is rebooted on windows machines. 
        
           */ 
        
           #if ( USING_ESP32_S2 || USING_ESP32_C3 ) 
        
             const int TRIGGER_PIN = PIN_D3;   // Pin D3 mapped to pin GPIO03/ADC1-2/TOUCH3 of ESP32-S2 
        
             /* 
        
             Alternative trigger pin. Needs to be connected to a button to use this pin. It must be a momentary connection 
        
             not connected permanently to ground. Either trigger pin will work. 
        
             */ 
        
             const int TRIGGER_PIN2 = PIN_D4; // Pin D4 mapped to pin GPIO04/ADC1_3/TOUCH4 of ESP32-S2 
        
           #else 
        
             const int TRIGGER_PIN = PIN_D0;   // Pin D0 mapped to pin GPIO0/BOOT/ADC11/TOUCH1 of ESP32 
        
             /* 
        
             Alternative trigger pin. Needs to be connected to a button to use this pin. It must be a momentary connection 
        
             not connected permanently to ground. Either trigger pin will work. 
        
             */ 
        
             const int TRIGGER_PIN2 = PIN_D25; // Pin D25 mapped to pin GPIO25/ADC18/DAC1 of ESP32 
        
           #endif 
        
           ////////////////////////////////////////////////////////////// 
        
           // You only need to format the filesystem once 
        
           //#define FORMAT_FILESYSTEM       true 
        
           #define FORMAT_FILESYSTEM         false 
        
           ////////////////////////////////////////////////////////////// 
        
           // Assuming max 49 chars 
        
           #define TZNAME_MAX_LEN            50 
        
           #define TIMEZONE_MAX_LEN          50 
        
           typedef struct 
        
           { 
        
             char TZ_Name[TZNAME_MAX_LEN];     // "America/Toronto" 
        
             char TZ[TIMEZONE_MAX_LEN];        // "EST5EDT,M3.2.0,M11.1.0" 
        
             uint16_t checksum; 
        
           } EthConfig; 
        
           EthConfig         Ethconfig; 
        
           ////////////////////////////////////////////////////////////// 
        
           #define  CONFIG_FILENAME              F("/eth_cred.dat") 
        
           ////////////////////////////////////////////////////////////// 
        
           // Indicates whether ESP has credentials saved from previous session, or double reset detected 
        
           bool initialConfig = false; 
        
           // Use false if you don't like to display Available Pages in Information Page of Config Portal 
        
           // Comment out or use true to display Available Pages in Information Page of Config Portal 
        
           // Must be placed before #include <AsyncESP32_Ethernet_Manager.h> 
        
           #define USE_AVAILABLE_PAGES     true 
        
           // From v1.0.10 to permit disable/enable StaticIP configuration in Config Portal from sketch. Valid only if DHCP is used. 
        
           // You'll loose the feature of dynamically changing from DHCP to static IP, or vice versa 
        
           // You have to explicitly specify false to disable the feature. 
        
           //#define USE_STATIC_IP_CONFIG_IN_CP          false 
        
           // Use false to disable NTP config. Advisable when using Cellphone, Tablet to access Config Portal. 
        
           // See Issue 23: On Android phone ConfigPortal is unresponsive (https://github.com/khoih-prog/ESP_WiFiManager/issues/23) 
        
           #define USE_ESP_ETH_MANAGER_NTP     true 
        
           // Just use enough to save memory. On ESP8266, can cause blank ConfigPortal screen 
        
           // if using too much memory 
        
           #define USING_AFRICA        false 
        
           #define USING_AMERICA       true 
        
           #define USING_ANTARCTICA    false 
        
           #define USING_ASIA          false 
        
           #define USING_ATLANTIC      false 
        
           #define USING_AUSTRALIA     false 
        
           #define USING_EUROPE        false 
        
           #define USING_INDIAN        false 
        
           #define USING_PACIFIC       false 
        
           #define USING_ETC_GMT       false 
        
           // Use true to enable CloudFlare NTP service. System can hang if you don't have Internet access while accessing CloudFlare 
        
           // See Issue #21: CloudFlare link in the default portal (https://github.com/khoih-prog/ESP_WiFiManager/issues/21) 
        
           #define USE_CLOUDFLARE_NTP          false 
        
           // New in v1.0.11 
        
           #define USING_CORS_FEATURE          true 
        
           ////////////////////////////////////////////////////////////// 
        
           // Use USE_DHCP_IP == true for dynamic DHCP IP, false to use static IP which you have to change accordingly to your network 
        
           #if (defined(USE_STATIC_IP_CONFIG_IN_CP) && !USE_STATIC_IP_CONFIG_IN_CP) 
        
             // Force DHCP to be true 
        
             #if defined(USE_DHCP_IP) 
        
               #undef USE_DHCP_IP 
        
             #endif 
        
             #define USE_DHCP_IP     true 
        
           #else 
        
             // You can select DHCP or Static IP here 
        
             //#define USE_DHCP_IP     true 
        
             #define USE_DHCP_IP     false 
        
           #endif 
        
           #if ( USE_DHCP_IP ) 
        
             // Use DHCP 
        
             #if (_ESPASYNC_ETH_MGR_LOGLEVEL_ > 3) 
        
               #warning Using DHCP IP 
        
             #endif 
        
             IPAddress stationIP   = IPAddress(0, 0, 0, 0); 
        
             IPAddress gatewayIP   = IPAddress(192, 168, 2, 1); 
        
             IPAddress netMask     = IPAddress(255, 255, 255, 0); 
        
           #else 
        
             // Use static IP 
        
             #if (_ESPASYNC_ETH_MGR_LOGLEVEL_ > 3) 
        
               #warning Using static IP 
        
             #endif 
        
             IPAddress stationIP   = IPAddress(192, 168, 2, 232); 
        
             IPAddress gatewayIP   = IPAddress(192, 168, 2, 1); 
        
             IPAddress netMask     = IPAddress(255, 255, 255, 0); 
        
           #endif 
        
           ////////////////////////////////////////////////////////////// 
        
           #define USE_CONFIGURABLE_DNS      true 
        
           IPAddress dns1IP      = gatewayIP; 
        
           IPAddress dns2IP      = IPAddress(8, 8, 8, 8); 
        
           #include <AsyncESP32_Ethernet_Manager.h>               //https://github.com/khoih-prog/AsyncESP32_Ethernet_Manager 
        
           #define HTTP_PORT     80 
        
           ////////////////////////////////////////////////////////////// 
        
           /****************************************** 
        
              // Defined in AsyncESP32_Ethernet_Manager.hpp 
        
             typedef struct 
        
             { 
        
               IPAddress _sta_static_ip; 
        
               IPAddress _sta_static_gw; 
        
               IPAddress _sta_static_sn; 
        
               #if USE_CONFIGURABLE_DNS 
        
               IPAddress _sta_static_dns1; 
        
               IPAddress _sta_static_dns2; 
        
               #endif 
        
             }  ETH_STA_IPConfig; 
        
           ******************************************/ 
        
           ETH_STA_IPConfig EthSTA_IPconfig; 
        
           ////////////////////////////////////////////////////////////// 
        
           void initSTAIPConfigStruct(ETH_STA_IPConfig &in_EthSTA_IPconfig) 
        
           { 
        
             in_EthSTA_IPconfig._sta_static_ip   = stationIP; 
        
             in_EthSTA_IPconfig._sta_static_gw   = gatewayIP; 
        
             in_EthSTA_IPconfig._sta_static_sn   = netMask; 
        
           #if USE_CONFIGURABLE_DNS 
        
             in_EthSTA_IPconfig._sta_static_dns1 = dns1IP; 
        
             in_EthSTA_IPconfig._sta_static_dns2 = dns2IP; 
        
           #endif 
        
           } 
        
           ////////////////////////////////////////////////////////////// 
        
           void displayIPConfigStruct(ETH_STA_IPConfig in_EthSTA_IPconfig) 
        
           { 
        
             LOGERROR3(F("stationIP ="), in_EthSTA_IPconfig._sta_static_ip, ", gatewayIP =", in_EthSTA_IPconfig._sta_static_gw); 
        
             LOGERROR1(F("netMask ="), in_EthSTA_IPconfig._sta_static_sn); 
        
           #if USE_CONFIGURABLE_DNS 
        
             LOGERROR3(F("dns1IP ="), in_EthSTA_IPconfig._sta_static_dns1, ", dns2IP =", in_EthSTA_IPconfig._sta_static_dns2); 
        
           #endif 
        
           } 
        
           ////////////////////////////////////////////////////////////// 
        
           void toggleLED() 
        
           { 
        
             //toggle state 
        
             digitalWrite(LED_BUILTIN, !digitalRead(LED_BUILTIN)); 
        
           } 
        
           ////////////////////////////////////////////////////////////// 
        
           #if USE_ESP_ETH_MANAGER_NTP 
        
           void printLocalTime() 
        
           { 
        
             struct tm timeinfo; 
        
             getLocalTime( &timeinfo ); 
        
             // Valid only if year > 2000. 
        
             // You can get from timeinfo : tm_year, tm_mon, tm_mday, tm_hour, tm_min, tm_sec 
        
             if (timeinfo.tm_year > 100 ) 
        
             { 
        
               Serial.print("Local Date/Time: "); 
        
               Serial.print( asctime( &timeinfo ) ); 
        
             } 
        
           } 
        
           #endif 
        
           ////////////////////////////////////////////////////////////// 
        
           void heartBeatPrint() 
        
           { 
        
           #if USE_ESP_ETH_MANAGER_NTP 
        
             printLocalTime(); 
        
           #else 
        
             static int num = 1; 
        
           #if USING_W5500 
        
             if (ESP32_W5500_isConnected()) 
        
           #else 
        
             if (ESP32_ENC_isConnected()) 
        
           #endif 
        
               Serial.print(F("H"));        // H means connected to Ethernet 
        
             else 
        
               Serial.print(F("F"));        // F means not connected to Ethernet 
        
             if (num == 80) 
        
             { 
        
               Serial.println(); 
        
               num = 1; 
        
             } 
        
             else if (num++ % 10 == 0) 
        
             { 
        
               Serial.print(F(" ")); 
        
             } 
        
           #endif 
        
           } 
        
           ////////////////////////////////////////////////////////////// 
        
           void check_status() 
        
           { 
        
             static ulong checkstatus_timeout  = 0; 
        
             static ulong LEDstatus_timeout    = 0; 
        
             static ulong current_millis; 
        
           #if USE_ESP_ETH_MANAGER_NTP 
        
           #define HEARTBEAT_INTERVAL    60000L 
        
           #else 
        
           #define HEARTBEAT_INTERVAL    10000L 
        
           #endif 
        
           #define LED_INTERVAL          2000L 
        
             current_millis = millis(); 
        
             if ((current_millis > LEDstatus_timeout) || (LEDstatus_timeout == 0)) 
        
             { 
        
               // Toggle LED at LED_INTERVAL = 2s 
        
               toggleLED(); 
        
               LEDstatus_timeout = current_millis + LED_INTERVAL; 
        
             } 
        
             // Print hearbeat every HEARTBEAT_INTERVAL (10) seconds. 
        
             if ((current_millis > checkstatus_timeout) || (checkstatus_timeout == 0)) 
        
             { 
        
               heartBeatPrint(); 
        
               checkstatus_timeout = current_millis + HEARTBEAT_INTERVAL; 
        
             } 
        
           } 
        
           ////////////////////////////////////////////////////////////// 
        
           int calcChecksum(uint8_t* address, uint16_t sizeToCalc) 
        
           { 
        
             uint16_t checkSum = 0; 
        
             for (uint16_t index = 0; index < sizeToCalc; index++) 
        
             { 
        
               checkSum += * ( ( (byte*) address ) + index); 
        
             } 
        
             return checkSum; 
        
           } 
        
           ////////////////////////////////////////////////////////////// 
        
           bool loadConfigData() 
        
           { 
        
             File file = FileFS.open(CONFIG_FILENAME, "r"); 
        
             LOGERROR(F("LoadCfgFile ")); 
        
             memset((void *) &Ethconfig,       0, sizeof(Ethconfig)); 
        
             memset((void *) &EthSTA_IPconfig, 0, sizeof(EthSTA_IPconfig)); 
        
             if (file) 
        
             { 
        
               file.readBytes((char *) &Ethconfig,   sizeof(Ethconfig)); 
        
               file.readBytes((char *) &EthSTA_IPconfig, sizeof(EthSTA_IPconfig)); 
        
               file.close(); 
        
               LOGERROR(F("OK")); 
        
               if ( Ethconfig.checksum != calcChecksum( (uint8_t*) &Ethconfig, sizeof(Ethconfig) - sizeof(Ethconfig.checksum) ) ) 
        
               { 
        
                 LOGERROR(F("Ethconfig checksum wrong")); 
        
                 return false; 
        
               } 
        
               displayIPConfigStruct(EthSTA_IPconfig); 
        
               return true; 
        
             } 
        
             else 
        
             { 
        
               LOGERROR(F("failed")); 
        
               return false; 
        
             } 
        
           } 
        
           ////////////////////////////////////////////////////////////// 
        
           void saveConfigData() 
        
           { 
        
             File file = FileFS.open(CONFIG_FILENAME, "w"); 
        
             LOGERROR(F("SaveCfgFile ")); 
        
             if (file) 
        
             { 
        
               Ethconfig.checksum = calcChecksum( (uint8_t*) &Ethconfig, sizeof(Ethconfig) - sizeof(Ethconfig.checksum) ); 
        
               file.write((uint8_t*) &Ethconfig, sizeof(Ethconfig)); 
        
               displayIPConfigStruct(EthSTA_IPconfig); 
        
               file.write((uint8_t*) &EthSTA_IPconfig, sizeof(EthSTA_IPconfig)); 
        
               file.close(); 
        
               LOGERROR(F("OK")); 
        
             } 
        
             else 
        
             { 
        
               LOGERROR(F("failed")); 
        
             } 
        
           } 
        
           ////////////////////////////////////////////////////////////// 
        
           #if USING_W5500 
        
           void beginEthernet() 
        
           { 
        
             LOGWARN(F("Default SPI pinout:")); 
        
             LOGWARN1(F("SPI_HOST:"), ETH_SPI_HOST); 
        
             LOGWARN1(F("MOSI:"), MOSI_GPIO); 
        
             LOGWARN1(F("MISO:"), MISO_GPIO); 
        
             LOGWARN1(F("SCK:"),  SCK_GPIO); 
        
             LOGWARN1(F("CS:"),   CS_GPIO); 
        
             LOGWARN1(F("INT:"),  INT_GPIO); 
        
             LOGWARN1(F("SPI Clock (MHz):"), SPI_CLOCK_MHZ); 
        
             LOGWARN(F("=========================")); 
        
             /////////////////////////////////// 
        
             // To be called before ETH.begin() 
        
             ESP32_W5500_onEvent(); 
        
             // start the ethernet connection and the server: 
        
             // Use DHCP dynamic IP and random mac 
        
             uint16_t index = millis() % NUMBER_OF_MAC; 
        
             //bool begin(int MISO_GPIO, int MOSI_GPIO, int SCLK_GPIO, int CS_GPIO, int INT_GPIO, int SPI_CLOCK_MHZ, 
        
             //           int SPI_HOST, uint8_t *W5500_Mac = W5500_Default_Mac); 
        
             //ETH.begin( MISO_GPIO, MOSI_GPIO, SCK_GPIO, CS_GPIO, INT_GPIO, SPI_CLOCK_MHZ, ETH_SPI_HOST ); 
        
             ETH.begin( MISO_GPIO, MOSI_GPIO, SCK_GPIO, CS_GPIO, INT_GPIO, SPI_CLOCK_MHZ, ETH_SPI_HOST, mac[index] ); 
        
           } 
        
           void initEthernet() 
        
           { 
        
           #if !( USE_DHCP_IP ) 
        
             displayIPConfigStruct(EthSTA_IPconfig); 
        
             // Static IP, leave without this line to get IP via DHCP 
        
             //bool config(IPAddress local_ip, IPAddress gateway, IPAddress subnet, IPAddress dns1 = 0, IPAddress dns2 = 0); 
        
             //ETH.config(stationIP, gatewayIP, netMask, dns1IP, dns2IP); 
        
             ETH.config(EthSTA_IPconfig._sta_static_ip, EthSTA_IPconfig._sta_static_gw, EthSTA_IPconfig._sta_static_sn, 
        
                        EthSTA_IPconfig._sta_static_dns1); 
        
           #endif 
        
             ESP32_W5500_waitForConnect(); 
        
           } 
        
           #else 
        
           void beginEthernet() 
        
           { 
        
             LOGWARN(F("Default SPI pinout:")); 
        
             LOGWARN1(F("MOSI:"), MOSI_GPIO); 
        
             LOGWARN1(F("MISO:"), MISO_GPIO); 
        
             LOGWARN1(F("SCK:"),  SCK_GPIO); 
        
             LOGWARN1(F("CS:"),   CS_GPIO); 
        
             LOGWARN1(F("INT:"),  INT_GPIO); 
        
             LOGWARN1(F("SPI Clock (MHz):"), SPI_CLOCK_MHZ); 
        
             LOGWARN(F("=========================")); 
        
             /////////////////////////////////// 
        
             // To be called before ETH.begin() 
        
             ESP32_ENC_onEvent(); 
        
             // start the ethernet connection and the server: 
        
             // Use DHCP dynamic IP and random mac 
        
             uint16_t index = millis() % NUMBER_OF_MAC; 
        
             //bool begin(int MISO_GPIO, int MOSI_GPIO, int SCLK_GPIO, int CS_GPIO, int INT_GPIO, int SPI_CLOCK_MHZ, 
        
             //           int SPI_HOST, uint8_t *ENC28J60_Mac = ENC28J60_Default_Mac); 
        
             //ETH.begin( MISO_GPIO, MOSI_GPIO, SCK_GPIO, CS_GPIO, INT_GPIO, SPI_CLOCK_MHZ, SPI_HOST ); 
        
             ETH.begin( MISO_GPIO, MOSI_GPIO, SCK_GPIO, CS_GPIO, INT_GPIO, SPI_CLOCK_MHZ, SPI_HOST, mac[index] ); 
        
           } 
        
           void initEthernet() 
        
           { 
        
           #if !( USE_DHCP_IP ) 
        
             displayIPConfigStruct(EthSTA_IPconfig); 
        
             // Static IP, leave without this line to get IP via DHCP 
        
             //bool config(IPAddress local_ip, IPAddress gateway, IPAddress subnet, IPAddress dns1 = 0, IPAddress dns2 = 0); 
        
             //ETH.config(stationIP, gatewayIP, netMask, dns1IP, dns2IP); 
        
             ETH.config(EthSTA_IPconfig._sta_static_ip, EthSTA_IPconfig._sta_static_gw, EthSTA_IPconfig._sta_static_sn, 
        
                        EthSTA_IPconfig._sta_static_dns1); 
        
           #endif 
        
             ESP32_ENC_waitForConnect(); 
        
           } 
        
           #endif 
        
           ////////////////////////////////////////////////////////////// 
        
           void setup() 
        
           { 
        
             //set led pin as output 
        
             pinMode(LED_BUILTIN, OUTPUT); 
        
             pinMode(TRIGGER_PIN, INPUT_PULLUP); 
        
             pinMode(TRIGGER_PIN2, INPUT_PULLUP); 
        
             Serial.begin(115200); 
        
             while (!Serial && millis() < 5000); 
        
             delay(200); 
        
             Serial.print(F("\nStarting Async_ConfigOnSwitch using ")); 
        
             Serial.print(FS_Name); 
        
             Serial.print(F(" on ")); 
        
             Serial.print(ARDUINO_BOARD); 
        
             Serial.print(F(" with ")); 
        
             Serial.println(SHIELD_TYPE); 
        
             Serial.println(ASYNC_ESP32_ETH_MANAGER_VERSION); 
        
             Serial.setDebugOutput(false); 
        
             if (FORMAT_FILESYSTEM) 
        
               FileFS.format(); 
        
             // Format FileFS if not yet 
        
           #ifdef ESP32 
        
             if (!FileFS.begin(true)) 
        
           #else 
        
             if (!FileFS.begin()) 
        
           #endif 
        
             { 
        
           #ifdef ESP8266 
        
               FileFS.format(); 
        
           #endif 
        
               Serial.println(F("SPIFFS/LittleFS failed! Already tried formatting.")); 
        
               if (!FileFS.begin()) 
        
               { 
        
                 // prevents debug info from the library to hide err message. 
        
                 delay(100); 
        
           #if USE_LITTLEFS 
        
                 Serial.println(F("LittleFS failed!. Please use SPIFFS or EEPROM. Stay forever")); 
        
           #else 
        
                 Serial.println(F("SPIFFS failed!. Please use LittleFS or EEPROM. Stay forever")); 
        
           #endif 
        
                 while (true) 
        
                 { 
        
                   delay(1); 
        
                 } 
        
               } 
        
             } 
        
             unsigned long startedAt = millis(); 
        
             beginEthernet(); 
        
             initSTAIPConfigStruct(EthSTA_IPconfig); 
        
             digitalWrite(LED_BUILTIN, LED_ON); // turn the LED on by making the voltage LOW to tell us we are in configuration mode. 
        
             //Local intialization. Once its business is done, there is no need to keep it around 
        
             // Use this to default DHCP hostname to ESP32-XXXXXX 
        
             //AsyncESP32_Ethernet_Manager AsyncESP32_Ethernet_manager(&webServer, &dnsServer); 
        
             // Use this to personalize DHCP hostname (RFC952 conformed) 
        
             AsyncWebServer webServer(HTTP_PORT); 
        
           #if ( USING_ESP32_S2 || USING_ESP32_C3 ) 
        
             AsyncESP32_Ethernet_Manager AsyncESP32_Ethernet_manager(&webServer, NULL, "AsyncConfigOnSwitch"); 
        
           #else 
        
             AsyncDNSServer dnsServer; 
        
             AsyncESP32_Ethernet_Manager AsyncESP32_Ethernet_manager(&webServer, &dnsServer, "AsyncConfigOnSwitch"); 
        
           #endif 
        
             AsyncESP32_Ethernet_manager.setDebugOutput(true); 
        
           #if !USE_DHCP_IP 
        
             // Set (static IP, Gateway, Subnetmask, DNS1 and DNS2) or (IP, Gateway, Subnetmask) 
        
             AsyncESP32_Ethernet_manager.setSTAStaticIPConfig(EthSTA_IPconfig); 
        
           #endif 
        
           #if USING_CORS_FEATURE 
        
             AsyncESP32_Ethernet_manager.setCORSHeader("Your Access-Control-Allow-Origin"); 
        
           #endif 
        
             bool configDataLoaded = false; 
        
             if (loadConfigData()) 
        
             { 
        
               configDataLoaded = true; 
        
               AsyncESP32_Ethernet_manager.setConfigPortalTimeout( 
        
                 120); //If no access point name has been previously entered disable timeout. 
        
               Serial.println(F("Got stored Credentials. Timeout 120s for Config Portal")); 
        
           #if USE_ESP_ETH_MANAGER_NTP 
        
               if ( strlen(Ethconfig.TZ_Name) > 0 ) 
        
               { 
        
                 LOGERROR3(F("Current TZ_Name ="), Ethconfig.TZ_Name, F(", TZ = "), Ethconfig.TZ); 
        
                 //configTzTime(Ethconfig.TZ, "pool.ntp.org" ); 
        
                 configTzTime(Ethconfig.TZ, "time.nist.gov", "0.pool.ntp.org", "1.pool.ntp.org"); 
        
               } 
        
               else 
        
               { 
        
                 Serial.println(F("Current Timezone is not set. Enter Config Portal to set.")); 
        
               } 
        
           #endif 
        
             } 
        
             else 
        
             { 
        
               // Enter CP only if no stored SSID on flash and file 
        
               Serial.println(F("Open Config Portal without Timeout: No stored Credentials.")); 
        
               initialConfig = true; 
        
             } 
        
             ////////////////////////////////// 
        
             // Connect ETH now if using STA 
        
             initEthernet(); 
        
             ////////////////////////////////// 
        
             if (initialConfig) 
        
             { 
        
               Serial.print(F("Starting configuration portal @ ")); 
        
               Serial.println(ETH.localIP()); 
        
               digitalWrite(LED_BUILTIN, LED_ON); // Turn led on as we are in configuration mode. 
        
               //sets timeout in seconds until configuration portal gets turned off. 
        
               //If not specified device will remain in configuration mode until 
        
               //switched off via webserver or device is restarted. 
        
               //AsyncESP32_Ethernet_manager.setConfigPortalTimeout(600); 
        
               // Starts an access point 
        
               if (!AsyncESP32_Ethernet_manager.startConfigPortal()) 
        
                 Serial.println(F("Not connected to ETH network but continuing anyway.")); 
        
               else 
        
               { 
        
                 Serial.println(F("ETH network connected...yeey :)")); 
        
               } 
        
           #if USE_ESP_ETH_MANAGER_NTP 
        
               String tempTZ   = AsyncESP32_Ethernet_manager.getTimezoneName(); 
        
               if (strlen(tempTZ.c_str()) < sizeof(Ethconfig.TZ_Name) - 1) 
        
                 strcpy(Ethconfig.TZ_Name, tempTZ.c_str()); 
        
               else 
        
                 strncpy(Ethconfig.TZ_Name, tempTZ.c_str(), sizeof(Ethconfig.TZ_Name) - 1); 
        
               const char * TZ_Result = AsyncESP32_Ethernet_manager.getTZ(Ethconfig.TZ_Name); 
        
               if (strlen(TZ_Result) < sizeof(Ethconfig.TZ) - 1) 
        
                 strcpy(Ethconfig.TZ, TZ_Result); 
        
               else 
        
                 strncpy(Ethconfig.TZ, TZ_Result, sizeof(Ethconfig.TZ_Name) - 1); 
        
               if ( strlen(Ethconfig.TZ_Name) > 0 ) 
        
               { 
        
                 LOGERROR3(F("Saving current TZ_Name ="), Ethconfig.TZ_Name, F(", TZ = "), Ethconfig.TZ); 
        
                 //configTzTime(Ethconfig.TZ, "pool.ntp.org" ); 
        
                 configTzTime(Ethconfig.TZ, "time.nist.gov", "0.pool.ntp.org", "1.pool.ntp.org"); 
        
               } 
        
               else 
        
               { 
        
                 LOGERROR(F("Current Timezone Name is not set. Enter Config Portal to set.")); 
        
               } 
        
           #endif 
        
               AsyncESP32_Ethernet_manager.getSTAStaticIPConfig(EthSTA_IPconfig); 
        
               saveConfigData(); 
        
             } 
        
             digitalWrite(LED_BUILTIN, LED_OFF); // Turn led off as we are not in configuration mode. 
        
             startedAt = millis(); 
        
             Serial.print(F("After waiting ")); 
        
             Serial.print((float) (millis() - startedAt) / 1000); 
        
             Serial.print(F(" secs more in setup(), connection result is ")); 
        
           #if USING_W5500 
        
             if (ESP32_W5500_isConnected()) 
        
           #else 
        
             if (ESP32_ENC_isConnected()) 
        
           #endif 
        
             { 
        
               Serial.print(F("connected. Local IP: ")); 
        
               Serial.println(ETH.localIP()); 
        
             } 
        
           } 
        
           ////////////////////////////////////////////////////////////// 
        
           void loop() 
        
           { 
        
             // is configuration portal requested? 
        
             if ((digitalRead(TRIGGER_PIN) == LOW) || (digitalRead(TRIGGER_PIN2) == LOW)) 
        
             { 
        
               Serial.println(F("\nConfiguration portal requested.")); 
        
               digitalWrite(LED_BUILTIN, LED_ON); // turn the LED on by making the voltage LOW to tell us we are in configuration mode. 
        
               //Local intialization. Once its business is done, there is no need to keep it around 
        
               // Use this to default DHCP hostname to ESP32-XXXXXX 
        
               //AsyncESP32_Ethernet_Manager AsyncESP32_Ethernet_manager(&webServer, &dnsServer); 
        
               // Use this to personalize DHCP hostname (RFC952 conformed) 
        
               AsyncWebServer webServer(HTTP_PORT); 
        
           #if ( USING_ESP32_S2 || USING_ESP32_C3 ) 
        
               AsyncESP32_Ethernet_Manager AsyncESP32_Ethernet_manager(&webServer, NULL, "ConfigOnSwitch"); 
        
           #else 
        
               AsyncDNSServer dnsServer; 
        
               AsyncESP32_Ethernet_Manager AsyncESP32_Ethernet_manager(&webServer, &dnsServer, "ConfigOnSwitch"); 
        
           #endif 
        
           #if !USE_DHCP_IP 
        
           #if USE_CONFIGURABLE_DNS 
        
               // Set static IP, Gateway, Subnetmask, DNS1 and DNS2 
        
               AsyncESP32_Ethernet_manager.setSTAStaticIPConfig(stationIP, gatewayIP, netMask, dns1IP, dns2IP); 
        
           #else 
        
               // Set static IP, Gateway, Subnetmask, Use auto DNS1 and DNS2. 
        
               AsyncESP32_Ethernet_manager.setSTAStaticIPConfig(stationIP, gatewayIP, netMask); 
        
           #endif 
        
           #endif 
        
           #if USING_CORS_FEATURE 
        
               AsyncESP32_Ethernet_manager.setCORSHeader("Your Access-Control-Allow-Origin"); 
        
           #endif 
        
               //Check if there is stored credentials. 
        
               //If not found, device will remain in configuration mode until switched off via webserver. 
        
               Serial.println(F("Opening configuration portal. ")); 
        
               if (loadConfigData()) 
        
               { 
        
                 AsyncESP32_Ethernet_manager.setConfigPortalTimeout( 
        
                   120); //If no access point name has been previously entered disable timeout. 
        
                 Serial.println(F("Got stored Credentials. Timeout 120s for Config Portal")); 
        
               } 
        
               else 
        
               { 
        
                 // Enter CP only if no stored SSID on flash and file 
        
                 AsyncESP32_Ethernet_manager.setConfigPortalTimeout(0); 
        
                 Serial.println(F("Open Config Portal without Timeout: No stored Credentials.")); 
        
                 initialConfig = true; 
        
               } 
        
               //Starts an access point 
        
               //and goes into a blocking loop awaiting configuration 
        
               if (!AsyncESP32_Ethernet_manager.startConfigPortal()) 
        
                 Serial.println(F("Not connected to ETH network but continuing anyway.")); 
        
               else 
        
               { 
        
                 Serial.println(F("ETH network connected...yeey :)")); 
        
                 Serial.print(F("Local IP: ")); 
        
                 Serial.println(ETH.localIP()); 
        
               } 
        
           #if USE_ESP_ETH_MANAGER_NTP 
        
               String tempTZ = AsyncESP32_Ethernet_manager.getTimezoneName(); 
        
               if (strlen(tempTZ.c_str()) < sizeof(Ethconfig.TZ_Name) - 1) 
        
                 strcpy(Ethconfig.TZ_Name, tempTZ.c_str()); 
        
               else 
        
                 strncpy(Ethconfig.TZ_Name, tempTZ.c_str(), sizeof(Ethconfig.TZ_Name) - 1); 
        
               const char * TZ_Result = AsyncESP32_Ethernet_manager.getTZ(Ethconfig.TZ_Name); 
        
               if (strlen(TZ_Result) < sizeof(Ethconfig.TZ) - 1) 
        
                 strcpy(Ethconfig.TZ, TZ_Result); 
        
               else 
        
                 strncpy(Ethconfig.TZ, TZ_Result, sizeof(Ethconfig.TZ_Name) - 1); 
        
               if ( strlen(Ethconfig.TZ_Name) > 0 ) 
        
               { 
        
                 LOGERROR3(F("Saving current TZ_Name ="), Ethconfig.TZ_Name, F(", TZ = "), Ethconfig.TZ); 
        
                 //configTzTime(Ethconfig.TZ, "pool.ntp.org" ); 
        
                 configTzTime(Ethconfig.TZ, "time.nist.gov", "0.pool.ntp.org", "1.pool.ntp.org"); 
        
               } 
        
               else 
        
               { 
        
                 LOGERROR(F("Current Timezone Name is not set. Enter Config Portal to set.")); 
        
               } 
        
           #endif 
        
               AsyncESP32_Ethernet_manager.getSTAStaticIPConfig(EthSTA_IPconfig); 
        
               saveConfigData(); 
        
           #if !USE_DHCP_IP 
        
               // Reset to use new Static IP, if different from current ETH.localIP() 
        
               if (ETH.localIP() != EthSTA_IPconfig._sta_static_ip) 
        
               { 
        
                 Serial.print(F("Current IP = ")); 
        
                 Serial.print(ETH.localIP()); 
        
                 Serial.print(F(". Reset to take new IP = ")); 
        
                 Serial.println(EthSTA_IPconfig._sta_static_ip); 
        
                 ESP.restart(); 
        
                 delay(2000); 
        
               } 
        
           #endif 
        
               digitalWrite(LED_BUILTIN, LED_OFF); // Turn led off as we are not in configuration mode. 
        
             } 
        
             // put your main code here, to run repeatedly 
        
             check_status(); 
        
           }

Debug Terminal Output Samples

1. Async_ConfigOnDoubleReset using LittleFS on ESP32_DEV with ESP32_ENC28J60

This is terminal debug output when running Async_ConfigOnDoubleReset on ESP32_ENC28J60.

Starting Async_ConfigOnDoubleReset using LittleFS on ESP32_DEV with ESP32_ENC28J60
AsyncESP32_Ethernet_Manager v1.0.0
ESP_DoubleResetDetector v1.3.2
[EM] Default SPI pinout:
[EM] MOSI: 23
[EM] MISO: 19
[EM] SCK: 18
[EM] CS: 5
[EM] INT: 4
[EM] SPI Clock (MHz): 8
[EM] =========================

ETH Started
[EM] RFC925 Hostname = AsyncConfigOnDoubleReset
[EM] setSTAStaticIPConfig
[EM] Set CORS Header to :  Your Access-Control-Allow-Origin
[EM] LoadCfgFile 
[EM] OK
[EM] stationIP = 192.168.2.233 , gatewayIP = 192.168.2.1
[EM] netMask = 255.255.255.0
[EM] dns1IP = 192.168.2.1 , dns2IP = 8.8.8.8
Got stored Credentials. Timeout 120s for Config Portal
[EM] Current TZ_Name = America/New_York , TZ =  EST5EDT,M3.2.0,M11.1.0
[EM] stationIP = 192.168.2.233 , gatewayIP = 192.168.2.1
[EM] netMask = 255.255.255.0
[EM] dns1IP = 192.168.2.1 , dns2IP = 8.8.8.8
ETH Connected
ETH MAC: DE:AD:BE:EF:FE:11, IPv4: 192.168.2.233
FULL_DUPLEX, 10Mbps
LittleFS Flag read = 0xD0D04321
No doubleResetDetected
Saving config file...
Saving config file OK
After waiting 0.00 secs more in setup(), connection result is connected. Local IP: 192.168.2.233
[EM] freeing allocated params!
Local Date/Time: Sun Dec 11 23:03:36 2022
Stop doubleResetDetecting
Saving config file...
Saving config file OK
Local Date/Time: Sun Dec 11 23:04:35 2022
Local Date/Time: Sun Dec 11 23:05:35 2022

2. Async_ConfigOnSwichFS using LittleFS on ESP32_DEV with ESP32_W5500

This is terminal debug output when running Async_ConfigOnSwichFS on ESP32_W5500. Config Portal was requested to input and save Credentials.

Starting Async_ConfigOnSwichFS using LittleFS on ESP32_DEV with ESP32_W5500
AsyncESP32_Ethernet_Manager v1.0.0
[EM] Default SPI pinout:
[EM] SPI_HOST: 2
[EM] MOSI: 23
[EM] MISO: 19
[EM] SCK: 18
[EM] CS: 5
[EM] INT: 4
[EM] SPI Clock (MHz): 25
[EM] =========================

ETH Started
Configuration file not found
Failed to read ConfigFile, using default values
[EM] RFC925 Hostname = ConfigOnSwitchFS
[EM] setSTAStaticIPConfig
[EM] Set CORS Header to :  Your Access-Control-Allow-Origin
[EM] LoadCfgFile 
[EM] OK
[EM] stationIP = 192.168.2.232 , gatewayIP = 192.168.2.1
[EM] netMask = 255.255.255.0
[EM] dns1IP = 192.168.2.1 , dns2IP = 8.8.8.8
Got stored Credentials. Timeout 120s for Config Portal
[EM] Current TZ_Name = America/New_York , TZ =  EST5EDT,M3.2.0,M11.1.0
[EM] stationIP = 192.168.2.232 , gatewayIP = 192.168.2.1
[EM] netMask = 255.255.255.0
[EM] dns1IP = 192.168.2.1 , dns2IP = 8.8.8.8
ETH Connected
ETH MAC: DE:AD:BE:EF:FE:07, IPv4: 192.168.2.232
FULL_DUPLEX, 100Mbps
After waiting 0.00 secs more in setup(), connection result is connected. Local IP: 192.168.2.232
[EM] freeing allocated params!
Local Date/Time: Thu Dec  8 16:31:38 2022

Configuration portal requested.
[EM] RFC925 Hostname = ConfigOnSwitchFS
Opening configuration portal. 
[EM] LoadCfgFile 
[EM] OK
[EM] stationIP = 192.168.2.232 , gatewayIP = 192.168.2.1
[EM] netMask = 255.255.255.0
[EM] dns1IP = 192.168.2.1 , dns2IP = 8.8.8.8
Got stored Credentials. Timeout 120s for Config Portal
[EM] Adding parameter thingspeakApiKey
[EM] Adding parameter SensorDHT22
[EM] Adding parameter PinSda
[EM] Adding parameter PinScl
[EM] setSTAStaticIPConfig for USE_CONFIGURABLE_DNS
[EM] Set CORS Header to :  Your Access-Control-Allow-Origin
[EM] _configPortalStart millis() = 17427
[EM] Config Portal IP address = 192.168.2.232
[EM] HTTP server started
[EM] startConfigPortal : Enter loop
[EM] handleRoot
[EM] request host IP = 192.168.2.232
[EM] Handle ETH
[EM] Static IP = 192.168.2.232
[EM] Sent config page
[EM] ETH save
[EM] TZ = America/New_York
[EM] Parameter and value : thingspeakApiKey API_Key
[EM] Parameter and value : SensorDHT22 T
[EM] Parameter and value : PinSda 21
[EM] Parameter and value : PinScl 22
[EM] New Static IP = 192.168.2.233
[EM] New Static Gateway = 192.168.2.1
[EM] New Static Netmask = 255.255.255.0
[EM] New Static DNS1 = 192.168.2.1
[EM] New Static DNS2 = 8.8.8.8
[EM] Sent eth save page
[EM] stopConfigPortal
[EM] startConfigPortal: exit, _configPortalTimeout = 0 millis() = 67391
ETH network connected...yeey :)
Local IP: 192.168.2.232
[EM] Saving current TZ_Name = America/New_York , TZ =  EST5EDT,M3.2.0,M11.1.0
[EM] getSTAStaticIPConfig
[EM] SaveCfgFile 
[EM] stationIP = 192.168.2.233 , gatewayIP = 192.168.2.1
[EM] netMask = 255.255.255.0
[EM] dns1IP = 192.168.2.1 , dns2IP = 8.8.8.8
[EM] OK
Saving config file
{
  "thingspeakApiKey": "API_Key",
  "SensorDHT22": true,
  "PinSda": 21,
  "PinScl": 22
}
Config file was successfully saved
[EM] freeing allocated params!
Local Date/Time: Sun Dec 11 23:04:35 2022
Local Date/Time: Sun Dec 11 23:05:35 2022

3. Async_ESP32_FSWebServer_DRD using LittleFS on ESP32_DEV with ESP32_W5500

This is terminal debug output when running Async_ESP32_FSWebServer_DRD on ESP32_W5500. Config Portal was requested by DRD (also using LittleFS) to input and save Credentials.

Starting Async_ESP32_FSWebServer_DRD using LittleFS on ESP32_DEV with ESP32_W5500
AsyncESP32_Ethernet_Manager v1.0.0
ESP_DoubleResetDetector v1.3.2
FS File: CanadaFlag_1.png, size: 40.25KB
FS File: CanadaFlag_2.png, size: 8.12KB
FS File: CanadaFlag_3.jpg, size: 10.89KB
FS File: drd.dat, size: 4B
FS File: edit.htm.gz, size: 4.02KB
FS File: eth_cred.dat, size: 142B
FS File: favicon.ico, size: 1.12KB
FS File: graphs.js.gz, size: 1.92KB
FS File: index.htm, size: 3.63KB
FS File: wifi_cred.dat, size: 142B

[EM] Default SPI pinout:
[EM] SPI_HOST: 2
[EM] MOSI: 23
[EM] MISO: 19
[EM] SCK: 18
[EM] CS: 5
[EM] INT: 4
[EM] SPI Clock (MHz): 25
[EM] =========================

ETH Started
[EM] RFC925 Hostname = AsyncESP32-FSWebServer
[EM] setSTAStaticIPConfig
[EM] Set CORS Header to :  Your Access-Control-Allow-Origin
[EM] LoadCfgFile 
[EM] OK
[EM] stationIP = 192.168.2.232 , gatewayIP = 192.168.2.1
[EM] netMask = 255.255.255.0
[EM] dns1IP = 192.168.2.1 , dns2IP = 8.8.8.8
[EM] stationIP = 192.168.2.232 , gatewayIP = 192.168.2.1
[EM] netMask = 255.255.255.0
[EM] dns1IP = 192.168.2.1 , dns2IP = 8.8.8.8
ETH Connected
ETH MAC: DE:AD:BE:EF:FE:07, IPv4: 192.168.2.232
FULL_DUPLEX, 100Mbps
Got stored Credentials. Timeout 120s for Config Portal
LittleFS Flag read = 0xD0D04321
No doubleResetDetected
Saving config file...
Saving config file OK
After waiting 0.00 secs more in setup(), connection result is connected. Local IP: 192.168.2.232
HTTP server started @ 192.168.2.232
===============================================================
Open http://192.168.2.232/edit to see the file browser
Using username = admin and password = admin
===============================================================
[EM] freeing allocated params!
HStop doubleResetDetecting
Saving config file...
Saving config file OK
HHHHH HHHHHHHHHH HHHHHHHHHH HHHHHHHHHH

Debug

Debug is enabled by default on Serial. To disable, add before startConfigPortal()

AsyncESP32_Ethernet_manager.setDebugOutput(false);

You can also change the debugging level from 0 to 4

// Use from 0 to 4. Higher number, more debugging messages and memory usage.
#define _ESPASYNC_ETH_MGR_LOGLEVEL_    3

Troubleshooting

If you get compilation errors, more often than not, you may need to install a newer version of the ESP32 core for Arduino.

Sometimes, the library will only work if you update the ESP32 core to the latest version because I am using some newly added function.

If you connect to the created configuration Access Point but the ConfigPortal does not show up, just open a browser and type in the IP of the web portal, by default 192.168.4.1.