Blynk WiFiManager for ESP8266/ESP32 (including ESP32-S2, ESP32-C3) with Multi-WiFi and Multi-Blynk. Fix SSL issue for Blynk Cloud Server now


Thanks for your encouraging words.

There are several ESP8266 AT-command libraries developed with similar functionalities such as:

  1. Blynk_Esp8266AT_WM
  1. ESP_AT_WiFiManager
  1. ESP_AT_WM_Lite
  1. ESP8266_AT_WebServer

You’re very welcome to use and give feedbacks, enhancement requests, bug reports, etc.


1 Like

Thanks for this clear overview!
For an Arduino Mega + ESP8266 shield libray to use for dynamic WifiManager functionality is ESP_AT_WM_Lite. Light means fewer parameters to configure? Ex. SSID and PW is fixed to the ugly ESP_AT_**** MyESP_AT_***?


It’s good that you start exploring the libs.

  1. Lite (light-weight) here means you don’t need a complicated WiFiManager with callback functions and a lot of memory which is impossible to use on those resource-constraint boards such as Mega.

Depending on how much memory you can spare, you can turn ON or OFF the dynamic params by using


  1. Ex. SSID and PW is fixed to the ugly ESP_AT_**** MyESP_AT_***?

The SSID and PW for Config Portal are configurable by using the function

void setConfigPortal(String ssid = "", String pass = "")

For example, in README

In Configuration Portal Mode, it starts an AP called ESP_AT_XXXXXX. Connect to it using the configurable password you can define in the code. For example, MyESP_AT_XXXXXX (see examples):

// SSID and PW for Config Portal
String ssid = "Your-Config-Portal-SSID";
String password = "Your-Config-Portal-SSID-PW";

And use the function in setup()

void setup()
// Debug console
while (!Serial);


Serial.print(F("\nStart Mega_ESP8266Shield on "));

// initialize serial for ESP module

ESP_AT_WiFiManager = new ESP_AT_WiFiManager_Lite(&EspSerial, ESP8266_BAUD);

// Optional to change default AP IP( and channel(10)
//ESP_AT_WiFiManager->setConfigPortalIP(IPAddress(192, 168, 120, 1));

// To configure Config Portal SSID and PW
ESP_AT_WiFiManager->setConfigPortal(ssid, password);



Works perfectly … Great work on the lib!

We are currently converting our project from wired to wifi functionality and further link it to blynk (and removing node-red dependency).
FYI: We noticed your lib has a EEPROM.h lib dependency what can be a challenge for projects using the much more functional EEPROMex.h lib as if you include both libs in your project there will be a conflict because the simple one defines “static EEPROMClass EEPROM” and the extended lib defines “external EEPROMClassEx EEPROM” so the compiler sees 2 classes with the same EEPROM name.
(Ugly) solution is to rename one of them in the lib and code will compile fine with both libraries used.


The easiest solution, if you insist of using the EEPROMex library, is to change the file

Esp8266_AT_WM_Lite.h of Esp8266_AT_WM_Lite library , assuming you’re using Mega, from

#include <EEPROM.h>


#include <EEPROMex.h>

Just recheck / retest the code to see if changing the lib breaking anything.

Also remember that some EEPROM locations have been reserved for the WM + dynamicParams purposes and use different location to store your params.

I also suggest to move this discussion to the correct topic from now on

BTW, I’ll add in next release v1.0.3

  1. Option to use EEPROMex library, by just specifying from sketch,
  2. Add support to nRF52-based boards, , such as Adafruit’s NRF52840_FEATHER, NRF52832_FEATHER, NRF52840_FEATHER_SENSE, NRF52840_ITSYBITSY, NRF52840_CIRCUITPLAY, NRF52840_CLUE, NRF52840_METRO, NRF52840_PCA10056, PARTICLE_XENON, NINA_B302_ublox, etc. The Credentials and Dynamic Parameters’ data will be stored in LittleFS/InternalFS .

Anything you’d like to suggest to add into that new release?

Sounds great. Think your library is already very complete. We noted using some of the setConfigPortal call some weird behavior on iPhones with WEP2 and security but we are still debugging to see what is causing it, apart from that great library.

Update June 25th 2020

Releases v1.0.16

  1. Fix bug and logic of USE_DEFAULT_CONFIG_DATA.
  2. Auto format SPIFFS / LittleFS for first time usage.

Dear @khoih. Congratulations on your work, it has helped me a lot. I would like to know how to prevent a failure / oscillation in the power supply causing the DoubleResetDetector to be involuntarily triggered? I have faced this problem and I do not know how to solve it. My devices after 2 consecutive power outages they enter the Config Portal, that is, the devices understand this power failure as triggering the DoubleResetDetector and do not leave the Config Portal until the information is filled, this is not good because the devices will be disconnected from the server while in the Config Portal in an undesired manner. is this possible to fix? thanks

It’s nice to know the library can somehow help you.

The power failure issue can be hopefully solved by

  1. Using battery
  2. Using big electrolytic capacitor
  3. Using UPS (Uninterrupted Power Supply)
  4. You can also try to shorten the DRD time (default at 10s to something like 1s). But not sure can totally solve your power failure issue.
// Number of seconds after reset during which a
// subsequent reset will be considered a double reset.
#define DRD_TIMEOUT 10
  1. You can also use the SW, instead of DRD, to force the Config Portal.
    Compare the examples ConfigOnSwitch and ConfigOnDoubleReset and see how to change.

Good Luck,

It sounds like there should be a timeout added to the double reset config so that it will not hangup for too long.

The DRD is a different and independent library and you certainly can configure its features to whatever way you’d like.

For example, in the ConfigOnDoubleReset example, the time spent in Config Portal (CP) is forced to be indefinite by disable time-out, as this is considered as intentional to do some change to the Credentials. So the CP will stay until valid / new data are entered and saved.

Have a look at ConfigOnDoubleReset.ino Line 666-673 for a way to change the time-out

1. No timeout

  if (drd->detectDoubleReset())
    // DRD, disable timeout.

    Serial.println("Open Config Portal without Timeout: Double Reset Detected");
    initialConfig = true;

2. Timeout

If you don’t like to disable time-out, just specify the time-out different from 0.

  if (drd->detectDoubleReset())
    // DRD, using timeout 180s

    Serial.println("Open Config Portal with 180s Timeout: Double Reset Detected");
    initialConfig = true;

Looks like a reasonable way to handle the problem.

Updated Jan 1st 2021

Major Releases v1.1.0

  1. Add support to LittleFS for ESP32 using LittleFS_esp32 Library
  2. Add support to MultiDetectDetector. MultiDetectDetector feature to force Config Portal when configurable multi-reset is detected within predetermined time.
  3. Clean-up all compiler warnings possible.
  4. Add Table of Contents
  5. Add Version String
  6. Add MRD-related examples.

Bạn là người Việt Nam phải không?

Updated Feb 24th 2021

Major Releases v1.2.0

  1. Configurable Customs HTML Headers, including Customs Style, Customs Head Elements, CORS Header.
  2. Add support to ESP32-S2 (ESP32-S2 Saola and AI-Thinker ESP-12K). Currently using EEPROM only. To add support to LittleFS and SPIFFS in future releases.
  3. Fix Config Portal Bug.
  4. Tested with Latest ESP32 Core 1.0.5 for ESP32-based boards.
  5. Update examples

Releases v1.1.3

  1. To permit autoreset after configurable timeout if DRD/MRD or non-persistent forced-CP. Check Good new feature: Blynk.resetAndEnterConfigPortal() Thanks & question #27

Releases v1.1.2

  1. Fix rare Config Portal bug not updating Config and dynamic Params data successfully in very noisy or weak WiFi situation

Releases v1.1.1

  1. Add functions to control Config Portal from software or Virtual Switches. Check How to trigger a Config Portal from code #25
  2. Add examples to demo the new Virtual ConfigPortal SW feature
  3. Optimize code

Dear @khoih , congratulations on your work.
I realized that when the wi-fi + internet access are working normally and there is a failure in both due to a power outage or other similar problem that leaves them off for a time greater than or equal to 15 minutes and when they are turned on (wifi + access to internet working) esp8266 reconnects to wifi but cannot connect to the blynk-cloud server. Could you tell me why this is happening? thanks.

Sorry I have no idea what’s happening there as it doesn’t make sense at all.

What if you turn OFF power to the board more than 15 mins then turn back ON?

It’s possibly something wrong in your program and/or your network settings and only you can find out why. I’m afraid I can’t help you anything.

Good Luck,

15 minutes sounds like the amount of time that the router will hold a routing table entry for a device after it disappears off the network, but why that would prevent it re-connecting to the router later is a mystery to me.

I’d start by turning everything off then on again :grinning:


2 posts were split to a new topic: Buttons not working when internet disconnected