WiFi automatic reconnection not working in 2.4.0 but works in core 2.3.0

[jplavoiemtl]

Basic Infos

Hardware: ESP-12E
Core Version: 2.4.0

Description: bug found in esp8266 core 2.4.0

Here is a bug I found in esp core 2.4.0 that was not there in core 2.3.0. The esp does not reconnect automatically to WiFi while using WiFiManager. When my esp is running it connect to WiFi no problem. I have a WiFi status of 3 which is connected. Serial.println(WiFi.status());

Then I deactivate WiFi in my router to simulate a WiFi problem. After I reactivate WiFi on the router, the esp does not reconnect to WiFi. I check status at 1 second intervals and I get 6 for a WL_DISCONNECT

The problem is not related with WiFiManager. To solve it I had to revert back to esp core 2.3.0 and the WiFi reconnects fine and WiFiManager works like a charm.

Quick fix: revert to previous core 2.3.0

I hope it will be resolved in the next version. In the mean time, if someone experience the same problem with core 2.4.0, revert to core 2.3.0 as a quick fix.

Settings in IDE

Module: NodeMCU 1.0 (ESP-12E)
Flash Size: 4MB
CPU Frequency: 80Mhz
Flash Mode:

Sketch

Basic WiFiManager and very simple code to initialize WiFi in setup()

WiFiManager wifiManager;
wifiManager.setTimeout(180);    
wifiManager.autoConnect("NodeMcuM5");

Very little in the main loop checking WiFi which is the purpose of WiFiManager.

//If MQTT client is not connected and wifi is connected
if (!client.connected() && WiFi.status() == WL_CONNECTED) {
  reconnectMQTT();
 }

[tonton81]

have you tried the handler instead of polling? theres an event callback when ESP is connected and gets an IP, and another event callback when its disconnected. obviously you shouldnt call reconnectMQTT from the callback, but you can set a bool in the callback and when your loop() hits itll disable the bool after running reconnectMQTT

[jplavoiemtl]

@tonton81 The code here works well and going very fast through the main loop so there is no polling issue. The purpose of this bug report issue is for the WiFi handling in the esp core 2.4.0 that was working fine in previous version 2.3.0 in order to fix the current core release. WiFi is not reconnecting like it should in the newer release. But I note your disconnect handler use for a future project, thanks for the input.

[devyte]

@jplavoiemtl please erase all flash, and try with latest git.

[jplavoiemtl]

@devyte Ok I can give it a try. How can I erase all flash using a Windows computer? A good tutorial somewhere?

[tonton81]

i presume with esptool, igor suppost to add a new feature regarding that, to erase everything, or just some parts when flashing

[jplavoiemtl]

@tonton81 In the mean time of erasing flash, I'll try the latest git on a brand new Wemos D1 mini board with the latest git in Arduino IDE and report my findings shortly.

[devyte]

@jplavoiemtl erase flash with esptool-ck.

[jplavoiemtl]

@tonton81 Test done with a brand new Wemos board and Arduino IDE esp8266 core 2.4.0. Problem is still there, no WiFi re-connection after I interrupt WiFi on my router. I see WL_DISCONNECT value of 6 and the module is not getting back online with WiFi.

Installed core 2.3.0 and there is no re connection problem, it works fine with this older core. So this seems to confirm the bug. I used a brand new board instead of erasing flash because I'm not to familiar with erasing flash and lost a full day on this WiFi issue yesterday. I'm open to try erasing flash later today or tomorrow.

[jplavoiemtl]

@tonton81 Finally I did what you suggested and erased flash on module. I get the same problem or bug on esp core 2.4.0. Reverting to core 2.3.0 works fine.

[drschlaumeier]

Is it same as already reported?
#4257

[devyte]

@jplavoiemtl as I said, please try latest git, not release 2.4.0.

[jplavoiemtl]

@devyte trying to install the latest git. After restarting Arduino where do I go to see if I'm using this git? In boards manager for esp8266 I only see 2.3.0-rc2 and previous versions. How can I use the git?

Here are the steps I did:
Using git version

Linux build status

Install Arduino 1.8.2 from the Arduino website.
Go to Arduino directory
Clone this repository into hardware/esp8266com/esp8266 directory (or clone it elsewhere and create a symlink)

cd hardware
mkdir esp8266com
cd esp8266com
git clone https://github.com/esp8266/Arduino.git esp8266

Download binary tools (you need Python 2.7)

cd esp8266/tools
python get.py

Restart Arduino

Now what?

[devyte]

@jplavoiemtl you can ever have only one version of a package installed, and that holds for git. That means that, if you install git, you also have to uninstall whatever version you installed from the board manager. Then restart IDE, then rebuild/retest.
BTW, after this, you won't see git in the board manager.
If you want to make sure of the version you are building with, use ESP.getCoreVersion(), ESP.getSdkVersion() etc to print out to serial.

[jplavoiemtl]

@devyte Using ESP.getCoreVersion(), ESP.getSdkVersion() etc to print out to serial I get:

 Core: 00000000
 Sdk: 2.2.0(f28eaf2)

Does this makes sense for core?
My boards manager shows I have esp82666 by ESP8266 Community version 2.3.0 installed.
BTW, this version works fine with WiFi reconnection.

Then I erased flash, uninstalled core 2.3.0 from boards manager then rebuild/retest.
This version gives me the same core and sdk version and works well with WiFi.
So what version of core am I running since 00000000 doesn't really tell me?