Issue with Blynk Example "Simple push notification example"


I’m trying to use the “Simple push notification example” from the Blynk Example Code Generator with an ESP32 and Arudino IDE, but I simply don’t get it to run.

I’m quite new to the topic in general and I guess it’s actually not a Blynk-specific issue, but since it’s concerning the Blynk Example code, maybe someone else already ran into this problem.
And I just have no idea how to continue otherwise or debug this, since I’m still a little noob :slight_smile:

In the meantime, I modified the code a bit by setting a variable for the Button Pin and changed the Pin to 23, since the GPIO2 seems to not work properly on my board, but I also checked it by using the default example.

I tried several other pins, adding delays, changing the interrupt method and some other things, but as soon as the button is pressed (or actually: button pin connected to GND), it simply breaks.
Sometimes it restarts afterwards automatically and other times it doesn’t.

Serial Monitor output:

[25] Connecting to xxx
[635] Connected to WiFi
[635] IP: xx.xx.xx.xx
    ___  __          __
   / _ )/ /_ _____  / /__
  / _  / / // / _ \/  '_/
 /____/_/\_, /_//_/_/\_\
        /___/ v0.6.1 on ESP32

[707] Connecting to
[874] Ready (ping: 40ms).
Button is pressed.
Guru Meditation Error: Core  1 panic'ed (Interrupt wdt timeout on CPU1)
Core 1 register dump:
PC      : 0x4008c18a  PS      : 0x00060534  A0      : 0x8008b3a3  A1      : 0x3ffbfb30  
A2      : 0x3ffcb880  A3      : 0x3ffbc77c  A4      : 0x00000001  A5      : 0x00000001  
A6      : 0x00060523  A7      : 0x00000000  A8      : 0x3ffbc77c  A9      : 0x3ffbc77c  
A10     : 0x00000019  A11     : 0x00000019  A12     : 0x00000001  A13     : 0x00000001  
A14     : 0x00060521  A15     : 0x00000000  SAR     : 0x0000000a  EXCCAUSE: 0x00000006  
EXCVADDR: 0x00000000  LBEG    : 0x4000c2e0  LEND    : 0x4000c2f6  LCOUNT  : 0xffffffff  
Core 1 was running in ISR context:
EPC1    : 0x4012ad53  EPC2    : 0x00000000  EPC3    : 0x00000000  EPC4    : 0x4008c18a

ELF file SHA256: 0000000000000000

Backtrace: 0x4008c18a:0x3ffbfb30 0x4008b3a0:0x3ffbfb50 0x400896d7:0x3ffbfb70 0x4012acd1:0x3ffbfbb0 0x4011845b:0x3ffbfbd0 0x40117cd9:0x3ffbfc00 0x40118209:0x3ffbf


/* Comment this out to disable prints and save space */
#define BLYNK_PRINT Serial

#include <WiFi.h>
#include <WiFiClient.h>
#include <BlynkSimpleEsp32.h>

// You should get Auth Token in the Blynk App.
// Go to the Project Settings (nut icon).
char auth[] = "xxx";

// Your WiFi credentials.
// Set password to "" for open networks.
char ssid[] = "xxx";
char pass[] = "xxx";
int buttonPin = 23;

void notifyOnButtonPress()
  // Invert state, since button is "Active LOW"
  int isButtonPressed = !digitalRead(buttonPin);
  if (isButtonPressed) {
    Serial.println("Button is pressed.");

    // Note:
    //   We allow 1 notification per 5 seconds for now.
    Blynk.notify("Yaaay... button is pressed!");

    // You can also use {DEVICE_NAME} placeholder for device name,
    // that will be replaced by your device name on the server side.
    //Blynk.notify("Yaaay... {DEVICE_NAME}  button is pressed!");

void setup()
  // Debug console

  Blynk.begin(auth, ssid, pass);
  // You can also specify server:
  //Blynk.begin(auth, ssid, pass, "", 80);
  //Blynk.begin(auth, ssid, pass, IPAddress(192,168,1,100), 8080);

  // Setup notification button on buttonPin
  pinMode(buttonPin, INPUT_PULLUP);
  // Attach pin buttonPin interrupt to our handler
  attachInterrupt(digitalPinToInterrupt(buttonPin), notifyOnButtonPress, CHANGE);

void loop()

Any help is appreciated!


Yes, there seems to be a problem when trying to send notifications with the ESP32. I initially suspected it was an interrupt issue, but commenting-out the Blynk.notify command prevents the ESP crashing.

@vshymanskyy, @Dmitriy is this something you are aware of?


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