Esp8266 crash, exception and restart when write blynk property

Need Help With My Project
1

Hi everyone.

The following method cause my esp8266 exception error and reboot when i press the button vpin 100
if i uncomment the line Blynk.virtualWrite(V73, 1023) or Blynk.virtualWrite(V73, 0);
v73 is a led on blynbk app. D8 high will close an external relay to start the fan. I really dont know why this happen. Any suggestion for this? Thanks

BLYNK_WRITE(V100) {
  int pinValue = param.asInt();
  if (pinValue == 1)
  {
 
    digitalWrite(D8, HIGH);

   // Blynk.virtualWrite(V73, 1023); 
  }
  else
  {
 
    digitalWrite(D8, LOW);
 
  //  Blynk.virtualWrite(V73, 0);
  }
}
2

Hi,

You don’t need to Blynk.virtualwrite() to the Blynk LED Widget. Have a look at the LED Widget example sketch to see how you use it.

https://examples.blynk.cc/?board=ESP8266&shield=ESP8266%20WiFi&example=Widgets%2FLED%2FLED_Blink

You declare the widget:

WidgetLED led1(V1);

Then simply turn it On or Off:

led1.off();
led1.on();

Use the eamples

cul
billd

1 Like
3

The LED widget has 256 brightness levels (0-255) so Blynk.virtualWrite(V73, 255); is what you’d normally use to turn an LED widget on to maximum brightness if you are using the virtualWrite approach as opposed to the led1.on() approach described by Bill.

Pete.

1 Like
4

Thank you Bill and Pete

your helps solve my problems

Regards

1 Like
5 
WidgetLED fanled(V23);
 WidgetLED lcdled(V21);

 BLYNK_WRITE(V100) {
 int pinValue = param.asInt();
 if (pinValue == 1)
 {
 digitalWrite(D8, HIGH);
fanled.on();// system crash  , exception after 1 or 2 times button pressed

 }
 else
 {
 digitalWrite(D8, LOW);

fanled.off();  //system crash  , exception after 1 or 2 times button pressed
 }

but if i place this line fanled.on(); or fanled.off(); inside loop , it works without any problem.

this code is inside loop()

 if (digitalRead(D8) == HIGH)
{
 Blynk.virtualWrite(V100, 1);//toggle the button
 fanled.on();
}
else
{
    Blynk.virtualWrite(V100, 0);//toggle the button
    fanled.off();
}
6

@Anthony_Chen please edit your post and use triple backticks at the beginning and end of your code, and remove the ‘>’ characters at the beginning of each line of code.
Triple backticks look like this:
```

Pete.

1 Like
7

What exactly is the exception error that you get when the crash occurs?
Have you tried decoding it with the exception decoder?

Pete.