Weird led blinking

[mark.jeronimus]

I have an ESP32 dev board wired up as a Domoticz sensor node. Apart from the WiFi library, it's 100% my own code. I don't control the onboard LED.

Lately I noticed the onboard LED is blinking in a specific pattern (long short short short short) even though my software is still running.

Does anyone have an idea what it might be?

[Sprite]

What board are you using? Any idea what 'the onboard LED' is connected to?

[mark.jeronimus]

Some Chinese knock-off ("HW-628 V1.1") of the NodeMCU v3.

The LED is wired to Arduino pin D2 / Board pin 4 / ESP pin 22. When I digitalwrite this pin I can control the LED.

[Sprite]

Hm, that pin doesn't do anything specific. No clue then, sorry.