Wemos D1 Mini and TSOP4838

[MsbS]

I wanted to build a IR receiver based on D1 Mini and TSOP4838. I used the D1 previously for temperature monitoring (connecting a BME280 and a 2x16 display), so I know it generally works.

Anyway - the readings on GPIO pin of the IR receiver are changing every second. I found a thread suggesting to add a low-pass filter.

HOWEVER

the IR value is changing even if I set the GPIO number to an 'empty' pin where nothing is connected. Shouldn't it just read a constant 0?

EDIT/CORRECTION: changed the GPIO to 'empty' pin and after reboot, it keeps reading a constant value now (2893949928) - nothing changing in Log, IR reading constant value after refresh too. So, low-pass filter is needed probably...

[MsbS]

So, I found the solution to my problem. Nothing to do with broken GPIO, broken TSOP4838.

Probably obvious to most of you guys, but new information for me

DON"T use GPIO-2 (D4 on my D1 mini) for sensors, at least not for the IR receiver. As this is the GPIO address of the built-in LED, you will get a mess of readings. When I conected the IR receiver to a different GPIO, it all started working fine.