WeMos D1 mini 433mhz receiver - use D8 for DATA

It took me hours to figure out why my WeMos D1 mini + 433mhz receiver work normally when connected to a PC/Arduino IDE, but doesn't work when powered through a power bank or power pins.

Problem was that only D8 pin is pulled down on WeMos, others are not. Connecting DATA to D3 resulted in voltage not reaching 0 when it should have. D0 doesn't support interrupts at all, so RCSwitch wouldn't work.

Alternatively, manual pull down (connecting to group through a high-value resistor) on DATA line should also work.

Here's the basic code example, use "15" for D8 pin value.

P.S.: right GND marking (near antenna) on that 433mhz receiver is incorrect, it's likely to fry your Arduino if you actually connect it. Just don't connect it to anything.