Arduino NodeMcu (ESP8266) Pin Mapping
If you use NodeMcu borad with Arduino IDE the following chart will help to find the pin maping
eg. NodeMCU Pin D1 is equivalent to arduino Pin 5.
Built in LED of NodeMCU is connected to D4 in arduino programming it equivalent to Pin 2
D0 = 16 D1 = 5 D2 = 4 D3 = 0 D4 = 2 D5 = 14 D6 = 12 D7 = 13 D8 = 15 D9 = 3 D10 = 1