Thanks for porting Espruino to the RuuviTag! I was looking forward to doing it myself but this works for me to :-).
However, it looks like the LEDs and BTN are low-active:
- LED1.write(false); // => LED is on
- LED1.write(true); // => LED is off
- digitalRead(BTN); =0 //if B is pressed
Not a big issue, can it be fixed?