Rotary with Espruino Pico

When using the switch you need pin 5 of the rotary too.

Rotary → Pico
5 → 3.3V
3 → B5 (or any other input pin)

As @ClearMemory041063 mentioned above it is easy to watch a pin:

// some untested code
pinMode(B5, "input_pulldown");

setWatch( function( event ) {
    console.log( event.state ? "Button released" : "Button pressed")
}, B5, { repeat: true, debounce: 50 });