Double-click

A button on GPIO27 (to ground), a green LED on GPIO17 and a red LED on GPIO22.

• a double click — a second press starting within 0.4 s of releasing the first — toggles the red LED
• a single click — no second press within 0.4 s — toggles the green LED

So a single click can only be decided once the 0.4 s have passed. Both LEDs start off.

The test clicks (0.1 s each) at 1.0 s; at 2.5 s and 2.75 s (a double); and at 4.0 s.