A camera shutter button is a familiar example of two related actions living under one finger. This breakout brings that half-press/full-press interaction to a project without needing two separate buttons.

The ALPS SKQAACE010 switch connects P1 and P2 at the first stage. Pressing further connects P1, P2 and P3, giving the controller a second state to detect.

That could mean preview then confirm, or take a reading then store it. The button supplies the two physical stages; the host firmware defines their meaning and handles switch debouncing.

Key specifications:

• ALPS SKQAACE010

• First stage connects P1/P2

• Second stage connects P1/P2/P3

Product documentation: https://www.questwiseventures.com/products/2-stage-double-action-tactile-button-switch