How Morse Code Constraints Reshaped One Developer's Approach to Accessible UI Design

A developer building a Morse code translator received feedback from users relying on assistive switch devices, where the only available input is a single short or long press. This binary input constraint mirrors Morse code's original two-symbol design, making the 1830s encoding a surprisingly natural fit for severely limited modern input hardware. The developer found that timing thresholds — distinguishing a dot from a dash — effectively become the entire interface, and that fixed global thresholds fail users with inconsistent motor control. To address this, an adaptive calibration approach was implemented, adjusting thresholds based on each user's own initial inputs rather than a universal standard. The experience broadened the developer's thinking about input design, highlighting that optimizing for fluency and forgiving signal interpretation matters most when an interface must serve users with constrained physical input.