Why Not Just Use Arduino Functions?
The Arduino ecosystem provides convenient functions like digitalWrite(), pinMode(), and digitalRead() that simplify hardware interaction. However, these functions introduce significant overhead due to internal checks and abstraction layers. This overhead, while negligible for general applications, becomes a limiting factor for performance-critical tasks such as high-frequency signal generation or precise timing control.

Let’s compare the two approaches:

Feature // Arduino Functions // Fast Digital Pin Macros

Ease of Use // High (Abstracted API) // Low (Direct Register Access)

Performance // Moderate (50+ Clock Cycles) // High (1–2 Clock Cycles)

Portability // High (Across MCU Variants) // Low (AVR-Specific)

Timing Critical Apps // Not Ideal // Ideal

Abstraction // High (User-Friendly) // Low (Bare-Metal Control)