GPIOUtils

GPIOUtils is a lightweight, composable toolkit for writing clean, non-blocking Arduino code.

It solves the small but persistent problems that make embedded code messy:

• switch bounce
• noisy analog signals
• timing logic scattered everywhere
• awkward state machines
• one-off hacks that don’t scale

Instead of monolithic frameworks, GPIOUtils gives you small building blocks that snap together cleanly.

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🚀 What this library actually lets you do

With a few simple components, you can build behaviour like:

• A button with debounce + long-press + auto-repeat
• An analog input with noise suppression + hysteresis
• A clean event pipeline like:

button → debounce → edge → long-press → one-shot → timed output

• Non-blocking timing like:
  • periodic tasks
  • pulse generation
  • delayed triggers
  • rate-limited signals

All without delay() and without tangled logic.

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🧩 Design philosophy

GPIOUtils follows a few strict rules:

1. No hidden side effects

Constructors never touch hardware.
All setup happens explicitly in:

begin();

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2. Clear ownership of pins

• If a class owns a pin → it configures it
• If it doesn’t → it never touches hardware

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3. Composition over complexity

Instead of giant helper classes, everything is designed to chain:

raw input → conditioning → event → timing → output

You build exactly what you need—nothing more.

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📦 Components overview

🔹 Analog conditioning

• AnalogCalibrator
  Fix real-world ADC range issues (inputs that don’t hit full scale)

• Dejitter
  Removes small analog noise (deadband filtering)

• Schmitt
  Converts noisy analog signals into stable digital states (hysteresis)

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🔹 Digital input cleanup

• Debounce
  Clean up mechanical switches

• EdgeDetector
  Detect rising/falling edges cleanly

• GlitchFilter
  Reject short spikes and false triggers

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🔹 Event & timing logic (no GPIO required)

• OneShotEvent
  Fire a fixed-duration event (optionally delayed)

• PulseGenerator
  Generate pulse trains (finite or continuous)

• AutoRepeat
  Keyboard-style repeating input

• MultiPress
  Detect double/triple clicks

• LongPressDetector
  Detect press-and-hold actions

• Toggle
  Convert events into persistent state

• RateLimiter
  Smooth or constrain value changes

• PeriodicTimer
  Generate regular ticks without blocking

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🔹 Output control

• TimedOutput (owns a pin)
  Drive outputs with:
  • timed pulses
  • scheduled transitions
  • non-blocking control

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🔹 Utility helpers

• adcToU8() → ADC → 8-bit
• adcToFloat() → normalized
• adcToFloat(min, max) → scaled range

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🧠 Example: clean, readable logic

Instead of tangled code:

if (buttonPressed && !lastState && millis() - lastTime > 50) { ... }

You get:

Debounce button(2);
EdgeDetector edge;
OneShotEvent pulse(1000);

void loop() {
    bool clean = button.update();
    if (edge.rising(clean)) {
        pulse.trigger();
    }

    if (pulse.update()) {
        digitalWrite(LED_PIN, HIGH);
    } else {
        digitalWrite(LED_PIN, LOW);
    }

    // Do something else (nonblocking) ...
}

Readable. Testable. Composable.

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📁 Structure

GPIOUtils/
  src/
    GPIOUtils.h
    impl/
  examples/

Only include:

#include <GPIOUtils.h>

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📘 Examples

Start here:
👉 examples/README.md

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🎯 Why use GPIOUtils?

• No blocking (delay()-free)
• No frameworks or magic
• Small, focused components
• Easy to reason about
• Works on any Arduino-compatible board

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⚙️ Philosophy in one sentence

“Do one thing well, and compose everything else.”