README

dept-of-scrapyard-robotics/gpio — GPIO module for the ScrapyardIO Framework.

Provides an object-oriented PHP interface to Linux GPIO character devices (/dev/gpiochip*) via the ext-gpio PHP extension. Supports configuring lines as inputs or outputs, setting line bias, and listening for rising/falling edge events.

Requirements

• PHP ^8.3
• ext-gpio 0.1.0 (Zephir extension — see DeptOfScrapyardRobotics/GPIO for build & install instructions)
• dept-of-scrapyard-robotics/fd 0.3.0
• Linux with GPIO char device support (/dev/gpiochip0 or similar)

Installation

composer require dept-of-scrapyard-robotics/gpio

Quick Start

Output — driving a pin high or low

use ScrapyardIO\GPIO\GPIO;
use ScrapyardIO\GPIO\Exceptions\GPIOException;

try {
    $gpio = (new GPIO())->usePin(6)->asOutput('my-app');
    $gpio->high(); // drive pin 6 high
    $gpio->low();  // drive pin 6 low
} catch (GPIOException $e) {
    echo $e->getMessage();
}

Input — reading a button with edge events

use ScrapyardIO\GPIO\GPIO;
use ScrapyardIO\GPIO\Enums\GPIOLineEvent;
use ScrapyardIO\GPIO\Exceptions\GPIOException;

try {
    $gpio = (new GPIO())->usePin(18)
        ->asInput('my-app')
        ->hasEvent(GPIOLineEvent::EDGE_FALLING)
        ->hasEvent(GPIOLineEvent::EDGE_RISING)
        ->build();

    fwrite(STDOUT, "Trigger your button.\n\n");
    var_dump($gpio->listen());
} catch (GPIOException $e) {
    echo $e->getMessage();
}

API Reference

GPIO

The entry point. Opens a GPIO chip device node.

new GPIO(string $chip = '/dev/gpiochip0')

Throws GPIOException if the requested line is already in use or unavailable.

GPIOConnectionBuilder

Fluent builder returned by GPIO::usePin(). Configure the line before finalizing it.

GPIOInput

Returned by ->asInput(...)->build().

GPIOOutput

Returned by ->asOutput(...) or ->build() when configured as output.

Enums

GPIOLineBias

Controls the electrical bias applied to an input line.

GPIOLineEvent

Edge types for event subscriptions on inputs.

Exceptions

All exceptions are of type ScrapyardIO\GPIO\Exceptions\GPIOException.

Examples

See the examples/ directory:

• gpio-button-example.php — reading a button via edge events on pin 18
• gpio-fan-example.php — driving an output (fan/trigger) on pin 6

License

MIT — © Angel Gonzalez / Project Saturn Studios