Skip to main content

GPIO (General Purpose Input/Output)

LibXR::GPIO provides a cross-platform abstract interface for general purpose input/output (GPIO), supporting multiple input/output modes and interrupt callback mechanisms. Users can inherit this interface to implement platform-specific GPIO control logic.

Interface Overview​

Configuration Enums​

enum class Direction : uint8_t {
  INPUT,                 // Input mode
  OUTPUT_PUSH_PULL,      // Push-pull output
  OUTPUT_OPEN_DRAIN,     // Open-drain output
  FALL_INTERRUPT,        // Falling edge interrupt
  RISING_INTERRUPT,      // Rising edge interrupt
  FALL_RISING_INTERRUPT  // Both-edge interrupt
};

enum class Pull : uint8_t {
  NONE,  // No pull
  UP,    // Pull-up
  DOWN   // Pull-down
};

Configuration Structure​

struct Configuration {
  Direction direction;  // Pin direction
  Pull pull;            // Pull configuration
};

Callback Type​

using Callback = LibXR::Callback<>;

Construction and Configuration​

GPIO();  // Default constructor
virtual ErrorCode SetConfig(Configuration config) = 0;

Pin Control​

virtual bool Read() = 0;              // Read pin level
virtual ErrorCode Write(bool value) = 0; // Write pin level

Interrupt Control​

virtual ErrorCode EnableInterrupt() = 0;   // Enable interrupt
virtual ErrorCode DisableInterrupt() = 0;  // Disable interrupt

Register Event Callback​

using Callback = LibXR::Callback<>;
ErrorCode RegisterCallback(Callback callback); // Register interrupt handler

Feature Summary​

  • Supports multiple configuration modes: input, output, interrupt;
  • Provides a type-safe configuration structure;
  • Event handling uses a unified callback interface, callable in ISR or task context;
  • Platform implementations must fully define all virtual functions;
  • Can be integrated with other LibXR modules such as Topic, Timer, etc.