-- Abstract GPIO pin interface definitions

-- Copyright (C)2026, Philip Munts dba Munts Technologies.
--
-- Redistribution and use in source and binary forms, with or without
-- modification, are permitted provided that the following conditions are met:
--
-- * Redistributions of source code must retain the above copyright notice,
--   this list of conditions and the following disclaimer.
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-- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
-- AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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-- LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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-- POSSIBILITY OF SUCH DAMAGE.

WITH IO_Interfaces;

PACKAGE GPIO IS

  -- Define an exception for GPIO errors

  Error : EXCEPTION;

  -- Type definitions

  TYPE Direction IS (Input, Output);

  -- Instantiate I/O interfaces package for boolean digital I/O pins

  PACKAGE Interfaces IS NEW IO_Interfaces(Boolean);

  -- Define an abstract interface for GPIO pins, derived from
  -- Interfaces.InputOutputInterface

  TYPE PinInterface IS INTERFACE AND Interfaces.InputOutputInterface;

  -- Define an access type compatible with any subclass implementing
  -- PinInterface

  TYPE Pin IS ACCESS ALL PinInterface'Class;

END GPIO;