-- Abstract PWM output interface definitions

-- Copyright (C)2016-2023, 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:
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-- * Redistributions of source code must retain the above copyright notice,
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-- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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WITH Ada.Text_IO;
WITH IO_Interfaces;

PACKAGE PWM IS

  PWM_Error : EXCEPTION;

  TYPE DutyCycle IS NEW Float RANGE 0.0 .. 100.0;

  MinimumDutyCycle : CONSTANT DutyCycle := DutyCycle'First;
  MaximumDutyCycle : CONSTANT DutyCycle := DutyCycle'Last;

  -- Instantiate text I/O packages

  PACKAGE DutyCycle_IO IS NEW Ada.Text_IO.Float_IO(DutyCycle);

  PACKAGE Duration_IO IS NEW Ada.Text_IO.Fixed_IO(Duration);

  -- Instantiate abstract interfaces packages

  PACKAGE DutyCycleInterfaces IS NEW IO_Interfaces(DutyCycle);

  PACKAGE DurationInterfaces IS NEW IO_Interfaces(Duration);

  -- Define an abstract interface for GPIO pins, derived from both
  -- DutyCycleInterfacesInterfaces.OutputInterface and
  -- DurationInterfaces.OutputInterface

  TYPE OutputInterface IS INTERFACE AND
    DutyCycleInterfaces.OutputInterface AND
    DurationInterfaces.OutputInterface;

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

  TYPE Output IS ACCESS ALL OutputInterface'Class;

  -- Additional methods

  FUNCTION GetPeriod(Self : IN OUT OutputInterface)
    RETURN Duration IS ABSTRACT;

END PWM;