-- Abstract servo output interface definitions

-- Copyright (C)2016-2023, Philip Munts dba Munts Technologies.
--
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-- 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 Servo IS

  Servo_Error : EXCEPTION;

  TYPE Position IS NEW Float RANGE -1.0 .. 1.0;

  MinimumPosition  : CONSTANT Position := Position'First;
  NeutralPosition  : CONSTANT Position := 0.0;
  MaximumPosition  : CONSTANT Position := Position'Last;

  -- Instantiate text I/O package

  PACKAGE Position_IO IS NEW Ada.Text_IO.Float_IO(Position);

  -- Instantiate abstract interfaces package

  PACKAGE Interfaces IS NEW IO_Interfaces(Position);

  -- Define an abstract interface for servo outputs, derived from
  -- Interfaces.OutputInterface

  TYPE OutputInterface IS INTERFACE AND Interfaces.OutputInterface;

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

  TYPE Output IS ACCESS ALL OutputInterface'Class;

END Servo;