-- --------------------------------------------------------------------------
--
-- Title      : Draft Standard VHDL 1076.1.1 Packages for Multiple Energy 
--            : Domain Support.
--
-- Library    : This package shall be compiled into a library symbolically
--            : named IEEE.
--
-- Developers : IEEE 1076.1.1 Working Group
--
-- Purpose    : This package contains declarations for modeling in the
--            : electrical energy domain.
--
-- Note       :
--
-- --------------------------------------------------------------------------
--   Modification History :
--
--   Version   Date           Description
--     1.0     6 July 2001    Original version.
--     1.1     4 March 2002   FDL 2001 & BMAS 2001 revisions
--     1.2     31 Aug 2002    DAC 2002 revisions
--     1.3     30 Sep 2002    FDL 2002 revisions
-- --------------------------------------------------------------------------

library IEEE;
    use IEEE.FUNDAMENTAL_CONSTANTS.all;

package ELECTRICAL_SYSTEMS is
   -- type declarations

   -- electrical domain
   -- subtype declarations
   subtype VOLTAGE     is REAL tolerance "DEFAULT_VOLTAGE";
   subtype CURRENT     is REAL tolerance "DEFAULT_CURRENT";
   subtype CHARGE      is REAL tolerance "DEFAULT_CHARGE";
   subtype RESISTANCE  is REAL tolerance "DEFAULT_RESISTANCE";
   subtype CAPACITANCE is REAL tolerance "DEFAULT_CAPACITANCE";
   subtype MMF         is REAL tolerance "DEFAULT_MMF";
   subtype FLUX        is REAL tolerance "DEFAULT_FLUX";
   subtype INDUCTANCE  is REAL tolerance "DEFAULT_INDUCTANCE";

   -- attribute declarations
   -- Use of UNIT to designate units 
   attribute UNIT of VOLTAGE       : subtype is "Volt";
   attribute UNIT of CURRENT       : subtype is "Ampere";
   attribute UNIT of CHARGE        : subtype is "Coulomb";
   attribute UNIT of RESISTANCE    : subtype is "Ohm";
   attribute UNIT of CAPACITANCE   : subtype is "Farad";
   -- use ampere-turns or just amperes?
   attribute UNIT of MMF           : subtype is "Ampere-turns";
   attribute UNIT of FLUX          : subtype is "Weber";
   attribute UNIT of INDUCTANCE    : subtype is "Henry";

   -- Use of SYMBOL to designate abbreviation of units
   attribute SYMBOL of VOLTAGE     : subtype is "V";
   attribute SYMBOL of CURRENT     : subtype is "A";
   attribute SYMBOL of CHARGE      : subtype is "C";
   attribute SYMBOL of RESISTANCE  : subtype is "Ohm";
   attribute SYMBOL of CAPACITANCE : subtype is "F";
   attribute SYMBOL of MMF         : subtype is "A-t";
   attribute SYMBOL of FLUX        : subtype is "W";
   attribute SYMBOL of INDUCTANCE  : subtype is "H";

   -- nature declarations
   nature ELECTRICAL is
      VOLTAGE        across
      CURRENT        through
      ELECTRICAL_REF reference;
   nature ELECTRICAL_VECTOR is array (NATURAL range <>) of ELECTRICAL;
   -- vector subtypes for array types?

   nature MAGNETIC is
      MMF          across
      FLUX         through
      MAGNETIC_REF reference;
   nature MAGNETIC_VECTOR is array (NATURAL range <>) of MAGNETIC;

   -- vector subtype declarations
   subtype VOLTAGE_VECTOR    is ELECTRICAL_VECTOR'across;
   subtype CURRENT_VECTOR    is ELECTRICAL_VECTOR'through;
   subtype CHARGE_VECTOR     is REAL_VECTOR      tolerance "DEFAULT_CHARGE";
   subtype RESISTANCE_VECTOR is REAL_VECTOR      tolerance "DEFAULT_RESISTANCE";
   subtype MMF_VECTOR        is MAGNETIC_VECTOR'across;
   subtype FLUX_VECTOR       is MAGNETIC_VECTOR'through;
   subtype INDUCTANCE_VECTOR is REAL_VECTOR      tolerance "DEFAULT_INDUCTANCE";

   -- attributes of vector subtypes
   -- Use of UNIT to designate units
   attribute UNIT of VOLTAGE_VECTOR       : subtype is "Volt";
   attribute UNIT of CURRENT_VECTOR       : subtype is "Ampere";
   attribute UNIT of CHARGE_VECTOR        : subtype is "Coulomb";
   attribute UNIT of RESISTANCE_VECTOR    : subtype is "Ohm";
   attribute UNIT of CAPACITANCE_VECTOR   : subtype is "Farad";
   -- use ampere-turns or just amperes?
   attribute UNIT of MMF_VECTOR           : subtype is "Ampere-turns";
   attribute UNIT of FLUX_VECTOR          : subtype is "Weber";
   attribute UNIT of INDUCTANCE_VECTOR    : subtype is "Henry";

   -- Use of SYMBOL to designate abbreviation of units
   attribute SYMBOL of VOLTAGE_VECTOR     : subtype is "V";
   attribute SYMBOL of CURRENT_VECTOR     : subtype is "A";
   attribute SYMBOL of CHARGE_VECTOR      : subtype is "C";
   attribute SYMBOL of RESISTANCE_VECTOR  : subtype is "Ohm";
   attribute SYMBOL of CAPACITANCE_VECTOR : subtype is "F";
   attribute SYMBOL of MMF_VECTOR         : subtype is "A-t";
   attribute SYMBOL of FLUX_VECTOR        : subtype is "W";
   attribute SYMBOL of INDUCTANCE_VECTOR  : subtype is "H";

   -- subnature declarations

   -- object declarations

   -- operation declarations (e.g., subprograms)

   -- alias declarations
   alias GROUND is ELECTRICAL_REF;
end package ELECTRICAL_SYSTEMS;