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-- Copyright (C) 2002 Morgan Kaufmann Publishers, Inc
-- This file is part of VESTs (Vhdl tESTs).
-- VESTs is free software; you can redistribute it and/or modify it
-- under the terms of the GNU General Public License as published by the
-- Free Software Foundation; either version 2 of the License, or (at
-- your option) any later version.
-- VESTs is distributed in the hope that it will be useful, but WITHOUT
-- ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
-- FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
-- for more details.
-- You should have received a copy of the GNU General Public License
-- along with VESTs; if not, write to the Free Software Foundation,
-- Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
library ieee_proposed; use ieee_proposed.electrical_systems.all;
entity bit_to_analog is
port ( d : in bit;
terminal a : electrical );
end entity bit_to_analog;
----------------------------------------------------------------
architecture ideal of bit_to_analog is
constant v_low : real := 0.0;
constant v_high : real := 5.0;
signal v_in : real := 0.0;
quantity v_out across i_out through a to electrical_ref;
begin
v_in <= v_high when d = '1' else v_low;
v_out == v_in'ramp(1.0e-9);
end architecture ideal;
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