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-- Copyright (C) 1996 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
-- ---------------------------------------------------------------------
--
-- $Id: ch_16_ch_16_05.vhd,v 1.1.1.1 2001-08-22 18:20:48 paw Exp $
-- $Revision: 1.1.1.1 $
--
-- ---------------------------------------------------------------------
entity ch_16_05 is
end entity ch_16_05;
----------------------------------------------------------------
architecture test of ch_16_05 is
subtype word is bit_vector(0 to 31);
type word_array is array (integer range <>) of word;
function resolve_words ( words : word_array ) return word is
begin
if words'length > 0 then
return words(words'left);
else
return X"00000000";
end if;
end function resolve_words;
subtype resolved_word is resolve_words word;
-- code from book:
signal source_bus_1, source_bus_2 : resolved_word bus;
signal address_bus : resolved_word bus;
disconnect all : resolved_word after 2 ns;
-- end of code from book
signal s : word;
signal g : boolean;
begin
b : block (g) is
begin
source_bus_1 <= guarded s after 4 ns;
source_bus_2 <= guarded s after 4 ns;
address_bus <= guarded s after 4 ns;
end block b;
stimulus : process is
begin
s <= X"DDDDDDDD";
wait for 10 ns;
g <= true;
wait for 10 ns;
s <= X"AAAAAAAA";
wait for 10 ns;
g <= false;
wait for 10 ns;
s <= X"11111111";
wait;
end process stimulus;
end architecture test;
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