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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_03_ch_03_06.vhd,v 1.3 2001-10-26 16:29:33 paw Exp $
-- $Revision: 1.3 $
--
-- ---------------------------------------------------------------------
entity ch_03_06 is
end entity ch_03_06;
architecture test of ch_03_06 is
-- code from book:
type alu_func is (pass1, pass2, add, subtract);
-- end of code from book
signal func : alu_func := pass1;
signal operand1 : integer := 10;
signal operand2 : integer := 3;
begin
process_03_2_a : process (func, operand1, operand2) is
variable result : integer := 0;
begin
-- code from book:
case func is
when pass1 =>
result := operand1;
when pass2 =>
result := operand2;
when add =>
result := operand1 + operand2;
when subtract =>
result := operand1 - operand2;
end case;
-- end of code from book
end process process_03_2_a;
stimulus : process is
begin
func <= pass2 after 10 ns,
add after 20 ns,
subtract after 30 ns;
wait;
end process stimulus;
end architecture test;
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