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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_03.vhd,v 1.3 2001-10-26 16:29:33 paw Exp $
-- $Revision: 1.3 $
--
-- ---------------------------------------------------------------------
entity ch_03_03 is
end entity ch_03_03;
architecture test of ch_03_03 is
begin
process_3_1_c : process is
type mode_type is (immediate, other_mode);
type opcode_type is (load, add, subtract, other_opcode);
variable mode : mode_type;
variable opcode : opcode_type;
constant immed_operand : integer := 1;
constant memory_operand : integer := 2;
constant address_operand : integer := 3;
variable operand : integer;
procedure procedure_3_1_c is
begin
-- code from book:
if mode = immediate then
operand := immed_operand;
elsif opcode = load or opcode = add or opcode = subtract then
operand := memory_operand;
else
operand := address_operand;
end if;
-- end of code from book
end procedure_3_1_c;
begin
mode := immediate;
procedure_3_1_c;
mode := other_mode;
opcode := load;
procedure_3_1_c;
opcode := add;
procedure_3_1_c;
opcode := subtract;
procedure_3_1_c;
opcode := other_opcode;
procedure_3_1_c;
wait;
end process process_3_1_c;
end architecture test;
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