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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_07.vhd,v 1.3 2001-10-26 16:29:33 paw Exp $
-- $Revision: 1.3 $
--
-- ---------------------------------------------------------------------
entity ch_03_07 is
end entity ch_03_07;
architecture test of ch_03_07 is
begin
process_03_2_b : process is
-- code from book:
subtype index_mode is integer range 0 to 3;
variable instruction_register : integer range 0 to 2**16 - 1;
-- end of code from book
variable index_value : integer;
constant accumulator_A : integer := 1;
constant accumulator_B : integer := 2;
constant index_register : integer := 3;
begin
for i in index_mode loop
instruction_register := i * 2**12;
-- code from book:
case index_mode'((instruction_register / 2**12) rem 2**2) is
when 0 =>
index_value := 0;
when 1 =>
index_value := accumulator_A;
when 2 =>
index_value := accumulator_B;
when 3 =>
index_value := index_register;
end case;
-- end of code from book
end loop;
wait;
end process process_03_2_b;
end architecture test;
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