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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_04_ch_04_09.vhd,v 1.2 2001-10-26 16:29:37 paw Exp $
-- $Revision: 1.2 $
--
-- ---------------------------------------------------------------------
entity ch_04_09 is
end entity ch_04_09;
----------------------------------------------------------------
architecture test of ch_04_09 is
begin
process_04_3_c : process is
-- code from book:
subtype name is string(1 to 20);
type display_string is array (integer range 0 to 19) of character;
variable item_name : name;
variable display : display_string;
--
subtype big_endian_upper_halfword is bit_vector(0 to 15);
subtype little_endian_upper_halfword is bit_vector(31 downto 16);
variable big : big_endian_upper_halfword;
variable little : little_endian_upper_halfword;
-- end of code from book
begin
-- error: Incompatible types for assignment
-- display := item_name; -- ilegal
item_name := (others => 'A');
little := x"AAAA";
-- code from book:
display := display_string(item_name);
--
big := little;
little := big;
-- end of code from book
wait;
end process process_04_3_c;
----------------
end architecture test;
|
