1
2-- Copyright (C) 1996 Morgan Kaufmann Publishers, Inc
3
4-- This file is part of VESTs (Vhdl tESTs).
5
6-- VESTs is free software; you can redistribute it and/or modify it
7-- under the terms of the GNU General Public License as published by the
8-- Free Software Foundation; either version 2 of the License, or (at
9-- your option) any later version.
10
11-- VESTs is distributed in the hope that it will be useful, but WITHOUT
12-- ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13-- FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14-- for more details.
15
16-- You should have received a copy of the GNU General Public License
17-- along with VESTs; if not, write to the Free Software Foundation,
18-- Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
19
20-- ---------------------------------------------------------------------
21--
22-- $Id: ch_04_ch_04_09.vhd,v 1.2 2001-10-26 16:29:37 paw Exp $
23-- $Revision: 1.2 $
24--
25-- ---------------------------------------------------------------------
26
27entity ch_04_09 is
28
29end entity ch_04_09;
30
31
32----------------------------------------------------------------
33
34
35architecture test of ch_04_09 is
36begin
37
38
39  process_04_3_c : process is
40
41                             -- code from book:
42
43                             subtype name is string(1 to 20);
44                           type display_string is array (integer range 0 to 19) of character;
45
46                           variable item_name : name;
47                           variable display : display_string;
48
49                           --
50
51                           subtype big_endian_upper_halfword is bit_vector(0 to 15);
52                           subtype little_endian_upper_halfword is bit_vector(31 downto 16);
53
54                           variable big : big_endian_upper_halfword;
55                           variable little : little_endian_upper_halfword;
56
57                           -- end of code from book
58
59  begin
60
61    -- error: Incompatible types for assignment
62    -- display := item_name;  -- ilegal
63
64    item_name := (others => 'A');
65
66    little := x"AAAA";
67
68    -- code from book:
69
70    display := display_string(item_name);
71
72    --
73
74    big := little;
75    little := big;
76
77    -- end of code from book
78
79    wait;
80  end process process_04_3_c;
81
82
83  ----------------
84
85
86end architecture test;
87