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