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-- Copyright (C) 2002 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
entity bv_lt is
end entity bv_lt;
architecture test of bv_lt is
-- code from book
procedure bv_lt ( bv1, bv2 : in bit_vector; result : out boolean ) is
variable tmp1 : bit_vector(bv1'range) := bv1;
variable tmp2 : bit_vector(bv2'range) := bv2;
begin
tmp1(tmp1'left) := not tmp1(tmp1'left);
tmp2(tmp2'left) := not tmp2(tmp2'left);
result := tmp1 < tmp2;
end procedure bv_lt;
-- end code from book
begin
stimulus : process is
subtype byte is bit_vector(0 to 7);
variable result : boolean;
begin
bv_lt( byte'(X"02"), byte'(X"04"), result );
assert result;
bv_lt( byte'(X"02"), byte'(X"02"), result );
assert not result;
bv_lt( byte'(X"02"), byte'(X"02"), result );
assert not result;
bv_lt( byte'(X"FC"), byte'(X"04"), result );
assert result;
bv_lt( byte'(X"04"), byte'(X"FC"), result );
assert not result;
bv_lt( byte'(X"FC"), byte'(X"FC"), result );
assert not result;
bv_lt( byte'(X"FC"), byte'(X"FE"), result );
assert result;
bv_lt( byte'(X"FE"), byte'(X"FC"), result );
assert not result;
wait;
end process stimulus;
end architecture test;
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