diff options
Diffstat (limited to 'testsuite/vests/vhdl-ams/ashenden/compliant/subprograms/signal_generator.vhd')
-rw-r--r-- | testsuite/vests/vhdl-ams/ashenden/compliant/subprograms/signal_generator.vhd | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/testsuite/vests/vhdl-ams/ashenden/compliant/subprograms/signal_generator.vhd b/testsuite/vests/vhdl-ams/ashenden/compliant/subprograms/signal_generator.vhd new file mode 100644 index 000000000..b61730f6c --- /dev/null +++ b/testsuite/vests/vhdl-ams/ashenden/compliant/subprograms/signal_generator.vhd @@ -0,0 +1,64 @@ + +-- 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 + +-- not in book + +entity signal_generator is + generic ( period : delay_length := 20 ns; + pulse_count : natural := 5 ); +end entity signal_generator; + +-- end not in book + + +library ieee; use ieee.std_logic_1164.all; + +architecture top_level of signal_generator is + + signal raw_signal : std_ulogic; + -- . . . + + procedure generate_pulse_train ( width, separation : in delay_length; + number : in natural; + signal s : out std_ulogic ) is + begin + for count in 1 to number loop + s <= '1', '0' after width; + wait for width + separation; + end loop; + end procedure generate_pulse_train; + +begin + + raw_signal_generator : process is + begin + -- . . . + generate_pulse_train ( width => period / 2, + separation => period - period / 2, + number => pulse_count, + s => raw_signal ); + -- . . . + -- not in book + wait; + -- end not in book + end process raw_signal_generator; + + -- . . . + +end architecture top_level; |