Files
vhdl/lib/uart/tb_juart_rx.vhd
T
jens 3638a97abf - added J-UART
git-svn-id: http://moon:8086/svn/vhdl/trunk@1341 cc03376c-175c-47c8-b038-4cd826a8556b
2016-12-17 17:54:33 +00:00

105 lines
2.6 KiB
VHDL

-------------------------------------------------------------------------
-- Project: JCPU, a portable 8-bit RISC CPU written in VHDL
-- This file: cpu_embedded using cpu_core and rom
--
-- Copyright (C) 2007 J. Ahrensfeld
--
-- This program 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 3 of the License, or
-- (at your option) any later version.
--
-- This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
--
-- For questions and ideas, please contact the author at jens@jayfield.org
--
--------------------------------------------------------------------------
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.numeric_std.ALL;
entity tb_juart_rx is
end;
architecture behave of tb_juart_rx is
-- Number of user data words for simulation
constant CLK_PERIOD : time := 10 ns;
signal rst : std_logic := '1';
signal clk : std_logic := '1';
signal en_16_x_baud : std_logic := '1';
signal serial_in : std_logic := '1';
signal data_strobe : std_logic;
signal data_out : unsigned(7 downto 0);
signal serial_word : unsigned(7 downto 0) := X"AA";
signal data_reg : unsigned(7 downto 0);
begin
inst_juart_rx : entity work.juart_rx
PORT MAP
(
rst => rst,
clk => clk,
en_16_x_baud => en_16_x_baud,
data_strobe => data_strobe,
data_out => data_out,
serial_in => serial_in
);
CLK_GEN: process
begin
wait for CLK_PERIOD/2;
clk <= not clk;
end process;
PROC_DATAREG: process
begin
wait until rising_edge(clk) and data_strobe = '1';
data_reg <= data_out;
end process;
------------------------------------------------------------------------------------------
STIMULUS: process
begin
wait for 3*CLK_PERIOD;
rst <= '0';
serial_word <= X"AA";
wait for 16*CLK_PERIOD;
serial_in <= '0';
wait for 16*CLK_PERIOD;
for i in serial_word'length-1 downto 0 loop
serial_in <= serial_word(i);
wait for 16*CLK_PERIOD;
end loop;
serial_in <= '1';
wait for 16*CLK_PERIOD;
serial_word <= X"55";
serial_in <= '0';
wait for 16*CLK_PERIOD;
for i in serial_word'length-1 downto 0 loop
serial_in <= serial_word(i);
wait for 16*CLK_PERIOD;
end loop;
serial_in <= '1';
wait;
end process;
end architecture behave;