--! Test baud_generator module
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--! @file
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--! @brief Test baud_generator module
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--! Use standard library and import the packages (std_logic_1164,std_logic_unsigned,std_logic_arith)
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library ieee;
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library ieee;
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use ieee.std_logic_1164.all;
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use ieee.std_logic_1164.all;
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use ieee.std_logic_unsigned.all;
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use ieee.std_logic_unsigned.all;
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use ieee.std_logic_arith.all;
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use ieee.std_logic_arith.all;
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--! Use Global Definitions package
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--! Use Global Definitions package
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use work.pkgDefinitions.all;
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use work.pkgDefinitions.all;
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ENTITY testBaud_generator IS
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ENTITY testBaud_generator IS
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END testBaud_generator;
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END testBaud_generator;
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--! @brief Test baud_generator module
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--! @details Exercise the baud generator with 50Mhz clock and dividing by 434, finally checking for period of 8.68 us
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ARCHITECTURE behavior OF testBaud_generator IS
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ARCHITECTURE behavior OF testBaud_generator IS
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COMPONENT baud_generator
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COMPONENT baud_generator
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Port ( rst : in STD_LOGIC; --! Reset Input
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Port ( rst : in STD_LOGIC; --! Reset Input
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clk : in STD_LOGIC; --! Clock input
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clk : in STD_LOGIC; --! Clock input
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cycle_wait : in STD_LOGIC_VECTOR ((nBitsLarge-1) downto 0); --! Number of cycles to wait for baud generation
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cycle_wait : in STD_LOGIC_VECTOR ((nBitsLarge-1) downto 0); --! Number of cycles to wait for baud generation
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baud_oversample : out std_logic; --! Oversample(8x) version of baud (Used on serial_receiver)
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baud_oversample : out std_logic; --! Oversample(8x) version of baud (Used on serial_receiver)
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baud : out STD_LOGIC); --! Baud generation output (Used on serial_transmitter)
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baud : out STD_LOGIC); --! Baud generation output (Used on serial_transmitter)
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END COMPONENT;
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END COMPONENT;
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--Inputs
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--Inputs
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signal rst : std_logic := '0'; --! Signal to connect with UUT
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signal rst : std_logic := '0'; --! Signal to connect with UUT
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signal clk : std_logic := '0'; --! Signal to connect with UUT
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signal clk : std_logic := '0'; --! Signal to connect with UUT
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signal cycle_wait : std_logic_vector((nBitsLarge-1) downto 0) := (others => '0'); --! Signal to connect with UUT
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signal cycle_wait : std_logic_vector((nBitsLarge-1) downto 0) := (others => '0'); --! Signal to connect with UUT
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--Outputs
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--Outputs
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signal baud : std_logic; --! Signal to connect with UUT
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signal baud : std_logic; --! Signal to connect with UUT
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signal baud_oversample : std_logic; --! Signal to connect with UUT
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signal baud_oversample : std_logic; --! Signal to connect with UUT
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-- Clock period definitions (1.8432MHz)
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-- Clock period definitions (1.8432MHz)
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constant clk_period : time := 0.543 us; -- 0.543us (1.8432Mhz) 2ns (50Mhz)
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constant clk_period : time := 20 ns; -- 0.543us (1.8432Mhz) 20ns (50Mhz)
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BEGIN
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BEGIN
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--! Instantiate the Unit Under Test (UUT)
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--! Instantiate the Unit Under Test (UUT)
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uut: baud_generator PORT MAP (
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uut: baud_generator PORT MAP (
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rst => rst,
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rst => rst,
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clk => clk,
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clk => clk,
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cycle_wait => cycle_wait,
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cycle_wait => cycle_wait,
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baud_oversample => baud_oversample,
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baud_oversample => baud_oversample,
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baud => baud
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baud => baud
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);
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);
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-- Clock process definitions
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-- Clock process definitions
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clk_process :process
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clk_process :process
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begin
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begin
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clk <= '0';
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clk <= '0';
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wait for clk_period/2;
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wait for clk_period/2;
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clk <= '1';
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clk <= '1';
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wait for clk_period/2;
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wait for clk_period/2;
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end process;
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end process;
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-- Stimulus process
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-- Stimulus process
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stim_proc: process
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stim_proc: process
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variable t1 : time;
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variable t2 : time;
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variable period : time; -- 1/115200 = 8.68 us
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begin
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begin
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-- Test the baud generator waiting for 16 clock cycles for 1.8432MHz clock
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-- Test the baud generator waiting for 434 clock cycles from 50MHz clock
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rst <= '1';
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rst <= '1';
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cycle_wait <= conv_std_logic_vector(16, (nBitsLarge));
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cycle_wait <= conv_std_logic_vector(434, (nBitsLarge)); -- 50000000/115200
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wait for 2 ns;
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wait for clk_period;
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rst <= '0';
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rst <= '0';
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wait for clk_period*300;
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wait until baud = '1';
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t1 := now; -- Get current simulation time
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wait until baud = '0';
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wait until baud = '1';
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t2 := now; -- Get current simulation time
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wait until baud = '0';
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wait until baud = '1';
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report "Current sim time=" & time'image(now);
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period := t2 - t1;
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-- Verify if we have the right period 1/115200 = 8.68 us
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assert period = 8.68 us report "Wrong period expecter 8.68 us. got: "& time'image(period) severity failure;
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-- Stop Simulation
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-- Stop Simulation
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assert false report "NONE. End of simulation." severity failure;
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assert false report "NONE. End of simulation." severity failure;
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wait;
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wait;
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end process;
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end process;
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END;
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END;
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