Subversion Repositories uart_block

--! @file

--! @brief Test communication block

--! Use standard library and import the packages (std_logic_1164,std_logic_unsigned,std_logic_arith)

LIBRARY ieee;

USE ieee.std_logic_1164.ALL;

use ieee.std_logic_unsigned.all;

use ieee.std_logic_arith.all;

--! Use Global Definitions package

use work.pkgDefinitions.all;

ENTITY testUart_communication_block IS

END testUart_communication_block;

--! @brief Test communication block

--! @details This will include all blocks used in uart (transmiter, receiver, baud generator)

ARCHITECTURE behavior OF testUart_communication_block IS

    -- Component Declaration for the Unit Under Test (UUT)

    COMPONENT uart_communication_blocks

    Port ( rst : in  STD_LOGIC;                                                                                                                 --! Global reset

           clk : in  STD_LOGIC;                                                                                                                 --! Global clock

                          cycle_wait_baud : in std_logic_vector((nBitsLarge-1) downto 0);        --! Number of cycles to wait in order to generate desired baud

           byte_tx : in  STD_LOGIC_VECTOR ((nBits-1) downto 0);                          --! Byte to transmit

           byte_rx : out  STD_LOGIC_VECTOR ((nBits-1) downto 0);                         --! Byte to receive

           data_sent_tx : out  STD_LOGIC;                                                                                               --! Indicate that byte has been sent

           data_received_rx : out  STD_LOGIC;                                                                           --! Indicate that we got a byte

                          serial_out : out std_logic;                                                                                                   --! Uart serial out

                          serial_in : in std_logic;                                                                                                     --! Uart serial in

           start_tx : in  STD_LOGIC);                                                                                                   --! Initiate transmission

    END COMPONENT;

   --Inputs

   signal rst : std_logic := '0';                                                                                                                                                        --! Signal to connect with UUT

   signal clk : std_logic := '0';                                                                                                                                                        --! Signal to connect with UUT

   signal cycle_wait_baud : std_logic_vector((nBitsLarge-1) downto 0) := (others => '0'); --! Signal to connect with UUT

   signal byte_tx : std_logic_vector((nBits-1) downto 0) := (others => '0');                                      --! Signal to connect with UUT

   signal serial_in : std_logic := '0';                                                                                                                                  --! Signal to connect with UUT

   signal start_tx : std_logic := '0';                                                                                                                                           --! Signal to connect with UUT

        --Outputs

   signal byte_rx : std_logic_vector((nBits-1) downto 0);                                                                                        --! Signal to connect with UUT

   signal data_sent_tx : std_logic;                                                                                                                                                     --! Signal to connect with UUT

   signal data_received_rx : std_logic;                                                                                                                                 --! Signal to connect with UUT

   signal serial_out : std_logic;                                                                                                                                                       --! Signal to connect with UUT

   -- Clock period definitions   

        constant clk_period : time := 20 ns; -- 0.543us (1.8432Mhz) 20ns (50Mhz)

BEGIN

        --! Instantiate the Unit Under Test (UUT)

   uut: uart_communication_blocks PORT MAP (

          rst => rst,

          clk => clk,

          cycle_wait_baud => cycle_wait_baud,

          byte_tx => byte_tx,

          byte_rx => byte_rx,

          data_sent_tx => data_sent_tx,

          data_received_rx => data_received_rx,

          serial_out => serial_out,

          serial_in => serial_in,

          start_tx => start_tx

        );

   -- Clock process definitions

   clk_process :process

   begin

                clk <= '0';

                wait for clk_period/2;

                clk <= '1';

                wait for clk_period/2;

   end process;

   -- Stimulus process

   stim_proc: process

   begin

      -- Setup communication blocks

                rst <= '1';

                serial_in <= '1'; -- Idle..

                cycle_wait_baud <= conv_std_logic_vector(434, (nBitsLarge));

                start_tx <= '0';

      wait for 2 ns;

                rst <= '0';

                -- Send data..

                start_tx <= '1';

                byte_tx <= "01010101";

                wait until data_sent_tx = '1';

      wait for clk_period*3;

                start_tx <= '0';

                wait for clk_period*3;

                start_tx <= '1';

                byte_tx <= "11000100";

                wait until data_sent_tx = '1';

                wait for clk_period*3;

                start_tx <= '0';

                wait for clk_period*3;

                -- Receive data...

                -- Receive 0x55 value (01010101)

                serial_in <= '0'; -- Start bit

                wait for 8.68 us;

                serial_in <= '1';

      wait for 8.68 us;

                serial_in <= '0';

      wait for 8.68 us;

                serial_in <= '1';

      wait for 8.68 us;

                serial_in <= '0';

      wait for 8.68 us;

                serial_in <= '1';

      wait for 8.68 us;

                serial_in <= '0';

      wait for 8.68 us;

                serial_in <= '1';

      wait for 8.68 us;

                serial_in <= '0';

      wait for 8.68 us;

                -- Stop bit here

                serial_in <= '1';

                wait for clk_period*200;

                -- Receive 0xC4 value (11000100)

                serial_in <= '0'; -- Start bit

                wait for 8.68 us;

                serial_in <= '0';

      wait for 8.68 us;

                serial_in <= '0';

      wait for 8.68 us;

                serial_in <= '1';

      wait for 8.68 us;

                serial_in <= '0';

      wait for 8.68 us;

                serial_in <= '0';

      wait for 8.68 us;

                serial_in <= '0';

      wait for 8.68 us;

                serial_in <= '1';

      wait for 8.68 us;

                serial_in <= '1';

      wait for 8.68 us;

                -- Stop bit here

                serial_in <= '1';

                wait for clk_period*200;

      -- Stop Simulation

                assert false report "NONE. End of simulation." severity failure;

   end process;

END;