Subversion Repositories mblite

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--

--      Input file         : mblite_stdio.vhd

--      Design name        : mblite_stdio

--      Author             : Tamar Kranenburg

--      Company            : Delft University of Technology

--                         : Faculty EEMCS, Department ME&CE

--                         : Systems and Circuits group

--

--      Description        : Simulates standard output using stdio package

--

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LIBRARY ieee;

USE ieee.std_logic_1164.ALL;

USE ieee.std_logic_unsigned.ALL;

LIBRARY mblite;

USE mblite.config_Pkg.ALL;

USE mblite.core_Pkg.ALL;

USE std.textio.ALL;

ENTITY mblite_stdio IS PORT

(

    dmem_i : OUT dmem_in_type;

    dmem_o : IN dmem_out_type;

    clk_i  : IN std_ulogic

);

END mblite_stdio;

ARCHITECTURE arch OF mblite_stdio IS

BEGIN

    -- Character device

    stdio: PROCESS(clk_i)

            VARIABLE s    : line;

            VARIABLE byte : std_ulogic_vector(7 DOWNTO 0);

            VARIABLE char : character;

        BEGIN

            dmem_i.dat_i <= (OTHERS => '0');

            dmem_i.ena_i <= '1';

            IF rising_edge(clk_i) THEN

                IF dmem_o.ena_o = '1' THEN

                    IF dmem_o.we_o = '1' THEN

                    -- WRITE STDOUT

                        CASE dmem_o.sel_o IS

                            WHEN "0001" => byte := dmem_o.dat_o( 7 DOWNTO  0);

                            WHEN "0010" => byte := dmem_o.dat_o(15 DOWNTO  8);

                            WHEN "0100" => byte := dmem_o.dat_o(23 DOWNTO 16);

                            WHEN "1000" => byte := dmem_o.dat_o(31 DOWNTO 24);

                            WHEN OTHERS => NULL;

                        END CASE;

                        char := character'val(my_conv_integer(byte));

                        IF byte = X"0D" THEN

                            -- Ignore character 13

                        ELSIF byte = X"0A" THEN

                            -- Writeline on character 10 (newline)

                            writeline(output, s);

                        ELSE

                            -- Write to buffer

                            write(s, char);

                        END IF;

                    END IF;

                END IF;

            END IF;

    END PROCESS;

END arch;