source: firmware/FAD/FACT_FAD_TB_lib/hdl/phase_shifter_tester_beha.vhd@ 17689

--
-- VHDL Architecture FACT_FAD_TB_lib.phase_shifter_tester.beha
--
-- Created:
--          by - dneise.UNKNOWN (E5B-LABOR6)
--          at - 14:39:41 12.02.2011
--
-- using Mentor Graphics HDL Designer(TM) 2009.2 (Build 10)
--
LIBRARY ieee;
USE ieee.std_logic_1164.ALL;
USE IEEE.NUMERIC_STD.ALL;
LIBRARY FACT_FAD_lib;
USE FACT_FAD_lib.fad_definitions.ALL;

ENTITY phase_shifter_tester IS
   PORT( 
      -- interface to: clock_generator_variable_PS_struct.vhd
      
      clk:in std_logic;
      
      
      PSCLK       : IN     std_logic;
      PSEN        : IN     std_logic;
      PSINCDEC    : IN     std_logic;                      -- default is 'incrementing'
      offset      : IN     std_logic_vector (7 DOWNTO 0);
      ready       : IN     std_logic;
      rst         : IN     std_logic;                      --asynch in of DCM
      -- status:
      shifting    : IN     std_logic;
      LOCKED      : OUT    std_logic;                      -- when is this going high?
      PSDONE      : OUT    std_logic;                      -- will pulse once, if phase shifting was done.
      direction   : OUT    std_logic;                      -- corresponds to 'PSINCDEC'
      reset_DCM   : OUT    std_logic;                      -- asynch in: orders us, to reset the DCM
      -- interface to: w5300_modul.vhd
      shift_phase : OUT    std_logic
   );

-- Declarations

END phase_shifter_tester ;

--
ARCHITECTURE beha OF phase_shifter_tester IS
constant DIVIDER : integer  := 25;
        signal bla : std_logic := '0';
        signal  Z: integer range 0 to DIVIDER - 1;
        signal  Y: integer range 0 to DIVIDER - 1;
        signal ping : std_logic := '0';
        signal locken : std_logic := '1';
BEGIN

LOCKED <= '1' and locken;

        
        process
                begin
                        direction <= '1';
                        shift_phase <='0';                      
                        reset_DCM <= '0';
                        
                        
                        
                        wait for 1us;
                        shift_phase <='1';                      
                        wait for 100ns;
                        shift_phase <='0';
      wait for 1us;
      shift_phase <='1';                        
      wait for 100ns;
      shift_phase <='0';
      wait for 1us;
      shift_phase <='1';                        
      wait for 100ns;
      shift_phase <='0';

      wait for 1us;
      reset_DCM <='1';                  
      wait for 500ns;
      reset_DCM <='0';
      
        end process;
        
        -- DCM PSDONE simulation
        -- after DCM receives PSEN high it will start shifting and then .. after a while rise PSDONE for 1 cycle.
        -- let's see how to simulate this here.

                        clk_proc: process (clk)

                        begin
                                
                                if rising_edge(clk) then
                                        if (PSEN = '1') then 
                                                bla <= '1';
                                        end if;
                                        
                                if (bla = '1') then
                                        if (Z < DIVIDER - 1) then 
                                                Z <= Z + 1;
                                        else 
                                                Z <= 0;
                                                bla <= '0';     
                                        end if;
                                        if (Z = 0) then 
                                                PSDONE <= '0';  
                                        end if;
                                        if (Z = DIVIDER -2 ) then 
                                                PSDONE <= '1';

                                        end if;
                                        if (Z = DIVIDER -1 ) then 
                                                PSDONE <= '0';

                                        end if;

                                end if; --bla =1

                                end if;
                        end process clk_proc;

                        process (clk)
                        begin
                                if (rst = '1') then 
                                                                        ping <= '1';
                                                                        locken <= '0';
                                end if;

                                                                if rising_edge(clk) then                                        
                                                                        if (ping = '1') then
                                                                                                if (Y < DIVIDER - 1) then 
                                                                                                        Y <= Y + 1;
                                                                                                else 
                                                                                                        Y <= 0;
                                                                                                        ping <= '0';    
                                                                                                end if;
                                                                        
                                                                        
                                                                        if (Y = DIVIDER -1 ) then 
                                                                                locken <= '1';

                                        end if;

                                end if; --bla =1

                                end if;
                        end process;

                        


END ARCHITECTURE beha;