token_tb.vhd

同步串行数据发送电路SSDT的基本功能是将并行数据转换成串行数据并进行同步发送。系统写入和读出时序完全兼容Intel8086时序。 系统以同步信号开始连续发送四个字节

Library IEEE;
USE IEEE.std_logic_1164.all; 

Entity TOKEN_TB IS
End TOKEN_TB;

Architecture behavior of TOKEN_TB  is 
component TOKEN
Port( CLK:   in std_logic; 
      RST:   in std_logic;
      DATA:  in std_logic_vector(7 downto 0);
      CS:    in std_logic;
      A0:    in std_logic;
      WR:    in std_logic;
      READY: in std_logic;
      REQ:   out std_logic;
      BUSY:  out std_logic;
      D_OUT: out std_logic;
      TOKEN_IN: in std_logic;
      TOKEN_OUT: out std_logic);    
end component;

signal CLK:   std_logic; 
signal RST:   std_logic;
signal DATA:  std_logic_vector(7 downto 0);
signal CS:    std_logic;
signal A0:    std_logic;
signal WR:    std_logic;
signal READY: std_logic;
signal REQ:   std_logic;
signal BUSY:  std_logic;
signal D_OUT: std_logic;
signal TOKEN_IN:  std_logic;
signal TOKEN_OUT: std_logic;
      

constant T_cycle : time := 1 us;

begin
u1: TOKEN 
    port map ( CLK      =>   CLK,    
               RST      =>   RST,      
               DATA     =>   DATA,     
               CS       =>   CS,        
               A0       =>   A0,        
               WR       =>   WR,        
               READY    =>   READY,     
               REQ      =>   REQ,       
               BUSY     =>   BUSY,      
               D_OUT    =>   D_OUT,     
               TOKEN_IN =>   TOKEN_IN,  
               TOKEN_OUT=>   TOKEN_OUT) ;

Process	   	                    
Begin	  
    CLK<='1';
    wait for T_cycle/2;
    CLK<='0';
    wait for T_cycle/2;
End process; 	


process

procedure RSTPRO is
begin
    RST<='0';
    wait for T_cycle*2;
    wait for T_cycle/20;
    RST<='1';
    wait for T_cycle*2;
end ;

procedure R1R2PRO is
begin
    CS<='0';
    WR<='0';
    A0<='0';
    DATA<=X"44";
    wait for T_cycle;
    CS<='1';
    WR<='1';
    wait for T_cycle;
    CS<='0';
    WR<='0';
    A0<='1';
    DATA<=X"55";
    wait for T_cycle;
    CS<='1';
    WR<='1';
    wait for T_cycle;
end ;

procedure TOKEN_INPRO is
begin
    wait for T_cycle*2;
    TOKEN_IN<='1';
    wait for T_cycle*2;
    wait for T_cycle/2;
    TOKEN_IN<='0'; 
    wait for T_cycle/2;
end ;


procedure DATAPRO is
begin
    CS<='0';
    WR<='0';
    READY<='1';
    DATA<=X"01";
    wait for T_cycle;
    CS<='1';
    WR<='1';
    READY<='0';
    wait for T_cycle*2;
    CS<='0';
    WR<='0';
    READY<='1';
    DATA<=X"02";
    wait for T_cycle;
    CS<='1';
    WR<='1';
    READY<='0';
    wait for T_cycle*2;
     CS<='0';
    WR<='0';
    READY<='1';
    DATA<=X"03";
    wait for T_cycle;
    CS<='1';
    WR<='1';
    READY<='0';
    wait for T_cycle*2;
     CS<='0';
    WR<='0';
    READY<='1';
    DATA<=X"04";
    wait for T_cycle;
    CS<='1';
    WR<='1';
    READY<='0';
    wait for T_cycle*2;
     CS<='0';
    WR<='0';
    READY<='1';
    DATA<=X"05";
    wait for T_cycle;
    CS<='1';
    WR<='1';
    READY<='0';
    wait for T_cycle*2;
     CS<='0';
    WR<='0';
    READY<='1';
    DATA<=X"06";
    wait for T_cycle;
    CS<='1';
    WR<='1';
    READY<='0';
    wait for T_cycle*60; 
end ;


begin
    RSTPRO;
    R1R2PRO;
    TOKEN_INPRO;
    DATAPRO;
end process;

End behavior;