多状态机

LIBRARY ieee;
USE ieee.std_logic_1164.all;


LIBRARY ieee;
USE ieee.std_logic_unsigned.all;

ENTITY SHELL_DUOZTJI IS
 PORT (CLK,RESET: IN std_logic;
  dcounter0,dcounter1 : OUT std_logic);
 SIGNAL BP_dcounter0,BP_dcounter1,readcounter0,readcounter1: std_logic;
END;

ARCHITECTURE BEHAVIOR. OF SHELL_DUOZTJI IS
 SIGNAL sreg : std_logic_vector (1 DOWNTO 0);
 SIGNAL next_sreg : std_logic_vector (1 DOWNTO 0);
 CONSTANT m0full : std_logic_vector (1 DOWNTO 0) :="00";
 CONSTANT m0writewait : std_logic_vector (1 DOWNTO 0) :="01";
 CONSTANT STATE0 : std_logic_vector (1 DOWNTO 0) :="10";
 CONSTANT write0 : std_logic_vector (1 DOWNTO 0) :="11";

 SIGNAL sreg1 : std_logic_vector (1 DOWNTO 0);
 SIGNAL next_sreg1 : std_logic_vector (1 DOWNTO 0);
 CONSTANT m0empty : std_logic_vector (1 DOWNTO 0) :="00";
 CONSTANT m0readwait : std_logic_vector (1 DOWNTO 0) :="01";
 CONSTANT read0 : std_logic_vector (1 DOWNTO 0) :="10";
 CONSTANT STATE1 : std_logic_vector (1 DOWNTO 0) :="11";

 SIGNAL next_BP_dcounter0,next_BP_dcounter1,next_readcounter0,
  next_readcounter1 : std_logic;
 SIGNAL BP_dcounter : std_logic_vector (1 DOWNTO 0);
 SIGNAL dcounter : std_logic_vector (1 DOWNTO 0);
 SIGNAL readcounter : std_logic_vector (1 DOWNTO 0);
BEGIN
 PROCESS (CLK, next_sreg, next_BP_dcounter1, next_BP_dcounter0)
 BEGIN
  IF CLK='1' AND CLK'event THEN
   sreg <= next_sreg;
   BP_dcounter1 <= next_BP_dcounter1;
   BP_dcounter0 <= next_BP_dcounter0;
  END IF;
 END PROCESS;

 PROCESS (CLK, next_sreg1, next_readcounter1, next_readcounter0)
 BEGIN
  IF CLK='1' AND CLK'event THEN
   sreg1 <= next_sreg1;
   readcounter1 <= next_readcounter1;
   readcounter0 <= next_readcounter0;
  END IF;
 END PROCESS;

 PROCESS (sreg,sreg1,BP_dcounter0,BP_dcounter1,readcounter0,readcounter1,
  RESET,BP_dcounter,readcounter)
 BEGIN
next_BP_dcounter0 <= BP_dcounter0;next_BP_dcounter1 <= BP_dcounter1;
next_readcounter0 <= readcounter0;next_readcounter1 <= readcounter1;
BP_dcounter <= (( std_logic_vector'(BP_dcounter1, BP_dcounter0)));
readcounter <= (( std_logic_vector'(readcounter1, readcounter0)));

next_sreg<=m0full;
next_sreg1<=m0empty;

IF ( RESET='1' ) THEN
 next_sreg<=STATE0;
 BP_dcounter <= (std_logic_vector'("00"));
ELSE
 CASE sreg IS
  WHEN m0full =>
   next_sreg<=m0writewait;
   BP_dcounter <= (( std_logic_vector'(BP_dcounter1, BP_dcounter0)));
  WHEN m0writewait =>
  IF (  (sreg1=m0empty)) THEN
   next_sreg<=write0;
   BP_dcounter <= (( std_logic_vector'(BP_dcounter1, BP_dcounter0)) +       std_logic_vector'("01"));
  ELSE
   next_sreg<=m0writewait;
   BP_dcounter <= (( std_logic_vector'(BP_dcounter1, BP_dcounter0)));
  END IF;
   WHEN STATE0 =>
   next_sreg<=write0;
   BP_dcounter <= (( std_logic_vector'(BP_dcounter1, BP_dcounter0)) +
      std_logic_vector'("01"));
  WHEN write0 =>
  IF ( BP_dcounter0='1' AND BP_dcounter1='1' ) THEN
   next_sreg<=m0full;
   BP_dcounter <= (std_logic_vector'("00"));
  ELSE
      next_sreg<=write0;
   BP_dcounter <= (( std_logic_vector'(BP_dcounter1, BP_dcounter0)) +
       std_logic_vector'("01"));
  END IF;
  WHEN THERS =>
   END CASE;
 END IF;

IF ( RESET='1' ) THEN
 next_sreg1<=STATE1;
 readcounter <= (std_logic_vector'("00"));
ELSE
CASE sreg1 IS
WHEN m0empty =>
 next_sreg1<=m0readwait;
 readcounter <= (( std_logic_vector'(readcounter1, readcounter0)));
WHEN m0readwait =>
 IF (  (sreg=m0full)) THEN
     next_sreg1<=read0;
 readcounter <= (( std_logic_vector'(readcounter1, readcounter0)) +
       std_logic_vector'("01"));
  ELSE
  next_sreg1<=m0readwait;
  readcounter <= (( std_logic_vector'(readcounter1, readcounter0)));
  END IF;
WHEN read0 =>
 IF ( readcounter0='1' AND readcounter1='1' ) THEN
  next_sreg1<=m0empty;
  readcounter <= (std_logic_vector'("00"));
 ELSE
  next_sreg1<=read0;
  readcounter <= (( std_logic_vector'(readcounter1, readcounter0)) +
       std_logic_vector'("01"));
 END IF;
WHEN STATE1 =>
 IF (  (sreg=m0full)) THEN
  next_sreg1<=read0;
  readcounter <= (( std_logic_vector'(readcounter1, readcounter0)) + std_logic_vector'("01"));
 ELSE
  next_sreg1<=STATE1;
  readcounter <= (( std_logic_vector'(readcounter1, readcounter0)));
 END IF;
WHEN THERS =>
  END CASE;
END IF;

next_BP_dcounter1 <= BP_dcounter(1);
  next_BP_dcounter0 <= BP_dcounter(0);
  next_readcounter1 <= readcounter(1);
  next_readcounter0 <= readcounter(0);
 END PROCESS;

 PROCESS (BP_dcounter0,BP_dcounter1,dcounter)
 BEGIN
  dcounter <= (( std_logic_vector'(BP_dcounter1, BP_dcounter0)));
  dcounter0 <= dcounter(0);
  dcounter1 <= dcounter(1);
 END PROCESS;
END BEHAVIOR;

LIBRARY ieee;
USE ieee.std_logic_1164.all;
LIBRARY ieee;
USE ieee.std_logic_unsigned.all;

ENTITY DUOZTJI IS
 PORT (dcounter : OUT std_logic_vector (1 DOWNTO 0);
  CLK,RESET: IN std_logic);
END;

ARCHITECTURE BEHAVIOR. OF DUOZTJI IS
 COMPONENT SHELL_DUOZTJI
  PORT (CLK,RESET: IN std_logic;
   dcounter0,dcounter1 : OUT std_logic);
 END COMPONENT;
BEGIN
 SHELL1_DUOZTJI : SHELL_DUOZTJI PORT MAP (CLK=>CLK,RESET=>RESET,dcounter0=>
  dcounter(0),dcounter1=>dcounter(1));
END BEHAVIOR;

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