xue.vhd

vhdl代码实现8位cpu功能

library ieee;
use ieee.std_logic_1164.all;

package  xue is

	constant idle : std_logic_vector( 3 downto 0 ) := "0000"; 
	constant load : std_logic_vector( 3 downto 0 ) := "0001";
	constant move : std_logic_vector( 3 downto 0 ) := "0010";
	constant addp : std_logic_vector( 3 downto 0 ) := "0011";
	constant subp : std_logic_vector( 3 downto 0 ) := "0100";
	constant andp : std_logic_vector( 3 downto 0 ) := "0101";
	constant orp : std_logic_vector( 3 downto 0 )  := "0110";
	constant xorp : std_logic_vector( 3 downto 0 ) := "0111";
	constant shrp : std_logic_vector( 3 downto 0 ) := "1000";
	constant shlp : std_logic_vector( 3 downto 0 ) := "1001";
	constant swap : std_logic_vector( 3 downto 0 ) := "1010";
	constant jmp : std_logic_vector( 3 downto 0 )  := "1011";
	constant jz : std_logic_vector( 3 downto 0 )   := "1100";
	constant read : std_logic_vector( 3 downto 0 ) := "1101";
	constant write : std_logic_vector( 3 downto 0 ):= "1110";
	constant stop : std_logic_vector( 3 downto 0 ) := "1111";
end xue;