tonetaba.vhd

来自「基于max—plus2开发环境」· VHDL 代码 · 共 35 行

LIBRARY IEEE;
USE IEEE.STD_LOGIC_1164.ALL;
ENTITY TONETABA IS
  PORT(INDEX: IN INTEGER RANGE 0 TO 15;
       CODE:OUT INTEGER RANGE 0 TO 15;
       HIGH:OUT STD_LOGIC;
       TONE:OUT INTEGER RANGE 0 TO 16#7FF#);
END TONETABA;
ARCHITECTURE one OF TONETABA IS
BEGIN
  SEARCH:PROCESS(INDEX)
  BEGIN
    CASE INDEX IS
      WHEN 0  =>TONE<=2047;CODE<=0;HIGH<='0';
      WHEN 1  =>TONE<=773;CODE<=1;HIGH<='0';
      WHEN 2  =>TONE<=912;CODE<=2;HIGH<='0';
      WHEN 3  =>TONE <=1036;CODE<=3;HIGH<='0';
      WHEN 4  =>TONE <=1116;CODE<=4;HIGH<='0';
      WHEN 5  =>TONE <=1197;CODE<=5;HIGH<='0';
      WHEN 6  =>TONE <=1290;CODE<=6;HIGH<='0';
      WHEN 7  =>TONE <=1372;CODE<=7;HIGH<='0';
      WHEN 8  =>TONE <=1410;CODE<=1;HIGH<='1';
      WHEN 9  =>TONE <=1480;CODE<=2;HIGH<='1';
      WHEN 10  =>TONE <=1542;CODE<=3;HIGH<='1';
      WHEN 11  =>TONE <=1590;CODE<=4;HIGH<='1';
      WHEN 12  =>TONE <=1622;CODE<=5;HIGH<='1';
      WHEN 13  =>TONE <=1668;CODE<=6;HIGH<='1';
      WHEN 14  =>TONE <=1692;CODE<=7;HIGH<='1';
      WHEN 15  =>TONE <=1728;CODE<=1;HIGH<='1';
      WHEN OTHERS => NULL;
    END CASE;
  END PROCESS;
END;