沈阳工程学院课程设计（论文）
WHEN 104 => ToneIndex <= 9; WHEN 105 => ToneIndex <= 9; WHEN 106 => ToneIndex <= 10; WHEN 107 => ToneIndex <= 9; WHEN 108 => ToneIndex <= 8; WHEN 109 => ToneIndex <= 8; WHEN 110 => ToneIndex <= 6; WHEN 111 => ToneIndex <= 5; WHEN 112 => ToneIndex <= 3; WHEN 113 => ToneIndex <= 3; WHEN 114 => ToneIndex <= 3; WHEN 115 => ToneIndex <= 3; WHEN 116 => ToneIndex <= 8; WHEN 117 => ToneIndex <= 8; WHEN 118 => ToneIndex <= 8; WHEN 119 => ToneIndex <= 8; WHEN 120 => ToneIndex <= 6; WHEN 121 => ToneIndex <= 8; WHEN 122 => ToneIndex <= 6; WHEN 123 => ToneIndex <= 5; WHEN 124 => ToneIndex <= 3; WHEN 125 => ToneIndex <= 5; WHEN 126 => ToneIndex <= 6; WHEN 127 => ToneIndex <= 8;
WHEN 128 => ToneIndex <= 5; WHEN 129 => ToneIndex <= 5; WHEN 130 => ToneIndex <= 5; WHEN 131 => ToneIndex <= 5; when 132 => ToneIndex <= 5; when 133 => ToneIndex <= 5; when 134 => ToneIndex <= 5; when 135 => ToneIndex <= 5; when 136 => ToneIndex <= 0;
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沈阳工程学院课程设计（论文）
when 137 => ToneIndex <= 0; when 138 => ToneIndex <= 0; WHEN OTHERS => NULL; END CASE; END PROCESS; END;
--------------------------------------------------------------------------------------------------------------------- 程序2 数控分频 LIBRARY IEEE;
USE IEEE.STD_LOGIC_1164.ALL; ENTITY Speakera IS
PORT ( clk : IN STD_LOGIC;
Tone : IN INTEGER RANGE 0 TO 16#1FFF#; SpkS : OUT STD_LOGIC ); END;
ARCHITECTURE one OF Speakera IS SIGNAL PreCLK : STD_LOGIC; SIGNAL FullSpkS : STD_LOGIC; BEGIN
DivideCLK : PROCESS(clk)
VARIABLE Count4 : INTEGER RANGE 0 TO 15; BEGIN
PreCLK <= '0';
-- 将CLK进行16分频，PreCLK为CLK的16分频 IF Count4 > 11 THEN PreCLK <= '1'; Count4 := 0;
ELSIF clk'EVENT AND clk = '1' THEN Count4 := Count4 + 1; END IF; END PROCESS;
GenSpkS : PROCESS(PreCLK, Tone)
VARIABLE Count13 : INTEGER RANGE 0 TO 16#1FFF#;
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沈阳工程学院课程设计（论文）
BEGIN
-- 11位可预置计数器
IF PreCLK'EVENT AND PreCLK = '1' THEN IF Count13= 16#1FFF# THEN Count13 := Tone;
FullSpkS <= '1'; ELSE
Count13 := Count13 + 1;
FullSpkS <= '0'; END IF; END IF; END PROCESS;
DelaySpkS : PROCESS(FullSpkS) VARIABLE Count2 : STD_LOGIC; BEGIN
-- 将输出再进行2分频，将脉冲展宽，以使扬声器有足够功率发音 IF FullSpkS'EVENT AND FullSpkS = '1' THEN Count2 := NOT Count2;
IF Count2 = '1' THEN SpkS <= '1';
Else SpkS<='0';END IF;
END IF; END PROCESS; END;
---------------------------------------------------------------------------------------------------------------------- 程序3 音符译码 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;
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沈阳工程学院课程设计（论文）
ARCHITECTURE one OF ToneTaba IS BEGIN
Search : PROCESS(Index) BEGIN
CASE Index IS -- 译码电路，查表方式，控制音调的预置数 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 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 12 => Tone <= 1622; CODE <= 5; HIGH <= '1'; WHEN 13 => Tone <= 1668; CODE <= 6; HIGH <= '1'; WHEN 15 => Tone <= 1728; CODE <= 7; HIGH <= '1'; WHEN OTHERS => NULL; END CASE; END PROCESS; END;
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