VHDL code position: p83_ex4_11_DFF1
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--LIBARY IEEE;
--USE IEEE.STD_LOGIC_1164.ALL;
ENTITY DFF1 IS
PORT ( CLK : IN BIT;
D : IN BIT;
Q : OUT BIT
);
END ENTITY DFF1;
ARCHITECTURE bhv OF DFF1 IS
BEGIN
PROCESS(CLK)
BEGIN
IF CLK'EVENT AND (CLK='1') AND ( CLK'LAST_VALUE = '0') THEN
-- 严格的CLK信号上升沿定义
Q <= D;
END IF;
END PROCESS;
END ARCHITECTURE bhv;