程序如下
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LIBRARY ieee;
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USE ieee.Std_logic_1164.ALL;
$ f& i, j e8 f2 k, k: AUSE ieee.Std_logic_unsigned.ALL;
/ m& s9 d7 W* P5 m/ Q( `ENTITY delay IS
4 ?$ [: p8 u% l8 z2 I. F* t PORT(
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clk,din: IN Std_logic;
2 Q- g6 U+ h/ P3 y9 H6 ~ dout
ut std_logic;
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Sin:in std_logic_vector(5 downto 0);
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reset:in std_logic
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4 e7 [4 ?2 z S( k* O& e0 aEND delay;
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ARCHITECTURE v1 OF delay IS
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SIGNAL int_reg:std_logic_vector(63 downto 0);
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BEGIN
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3 ~( R0 {; F: m! p. p: i) zmain_proc : PROCESS(clk,reset)
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BEGIN
6 g; [' |, V6 k8 [! @7 v" M7 n if clk='1'and clk'event then
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if reset='1'then
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int_reg<=(others=>'0');
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dout<='0';
. d( w/ ]% N! T else
! Y4 y, H. b& v f# W int_reg(0)<=din;
+ F! Y0 N( G. W$ q int_reg(63 downto 1) <= int_reg(62 downto 0);
% C5 M! x) k& a; Y& B* L2 S dout<=int_reg(conv_integer(sin));
0 k) L8 p/ W$ g# x7 X: z y end if;
& `' u' {( y# X+ I end if;
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END PROCESS;
H4 {, E5 Z5 L) i o* y% j7 \END v1;
