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Shift-Register Design:Delay error

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tri2061990

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My Code
library ieee;

use ieee.std_logic_1164.all;
use ieee.std_logic_arith.all;
use ieee.std_logic_unsigned.all;

entity b11 is
port(shin:in std_logic_vector(7 downto 0);
reset:in std_logic;
enable:in std_logic;
clock : in std_logic;
shout:eek:ut std_logic_vector(7 downto 0));
end b11;


architecture a of b11 is
begin

xuly:process(clock,enable,reset)
begin
if reset ='1' then
shout<=(others=>'0');
elsif clock='1' and clock'event then
if enable='1' then
shout<=shin(3 downto 0)&"0000";
else
shout<=shin;
end if;
end if;
end process xuly;

end a;

My error
My output is delayed :when input is loaded at the rising of clock pulse and enable signal ='1' then output appear after one period
I'm sorry my English is not good
 

FvM

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It's unclear what you want to achieve, the code is not describing a shift register. shout is loaded on each clock cycle, there's no "one period" delay. It may seem like this according to your test case.
 

FvM

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You are releasing reset simultaneously with the first clock edge, thus this edge is ignored.
 

tri2061990

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I fixed it
thank you!
 
Last edited:

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