Altera推荐的带异步清零，使能的D触发器的写法

module dff_control(clk, aclr, aload, ena, data, adata, q);
input clk, aclr, aload, ena, data, adata;
output q;
reg q;
always @ (posedge clk or posedge aclr or posedge aload)
begin
if (aclr)
q <= 1'b0;
else if (aload)
q <= adata;
else if (ena)
q <= data;
end
endmodul

LIBRARY ieee;
USE ieee.std_logic_1164.all;
ENTITY dff_control IS
PORT (
clk: IN STD_LOGIC;
aclr: IN STD_LOGIC;
aload: IN STD_LOGIC;
adata: IN STD_LOGIC;
ena: IN STD_LOGIC;
data: IN STD_LOGIC;
q: OUT STD_LOGIC
);
END dff_control;

ARCHITECTURE rtl OF dff_control IS
BEGIN
PROCESS (clk, aclr, aload, adata)
BEGIN
IF (aclr = '1') THEN
q <= '0';
ELSIF (aload = '1') THEN
q <= adata;
ELSE
IF (clk = '1' AND clk'event) THEN
IF (ena ='1') THEN
q <= data;
END IF;
END IF;
END IF;
END PROCESS;
END rtl;

Altera推荐的带异步清零，使能的D触发器的写法

Altera推荐的带异步清零，使能的D触发器的写法

不错，写的很好

谢谢查看！！！！！！！

谢谢楼主分享，受教了！

Altera推荐的带异步清零，使能的D触发器的写法

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