为什么gamma_cor_array_s类不是常量? GAMMA_COR
与DEPH
类似,不需要触发器,编写一个函数来初始化gamma_cor_s的使用位置,而不使用实体/体系结构对。
正如gamma_cor_s的值是(0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15)
rising_edge(CLK)后:
library ieee;
use ieee.std_logic_1164.all;
use work.mytypes.all; -- type gamma_cor_array
entity gam_cor_tb is
end entity;
architecture foo of gam_cor_tb is
signal clk: std_logic := '0';
constant DEPH: natural := 4;
constant GAMMA_COR: real := 1.0;
signal gamma_cor_array_s:
gamma_cor_array (2 ** DEPH - 1 downto 0) ;
begin
CLOCK:
process
begin
wait for 10 ns;
clk <= not clk;
wait for 10 ns;
wait; -- one ping only
end process;
DUT:
entity work.gamma_correction
generic map (
DEPH => DEPH,
GAMMA_COR => GAMMA_COR
)
port map (
clk => clk,
gamma_cor_array_s => gamma_cor_array_s
);
MONITOR:
process (gamma_cor_array_s)
begin
for i in 0 to (2 ** DEPH - 1) loop
report "gamma_cor_array_s(" & integer'image(i) & ") = " &
integer'image(gamma_cor_array_s(i));
end loop;
end process;
end architecture;
结果:
gamma_corrections.vhdl:75:13:@ 0毫秒:(报告注): gamma_cor_array_s(0) = 0 gamma_corrections.vhdl:75:13:0ms:(报告注释):gamma_cor_array_s(1)= 0 gamma_corrections.vhdl:75:13:0ms:(报告 注释):gamma_cor_array_s(2) = 0 gamma_corrections.vhdl:75:13:@ 0ms :(报告注释):gamma_cor_array_s(3 (报告附注):gamma_cor_array_s(4)= 0 gamma_corrections.vhdl:75:13:0ms:(报告 注):gamma_cor_array_s(5)= 0 gamma_corrections.vhdl:75:13:0ms:(报告附注):gamma_cor_array_s(6) = 0 gamma_corrections.vhdl:75:13:0ms:(报告附注):gamma_cor_array_s(7)= 0 gamma_corrections.vhdl:75 (报告说明):gamma_cor_array_s(9) = 0 gamma_corrections.vhdl:75:13:0ms:(报告 note):gamma_cor_array_s(8)= 0 gamma_corrections.vhdl:75:13: @ 0ms :(报告注释):gamma_cor_array_s(10)= 0 gamma_corrections.vhdl:75:13:@ 0ms :(报告 注释):gamma_cor_array_s(11)= 0 gamma_corrections。vhdl:75:13:0ms:(报告附注):gamma_cor_array_s(12) = 0 gamma_corrections.vhdl:75:13:0ms:(报告附注):gamma_cor_array_s(13)= 0 gamma_corrections.vhdl:75:13 :@ 0ms :(报告 注):gamma_cor_array_s(14)= 0 gamma_corrections.vhdl:75:13:0ms:(报告注释):gamma_cor_array_s(15) = 0 gamma_corrections.vhdl:75:13:@ 10ns :报告注释:gamma_cor_array_s(0)= 0 gamma_corrections.vhdl:75:13:@ 10ns :(报告 注释):gamma_cor_array_s(1)= 1 gamma_corrections.vhdl:75:13:@ 10ns: ):gamma_cor_array_s(2) = 2 gamma_corrections.vhdl:75:13:10ns :(报告注释):gamma_cor_array_s(3)= 3 gamma_corrections.vhdl:75:13:@ 10ns :(报告 注释):gamma_cor_array_s( 4)= 4 gamma_corrections.vhdl:75:13:@ 10ns :(报告说明):gamma gamma_cor_array_s(5) = 5 gamma_corrections.vhdl:75:13:@ 10ns :(报告注释):gamma_cor_array_s(6)= 6 gamma_corrections.vhdl:75:13:@ 10ns :(报告 注释):gamma_cor_array_s(7) (报告注释):gamma_cor_array_s(8) = 8 gamma_corrections.vhdl:75:13:10ns :(报告注释):gamma_cor_array_s(9)= 9 gamma_corrections。 (报告注释): gamma_cor_array_s(11)= 11 gamma_corrections.vhdl:75(vhdl:75:13:@ 10ns)(报告 注意):gamma_cor_array_s(10)= 10 gamma_corrections.vhdl:75:13: :13:@ 10ns :(报告 注释):gamma_cor_array_s(12)= 12 gamma_corrections.vhdl:75:13:@ 10ns :(报告注释): gamma_cor_array_s(13)= 13 gamma_corrections.vhdl:75:13: @ 10ns :(报告 注):gamma_cor_array_s(14)= 14 gamma_corrections.vhdl:75:13:@ 10ns的:(报告注释): gamma_cor_array_s(15)= 15
您申报64个人字拖,他们初始化所有'0',只有30个变为'1' - 你没有显示所有的警告(这里可以忽略)。使用real类型是不可移植的(实际值是近似的)。
对实体gamma_correction上下文条款应该是:不需要
library ieee;
ieee.std_logic_1164.all; -- for type std_logic, function rising_edge
use ieee.math_real.all; -- for function "**" [integer, real return real]
use work.mytypes.all; -- for type gamma_cor_array
到新跃大学的引用。
用于初始化常数,而不是使用在一个独立的实体和架构产生的信号:
architecture fum of gam_cor_tb is
signal clk: std_logic := '0';
constant DEPH: natural := 4;
constant GAMMA_COR: real := 1.0;
-- signal gamma_cor_array_s:
-- gamma_cor_array (2 ** DEPH - 1 downto 0) ;
function gamma_correct return gamma_cor_array is -- added pure function
use ieee.math_real.all;
variable gamma_cor_array_s: gamma_cor_array(2 ** DEPH - 1 downto 0);
begin
for i in 0 to (2 ** DEPH - 1) loop
gamma_cor_array_s(i) := integer (
((real(i)/real (2 ** DEPH - 1)) ** GAMMA_COR) *
real(2 ** DEPH - 1)
);
end loop;
return gamma_cor_array_s;
end function;
constant gamma_cor_array_s: -- previously a signal
gamma_cor_array (2 ** DEPH - 1 downto 0) := gamma_correct;
begin
-- CLOCK:
-- process
-- begin
-- wait for 10 ns;
-- clk <= not clk;
-- wait for 10 ns;
-- wait; -- one ping only
-- end process;
-- DUT:
-- entity work.gamma_correction
-- generic map (
-- DEPH => DEPH,
-- GAMMA_COR => GAMMA_COR
-- )
-- port map (
-- clk => clk,
-- gamma_cor_array_s => gamma_cor_array_s
-- );
MONITOR:
process -- (gamma_cor_array_s)
begin
for i in 0 to (2 ** DEPH - 1) loop
report "gamma_cor_array_s(" & integer'image(i) & ") = " &
integer'image(gamma_cor_array_s(i));
end loop;
wait;
end process;
end architecture;
功能规范需要是先前作为通用常量实体gamma_correction传递常数的范围内。
该函数用于初始化一个常数,该常数是查找表以确定伽马校正。
注意,没有信号在基于事件的进程之间传递值。你为gamma_cor_array_s分配的值从未改变(实体gamma_correction体系结构中的进程中的驱动程序)。
的输出值是:
gamma_corrections.vhdl:126:13:@ 0毫秒:(报告注):gamma_cor_array_s(0) = 0 gamma_corrections.vhdl:126:13:@ 0毫秒:(报告注释):gamma_cor_array_s(1)= 1 gamma_corrections.vhdl:126:13:0ms:(报告 注释):gamma_cor_array_s(2)= 2 gamma_corrections.vhdl:126:13:0ms(报告注释): gamma_cor_array_s(3) = 3 gamma_corrections。vhdl:126:13:@ 0ms :(报告注释):gamma_cor_array_s(4)= 4 gamma_corrections.vhdl:126:13:0ms:(报告 注释):gamma_cor_array_s(5)= 5 gamma_corrections.vhdl:126: 13:@ 0ms :(报告注释):gamma_cor_array_s(6) = 6 gamma_corrections.vhdl:126:13:0ms:(报告注释):gamma_cor_array_s(7)= 7 gamma_corrections.vhdl:126:13:0ms: (report report note):gamma_cor_array_s(8)= 8 gamma_corrections.vhdl:126:13:0ms:(report report):gamma_cor_array_s(9) = 9 gamma_corrections.vhdl:126:13:0ms:(report report ):gamma_cor_array_s(10)= 10 gamma_corrections.vhdl:126:13:0ms:(报告 note):gamma_cor_array_s(11)= 11 gamma_corrections.vhdl:126:13:0ms:(报告说明): gamma_cor_array_s (12)= 12 gamma_corrections.vhdl:126:13:0ms:(报告 注释):gamma_cor_array_s(13)= 13 gamma_corrections.vhdl:126:13:@ 0毫秒:(报告注): gamma_cor_array_s(14)= 14 gamma_corrections.vhdl:126:13:@ 0毫秒:(报告 注释) :gamma_cor_array_s(15)= 15
它与在时钟的上升沿之后的先前信号的值匹配。
这有可能使gamma_cor_array_s的信号,进行动态分配,这需要所有的作业都是在一个过程中完成的(并行语句将制定一个过程的分配)
谢谢你的建议。你帮了我很多。我会推荐你的网站给我所有的朋友... –
[良好的问题](https://stackoverflow.com/help/how-to-ask)可以吸引很好的答案。结果不仅仅是一个问题和答案。他们可以为那些有相同或类似问题的人提供资源。 – user1155120