【设计求助】逻辑单元不够用了怎么办?

jzw1987

我用VHDL写了一个同时对三路频率进行测频的程序(采用双精度的方法),标准频率用100MHZ(用24位计数器存放),待测频率用16位计数器存放.可在程序写完之后提示逻辑单元不够用了...请问程序应该如何修改才能尽量减少逻辑单元的使用呢? (我用的是EPM7160SCL84-6).
程序如下:
library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_unsigned.all;
entity four0ut is
port(
f0,fx,fy,fz,rs,en : in std_logic;
choose: in std_logic_vector (3 downto 0);
output: out std_logic_vector (7 downto 0));
end four0ut;
architecture behave of four0ut is
signal out_fx0,out_fx1,out_fx2,out_fx3 :std_logic_vector (3 downto 0); --待测频率1计数存放
signal out_fy0,out_fy1,out_fy2,out_fy3 :std_logic_vector (3 downto 0); --待测频率2计数存放
signal out_fz0,out_fz1,out_fz2,out_fz3 :std_logic_vector (3 downto 0); --待测频率3计数存放

signal out_f00,out_f01,out_f02,out_f03,out_f04,out_f05 :std_logic_vector (3 downto 0); --待测频率1对应的标准频率计数存放
signal out_f10,out_f11,out_f12,out_f13,out_f14,out_f15 :std_logic_vector (3 downto 0); --待测频率2对应的标准频率计数存放
signal out_f20,out_f21,out_f22,out_f23,out_f24,out_f25 :std_logic_vector (3 downto 0); --待测频率3对应的标准频率计数存放

signal star1,star2,star3: std_logic;
begin
--**************以下是第一路频率的测量部分************************
process(fx,rs)
begin
if(rs='0') then
star1 <= '0';
out_fx0 <="0000"; out_fx1 <="0000"; out_fx2 <="0000"; out_fx3 <="0000";
elsif(fx' event and fx = '1') then
if(en='1') then
if (out_fx0 = 15) then out_fx0 <="0000";
if (out_fx1 = 15) then out_fx1 <="0000";
if (out_fx2 = 15) then out_fx2 <="0000";
if (out_fx3 = 15) then out_fx3 <="0000";
else out_fx3 <= out_fx3 + 1 ;
end if;
else out_fx2 <= out_fx2 + 1 ;
end if;
else out_fx1 <= out_fx1 + 1 ;
end if;
else out_fx0 <= out_fx0 + 1 ;
end if;

star1 <= '1';
elsif(star1 ='1') then
star1 <= '0';
end if;
end if;
end process;

--**********以下是第二路频率的测量部分****************************
process(fy,rs)
begin
if(rs='0') then
star2 <= '0';
out_fy0 <="0000"; out_fy1 <="0000"; out_fy2 <="0000"; out_fy3 <="0000";
elsif(fy' event and fy = '1') then
if(en='1') then
if (out_fy0 = 15) then out_fy0 <="0000";
if (out_fy1 = 15) then out_fy1 <="0000";
if (out_fy2 = 15) then out_fy2 <="0000";
if (out_fy3 = 15) then out_fy3 <="0000";
else out_fy3 <= out_fy3 + 1 ;
end if;
else out_fy2 <= out_fy2 + 1 ;
end if;
else out_fy1 <= out_fy1 + 1 ;
end if;
else out_fy0 <= out_fy0 + 1 ;
end if;
star2 <= '1';
elsif(star2 ='1') then
star2 <= '0';
end if;
end if;
end process;

--********以下是第三路频率的测量部分************************
process(fz,rs)
begin
if(rs='0') then
star3 <= '0';
out_fz0 <="0000"; out_fz1 <="0000"; out_fz2 <="0000"; out_fz3 <="0000";
elsif(fz' event and fz = '1') then
if(en='1') then
if (out_fz0 = 15) then out_fz0 <="0000";
if (out_fz1 = 15) then out_fz1 <="0000";
if (out_fz2 = 15) then out_fz2 <="0000";
if (out_fz3 = 15) then out_fz3 <="0000";
else out_fz3 <= out_fz3 + 1 ;
end if;
else out_fz2 <= out_fz2 + 1 ;
end if;
else out_fz1 <= out_fz1 + 1 ;
end if;
else out_fz0 <= out_fz0 + 1 ;
end if;
star3 <= '1';
elsif(star3 ='1') then
star3 <= '0';
end if;
end if;
end process;

--*************以下是标准频率的测量部分******************
process(f0,rs)
begin
if(rs = '0') then
out_f00 <="0000"; out_f01 <="0000"; out_f02 <="0000"; out_f03 <="0000"; out_f04 <="0000"; out_f05 <="0000";
out_f10 <="0000"; out_f11 <="0000"; out_f12 <="0000"; out_f13 <="0000"; out_f14 <="0000"; out_f15 <="0000";
out_f20 <="0000"; out_f21 <="0000"; out_f22 <="0000"; out_f23 <="0000"; out_f24 <="0000"; out_f25 <="0000";

elsif(f0' event and f0 = '1') then
if(star1 = '1') then
if (out_f00 = 15) then out_f00 <="0000";
if (out_f01 = 15) then out_f01 <="0000";
if (out_f02 = 15) then out_f02 <="0000";
if (out_f03 = 15) then out_f03 <="0000";
if (out_f04 = 15) then out_f04 <="0000";
if (out_f05 = 15) then out_f05 <="0000";
else out_f05 <= out_f05 + 1 ;
end if;
else out_f04 <= out_f04 + 1 ;
end if;
else out_f03 <= out_f03 + 1 ;
end if;
else out_f02 <= out_f02 + 1 ;
end if;
else out_f01 <= out_f01 + 1 ;
end if;
else out_f00 <= out_f00 + 1 ;
end if;
end if;
if(star2 = '1') then
if (out_f10 = 15) then out_f10 <="0000";
if (out_f11 = 15) then out_f11 <="0000";
if (out_f12 = 15) then out_f12 <="0000";
if (out_f13 = 15) then out_f13 <="0000";
if (out_f14 = 15) then out_f14 <="0000";
if (out_f15 = 15) then out_f15 <="0000";
else out_f15 <= out_f15 + 1 ;
end if;
else out_f14 <= out_f14 + 1 ;
end if;
else out_f13 <= out_f13 + 1 ;
end if;
else out_f12 <= out_f12 + 1 ;
end if;
else out_f11 <= out_f11 + 1 ;
end if;
else out_f10 <= out_f10 + 1 ;
end if;
end if;
if(star3 = '1') then
if (out_f20 = 15) then out_f20 <="0000";
if (out_f21 = 15) then out_f21 <="0000";
if (out_f22 = 15) then out_f22 <="0000";
if (out_f23 = 15) then out_f23 <="0000";
if (out_f24 = 15) then out_f24 <="0000";
if (out_f25 = 15) then out_f25 <="0000";
else out_f25 <= out_f25 + 1 ;
end if;
else out_f24 <= out_f24 + 1 ;
end if;
else out_f23 <= out_f23 + 1 ;
end if;
else out_f22 <= out_f22 + 1 ;
end if;
else out_f21 <= out_f21 + 1 ;
end if;
else out_f20 <= out_f20 + 1 ;
end if;
end if;
end if;
end process;
--***************以下是输出部分程序***********************
process(choose)
begin
case choose is
--**********以下是第一组测量结果的输出***********************************
when "0000" => output(7 downto 4) <= out_f05 ;
output(3 downto 0) <= out_f04 ;
when "0001" => output(7 downto 4) <= out_f03 ;
output(3 downto 0) <= out_f02 ;
when "0010" => output(7 downto 4) <= out_f01 ;
output(3 downto 0) <= out_f00 ;
when "0011" => output(7 downto 4) <= out_fx3 ;
output(3 downto 0) <= out_fx2 ;
when "0100" => output(7 downto 4) <= out_fx1 ;
output(3 downto 0) <= out_fx0 ;
--************以下是第二组测量结果的输出***********************************
when "0101" => output(7 downto 4) <= out_f15 ;
output(3 downto 0) <= out_f14 ;
when "0110" => output(7 downto 4) <= out_f13 ;
output(3 downto 0) <= out_f12 ;
when "0111" => output(7 downto 4) <= out_f11 ;
output(3 downto 0) <= out_f10 ;
when "1000" => output(7 downto 4) <= out_fy3 ;
output(3 downto 0) <= out_fy2 ;
when "1001" => output(7 downto 4) <= out_fy1 ;
output(3 downto 0) <= out_fy0 ;
--******以下是第三组测量结果的输出***********************************
when "1010" => output(7 downto 4) <= out_f25 ;
output(3 downto 0) <= out_f24 ;
when "1011" => output(7 downto 4) <= out_f23 ;
output(3 downto 0) <= out_f22 ;
when "1100" => output(7 downto 4) <= out_f21 ;
output(3 downto 0) <= out_f20 ;
when "1101" => output(7 downto 4) <= out_fz3 ;
output(3 downto 0) <= out_fz2 ;
when "1110" => output(7 downto 4) <= out_fz1 ;
output(3 downto 0) <= out_fz0 ;
when others => output <= "00000000";
end case;
end process;
end behave;

袈裟破

压缩一下程序或者换个大容量的片子                                                                                                                                                                       

袈裟破

如果你的代码要求的速度不是很高你可以考虑用串并转换的方法来较少面积，代价是降低运行速度。如果这已经是你能承受的最慢速度那么你只能换片子了。