百度作业网纯小白在写作业,可是map过不去?报错啊.求助! xilinx,ISE
来源：学生作业帮 编辑：百度作业网作业帮 分类：综合作业 时间：2024/05/09 18:40:43
写期末作业,很简单的键盘译码.但是在map中过不去,貌似是键盘扫描程序有问题.贴在下面了,下面还有report,问题简单,大家不要笑,麻烦指出错误,谢谢!为什么被删了那么多信号呢?report中.
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;
ENTITY KEY_SCAN IS
PORT (
clk : IN std_logic:='0';
row : IN std_logic_vector(3 DOWNTO 0):="1111"; -- 键盘行向量
press : OUT std_logic:='0';
column : BUFFER std_logic_vector(3 DOWNTO 0); -- 输出列向量
code : BUFFER std_logic_vector(3 DOWNTO 0):="ZZZZ" -- 键盘编码0~f
);
END KEY_SCAN;
ARCHITECTURE Behavioral OF KEY_SCAN IS
SIGNAL clk_scan : std_logic;
SIGNAL code_old : std_logic_vector(3 DOWNTO 0):="ZZZZ";
SIGNAL cnt_key : integer range 1 to 8;
BEGIN
process(clk)
variable tt: integer:=0;
begin
tt:=tt+1;
if(tt=9) then tt:=1; end if;
cnt_key<=tt;
end process;
process(clk,cnt_key)
begin
if(cnt_key<5)then
clk_scan<='1';
else
clk_scan<='0';
end if;
end process;
process(clk_scan)
variable t: integer:=0;
begin
if(clk_scan'EVENT and clk_scan='1')then
case t is
when 0=>column<="1110";
when 1=>column<="1101";
when 2=>column<="1011";
when 3=>column<="0111";
when others=>null;
end case;
t:=t+1;
if(t=4) then t:=0; end if;
end if;
end process;
process(clk)
begin
if(cnt_key>1 and cnt_key<5)then
case column is
when "1110" =>
case row is
when "1110" =>code<= "0000";
when "1101" =>code<= "0001";
when "1011" =>code<= "0010";
when "0111" =>code<= "0011";
when OTHERS =>code<= "ZZZZ";
end case;
省略一部分译码
when OTHERS =>code<= "ZZZZ";
end case;
when OTHERS =>code<= "ZZZZ";
end case;
else
code<= "ZZZZ";
end if;
if(cnt_key=4) then
code_old<=code;
end if;
end process;
process(clk)
begin
if(code_old/=code and code/="ZZZZ") then
if(cnt_key=3) then
press<='1';
else
press<='0';
end if;
else
press<='0';
end if;
end process;
END Behavioral;
这是report.
Section 1 - Errors
------------------
ERROR:MapLib:661 - LUT3 symbol "XLXI_4/_n0046131" (output signal=CHOICE875) has
input signal "XLXI_4/_n0034" which will be trimmed. See the trim report for
details about why the input signal will become undriven.
省略
Section 5 - Removed Logic
The signal "XLXI_4/t<1>" is unused and has been removed.
The signal "XLXI_4/code_old<2>" is unused and has been removed.
The signal "XLXI_4/code_old<0>" is unused and has been removed.
The signal "XLXI_4/key_scan__n0007<4>_cyo" is unused and has been removed.
省略
