wallywall
Newbie level 3
hello i am trying to finish my keypad encoder project. i ill be using Quartus II for simulation and the Altera DE2 board for testing. below is my vhdl code. i am stuck at defining my inputs and outputs in Quartus. Also i am stuck when it comes to assigning pins to the DE2 board. PLEASE HELP!!
Code:
LIBRARY ieee;
USE ieee.std_logic_1164.all ;
ENTITY keyencoder IS
PORT ( clk :IN STD_LOGIC;
col :IN STD_LOGIC_VECTOR (3 DOWNTO 0) ;
row :OUT STD_LOGIC_VECTOR (3 DOWNTO 0) ;
d :OUT STD_LOGIC_VECTOR (3 DOWNTO 0) ;
dav :OUT STD_LOGIC );
END keyencoder;
ARCHITECTURE vhdl OF keyencoder IS
SIGNAL Freeze :STD_LOGIC;
SIGNAL data :STD_LOGIC_VECTOR (3 DOWNTO 0);
BEGIN
PROCESS (clk)
VARIABLE ring :STD_LOGIC_VECTOR (3DOWNTO 0) ;
BEGIN
IF (clk'EVENT AND clk = '1') THEN
IF freeze = '0' THEN
CASE ring IS
WHEN "1110" => ring := "1101";
WHEN "1101" => ring := "1011";
WHEN "1011" => ring := "0111";
WHEN "0111" => ring := "1110";
WHEN OTHERS => ring := "1110";
END CASE;
END IF;
dav <= freeze;
END IF;
row <= ring;
CASE ring IS
WHEN "1110" => data(3 DOWNTO 2) <= "00";
WHEN "1101" => data(3 DOWNTO 2) <= "01";
WHEN "1011" => data(3 DOWNTO 2) <= "10";
WHEN "0111" => data(3 DOWNTO 2) <= "11";
WHEN OTHERS => data(3 DOWNTO 2) <= "00";
END CASE;
CASE col IS
WHEN "1110" => data(1 DOWNTO 0) <= "00"; freeze <= '1';
WHEN "1101" => data(1 DOWNTO 0) <= "01"; freeze <= '1';
WHEN "1011" => data(1 DOWNTO 0) <= "10"; freeze <= '1';
WHEN "0111" => data(1 DOWNTO 0) <= "11"; freeze <= '1';
WHEN OTHERS => data(1 DOWNTO 0) <= "00"; freeze <= '0';
END CASE;
IF freeze = '1' THEN d <= data;
ELSE d <= "ZZZZ" ;
END IF;
END PROCESS;
END vhdl;