- Proc_Scan:process(Clk_5ms)
- begin
- if(rising_edge(Clk_5ms)) then
- case Current_Scan is
- when st_scan1 =>
- Key_Scan <= "1110";
- Current_Scan <= st_scan2;
- when st_scan2 =>
- Key_Scan <= "1101";
- Current_Scan <= st_scan3;
- when st_scan3 =>
- Key_Scan <= "1011";
- Current_Scan <= st_scan4;
- when st_scan4 =>
- Key_Scan <= "0111";
- Current_Scan <= st_scan1;
- end case;
- end if;
- end process Proc_Scan;
- KeyScan <= Key_Scan;
- Key_Decode <= Key_Scan & Keyin;
- Proc_Keyboard:process(Clk_2ms,Reset)
- variable cnt_btn : integer range 0 to 50000 := 0;
- begin
- if(Reset = '1') then
- LED <= x"1";
- Current_Key <= st_key1;
- elsif(falling_edge(Clk_2ms)) then
- case Current_Key is
- when st_key1 => --Check whether any keys are pressed
- if((Keyin and "1111") = "1111") then
- Current_Key <= st_key1;
- else
- Current_Key <= st_key2;
- end if;
- when st_key2 => --keys debouncing
- if((Keyin and "1111") = "1111") then
- Current_Key <= st_key1;
- else
- case Key_Decode is
- when "11101110" => LED <= "0001";
- when "11101101" => LED <= "0010";
- when "11101011" => LED <= "0011";
- when "11100111" => LED <= "1010";
- when "11011110" => LED <= "0100";
- when "11011101" => LED <= "0101";
- when "11011011" => LED <= "0110";
- when "11010111" => LED <= "1011";
- when "10111110" => LED <= "0111";
- when "10111101" => LED <= "1000";
- when "10111011" => LED <= "1001";
- when "10110111" => LED <= "1100";
- when "01111110" => LED <= "1110";
- when "01111101" => LED <= "0000";
- when "01111011" => LED <= "1111";
- when "01110111" => LED <= "1101"; when others => null;
- end case;
- end if;
- Current_Key <= st_key3;
- when st_key3 => --Check whether the pressed keys are released
- if((Keyin and "1111") /= "1111") then
- Current_Key <= st_key3;
- else
- Current_Key <= st_key4;
- end if;
- when st_key4 => --keys debouncing
- if((Keyin and "1111") /= "1111") then
- Current_Key <= st_key3;
- else
- LED <= x"0";
- Current_Key <= st_key1;
- end if;
- end case;
- end if;
- end process Proc_Keyboard;
- end Behavioral;
|
