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发表于 2013-6-26 14:04:21
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- LIBRARY IEEE;
- USE IEEE.STD_LOGIC_1164.all;
- USE IEEE.STD_LOGIC_ARITH.all;
- USE IEEE.STD_LOGIC_UNSIGNED.all;
- -- This code displays time in the DE2's LCD Display
- -- Key2 resets time
- ENTITY DE2_CLOCK IS
- PORT(reset, clk_50Mhz : IN STD_LOGIC;
- LCD_RS, LCD_E, LCD_ON, RESET_LED, SEC_LED : OUT STD_LOGIC;
- LCD_RW : BUFFER STD_LOGIC;
- DATA_BUS : INOUT STD_LOGIC_VECTOR(7 DOWNTO 0));
- END DE2_CLOCK;
-
- ARCHITECTURE a OF DE2_CLOCK IS
- TYPE STATE_TYPE IS (HOLD, FUNC_SET, DISPLAY_ON, MODE_SET, WRITE_CHAR1,
- WRITE_CHAR2,WRITE_CHAR3,WRITE_CHAR4,WRITE_CHAR5,WRITE_CHAR6,WRITE_CHAR7,
- WRITE_CHAR8, WRITE_CHAR9, WRITE_CHAR10, RETURN_HOME, TOGGLE_E, RESET1, RESET2,
- RESET3, DISPLAY_OFF, DISPLAY_CLEAR);
- SIGNAL state, next_command: STATE_TYPE;
- SIGNAL DATA_BUS_VALUE: STD_LOGIC_VECTOR(7 DOWNTO 0);
- SIGNAL CLK_COUNT_400HZ: STD_LOGIC_VECTOR(19 DOWNTO 0);
- SIGNAL CLK_COUNT_10HZ: STD_LOGIC_VECTOR(7 DOWNTO 0);
- SIGNAL BCD_SECD0,BCD_SECD1,BCD_MIND0,BCD_MIND1: STD_LOGIC_VECTOR(3 DOWNTO 0);
- SIGNAL BCD_HRD0,BCD_HRD1,BCD_TSEC: STD_LOGIC_VECTOR(3 DOWNTO 0);
- SIGNAL CLK_400HZ, CLK_10HZ : STD_LOGIC;
- BEGIN
- LCD_ON <= '1';
- RESET_LED <= NOT RESET;
- SEC_LED <= BCD_SECD0(0);
- -- BIDIRECTIONAL TRI STATE LCD DATA BUS
- DATA_BUS <= DATA_BUS_VALUE WHEN LCD_RW = '0' ELSE "ZZZZZZZZ";
-
- PROCESS
- BEGIN
- WAIT UNTIL CLK_50MHZ'EVENT AND CLK_50MHZ = '1';
- IF RESET = '0' THEN
- CLK_COUNT_400HZ <= X"00000";
- CLK_400HZ <= '0';
- ELSE
- IF CLK_COUNT_400HZ < X"0F424" THEN
- CLK_COUNT_400HZ <= CLK_COUNT_400HZ + 1;
- ELSE
- CLK_COUNT_400HZ <= X"00000";
- CLK_400HZ <= NOT CLK_400HZ;
- END IF;
- END IF;
- END PROCESS;
- PROCESS (CLK_400HZ, reset)
- BEGIN
- IF reset = '0' THEN
- state <= RESET1;
- DATA_BUS_VALUE <= X"38";
- next_command <= RESET2;
- LCD_E <= '1';
- LCD_RS <= '0';
- LCD_RW <= '0';
-
- ELSIF CLK_400HZ'EVENT AND CLK_400HZ = '1' THEN
- -- GENERATE 1/10 SEC CLOCK SIGNAL FOR SECOND COUNT PROCESS
- IF CLK_COUNT_10HZ < 19 THEN
- CLK_COUNT_10HZ <= CLK_COUNT_10HZ + 1;
- ELSE
- CLK_COUNT_10HZ <= X"00";
- CLK_10HZ <= NOT CLK_10HZ;
- END IF;
- -- SEND TIME TO LCD
- CASE state IS
- -- Set Function to 8-bit transfer and 2 line display with 5x8 Font size
- -- see Hitachi HD44780 family data sheet for LCD command and timing details
- WHEN RESET1 =>
- LCD_E <= '1';
- LCD_RS <= '0';
- LCD_RW <= '0';
- DATA_BUS_VALUE <= X"38";
- state <= TOGGLE_E;
- next_command <= RESET2;
- WHEN RESET2 =>
- LCD_E <= '1';
- LCD_RS <= '0';
- LCD_RW <= '0';
- DATA_BUS_VALUE <= X"38";
- state <= TOGGLE_E;
- next_command <= RESET3;
- WHEN RESET3 =>
- LCD_E <= '1';
- LCD_RS <= '0';
- LCD_RW <= '0';
- DATA_BUS_VALUE <= X"38";
- state <= TOGGLE_E;
- next_command <= FUNC_SET;
- -- EXTRA STATES ABOVE ARE NEEDED FOR RELIABLE PUSHBUTTON RESET OF LCD
- WHEN FUNC_SET =>
- LCD_E <= '1';
- LCD_RS <= '0';
- LCD_RW <= '0';
- DATA_BUS_VALUE <= X"38";
- state <= TOGGLE_E;
- next_command <= DISPLAY_OFF;
- -- Turn off Display and Turn off cursor
- WHEN DISPLAY_OFF =>
- LCD_E <= '1';
- LCD_RS <= '0';
- LCD_RW <= '0';
- DATA_BUS_VALUE <= X"08";
- state <= TOGGLE_E;
- next_command <= DISPLAY_CLEAR;
- -- Turn on Display and Turn off cursor
- WHEN DISPLAY_CLEAR =>
- LCD_E <= '1';
- LCD_RS <= '0';
- LCD_RW <= '0';
- DATA_BUS_VALUE <= X"01";
- state <= TOGGLE_E;
- next_command <= DISPLAY_ON;
- -- Turn on Display and Turn off cursor
- WHEN DISPLAY_ON =>
- LCD_E <= '1';
- LCD_RS <= '0';
- LCD_RW <= '0';
- DATA_BUS_VALUE <= X"0C";
- state <= TOGGLE_E;
- next_command <= MODE_SET;
- -- Set write mode to auto increment address and move cursor to the right
- WHEN MODE_SET =>
- LCD_E <= '1';
- LCD_RS <= '0';
- LCD_RW <= '0';
- DATA_BUS_VALUE <= X"06";
- state <= TOGGLE_E;
- next_command <= WRITE_CHAR1;
- -- Write ASCII hex character in first LCD character location
- WHEN WRITE_CHAR1 =>
- LCD_E <= '1';
- LCD_RS <= '1';
- LCD_RW <= '0';
- DATA_BUS_VALUE <= X"3" & BCD_HRD1;
- state <= TOGGLE_E;
- next_command <= WRITE_CHAR2;
- -- Write ASCII hex character in second LCD character location
- WHEN WRITE_CHAR2 =>
- LCD_E <= '1';
- LCD_RS <= '1';
- LCD_RW <= '0';
- DATA_BUS_VALUE <= X"3" & BCD_HRD0;
- state <= TOGGLE_E;
- next_command <= WRITE_CHAR3;
- -- Write ASCII hex character in third LCD character location
- WHEN WRITE_CHAR3 =>
- LCD_E <= '1';
- LCD_RS <= '1';
- LCD_RW <= '0';
- DATA_BUS_VALUE <= X"3A" ;
- state <= TOGGLE_E;
- next_command <= WRITE_CHAR4;
- -- Write ASCII hex character in fourth LCD character location
- WHEN WRITE_CHAR4 =>
- LCD_E <= '1';
- LCD_RS <= '1';
- LCD_RW <= '0';
- DATA_BUS_VALUE <= X"3" & BCD_MIND1;
- state <= TOGGLE_E;
- next_command <= WRITE_CHAR5;
- -- Write ASCII hex character in fifth LCD character location
- WHEN WRITE_CHAR5 =>
- LCD_E <= '1';
- LCD_RS <= '1';
- LCD_RW <= '0';
- DATA_BUS_VALUE <= X"3" & BCD_MIND0;
- state <= TOGGLE_E;
- next_command <= WRITE_CHAR6;
- -- Write ASCII hex character in sixth LCD character location
- WHEN WRITE_CHAR6 =>
- LCD_E <= '1';
- LCD_RS <= '1';
- LCD_RW <= '0';
- DATA_BUS_VALUE <= X"3A" ;
- state <= TOGGLE_E;
- next_command <= WRITE_CHAR7;
- -- Write ASCII hex character in seventh LCD character location
- WHEN WRITE_CHAR7 =>
- LCD_E <= '1';
- LCD_RS <= '1';
- LCD_RW <= '0';
- DATA_BUS_VALUE <= X"3" & BCD_SECD1;
- state <= TOGGLE_E;
- next_command <= WRITE_CHAR8;
- -- Write ASCII hex character in eighth LCD character location
- WHEN WRITE_CHAR8 =>
- LCD_E <= '1';
- LCD_RS <= '1';
- LCD_RW <= '0';
- DATA_BUS_VALUE <= X"3" & BCD_SECD0;
- state <= TOGGLE_E;
- next_command <= WRITE_CHAR9;
- WHEN WRITE_CHAR9 =>
- LCD_E <= '1';
- LCD_RS <= '1';
- LCD_RW <= '0';
- DATA_BUS_VALUE <= X"2E";
- state <= TOGGLE_E;
- next_command <= WRITE_CHAR10;
- WHEN WRITE_CHAR10 =>
- LCD_E <= '1';
- LCD_RS <= '1';
- LCD_RW <= '0';
- DATA_BUS_VALUE <= X"3" & BCD_TSEC;
- state <= TOGGLE_E;
- next_command <= RETURN_HOME;
-
- -- Return write address to first character postion
- WHEN RETURN_HOME =>
- LCD_E <= '1';
- LCD_RS <= '0';
- LCD_RW <= '0';
- DATA_BUS_VALUE <= X"80";
- state <= TOGGLE_E;
- next_command <= WRITE_CHAR1;
- -- The next two states occur at the end of each command to the LCD
- -- Toggle E line - falling edge loads inst/data to LCD controller
- WHEN TOGGLE_E =>
- LCD_E <= '0';
- state <= HOLD;
- -- Hold LCD inst/data valid after falling edge of E line
- WHEN HOLD =>
- state <= next_command;
- END CASE;
- END IF;
- END PROCESS;
- PROCESS (Clk_10hz, reset)
- BEGIN
- IF reset = '0' THEN
- BCD_HRD1 <= X"0";
- BCD_HRD0 <= X"0";
- BCD_MIND1 <= X"0";
- BCD_MIND0 <= X"0";
- BCD_SECD1 <= X"0";
- BCD_SECD0 <= X"0";
- BCD_TSEC <= X"0";
-
- ELSIF clk_10HZ'EVENT AND clk_10HZ = '1' THEN
- -- TENTHS OF SECONDS
- IF BCD_TSEC < 9 THEN
- BCD_TSEC <= BCD_TSEC + 1;
- ELSE
- BCD_TSEC <= X"0";
- -- SECONDS
- IF BCD_SECD0 < 9 THEN
- BCD_SECD0 <= BCD_SECD0 + 1;
- ELSE
- -- TENS OF SECONDS
- BCD_SECD0 <= "0000";
- IF BCD_SECD1 < 5 THEN
- BCD_SECD1 <= BCD_SECD1 + 1;
- ELSE
- -- MINUTES
- BCD_SECD1 <= "0000";
- IF BCD_MIND0 < 9 THEN
- BCD_MIND0 <= BCD_MIND0 + 1;
- ELSE
- -- TENS OF MINUTES
- BCD_MIND0 <= "0000";
- IF BCD_MIND1 < 5 THEN
- BCD_MIND1 <= BCD_MIND1 + 1;
- ELSE
- -- HOURS
- BCD_MIND1 <= "0000";
- IF BCD_HRD0 < 9 AND NOT((BCD_HRD1 = 2) AND (BCD_HRD0 = 3))THEN
- BCD_HRD0 <= BCD_HRD0 + 1;
- ELSE
- -- TENS OF HOURS
- IF NOT((BCD_HRD1 = 2) AND (BCD_HRD0 = 3)) THEN
- BCD_HRD1 <= BCD_HRD1 + 1;
- BCD_HRD0 <= "0000";
- ELSE
- -- NEW DAY
- BCD_HRD1 <= "0000";
- BCD_HRD0 <= "0000";
- END IF;
- END IF;
- END IF;
- END IF;
- END IF;
- END IF;
- END IF;
- END IF;
- END PROCESS;
- END a;
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