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Honored ContributorLCD DE2-115 Initialization poblem
Hello everyone!! I'm trying to initialize LCD in the DE2-115 board. I know that the LCD is based in HDD44780U and I have following the datasheet to initialize it but the LCD turns crazy.
See my Initiazitaion code:
LIBRARY ieee;
USE ieee.std_logic_1164.ALL;
ENTITY lcd IS
PORT(
clock_50 : IN STD_LOGIC;
reset_n : IN STD_LOGIC;
lcd_enable : IN STD_LOGIC;
lcd_bus : IN STD_LOGIC_VECTOR(9 DOWNTO 0); -- DATOS Y CONTROL
busy : OUT STD_LOGIC := '1'; -- LIBRE/OCUPADO
lcd_rw, lcd_rs, lcd_en : OUT STD_LOGIC; --read/write, setup/data y ENABLE
lcd_on: out std_logic:='1';
-- lcd_blon: out std_logic:='1';
lcd_data : OUT STD_LOGIC_VECTOR(7 DOWNTO 0)); -- DATOS HACIA LCD
END lcd;
ARCHITECTURE controller OF lcd IS
TYPE CONTROL IS(power_up, initialize, ready, send);
SIGNAL state : CONTROL;
CONSTANT freq : INTEGER := 50; -- 50 Mhz
BEGIN
PROCESS(clock_50)
VARIABLE clk_count : INTEGER := 0; --Contador de timming
BEGIN
IF(clock_50'EVENT and clock_50 = '1') THEN
CASE state IS
-- Espera de 50 ms para inicilización de Vcc
WHEN power_up =>
busy <= '1';
IF(clk_count < (50000 * freq)) THEN --espera de 50 ms
clk_count := clk_count + 1;
state <= power_up;
ELSE --power-up completado
clk_count := 0;
lcd_rs <= '0';
lcd_rw <= '0';
lcd_data <= "00110000";
state <= initialize;
END IF;
-- Inicialización de LCD
WHEN initialize =>
busy <= '1';
clk_count := clk_count + 1;
IF(clk_count < (40 * freq)) THEN -- espera de 10us
lcd_data <= "00111100"; --2-line mode, display on
--lcd_data <= "00110100"; --1-line mode, display on
--lcd_data <= "00110000"; --1-line mdoe, display off
--lcd_data <= "00111000"; --2-line mode, display off
lcd_en <= '1';
state <= initialize;
-- ELSIF(clk_count < (50 * freq)) THEN --espera de 50 us
-- lcd_data <= "00000000";
-- lcd_en <= '0';
-- state <= initialize;
ELSIF(clk_count < (80 * freq)) and (clk_count > (40 * freq)) THEN --display on/off control
-- lcd_data <= "00001100"; --display on, cursor off, parpadeo off
-- lcd_data <= "00001101"; --display on, cursor off, parpadeo on
-- lcd_data <= "00001110"; --display on, cursor on, parpadeo off
lcd_data <= "00001111"; --display on, cursor on, parpadeo on
--lcd_data <= "00001000"; --display off, cursor off, parpadeo off
--lcd_data <= "00001001"; --display off, cursor off, parpadeo on
--lcd_data <= "00001010"; --display off, cursor on, parpadeo off
--lcd_data <= "00001011"; --display off, cursor on, parpadeo on
lcd_en <= '1';
state <= initialize;
-- ELSIF(clk_count < (120 * freq)) THEN --espera 50 us
-- lcd_data <= "00000000";
-- lcd_en <= '0';
-- state <= initialize;
ELSIF (clk_count > (80 * freq)) and (clk_count < (1610 * freq)) THEN -- limpiado de pantalla
lcd_data <= "00000001";
lcd_en <= '1';
state <= initialize;
-- ELSIF(clk_count < (1620 * freq)) THEN --espera 2 ms
-- lcd_data <= "00000000";
-- lcd_en <= '0';
-- state <= initialize;
ELSIF(clk_count < (1650 * freq)) and (clk_count > (1610 * freq)) THEN --entry mode set // espera 10 us
lcd_data <= "00000110"; --increment mode, entire shift off
--lcd_data <= "00000111"; --increment mode, entire shift on
--lcd_data <= "00000100"; --decrement mode, entire shift off
--lcd_data <= "00000101"; --decrement mode, entire shift on
lcd_en <= '1';
state <= initialize;
ELSIF(clk_count < (2200 * freq)) THEN --wait 60 us
lcd_data <= "00000000";
lcd_en <= '0';
state <= initialize;
ELSE --inicialización completada
clk_count := 0;
busy <= '0';
state <= ready;
END IF;
-- Espera al enable para el correcto envio de datos
WHEN ready =>
IF(lcd_enable = '1') THEN
busy <= '1';
lcd_rs <= lcd_bus(9);
lcd_rw <= lcd_bus(8);
lcd_data <= lcd_bus(7 DOWNTO 0);
clk_count := 0;
state <= send;
ELSE
busy <= '0';
lcd_rs <= '0';
lcd_rw <= '0';
lcd_data <= "00000000";
clk_count := 0;
state <= ready;
END IF;
--send instruction to lcd
WHEN send =>
busy <= '1';
IF(clk_count < (35 * freq)) THEN --do not exit for 50us
busy <= '1';
IF(clk_count < 3*freq) THEN --negative enable
lcd_en <= '0';
ELSIF(clk_count < (8 * freq)) THEN --positive enable half-cycle
lcd_en <= '1';
ELSIF(clk_count < (34* freq)) THEN --negative enable half-cycle
lcd_en <= '0';
END IF;
clk_count := clk_count + 1;
state <= send;
ELSE
clk_count := 0;
state <= ready;
END IF;
END CASE;
--reset
IF(reset_n = '0') THEN
state <= power_up;
END IF;
END IF;
END PROCESS;
END controller;
LIBRARY ieee;
USE ieee.std_logic_1164.all;
ENTITY lcd_example IS
PORT(
clock_50 : IN STD_LOGIC;
lcd_rw, lcd_rs, lcd_en : OUT STD_LOGIC;
lcd_on: out std_logic:='1';
-- lcd_blon: out std_logic:='1';
lcd_data : OUT STD_LOGIC_VECTOR(7 DOWNTO 0)
);
END lcd_example;
ARCHITECTURE behavior OF lcd_example IS
SIGNAL lcd_enable : STD_LOGIC;
SIGNAL lcd_bus : STD_LOGIC_VECTOR(9 DOWNTO 0);
SIGNAL lcd_busy : STD_LOGIC;
COMPONENT lcd IS
PORT(
clock_50 : IN STD_LOGIC;
reset_n : IN STD_LOGIC;
lcd_enable : IN STD_LOGIC;
lcd_bus : IN STD_LOGIC_VECTOR(9 DOWNTO 0);
busy : OUT STD_LOGIC;
lcd_rw, lcd_rs, lcd_en : OUT STD_LOGIC;
lcd_on: out std_logic:='1';
lcd_blon: out std_logic:='1';
lcd_data : OUT STD_LOGIC_VECTOR(7 DOWNTO 0));
END COMPONENT;
BEGIN
--Instanciación
dut: lcd
PORT MAP(clock_50=> clock_50, reset_n => '1', lcd_enable => lcd_enable, lcd_bus => lcd_bus,
busy => lcd_busy, lcd_rw => lcd_rw, lcd_rs => lcd_rs, lcd_en => lcd_en, lcd_on=>lcd_on, lcd_data => lcd_data);
PROCESS(clock_50)
VARIABLE char : INTEGER RANGE 0 TO 10 := 0;
BEGIN
IF(clock_50'EVENT AND clock_50 = '1') THEN
IF(lcd_busy = '0' AND lcd_enable = '0') THEN
lcd_enable <= '1';
IF(char < 10) THEN
char := char + 1;
END IF;
CASE char IS
WHEN 1 => lcd_bus <= "1000110001";
WHEN 2 => lcd_bus <= "1000110010";
WHEN 3 => lcd_bus <= "1000110011";
WHEN 4 => lcd_bus <= "1000110100";
WHEN 5 => lcd_bus <= "1000110101";
WHEN 6 => lcd_bus <= "1000110110";
WHEN 7 => lcd_bus <= "1000110111";
WHEN 8 => lcd_bus <= "1000111000";
WHEN 9 => lcd_bus <= "1000111001";
WHEN OTHERS => lcd_enable <= '0';
END CASE;
ELSE
lcd_enable <= '0';
END IF;
END IF;
END PROCESS;
END behavior;
