How to use String in VHDL or Verilog.

Whenever you want to use VHDL (or Verilog) code to send text to the UART or LCD, you must write the text in hexadecimal format. I thought it was very annoying. So, I was looking for an answer that could save my patience. However, everything I have found is no different in any way.

I could not bear it. So I tried to convert the text of an ASCII string into a hexadecimal array automatically, like this :
Refer to line #123

	library IEEE;
	use IEEE.STD_LOGIC_1164.all;
	use IEEE.STD_LOGIC_ARITH.all;
	use IEEE.STD_LOGIC_UNSIGNED.all;
	USE IEEE.NUMERIC_STD.ALL;
	entity LCD1602 is
	port (
	CLK : in std_logic;
	Reset : in std_logic;
	LCD_RS : out std_logic;
	LCD_RW : out std_logic;
	LCD_EN : out std_logic;
	LCD_Data : out std_logic_vector(7 downto 0)
	);
	end LCD1602;
	architecture Behavioral of LCD1602 is
	type state is (set_dlnf, set_cursor, set_dcb, set_cgram, write_cgram, set_ddram, write_LCD_Data);
	signal Current_State : state;
	type ram1 is array(0 to 30) of std_logic_vector(7 downto 0);
	type ram2 is array(0 to 30) of std_logic_vector(7 downto 0);
	type ram3 is array(0 to 30) of std_logic_vector(7 downto 0);
	constant cgram1 : ram1 := (x"46", x"50", x"47", x"41", x"2f", x"43", x"50", x"4c", x"44", x"2f", x"4D", x"43", x"55", x"20", x"20", x"20", x"57", x"57", x"57", x"2e", x"32", x"31", x"45", x"44", x"41", x"2e", x"43", x"4f", x"4d", x"20", x"20");
	constant cgram3 : ram3 := (x"68", x"74", x"74", x"70", x"3a", x"2f", x"2f", x"73", x"68", x"6F", x"70", x"33", x"35", x"31", x"38", x"31", x"33", x"30", x"37", x"2E", x"74", x"61", x"6F", x"62", x"61", x"6F", x"2E", x"63", x"6f", x"6d", x"2f");
	constant cgram2 : ram2 := (x"51", x"51", x"3a", x"39", x"30", x"36", x"36", x"30", x"36", x"35", x"39", x"36", x"20", x"20", x"20", x"20", x"54", x"65", x"6c", x"3a", x"31", x"35", x"38", x"31", x"35", x"35", x"31", x"39", x"30", x"37", x"31");
	signal CLK1 : std_logic;
	signal Clk_Out : std_logic;
	signal LCD_Clk : std_logic;
	signal m : std_logic_vector(1 downto 0);
	constant msgtext1 : string := "1234567---Aprilviva! ";
	constant msgtext2 : string := "Hello from Aprilviva! ";
	constant msgtext3 : string := "We will rock you! ";
	-- function ConvUARTData(v: character) return std_logic_vector(7 downto 0) is
	-- variable ud : integer(9 DOWNTO 0) := (OTHERS => '0');
	-- variable ch : integer(7 DOWNTO 0) := (OTHERS => '0');
	-- begin
	-- ch := to_integer(character'pos(v), 8);
	-- return ud;
	-- end ConvUARTData;
	begin
	LCD_EN <= Clk_Out;
	LCD_RW <= '0';
	process (CLK)
	variable n1 : integer range 0 to 19999;
	begin
	if rising_edge(CLK) then
	if n1 < 19999 then
	n1 := n1 + 1;
	else
	n1 := 0;
	Clk_Out <= not Clk_Out;
	end if;
	end if;
	end process;
	LCD_Clk <= Clk_Out;
	process (Clk_Out)
	variable n2 : integer range 0 to 499;
	begin
	if rising_edge(Clk_Out) then
	if n2 < 499 then
	n2 := n2 + 1;
	else
	n2 := 0;
	Clk1 <= not Clk1;
	end if;
	end if;
	end process;
	process (Clk1)
	variable n3 : integer range 0 to 14;
	begin
	if rising_edge(Clk1) then
	n3 := n3 + 1;
	if n3 <= 4 then
	m <= "00";
	elsif n3 <= 9 and n3 > 4 then
	m <= "01";
	else
	m <= "10";
	end if;
	end if;
	end process;
	process (LCD_Clk, Reset, Current_State)
	variable cnt1 : std_logic_vector(4 downto 0);
	begin
	if Reset = '0' then
	Current_State <= set_dlnf;
	cnt1 := "11110";
	LCD_RS <= '0';
	elsif rising_edge(LCD_Clk) then
	--Current_State <= Current_State;
	LCD_RS <= '0';
	case Current_State is
	when set_dlnf =>
	cnt1 := "00000";
	LCD_Data <= "00000001";
	Current_State <= set_cursor;
	when set_cursor =>
	LCD_Data <= "00111000";
	Current_State <= set_dcb;
	when set_dcb =>
	LCD_Data <= "00001100";
	Current_State <= set_cgram;
	when set_cgram =>
	LCD_Data <= "00000110";
	Current_State <= write_cgram;
	when write_cgram =>
	LCD_RS <= '1';
	if m = "00" then
	--LCD_Data <= cgram1(conv_integer(cnt1)));
	--LCD_Data <= msgtext1(conv_integer(cnt1)+1);
	LCD_Data <= conv_std_logic_vector(character'pos(msgtext1(conv_integer(cnt1)+1)), 8);
	elsif m = "01"then
	-- LCD_Data <= cgram2(conv_integer(cnt1));
	LCD_Data <= conv_std_logic_vector(character'pos(msgtext2(conv_integer(cnt1)+1)), 8);
	else
	-- LCD_Data <= cgram3(conv_integer(cnt1));
	LCD_Data <= conv_std_logic_vector(character'pos(msgtext3(conv_integer(cnt1)+1)), 8);
	end if;
	Current_State <= set_ddram;
	when set_ddram =>
	if cnt1 < "11110" then
	cnt1 := cnt1 + 1;
	else
	cnt1 := "00000";
	end if;
	if cnt1 <= "01111" then
	LCD_Data <= "10000000" + cnt1;--80H
	else
	LCD_Data <= "11000000" + cnt1 - "10000";--80H
	end if;
	Current_State <= write_LCD_Data;
	when write_LCD_Data =>
	LCD_Data <= "00000000";
	Current_State <= set_cursor;
	when others => null;
	end case;
	end if;
	end process;
	end Behavioral;

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