--Angepasst von: https://github.com/Johnnyjax/vga-kbd-terminal

 library ieee;
use ieee.std_logic_1164.all;
use ieee.numeric_std.all;

entity vga_text is
port(
clk, output_mode : in std_ulogic;
key_code : in std_ulogic_vector(6 downto 0);
video_on : in std_ulogic;
pixel_x, pixel_y : in std_ulogic_vector(9 downto 0);
enter_tick : in std_ulogic;
up_tick, down_tick , left_tick, right_tick : in std_ulogic;
bck_spc_tick : in std_ulogic;
we : in std_ulogic;
text_rgb : out std_ulogic_vector(2 downto 0)
);
end vga_text;

architecture arch of vga_text is
signal char_addr : std_ulogic_vector(6 downto 0);
signal rom_addr : std_ulogic_vector(10 downto 0);
signal row_addr : std_ulogic_vector(3 downto 0);
signal bit_addr : unsigned(2 downto 0);
signal font_word : std_ulogic_vector(7 downto 0);
signal font_word2 : std_ulogic_vector(7 downto 0);
signal font_bit : std_ulogic;

signal addr_r, addr_w : std_ulogic_vector(11 downto 0);
signal din, dout : std_ulogic_vector(6 downto 0);

constant MAX_X : integer := 80;
constant MAX_Y : integer := 30;
signal we_wth_bck : std_ulogic;
signal cur_x_reg, cur_x_next : unsigned(6 downto 0);
signal cur_y_reg, cur_y_next : unsigned(4 downto 0);
signal move_x_tick, move_y_tick : std_ulogic;
signal cursor_on : std_ulogic;
signal pix_x1_reg, pix_y1_reg : unsigned(9 downto 0);
signal pix_x2_reg, pix_y2_reg : unsigned(9 downto 0);

signal bck_spc : std_ulogic;
signal font_rgb, font_rev_rgb : std_ulogic_vector(2 downto 0);


begin

font_unit : entity work.morsecode_rom
port map(clk => clk,addr => rom_addr, data => font_word);

font_unit2: entity work.font_rom
port map(clk => clk,addr => rom_addr, data2 => font_word2);


video_ram : entity work.altera_dual_port_ram_sync
generic map(ADDR_WIDTH => 12,
DATA_WIDTH => 7)

port map(clk => clk,
we => we_wth_bck,
addr_a => addr_w,
addr_b => addr_r,
din_a => din,
dout_a => open,
dout_b => dout);


process(clk)
begin
if(clk'event and clk = '1') then
cur_x_reg <= cur_x_next;
cur_y_reg <= cur_y_next;
pix_x1_reg <= unsigned(pixel_x);
pix_x2_reg <= pix_x1_reg;
pix_y1_reg <= unsigned(pixel_y);
pix_y2_reg <= pix_y1_reg;
bck_spc <= bck_spc_tick;
end if;


end process;


we_wth_bck <= we or bck_spc;
addr_w <= std_ulogic_vector(cur_y_reg & cur_x_reg);
din <= (others => '0') when bck_spc = '1' else key_code;
addr_r <= pixel_y(8 downto 4) & pixel_x(9 downto 3);
char_addr <= dout;
row_addr <= pixel_y(3 downto 0);
rom_addr <= char_addr & row_addr;
bit_addr <= pix_x2_reg(2 downto 0);

cur_x_next <= (others => '0') when ((we = '1' or right_tick = '1') and
cur_x_reg = MAX_X-1) or enter_tick = '1' or
(cur_x_reg = 0 and cur_y_reg = 0 and bck_spc_tick = '1')else
cur_x_reg + 1 when we = '1' or right_tick = '1' else
"1001111" when ((left_tick = '1' or bck_spc_tick = '1') and cur_x_reg = 0) else
cur_x_reg - 1 when left_tick = '1' or bck_spc_tick = '1' else
cur_x_reg;

cur_y_next <=
(others => '0') when (down_tick = '1' and
cur_y_reg = MAX_Y-1) or (cur_x_reg = 0 and cur_y_reg = 0 and bck_spc_tick = '1') else
"11101" when up_tick = '1' and cur_y_reg = 0 else
cur_y_reg + 1 when enter_tick = '1' or down_tick = '1' or (we = '1' and cur_x_reg = MAX_X -1) else
cur_y_reg - 1 when up_tick = '1' or (bck_spc_tick = '1' and cur_x_reg = 0) else
cur_y_reg;

font_rgb <= "000" when font_bit = '1' else "111";
font_rev_rgb <= "000" when font_bit = '1' else "010";
cursor_on <= '1' when pix_y2_reg(8 downto 4) = cur_y_reg and pix_y2_reg(3 downto 0) >= "1110" and
pix_x2_reg(9 downto 3) = cur_x_reg else '0';

process(video_on, cursor_on, font_rgb, font_rev_rgb, output_mode, font_bit, bit_addr, font_word, font_word2)
begin
if video_on = '0' then
   text_rgb <= "000";
else
   if cursor_on = '1' then
      text_rgb <= font_rev_rgb;
   else
      text_rgb <= font_rgb;
      if output_mode = '1' then            -- Wechsel zwischen Ausgabe als Morsezeichen oder Buchstaben
         font_bit <= font_word2(to_integer(not bit_addr));
      else
         font_bit <= font_word(to_integer(not bit_addr));
      end if;
   end if;
end if;
end process;
end arch;

--Angepasst von: https://github.com/Johnnyjax/vga-kbd-terminal

 

-- Listing 13.1
-- ROM with synchonous read (inferring Block RAM)
-- character ROM
-- - 8-by-16 (8-by-2^4) font
-- - 128 (2^7) characters
-- - ROM size: 512-by-8 (2^11-by-8) bits
-- 16K bits: 1 BRAM

library ieee;
use ieee.std_logic_1164.all;
use ieee.numeric_std.all;
entity morsecode_rom is
port(
clk: in std_ulogic;
addr: in std_ulogic_vector(10 downto 0);
data: out std_ulogic_vector(7 downto 0)
);
end morsecode_rom;

architecture arch of morsecode_rom is
constant ADDR_WIDTH: integer:=11;
constant DATA_WIDTH: integer:=8;
signal data_reg: std_ulogic_vector(DATA_WIDTH-1 downto 0);
type rom_type is array (0 to 2**ADDR_WIDTH-1)
of std_ulogic_vector(DATA_WIDTH-1 downto 0);
-- ROM definition
constant ROM: rom_type:=( -- 2^11-by-8

 ...

 

-- code x41 (A)
"00011000", -- 0
"00011000", -- 1
"00000000", -- 2
"00000000", -- 3
"01111110", -- 4
"00000000", -- 5
"00000000", -- 6
"00000000", -- 7
"00000000", -- 8
"00000000", -- 9
"00000000", -- a
"00000000", -- b
"00000000", -- c
"00000000", -- d
"00000000", -- e
"00000000", -- f
-- code x42 (B)
"01111110", -- 0
"00000000", -- 1
"00000000", -- 2
"00011000", -- 3
"00011000", -- 4
"00000000", -- 5
"00000000", -- 6
"00011000", -- 7
"00011000", -- 8
"00000000", -- 9
"00000000", -- a
"00011000", -- b
"00011000", -- c
"00000000", -- d
"00000000", -- e
"00000000", -- f
-- code x43 (C)
"01111110", -- 0
"00000000", -- 1
"00000000", -- 2
"00011000", -- 3
"00011000", -- 4
"00000000", -- 5
"00000000", -- 6
"01111110", -- 7
"00000000", -- 8
"00000000", -- 9
"00011000", -- a
"00011000", -- b
"00000000", -- c
"00000000", -- d
"00000000", -- e
"00000000", -- f
-- code x44 (D)
"01111110", -- 0
"00000000", -- 1
"00000000", -- 2
"00011000", -- 3
"00011000", -- 4
"00000000", -- 5
"00000000", -- 6
"00011000", -- 7
"00011000", -- 8
"00000000", -- 9
"00000000", -- a
"00000000", -- b
"00000000", -- c
"00000000", -- d
"00000000", -- e
"00000000", -- f

...