---------------------------------------------------------------------------
-- (c) 2013 mark watson
-- I am happy for anyone to use this for non-commercial use.
-- If my vhdl files are used commercially or otherwise sold,
-- please contact me for explicit permission at scrameta (gmail).
-- This applies for source and binary form and derived works.
---------------------------------------------------------------------------

---------------------------------------------------------------------------
-- (ILoveSpeccy) Added PS2_KEYS Output
---------------------------------------------------------------------------

LIBRARY ieee;
USE ieee.std_logic_1164.all;
use ieee.numeric_std.all;


ENTITY ps2_to_atari5200 IS
PORT 
( 
	CLK : IN STD_LOGIC;
	RESET_N : IN STD_LOGIC;
	PS2_CLK : IN STD_LOGIC;
	PS2_DAT : IN STD_LOGIC;
	
	KEYBOARD_SCAN : IN STD_LOGIC_VECTOR(5 downto 0);
	KEYBOARD_RESPONSE : OUT STD_LOGIC_VECTOR(1 downto 0);

	FIRE2 : IN STD_LOGIC_VECTOR(3 downto 0);
	CONTROLLER_SELECT : IN STD_LOGIC_VECTOR(1 downto 0);

	FKEYS : OUT STD_LOGIC_VECTOR(11 downto 0);

	FREEZER_ACTIVATE : OUT STD_LOGIC;
   
	PS2_KEYS : OUT STD_LOGIC_VECTOR(511 downto 0)
);
END ps2_to_atari5200;

ARCHITECTURE vhdl OF ps2_to_atari5200 IS
	signal ps2_keys_next : std_logic_vector(511 downto 0);
	signal ps2_keys_reg : std_logic_vector(511 downto 0);

	signal key_event : std_logic;
	signal key_value : std_logic_vector(7 downto 0);
	signal key_extended : std_logic;
	signal key_up : std_logic;

	signal FKEYS_INT : std_logic_vector(11 downto 0);

	signal FREEZER_ACTIVATE_INT : std_logic;

	signal atari_keyboard : std_logic_vector(15 downto 0);

	signal fire_pressed_sel : std_logic;
BEGIN

   PS2_KEYS <= ps2_keys_reg;

	keyboard1: entity work.ps2_keyboard
	PORT MAP
	( 
		CLK => CLK,
		RESET_N => RESET_N,
		PS2_CLK => PS2_CLK,
		PS2_DAT => PS2_DAT,
		
		KEY_EVENT => KEY_EVENT,
		KEY_VALUE => KEY_VALUE,
		KEY_EXTENDED => KEY_EXTENDED,
		KEY_UP => KEY_UP
--		KEY_EVENT : OUT STD_LOGIC; -- high for 1 cycle on new key pressed(or repeated)/released
--		KEY_VALUE : OUT STD_LOGIC_VECTOR(7 downto 0); -- valid on event, raw scan code
--		KEY_EXTENDED : OUT STD_LOGIC;           -- valid on event, if scan code extended
--		KEY_UP : OUT STD_LOGIC                 -- value on event, if key released
	);

	process(clk,reset_n)
	begin
		if (reset_n='0') then
			ps2_keys_reg <= (others=>'0');
		elsif (clk'event and clk='1') then
			ps2_keys_reg <= ps2_keys_next;
		end if;
	end process;

	-- 1 bit per PS2 key
	process(KEY_EVENT, KEY_VALUE, KEY_EXTENDED, KEY_UP, ps2_keys_reg)
	begin
		ps2_keys_next <= ps2_keys_reg;

		if (key_event = '1') then
			ps2_keys_next(to_integer(unsigned(KEY_EXTENDED&KEY_VALUE))) <= NOT(KEY_UP);
		end if;
	end process;

	-- map to atari key code
	process(ps2_keys_reg, fire2, controller_select)
	begin
		atari_keyboard <= (others=>'0');

		fire_pressed_sel <= '0';

		case controller_select is
		when "00" =>
			-- todo change order to match keycode! check with petes test
			atari_keyboard(12)<=ps2_keys_reg(16#05#); --f1
			atari_keyboard(8)<=ps2_keys_reg(16#06#); --f2
			atari_keyboard(4)<=ps2_keys_reg(16#04#); --f3
			atari_keyboard(15)<=ps2_keys_reg(16#16#); --1
			atari_keyboard(14)<=ps2_keys_reg(16#1E#); --2
			atari_keyboard(13)<=ps2_keys_reg(16#26#); --3
			atari_keyboard(11)<=ps2_keys_reg(16#15#); --q
			atari_keyboard(10)<=ps2_keys_reg(16#1D#); --w
			atari_keyboard(9)<=ps2_keys_reg(16#24#); --e
			atari_keyboard(7)<=ps2_keys_reg(16#1c#);   --a
			atari_keyboard(6)<=ps2_keys_reg(16#1b#);  --s
			atari_keyboard(5)<=ps2_keys_reg(16#23#);  --d
			atari_keyboard(3)<=ps2_keys_reg(16#1a#);  --z 
			atari_keyboard(2)<=ps2_keys_reg(16#22#);  --x
			atari_keyboard(1)<=ps2_keys_reg(16#21#);  --c
			fire_pressed_sel <= fire2(0);
		when "01" =>
			atari_keyboard(12)<=ps2_keys_reg(16#29#);
			atari_keyboard(8)<=ps2_keys_reg(16#29#);
			atari_keyboard(4)<=ps2_keys_reg(16#29#);
			atari_keyboard(15)<=ps2_keys_reg(16#29#);
			atari_keyboard(14)<=ps2_keys_reg(16#29#);
			atari_keyboard(13)<=ps2_keys_reg(16#29#);
			atari_keyboard(11)<=ps2_keys_reg(16#29#);
			atari_keyboard(10)<=ps2_keys_reg(16#29#);
			atari_keyboard(9)<=ps2_keys_reg(16#29#);
			atari_keyboard(7)<=ps2_keys_reg(16#29#);
			atari_keyboard(6)<=ps2_keys_reg(16#29#);
			atari_keyboard(5)<=ps2_keys_reg(16#29#);
			atari_keyboard(3)<=ps2_keys_reg(16#29#);
			atari_keyboard(2)<=ps2_keys_reg(16#29#);
			atari_keyboard(1)<=ps2_keys_reg(16#29#);
			fire_pressed_sel <= fire2(1);
		when "10" =>
			atari_keyboard(12)<=ps2_keys_reg(16#29#);
			atari_keyboard(8)<=ps2_keys_reg(16#29#);
			atari_keyboard(4)<=ps2_keys_reg(16#29#);
			atari_keyboard(15)<=ps2_keys_reg(16#29#);
			atari_keyboard(14)<=ps2_keys_reg(16#29#);
			atari_keyboard(13)<=ps2_keys_reg(16#29#);
			atari_keyboard(11)<=ps2_keys_reg(16#29#);
			atari_keyboard(10)<=ps2_keys_reg(16#29#);
			atari_keyboard(9)<=ps2_keys_reg(16#29#);
			atari_keyboard(7)<=ps2_keys_reg(16#29#);
			atari_keyboard(6)<=ps2_keys_reg(16#29#);
			atari_keyboard(5)<=ps2_keys_reg(16#29#);
			atari_keyboard(3)<=ps2_keys_reg(16#29#);
			atari_keyboard(2)<=ps2_keys_reg(16#29#);
			atari_keyboard(1)<=ps2_keys_reg(16#29#);
			fire_pressed_sel <= fire2(2);
		when "11" =>
			atari_keyboard(12)<=ps2_keys_reg(16#29#);
			atari_keyboard(8)<=ps2_keys_reg(16#29#);
			atari_keyboard(4)<=ps2_keys_reg(16#29#);
			atari_keyboard(15)<=ps2_keys_reg(16#29#);
			atari_keyboard(14)<=ps2_keys_reg(16#29#);
			atari_keyboard(13)<=ps2_keys_reg(16#29#);
			atari_keyboard(11)<=ps2_keys_reg(16#29#);
			atari_keyboard(10)<=ps2_keys_reg(16#29#);
			atari_keyboard(9)<=ps2_keys_reg(16#29#);
			atari_keyboard(7)<=ps2_keys_reg(16#29#);
			atari_keyboard(6)<=ps2_keys_reg(16#29#);
			atari_keyboard(5)<=ps2_keys_reg(16#29#);
			atari_keyboard(3)<=ps2_keys_reg(16#29#);
			atari_keyboard(2)<=ps2_keys_reg(16#29#);
			atari_keyboard(1)<=ps2_keys_reg(16#29#);
			fire_pressed_sel <= fire2(3);
		when others =>
		end case;

		fkeys_int(0)<=ps2_keys_reg(16#05#);
		fkeys_int(1)<=ps2_keys_reg(16#06#);
		fkeys_int(2)<=ps2_keys_reg(16#04#);
		fkeys_int(3)<=ps2_keys_reg(16#0C#);
		fkeys_int(4)<=ps2_keys_reg(16#03#);
		fkeys_int(5)<=ps2_keys_reg(16#0B#);
		fkeys_int(6)<=ps2_keys_reg(16#83#);
		fkeys_int(7)<=ps2_keys_reg(16#0a#);
		fkeys_int(8)<=ps2_keys_reg(16#01#);
		fkeys_int(9)<=ps2_keys_reg(16#09#);
		fkeys_int(10)<=ps2_keys_reg(16#78#);
		fkeys_int(11)<=ps2_keys_reg(16#07#);

		-- use scroll lock or delete to activate freezer (same key on my keyboard + scroll lock does not seem to work on mist!)
		freezer_activate_int <= ps2_keys_reg(16#7e#) or ps2_keys_reg(16#171#);
	end process;

	-- provide results as if we were a grid to pokey...
	process(keyboard_scan, atari_keyboard, fire_pressed_sel)
		begin	
			keyboard_response <= (others=>'1');		
			
			if (atari_keyboard(to_integer(unsigned(not(keyboard_scan(4 downto 1))))) = '1') then
				keyboard_response(0) <= '0';
			end if;
			
			keyboard_response(1) <= not(fire_pressed_sel);
	end process;		 

	-- outputs
	FKEYS <= FKEYS_INT;
	FREEZER_ACTIVATE <= FREEZER_ACTIVATE_INT;
END vhdl;