library ieee;use ieee.std_logic_1164.all;library work;    package Constants is      	constant number_of_rows : natural := 6;	constant number_of_cols : natural  := 12;	constant scancode_width : natural  := 8;	constant max_keys_pressed : natural  := 3;	constant number_of_keys : natural  := number_of_rows * number_of_cols;	-- internal clock of 50 Mhz divided by 512 gives about 100 kHz, 1 clock-cycle is about 10 us	-- 100 ticks is about 1 ms.	constant debounce_count : natural  := 100;		subtype row is std_logic_vector(number_of_cols-1 downto 0);	subtype col is std_logic_vector(number_of_rows-1 downto 0);	--3 bits	subtype col_number is natural range 0 to number_of_rows-1;	--4 bits	subtype row_number is natural range 0 to number_of_cols-1;	--number of keys pressed	subtype key_number is natural range 0 to max_keys_pressed ;		subtype states is std_logic_vector(6 downto 0);      --last bit is to differentiate between idle and storing_stage2   	--output-lines : strobe, sample, analyse, store, produce, release	constant idle : states := "0000000";	constant strobing : states := "1000000";	constant sampling : states := "0100000";	constant analysing : states := "0110000";	constant storing : states := "0001000";	constant storing_stage2 : states := "0000001";	constant producenormal : states := "0000100";	constant producerelease : states := "0000110";		type keymap is array (number_of_rows-1 downto 0) of row;	subtype scancode is std_logic_vector(scancode_width-1 downto 0);	-- we need 4 bits to encode the columns and 3 bits for the rows, gives an address of 7 bits	-- that makes 128 possibilities of which 70 are used 	type set1_scancodes_lut_type is array (0 to 93) of std_logic_vector(scancode_width-1 downto 0);	constant set1_scancodes_lut : set1_scancodes_lut_type :=	(0 => X"01", --esc	1 => X"10", --q	2 => X"1e", --a	3 => X"2a", --lshi	4 => X"33", --,<	5 => X"1d", --ctrl	8 => X"3b", --f1	9 => X"11", --w	10 => X"1f", --s	11 => X"2c", --z	12 => X"1c", --enter	13 => X"38", --alt	16 => X"3c", --f2	17 => X"12", --e	18 => X"20", --d	19 => X"2d", --x	20 => X"48", --up	21 => X"39", --space	24 => X"3d", --f3	25 => X"13", --r	26 => X"21", --f	27 => X"2e", --c	28 => X"50", --down	32 => X"3e", --f4	33 => X"14", --t	34 => X"22", --g	35 => X"2f", --v	36 => X"4b", --left	40 => X"3f", --f5	41 => X"15", --y	42 => X"23", --h	43 => X"30", --b	44 => X"4d", --right	45 => X"39", --space	48 => X"28", --'"	49 => X"16", --u	50 => X"24", --j	51 => X"31", --n	53 => X"0f", --tab	56 => X"1a", --[{	57 => X"17", --i	58 => X"25", --k	59 => X"32", --m	60 => X"34", --.>	61 => X"3a", --caps		64 => X"1b", --]}	65 => X"18", --o	66 => X"26", --l	67 => X"36", --rshi	68 => X"0e", --backspace	69 => X"27", --;:	72 => X"0c", ---_	73 => X"19", --p	74 => X"08", --7&	75 => X"05", --4$	76 => X"52", --ins	77 => X"02", --1!	80 => X"0d", --=+	81 => X"29", --`~	82 => X"09", --8*	83 => X"06", --5%	84 => X"0b", --0)	85 => X"03", --2@	88 => X"2b", --\|	89 => X"35", --/?	90 => X"0a", --9(	91 => X"07", --6^	92 => X"53", --del	93 => X"04", --3#	others => X"00" --error	);end Constants;