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--keyboard.vhd keyboard scanner 
library ieee ; 
use ieee.std_logic_1164.all; 
use work.components.all ; 
entity keyboard is 
port( 
  clock : in std_logic ; 
  col : in std_logic_vector(3 downto 0 ) ; 
  row : out std_logic_vector(3 downto 0) ; 
  scan_f : out std_logic ; 
  key_valid : out std_logic ; 
  butt_code : out std_logic_vector(3 downto 0)) ; 
end keyboard; 
architecture behavior of keyboard is 
  signal scanf : std_logic ; 
  signal key_pressed : std_logic ; 
  signal scan_cnt : std_logic_vector(3 downto 0) ; 
begin  
  divfreq: scan_gen 
  generic map ( osc_f => 3686 , osc_bit => 12 ) 
    port map ( clock, scanf ) ; 
  keycount: scan_count  
	port map ( clock, scanf, key_pressed, scan_cnt ) ; 
  keyscan: key_scan  
	port map ( col, scan_cnt, row, key_pressed ) ; 
  debounkey: debounce  
	port map ( key_pressed, clock, scanf, key_valid ) ; 
  coding: code_tran  
	port map ( scan_cnt, clock, butt_code ) ; 
  scan_f <= scanf ; 
end behavior;