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[/] [System09/] [trunk/] [rtl/] [VHDL/] [ps2_keyboard.vhd] - Diff between revs 99 and 118

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Line 10... Line 10...
--                  
--                  
--  Dependencies   : ieee.std_logic_1164
--  Dependencies   : ieee.std_logic_1164
--                   ieee.std_logic_unsigned
--                   ieee.std_logic_unsigned
--                   ieee.std_logic_arith
--                   ieee.std_logic_arith
--                   ieee.numeric_std
--                   ieee.numeric_std
--                   unisim.vcomponents
 
--
--
--  Author         : Original Verilog version by John Clayton
--  Author         : Original Verilog version by John Clayton
--                   Converted to VHDL by John E. Kent
--                   Converted to VHDL by John E. Kent
--
--
--  Email          : dilbert57@opencores.org      
--  Email          : dilbert57@opencores.org      
Line 152... Line 151...
-- 2004-10-18 Added ctrl keys to ASCII ROM
-- 2004-10-18 Added ctrl keys to ASCII ROM
--            Added CAPS Lock toggle.
--            Added CAPS Lock toggle.
-- 2007-02-06 Added Generic Clock parameter
-- 2007-02-06 Added Generic Clock parameter
-- 2010-05-31 Revised header, added GPL
-- 2010-05-31 Revised header, added GPL
-- 2010-06-17 Change some signal names for consistancy
-- 2010-06-17 Change some signal names for consistancy
--
-- 2010-10-24 Rearranged code to prevent shift key outputting characters
--
--
--
--
---------------------------------------------------------------------------------------
---------------------------------------------------------------------------------------
 
 
library ieee;
library ieee;
   use ieee.std_logic_1164.all;
   use ieee.std_logic_1164.all;
   use ieee.std_logic_arith.all;
   use ieee.std_logic_arith.all;
   use ieee.std_logic_unsigned.all;
   use ieee.std_logic_unsigned.all;
   use ieee.numeric_std.all;
   use ieee.numeric_std.all;
library unisim;
--library unisim;
   use unisim.vcomponents.all;
--   use unisim.vcomponents.all;
 
 
entity ps2_keyboard is
entity ps2_keyboard is
  generic (
  generic (
  CLK_FREQ_MHZ   : integer
  CLK_FREQ_MHZ   : integer
  );
  );
Line 201... Line 200...
constant EXTEND_CODE  : integer := 16#E0#;
constant EXTEND_CODE  : integer := 16#E0#;
constant RELEASE_CODE : integer := 16#F0#;
constant RELEASE_CODE : integer := 16#F0#;
constant LEFT_SHIFT   : integer := 16#12#;
constant LEFT_SHIFT   : integer := 16#12#;
constant RIGHT_SHIFT  : integer := 16#59#;
constant RIGHT_SHIFT  : integer := 16#59#;
constant CTRL_CODE    : integer := 16#14#;
constant CTRL_CODE    : integer := 16#14#;
 
constant LEFT_ALT     : integer := 16#11#;
constant CAPS_CODE    : integer := 16#58#;
constant CAPS_CODE    : integer := 16#58#;
 
constant SCROLL_LOCK  : integer := 16#7E#;
 
constant NUM_LOCK     : integer := 16#77#;
 
 
 
 
-- constants
-- constants
 
 
-- The timer value can be up to (2^bits) inclusive.
-- The timer value can be up to (2^bits) inclusive.
Line 226... Line 228...
--constant TIMER_60USEC_BITS_PP  : integer := 11;   -- Number of bits needed for timer
--constant TIMER_60USEC_BITS_PP  : integer := 11;   -- Number of bits needed for timer
--constant TIMER_5USEC_VALUE_PP  : integer := 125;  -- Number of sys_clks for debounce
--constant TIMER_5USEC_VALUE_PP  : integer := 125;  -- Number of sys_clks for debounce
--constant TIMER_5USEC_BITS_PP   : integer := 7;    -- Number of bits needed for timer
--constant TIMER_5USEC_BITS_PP   : integer := 7;    -- Number of bits needed for timer
 
 
-- Values for  generic Clock up to 50 MHz
-- Values for  generic Clock up to 50 MHz
constant TIMER_60USEC_VALUE_PP : integer := CLK_FREQ_MHZ * 60;  -- Number of sys_clks for 60usec.
constant TIMER_60USEC_VALUE_PP : integer := CLK_FREQ_MHZ * 60;  -- Number of clock cycles for 60usec.
constant TIMER_60USEC_BITS_PP  : integer := 12;                 -- Number of bits needed for timer
constant TIMER_60USEC_BITS_PP  : integer := 12;                 -- Number of bits needed for timer
constant TIMER_5USEC_VALUE_PP  : integer := CLK_FREQ_MHZ * 5;   -- Number of sys_clks for debounce
constant TIMER_5USEC_VALUE_PP  : integer := CLK_FREQ_MHZ * 5;   -- Number of clock cycles for debounce
constant TIMER_5USEC_BITS_PP   : integer := 8;                  -- Number of bits needed for timer
constant TIMER_5USEC_BITS_PP   : integer := 8;                  -- Number of bits needed for timer
 
 
constant TRAP_SHIFT_KEYS_PP    : integer := 1;   -- Default: No shift key trap.
constant TRAP_SHIFT_KEYS_PP    : integer := 1;   -- Default: No shift key trap.
 
 
-- State encodings, provided as constants
-- State encodings, provided as constants
Line 383... Line 385...
  tx_error                 <= '0';
  tx_error                 <= '0';
  enable_timer_60usec      <= '0';
  enable_timer_60usec      <= '0';
  enable_timer_5usec       <= '0';
  enable_timer_5usec       <= '0';
 
 
  case (m1_state) is
  case (m1_state) is
 
        --
 
        -- receive clock transitions
 
        --
  when m1_rx_clk_h =>
  when m1_rx_clk_h =>
        enable_timer_60usec <= '1';
        enable_timer_60usec <= '1';
        if (tx_write = '1') then
        if (tx_write = '1') then
                      m1_next_state <= m1_tx_reset_timer;
                      m1_next_state <= m1_tx_reset_timer;
        elsif (ps2_clk_s = '0') then
        elsif (ps2_clk_s = '0') then
Line 411... Line 416...
 
 
  when m1_rx_rising_edge_marker =>
  when m1_rx_rising_edge_marker =>
        enable_timer_60usec <= '0';
        enable_timer_60usec <= '0';
        m1_next_state <= m1_rx_clk_h;
        m1_next_state <= m1_rx_clk_h;
 
 
 
        --
 
        -- write to keyboard (Tx)
 
        --
  when m1_tx_reset_timer =>
  when m1_tx_reset_timer =>
        enable_timer_60usec <= '0';
        enable_timer_60usec <= '0';
        m1_next_state <= m1_tx_force_clk_l;
        m1_next_state <= m1_tx_force_clk_l;
 
 
  when m1_tx_force_clk_l =>
  when m1_tx_force_clk_l =>
Line 506... Line 514...
  when others =>
  when others =>
             m1_next_state <= m1_rx_clk_h;
             m1_next_state <= m1_rx_clk_h;
  end case;
  end case;
end process;
end process;
 
 
 
--
-- This is the bit counter
-- This is the bit counter
 
--
bit_counter: process(clk, reset, m1_state, bit_count )
bit_counter: process(clk, reset, m1_state, bit_count )
begin
begin
  if clk'event and clk = '0' then
  if clk'event and clk = '0' then
    if ( reset = '1' ) or
                if ( reset = '1' ) or ( rx_shifting_done = '1' ) or
       ( rx_shifting_done = '1' ) or
 
       (m1_state = m1_tx_wait_keyboard_ack) then       -- After tx is done.
       (m1_state = m1_tx_wait_keyboard_ack) then       -- After tx is done.
       bit_count <= "0000";  -- normal reset
       bit_count <= "0000";  -- normal reset
    elsif (timer_60usec_done = '1' ) and
    elsif (timer_60usec_done = '1' ) and
          (m1_state = m1_rx_clk_h)      and
          (m1_state = m1_rx_clk_h)      and
          (ps2_clk_s = '1') then
          (ps2_clk_s = '1') then
Line 523... Line 532...
    elsif (m1_state = m1_rx_falling_edge_marker) or  -- increment for rx
    elsif (m1_state = m1_rx_falling_edge_marker) or  -- increment for rx
          (m1_state = m1_tx_rising_edge_marker) then  -- increment for tx
          (m1_state = m1_tx_rising_edge_marker) then  -- increment for tx
       bit_count <= bit_count + 1;
       bit_count <= bit_count + 1;
    end if;
    end if;
  end if;
  end if;
end process;
 
 
 
assign: process( bit_count, tx_write, tx_data_empty_o, m1_state )
 
begin
 
  if (bit_count = TOTAL_BITS) then
  if (bit_count = TOTAL_BITS) then
     rx_shifting_done <= '1';
     rx_shifting_done <= '1';
  else
  else
     rx_shifting_done <= '0';
     rx_shifting_done <= '0';
  end if;
  end if;
Line 538... Line 544...
  if (bit_count = (TOTAL_BITS-1)) then
  if (bit_count = (TOTAL_BITS-1)) then
     tx_shifting_done <= '1';
     tx_shifting_done <= '1';
  else
  else
     tx_shifting_done <= '0';
     tx_shifting_done <= '0';
  end if;
  end if;
 
end process;
 
 
 
assign: process( bit_count, tx_write, m1_state, tx_data_empty_o, m1_state )
 
begin
 
        --
-- This is the signal which enables loading of the shift register.
-- This is the signal which enables loading of the shift register.
-- It also indicates "ack" to the device writing to the transmitter.
-- It also indicates "ack" to the device writing to the transmitter.
 
        --
  if ((tx_write = '1') and (m1_state = m1_rx_clk_h)) or
  if ((tx_write = '1') and (m1_state = m1_rx_clk_h)) or
     ((tx_write = '1') and (m1_state = m1_rx_clk_l)) then
     ((tx_write = '1') and (m1_state = m1_rx_clk_l)) then
     tx_data_empty_o <= '1';
     tx_data_empty_o <= '1';
  else
  else
     tx_data_empty_o <= '0';
     tx_data_empty_o <= '0';
  end if;
  end if;
  tx_data_empty <= tx_data_empty_o;
  tx_data_empty <= tx_data_empty_o;
end process;
end process;
 
 
 
-- This is the shift register
 
q_shift : process(clk, tx_data_empty_o, tx_parity_bit, tx_data,
 
                  m1_state, q, ps2_data_s, rx_shifting_done )
 
begin
 
        --
-- This is the ODD parity bit for the transmitted word.
-- This is the ODD parity bit for the transmitted word.
-- assign tx_parity_bit = ~^tx_data;
-- assign tx_parity_bit = ~^tx_data;
--
--
tx_parity_bit <= not( tx_data(7) xor tx_data(6) xor tx_data(5) xor tx_data(4) xor
tx_parity_bit <= not( tx_data(7) xor tx_data(6) xor tx_data(5) xor tx_data(4) xor
                      tx_data(3) xor tx_data(2) xor tx_data(1) xor tx_data(0) );
                      tx_data(3) xor tx_data(2) xor tx_data(1) xor tx_data(0) );
 
 
-- This is the shift register
 
q_shift : process(clk, tx_data_empty_o, tx_parity_bit, tx_data,
 
                  m1_state, q, ps2_data_s, rx_shifting_done )
 
begin
 
  if clk'event and clk='0' then
  if clk'event and clk='0' then
    if (reset = '1') then
    if (reset = '1') then
            q <= "00000000000";
                        q <= (others=>'0');
    elsif (tx_data_empty_o = '1') then
    elsif (tx_data_empty_o = '1') then
            q <= "1" & tx_parity_bit & tx_data & "0";
            q <= "1" & tx_parity_bit & tx_data & "0";
    elsif ( (m1_state = m1_rx_falling_edge_marker)      or
    elsif ( (m1_state = m1_rx_falling_edge_marker)      or
            (m1_state = m1_tx_rising_edge_marker) ) then
            (m1_state = m1_tx_rising_edge_marker) ) then
       q <= ps2_data_s & q((TOTAL_BITS-1) downto 1);
       q <= ps2_data_s & q((TOTAL_BITS-1) downto 1);
    end if;
    end if;
  end if;
  end if;
 
 
-- Create the signals which indicate special scan codes received.
 
-- These are the "unlatched versions."
 
  if (q(8 downto 1) = EXTEND_CODE) and (rx_shifting_done = '1') then
 
    extended <= '1';
 
  else
 
    extended <= '0';
 
  end if;
 
  if (q(8 downto 1) = RELEASE_CODE) and (rx_shifting_done = '1') then
 
    released <= '1';
 
  else
 
    released <= '0';
 
  end if;
 
end process;
end process;
 
 
 
--
-- This is the 60usec timer counter
-- This is the 60usec timer counter
 
--
timer60usec: process(clk, enable_timer_60usec, timer_60usec_count)
timer60usec: process(clk, enable_timer_60usec, timer_60usec_count)
begin
begin
  if clk'event and clk = '0' then
  if clk'event and clk = '0' then
    if (enable_timer_60usec = '0') then
    if (enable_timer_60usec = '0') then
            timer_60usec_count <= (others => '0');
            timer_60usec_count <= (others => '0');
Line 603... Line 605...
  else
  else
    timer_60usec_done <= '0';
    timer_60usec_done <= '0';
  end if;
  end if;
end process;
end process;
 
 
 
--
-- This is the 5usec timer counter
-- This is the 5usec timer counter
 
--
timer5usec : process(clk, enable_timer_5usec, timer_5usec_count )
timer5usec : process(clk, enable_timer_5usec, timer_5usec_count )
begin
begin
  if clk'event and clk = '0' then
  if clk'event and clk = '0' then
    if (enable_timer_5usec = '0') then
    if (enable_timer_5usec = '0') then
           timer_5usec_count <= (others => '0');
           timer_5usec_count <= (others => '0');
Line 621... Line 625...
  else
  else
         timer_5usec_done <= '0';
         timer_5usec_done <= '0';
  end if;
  end if;
end process;
end process;
 
 
 
--
 
-- Create the signals which indicate special scan codes received.
 
-- These are the "unlatched versions."
 
--
 
extend_release_decode : process( q, rx_shifting_done, extended, released )
 
begin
 
        if (q(8 downto 1) = EXTEND_CODE) and (rx_shifting_done = '1') then
 
                extended <= '1';
 
        else
 
                extended <= '0';
 
        end if;
 
 
 
        if (q(8 downto 1) = RELEASE_CODE) and (rx_shifting_done = '1') then
 
                released <= '1';
 
        else
 
                released <= '0';
 
        end if;
 
 
 
        if (rx_shifting_done = '1') and (extended = '0') and (released = '0') then
 
                rx_output_event <= '1';
 
        else
 
                rx_output_event <= '0';
 
        end if;
 
 
 
end process;
 
 
 
--
-- Store the special scan code status bits
-- Store the special scan code status bits
-- Not the final output, but an intermediate storage place,
-- Not the final output, but an intermediate storage place,
-- until the entire set of output data can be assembled.
-- until the entire set of output data can be assembled.
 
--
special_scan : process(clk, reset, rx_output_event, rx_shifting_done, extended, released )
special_scan : process(clk, reset, rx_output_event, rx_shifting_done, extended, released )
begin
begin
  if clk'event and clk='0' then
  if clk'event and clk='0' then
    if (reset = '1') or (rx_output_event = '1') then
    if (reset = '1') or (rx_output_event = '1') then
      hold_extended <= '0';
      hold_extended <= '0';
Line 640... Line 671...
      if (rx_shifting_done = '1') and (released = '1') then
      if (rx_shifting_done = '1') and (released = '1') then
             hold_released <= '1';
             hold_released <= '1';
      end if;
      end if;
    end if;
    end if;
  end if;
  end if;
 
 
end process;
end process;
 
 
 
--
 
-- convert scan code to ascii code
 
--
 
scan_to_ascii : process( shift_key_on, caps_key_on, q )
 
begin
 
        shift_key_plus_code <= shift_key_on & caps_key_on & q(7 downto 1);
 
end process;
 
 
 
--
-- These bits contain the status of the two shift keys
-- These bits contain the status of the two shift keys
 
--
left_shift_proc : process(clk, reset, q, rx_shifting_done, hold_released )
left_shift_proc : process(clk, reset, q, rx_shifting_done, hold_released )
begin
begin
  if clk'event and clk = '0' then
  if clk'event and clk = '0' then
    if (reset = '1') then
    if (reset = '1') then
           left_shift_key <= '0';
           left_shift_key <= '0';
    elsif (q(8 downto 1) = LEFT_SHIFT) and
                elsif (q(8 downto 1) = LEFT_SHIFT) and (rx_shifting_done = '1') then
               (rx_shifting_done = '1') and
                        left_shift_key <= not hold_released;
                         (hold_released = '0') then
 
      left_shift_key <= '1';
 
    elsif (q(8 downto 1) = LEFT_SHIFT) and
 
               (rx_shifting_done = '1') and
 
                         (hold_released = '1') then
 
      left_shift_key <= '0';
 
    end if;
    end if;
  end if;
  end if;
end process;
end process;
 
 
right_shift_proc : process(clk, reset, q, rx_shifting_done, hold_released )
right_shift_proc : process(clk, reset, q, rx_shifting_done, hold_released )
begin
begin
  if clk'event and clk = '0' then
  if clk'event and clk = '0' then
    if (reset = '1') then
    if (reset = '1') then
           right_shift_key <= '0';
           right_shift_key <= '0';
    elsif (q(8 downto 1) = RIGHT_SHIFT) and
                elsif (q(8 downto 1) = RIGHT_SHIFT) and (rx_shifting_done = '1') then
               (rx_shifting_done = '1') and
                        right_shift_key <= not hold_released;
                         (hold_released = '0') then
 
      right_shift_key <= '1';
 
    elsif (q(8 downto 1) = RIGHT_SHIFT) and
 
               (rx_shifting_done = '1') and
 
                         (hold_released = '1') then
 
      right_shift_key <= '0';
 
    end if;
    end if;
  end if;
  end if;
end process;
end process;
 
 
 
shift_proc : process( left_shift_key, right_shift_key, shift_key_on, caps_key_on, q )
 
begin
shift_key_on <= left_shift_key or right_shift_key;
shift_key_on <= left_shift_key or right_shift_key;
rx_shift_on <= shift_key_on;
rx_shift_on <= shift_key_on;
 
end process;
 
 
--
--
-- Control keys
-- Control keys
--
--
ctrl_proc : process(clk, reset, q, rx_shifting_done, hold_released )
ctrl_proc : process(clk, reset, q, rx_shifting_done, hold_released )
begin
begin
  if clk'event and clk = '0' then
  if clk'event and clk = '0' then
    if (reset = '1') then
    if (reset = '1') then
           ctrl_key_on <= '0';
           ctrl_key_on <= '0';
    elsif (q(8 downto 1) = CTRL_CODE) and
                elsif (q(8 downto 1) = CTRL_CODE) and (rx_shifting_done = '1') then
               (rx_shifting_done = '1') and
                        ctrl_key_on <= not hold_released;
                         (hold_released = '0') then
 
      ctrl_key_on <= '1';
 
    elsif (q(8 downto 1) = CTRL_CODE) and
 
               (rx_shifting_done = '1') and
 
                         (hold_released = '1') then
 
      ctrl_key_on <= '0';
 
    end if;
    end if;
  end if;
  end if;
end process;
end process;
 
 
--
--
Line 709... Line 735...
caps_proc : process(clk, reset, q, rx_shifting_done, hold_released, caps_key_on )
caps_proc : process(clk, reset, q, rx_shifting_done, hold_released, caps_key_on )
begin
begin
  if clk'event and clk = '0' then
  if clk'event and clk = '0' then
    if (reset = '1') then
    if (reset = '1') then
           caps_key_on <= '0';
           caps_key_on <= '0';
    elsif (q(8 downto 1) = CAPS_CODE) and
                elsif (q(8 downto 1) = CAPS_CODE) and (rx_shifting_done = '1') then
               (rx_shifting_done = '1') and
                        if (hold_released = '0') then
                         (hold_released = '0') then
 
      caps_key_on <= not caps_key_on;
      caps_key_on <= not caps_key_on;
    end if;
    end if;
  end if;
  end if;
 
        end if;
end process;
end process;
 
 
 
--
-- Output the special scan code flags, the scan code and the ascii
-- Output the special scan code flags, the scan code and the ascii
special_scan_proc : process(clk, reset,
--
 
special_scan_proc : process(clk, reset, rx_output_strobe,
                                                                         hold_extended, hold_released,
                                                                         hold_extended, hold_released,
                                                                         q, ascii, ctrl_key_on )
                                                        ascii, ctrl_key_on )
begin
begin
  if clk'event and clk = '0' then
  if clk'event and clk = '0' then
    if (reset = '1')    then
    if (reset = '1')    then
      rx_extended <= '0';
      rx_extended <= '0';
      rx_released <= '0';
      rx_released <= '0';
--      rx_scan_code <= "00000000";
                        rx_data <= (others=>'0');
      rx_data <= "00000000";
 
    elsif (rx_output_strobe = '1') then
    elsif (rx_output_strobe = '1') then
      rx_extended <= hold_extended;
      rx_extended <= hold_extended;
      rx_released <= hold_released;
      rx_released <= hold_released;
--      rx_scan_code <= q(8 downto 1);
                        if ctrl_key_on = '1' then
    elsif ctrl_key_on = '1' then
 
           rx_data <= ascii and x"1f";
           rx_data <= ascii and x"1f";
    else
    else
      rx_data <= ascii;
      rx_data <= ascii;
    end if;
    end if;
  end if;
  end if;
 
        end if;
end process;
end process;
 
 
 
--
-- Store the final rx output data only when all extend and release codes
-- Store the final rx output data only when all extend and release codes
-- are received and the next (actual key) scan code is also ready.
-- are received and the next (actual key) scan code is also ready.
-- (the presence of rx_extended or rx_released refers to the
-- (the presence of rx_extended or rx_released refers to the
-- the current latest scan code received, not the previously latched flags.)
-- the current latest scan code received, not the previously latched flags.)
 
--
rx_output_proc : process( clk, reset,
rx_output_proc : process( clk, reset,
                          rx_shifting_done, rx_output_strobe,
                          rx_shifting_done, rx_output_strobe,
                          extended, released,
                          extended, released,
 
                          hold_extended, hold_released,
                                                                  q, ascii, rx_read )
                                                                  q, ascii, rx_read )
begin
begin
  if (rx_shifting_done = '1') and (extended = '0') and (released = '0') then
 
    rx_output_event <= '1';
 
  else
 
    rx_output_event <= '0';
 
  end if;
 
 
 
  if clk'event and clk = '0' then
  if clk'event and clk = '0' then
    if reset = '1' then
    if reset = '1' then
           rx_output_strobe <= '0';
           rx_output_strobe <= '0';
    elsif (rx_shifting_done = '1') and
                elsif (rx_shifting_done = '1') and (rx_output_strobe = '0') and
          (rx_output_strobe = '0') and
                        (extended = '0') and (released = '0') and
               (extended = '0') and
 
                         (released = '0') and
 
                         (hold_released = '0' ) and
                         (hold_released = '0' ) and
          (ascii /= x"00" ) then
                        (ascii /= "00000000" ) then
--        ((TRAP_SHIFT_KEYS_PP = 0) or
--        ((TRAP_SHIFT_KEYS_PP = 0) or
--          ( (q(8 downto 1) /= RIGHT_SHIFT) and 
--          ( (q(8 downto 1) /= RIGHT_SHIFT) and 
--                 (q(8 downto 1) /= LEFT_SHIFT) and
--                 (q(8 downto 1) /= LEFT_SHIFT) and
--                      (q(8 downto 1) /= CTRL_CODE) ) )then
--                      (q(8 downto 1) /= CTRL_CODE) ) )then
      rx_output_strobe <= '1';
      rx_output_strobe <= '1';
Line 777... Line 798...
    end if;
    end if;
  end if;
  end if;
  rx_data_ready <= rx_output_strobe;
  rx_data_ready <= rx_output_strobe;
end process;
end process;
 
 
 
--
-- This part translates the scan code into an ASCII value...
-- This part translates the scan code into an ASCII value...
-- Only the ASCII codes which I considered important have been included.
-- Only the ASCII codes which I considered important have been included.
-- if you want more, just add the appropriate case statement lines...
-- if you want more, just add the appropriate case statement lines...
-- (You will need to know the keyboard scan codes you wish to assign.)
-- (You will need to know the keyboard scan codes you wish to assign.)
-- The entries are listed in ascending order of ASCII value.
-- The entries are listed in ascending order of ASCII value.
shift_key_plus_code <= shift_key_on & caps_key_on & q(7 downto 1);
--
 
 
--shift_map : process( shift_key_plus_code )
--shift_map : process( shift_key_plus_code )
--begin
--begin
--  case shift_key_plus_code is
--  case shift_key_plus_code is
--  when x"066" => ascii <= x"08";  -- Backspace ("backspace" key)
--  when x"066" => ascii <= x"08";  -- Backspace ("backspace" key)
--  when x"166" => ascii <= x"08";  -- Backspace ("backspace" key)
--  when x"166" => ascii <= x"08";  -- Backspace ("backspace" key)
Line 894... Line 914...
--  when x"15d" => ascii <= x"7c";  -- |
--  when x"15d" => ascii <= x"7c";  -- |
--  when x"15b" => ascii <= x"7d";  -- }
--  when x"15b" => ascii <= x"7d";  -- }
--  when x"10e" => ascii <= x"7e";  -- ~
--  when x"10e" => ascii <= x"7e";  -- ~
--  when x"071" => ascii <= x"7f";  -- (Delete OR DEL on numeric keypad)
--  when x"071" => ascii <= x"7f";  -- (Delete OR DEL on numeric keypad)
--  when x"171" => ascii <= x"7f";  -- (Delete OR DEL on numeric keypad)
--  when x"171" => ascii <= x"7f";  -- (Delete OR DEL on numeric keypad)
--  when others => ascii <= x"ff";  -- 0xff used for unlisted characters.
--  when others => ascii <= x"00";  -- 0xff used for unlisted characters.
--  end case;
--  end case;
--end process;
--end process;
 
 
 
 
end rtl;
end rtl;
 
 
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