Subversion Repositories open8_urisc

--               the ST/HD44780(U) control ASIC wired in either 8-bit or

--               the ST/HD44780(U) control ASIC wired in either 8-bit or

--               reduced (4-bit) mode.

--               reduced (4-bit) mode.

--              All low-level timing of the control signals are handled by this

--              All low-level timing of the control signals are handled by this

--               module, allowing client firmware to use a simple register

--               module, allowing client firmware to use a simple register

--               interface to program the LCD panel.

--               interface to program the LCD panel.

--

--

-- Register Map

-- Register Map

-- Address  Function

-- Address  Function

-- Offset  Bitfield Description                        Read/Write

-- Offset  Bitfield Description                        Read/Write

-- 0x0     AAAAAAAA LCD Register Write                 (Read-Write*)

-- 0x0     AAAAAAAA LCD Register Write                 (Read-Write*)

  Write_Qual                 : in  std_logic := '1';

  Write_Qual                 : in  std_logic := '1';

  Rd_Data                    : out DATA_TYPE;

  Rd_Data                    : out DATA_TYPE;

  Interrupt                  : out std_logic;

  Interrupt                  : out std_logic;

  --

  --

  LCD_E                      : out std_logic;

  LCD_E                      : out std_logic;

  LCD_RS                     : out std_logic;

  LCD_RS                     : out std_logic;

  LCD_DQ                     : out std_logic_vector(7 downto 0);

  LCD_DQ                     : out std_logic_vector(7 downto 0);

  LCD_BL                     : out std_logic

  LCD_BL                     : out std_logic

);

);

end entity;

end entity;

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

-- LCD and Register logic

-- LCD and Register logic

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

  LCD_Ctrl_proc: process( Clock, Reset )

  LCD_Ctrl_proc: process( Clock, Reset )

  begin

  begin

    if( Reset = Reset_Level )then

    if( Reset = Reset_Level )then

      ctrl_state             <= INIT;

      ctrl_state             <= INIT;

      hw_timer               <= (others => '0');

      hw_timer               <= (others => '0');