Subversion Repositories uart_block

--! @file

--! @brief Top wishbone slave for the uart (Connects uart_control and uart_communication_blocks)

library IEEE;

use IEEE.STD_LOGIC_1164.ALL;

--! Use CPU Definitions package

use work.pkgDefinitions.all;

entity uart_wishbone_slave is

    Port ( RST_I : in  STD_LOGIC;                                                               --! Reset Input

           CLK_I : in  STD_LOGIC;                                                               --! Clock Input

           ADR_I0 : in  STD_LOGIC_VECTOR (1 downto 0);   --! Address input

           DAT_I0 : in  STD_LOGIC_VECTOR (31 downto 0);  --! Data Input 0

           DAT_O0 : out  STD_LOGIC_VECTOR (31 downto 0); --! Data Output 0

           WE_I : in  STD_LOGIC;                                                                        --! Write enable input

           STB_I : in  STD_LOGIC;                                                               --! Strobe input (Works like a chip select)

           ACK_O : out  STD_LOGIC;                                                              --! Ack output

                          -- NON-WISHBONE Signals

                          serial_in : in std_logic;                                                     --! Uart serial input

                          data_Avaible : out std_logic;                                         --! Flag to indicate data avaible                                       

                          serial_out : out std_logic

                          );

end uart_wishbone_slave;

--! @brief Top uart_wishbone_slave architecture

--! @details Connect the control unit and the communication blocks

architecture Behavioral of uart_wishbone_slave is

component uart_control is

   Port ( rst : in  std_logic;                                                                                                          --! Global reset

           clk : in  std_logic;                                                                                                         --! Global clock

                          WE    : in std_logic;                                                                                                         --! Write enable

           reg_addr : in  std_logic_vector (1 downto 0);                                         --! Register address

                          start : in std_logic;                                                                                                         --! Start (Strobe)

                          done : out std_logic;                                                                                                         --! Done (ACK)

           DAT_I : in  std_logic_vector ((nBitsLarge-1) downto 0);               --! Data Input (Wishbone)

           DAT_O : out  std_logic_vector ((nBitsLarge-1) downto 0);              --! Data output (Wishbone)

                          baud_wait : out std_logic_vector ((nBitsLarge-1) downto 0);    --! Signal to control the baud rate frequency

                          data_byte_tx : out std_logic_vector((nBits-1) downto 0);               --! 1 Byte to be send to serial_transmitter

                          data_byte_rx : in std_logic_vector((nBits-1) downto 0);        --! 1 Byte to be received by serial_receiver

           tx_data_sent : in  std_logic;                                                                                        --! Signal comming from serial_transmitter

                          tx_start : out std_logic;                                                                                             --! Signal to start sending serial data...

                          rst_comm_blocks : out std_logic;                                                                              --! Reset Communication blocks                    

           rx_data_ready : in  std_logic);

end component;

component uart_communication_blocks is

    Port ( rst : in  STD_LOGIC;                                                                                                                 --! Global reset

           clk : in  STD_LOGIC;                                                                                                                 --! Global clock

                          cycle_wait_baud : in std_logic_vector((nBitsLarge-1) downto 0);        --! Number of cycles to wait in order to generate desired baud

           byte_tx : in  STD_LOGIC_VECTOR ((nBits-1) downto 0);                          --! Byte to transmit

           byte_rx : out  STD_LOGIC_VECTOR ((nBits-1) downto 0);                         --! Byte to receive

           data_sent_tx : out  STD_LOGIC;                                                                                               --! Indicate that byte has been sent

           data_received_rx : out  STD_LOGIC;                                                                           --! Indicate that we got a byte

                          serial_out : out std_logic;                                                                                                   --! Uart serial out

                          serial_in : in std_logic;                                                                                                     --! Uart serial in

           start_tx : in  STD_LOGIC);                                                                                                   --! Initiate transmission

end component;

signal baud_wait : std_logic_vector((nBitsLarge-1) downto 0);

signal tx_data_sent : std_logic;

signal tx_start : std_logic;

signal rst_comm_blocks : std_logic;

signal rx_data_ready : std_logic;

signal data_byte_tx : std_logic_vector(7 downto 0);

signal data_byte_rx : std_logic_vector(7 downto 0);

begin

        --! Instantiate uart_control

        uUartControl : uart_control port map (

                rst => RST_I,

                clk => CLK_I,

                WE      => WE_I,

                reg_addr => ADR_I0,

                start => STB_I,

                done => ACK_O,

                DAT_I => DAT_I0,

                DAT_O => DAT_O0,

                baud_wait => baud_wait,

                data_byte_tx => data_byte_tx,

                data_byte_rx => data_byte_rx,

                tx_data_sent => tx_data_sent,

                rst_comm_blocks => rst_comm_blocks,

                tx_start => tx_start,

                rx_data_ready => rx_data_ready

        );

        --! Instantiate uart_communication_blocks

        uUartCommunicationBlocks : uart_communication_blocks port map (

                rst => rst_comm_blocks,

                clk => CLK_I,

                cycle_wait_baud => baud_wait,

                byte_tx => data_byte_tx,

                byte_rx => data_byte_rx,

                data_sent_tx => tx_data_sent,

                data_received_rx => rx_data_ready,

                serial_out => serial_out,

                serial_in => serial_in,

                start_tx => tx_start

        );

        data_Avaible <= rx_data_ready;

end Behavioral;