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sonicwave |
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-- Company: University of Southern Denmark
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-- Engineer: Simon Falsig
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--
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-- Create Date: 19/03/2010
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-- Design Name: uTosNet
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-- Module Name: uTosNet_usb - Behavioral
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-- Project Name: uTosNet
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-- Target Devices: SDU XC3S50AN Board
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-- Tool versions: Xilinx ISE 11.4
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-- Description: This module implements a very simple ASCII based protocol over
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-- a uart. Data can be read and written from and to one port of a
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-- dual-port blockRAM, where the other blockRAM port is available
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-- to the user application. Communication takes place at the fol-
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-- lowing settings:
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-- Baudrate: 115200 kbps
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-- Parity: none
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-- Bits: 8 data bits, 1 stop bit
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-- Flowcontrol: none
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-- The protocol format can be seen in the documentation files.
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--
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-- Focus has mostly been on a simple implementation, as the
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-- module is to be used during courses at the university.
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--
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-- Dependencies: The module uses the uart implementation from Ken Chapmans
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-- PicoBlaze. More specifically the following files:
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-- uart_rx.vhd
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-- kcuart_rx.vhd
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-- bbfifo_16x8.vhd
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-- uart_tx.vhd
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-- kcuart_tx.vhd
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-- These files can be downloaded from Xilinx:
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-- https://secure.xilinx.com/webreg/register.do?group=picoblaze
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--
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-- It should not be hard to implement the module using another
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-- uart implementation though.
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--
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-- Revision:
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-- Revision 0.10 - Initial release
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--
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----------------------------------------------------------------------------------
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library IEEE;
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use IEEE.STD_LOGIC_1164.ALL;
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use IEEE.STD_LOGIC_ARITH.ALL;
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use IEEE.STD_LOGIC_UNSIGNED.ALL;
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---- Uncomment the following library declaration if instantiating
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---- any Xilinx primitives in this code.
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--library UNISIM;
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--use UNISIM.VComponents.all;
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entity uTosNet_uart is
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Port ( clk_50M : in STD_LOGIC;
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serial_out : out STD_LOGIC;
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serial_in : in STD_LOGIC;
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dataReg_addr : in STD_LOGIC_VECTOR(5 downto 0);
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dataReg_dataIn : in STD_LOGIC_VECTOR(31 downto 0);
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dataReg_dataOut : out STD_LOGIC_VECTOR(31 downto 0);
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dataReg_clk : in STD_LOGIC;
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dataReg_writeEnable : in STD_LOGIC);
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end uTosNet_uart;
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architecture Behavioral of uTosNet_uart is
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component dataRegister
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Port ( clka : in STD_LOGIC;
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wea : in STD_LOGIC_VECTOR(0 downto 0);
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addra : in STD_LOGIC_VECTOR(5 downto 0);
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dina : in STD_LOGIC_VECTOR(31 downto 0);
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douta : out STD_LOGIC_VECTOR(31 downto 0);
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clkb : in STD_LOGIC;
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web : in STD_LOGIC_VECTOR(0 downto 0);
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addrb : in STD_LOGIC_VECTOR(5 downto 0);
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dinb : in STD_LOGIC_VECTOR(31 downto 0);
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doutb : out STD_LOGIC_VECTOR(31 downto 0));
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end component;
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component uart_rx
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Port ( serial_in : in STD_LOGIC;
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data_out : out STD_LOGIC_VECTOR(7 downto 0);
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read_buffer : in STD_LOGIC;
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reset_buffer : in STD_LOGIC;
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en_16_x_baud : in STD_LOGIC;
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buffer_data_present : out STD_LOGIC;
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buffer_full : out STD_LOGIC;
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buffer_half_full : out STD_LOGIC;
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clk : in STD_LOGIC);
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end component;
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component uart_tx
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Port ( serial_out : out STD_LOGIC;
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data_in : in STD_LOGIC_VECTOR(7 downto 0);
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write_buffer : in STD_LOGIC;
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reset_buffer : in STD_LOGIC;
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en_16_x_baud : in STD_LOGIC;
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buffer_full : out STD_LOGIC;
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buffer_half_full : out STD_LOGIC;
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clk : in STD_LOGIC);
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end component;
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signal baudCount : integer range 0 to 36 :=0;
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signal en_16_x_baud : STD_LOGIC;
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signal readFromUart : STD_LOGIC;
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signal rxData : STD_LOGIC_VECTOR(7 downto 0);
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signal rxDataPresent : STD_LOGIC;
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signal rxFull : STD_LOGIC;
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signal rxHalfFull : STD_LOGIC;
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signal txData : STD_LOGIC_VECTOR(7 downto 0);
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signal writeToUart : STD_LOGIC;
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signal txFull : STD_LOGIC;
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signal txHalfFull : STD_LOGIC;
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constant UARTDIV : STD_LOGIC_VECTOR(5 downto 0) := "011010";
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type STATES is (IDLE, COMMAND_IN, WAIT1, REG_IN, WAIT2, INDEX_IN, WAIT3, SPACE_IN, WAIT4, DATA_IN, WAIT_DATA_IN, DATA_OUT, PERFORM_READ_SETUP, PERFORM_READ_CLK, PERFORM_READ_DONE, PERFORM_WRITE_SETUP, PERFORM_WRITE_CLK, PERFORM_WRITE_DONE);
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signal state : STATES := IDLE;
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signal nextState : STATES := IDLE;
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type COMMANDS is (CMD_NONE, CMD_READ, CMD_WRITE, CMD_COMMIT_READ, CMD_COMMIT_WRITE);
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signal currentCommand : COMMANDS := CMD_NONE;
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signal int_dataReg_dataIn : STD_LOGIC_VECTOR(31 downto 0);
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signal int_dataReg_addr : STD_LOGIC_VECTOR(5 downto 0);
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signal int_dataReg_dataOut : STD_LOGIC_VECTOR(31 downto 0);
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signal int_dataReg_we : STD_LOGIC_VECTOR(0 downto 0);
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signal int_dataReg_clk : STD_LOGIC;
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signal dataReg_writeEnable_V : STD_LOGIC_VECTOR(0 downto 0);
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signal inputBuffer : STD_LOGIC_VECTOR(31 downto 0) := (others => '0');
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signal outputBuffer : STD_LOGIC_VECTOR(31 downto 0) := (others => '1');
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signal readCounter : STD_LOGIC_VECTOR(3 downto 0) := (others => '0');
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signal writeCounter : STD_LOGIC_VECTOR(3 downto 0) := (others => '0');
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signal currentReg : STD_LOGIC_VECTOR(2 downto 0) := (others => '0');
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signal currentIndex : STD_LOGIC_VECTOR(2 downto 0) := (others => '0');
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signal commitRead : STD_LOGIC := '0';
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signal commitWrite : STD_LOGIC := '0';
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begin
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dataReg_writeEnable_V(0) <= dataReg_writeEnable; --Conversion from std_logic to std_logic_vector(0 downto 0) - to allow for dataReg_writeEnable to be a std_logic, which is nicer...:)
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dataRegisterInst : dataRegister --Instantation of the dual-port blockram used for the dataregister
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Port map ( clka => dataReg_clk, --PortA is used for the user application
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wea => dataReg_writeEnable_V, --
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addra => dataReg_addr, --
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dina => dataReg_dataIn, --
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douta => dataReg_dataOut, --
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clkb => int_dataReg_clk, --PortB is used for the SPI interface
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web => int_dataReg_we, --
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addrb => int_dataReg_addr, --
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dinb => int_dataReg_dataIn, --
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doutb => int_dataReg_dataOut); --
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rx_inst: uart_rx
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Port map ( serial_in => serial_in,
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data_out => rxData,
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read_buffer => readFromUart,
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reset_buffer => '0',
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en_16_x_baud => en_16_x_baud,
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buffer_data_present => rxDataPresent,
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buffer_full => rxFull,
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buffer_half_full => rxHalfFull,
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clk => clk_50M );
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tx_inst : uart_tx
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Port map ( serial_out => serial_out,
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data_in => txData,
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write_buffer => writeToUart,
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reset_buffer => '0',
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en_16_x_baud => en_16_x_baud,
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buffer_full => txFull,
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buffer_half_full => txHalfFull,
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clk => clk_50M);
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baudTimer_inst: process(clk_50M)
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begin
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if(clk_50M'event and clk_50M='1')then
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if(baudCount = UARTDIV)then
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baudCount <= 0;
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en_16_x_baud <= '1';
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else
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baudCount <= baudCount + 1;
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en_16_x_baud <= '0';
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end if;
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end if;
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end process baudTimer_inst;
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process(clk_50M)
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begin
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if(clk_50M = '1' and clk_50M'event) then
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state <= nextState;
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readFromUart <= '0';
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writeToUart <= '0';
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case state is
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when IDLE =>
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currentCommand <= CMD_NONE;
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readCounter <= (others => '0');
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writeCounter <= (others => '0');
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commitRead <= '0';
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commitWrite <= '0';
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when COMMAND_IN =>
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commitRead <= '0';
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commitWrite <= '0';
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if(rxDataPresent = '1') then
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case rxData is
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when "01110010" => --'r'
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currentCommand <= CMD_READ;
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when "01110111" => --'w'
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currentCommand <= CMD_WRITE;
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when "01110100" => --'t'
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commitRead <= '1';
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currentCommand <= CMD_NONE;
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when "01100011" => --'c'
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commitWrite <= '1';
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currentCommand <= CMD_NONE;
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when others =>
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currentCommand <= CMD_NONE;
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end case;
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readFromUart <= '1';
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end if;
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when WAIT1 =>
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when REG_IN =>
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if(rxDataPresent = '1') then
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case rxData is
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when "00110000" =>
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currentReg <= "000";
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when "00110001" =>
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currentReg <= "001";
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when "00110010" =>
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currentReg <= "010";
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when "00110011" =>
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currentReg <= "011";
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when "00110100" =>
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currentReg <= "100";
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when "00110101" =>
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currentReg <= "101";
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when "00110110" =>
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currentReg <= "110";
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when "00110111" =>
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currentReg <= "111";
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when others =>
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currentCommand <= CMD_NONE;
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end case;
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readFromUart <= '1';
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end if;
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when WAIT2 =>
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when INDEX_IN =>
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if(rxDataPresent = '1') then
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case rxData is
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when "00110000" =>
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currentIndex <= "000";
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when "00110001" =>
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currentIndex <= "001";
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when "00110010" =>
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currentIndex <= "010";
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when "00110011" =>
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currentIndex <= "011";
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when "00110100" =>
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currentIndex <= "100";
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when "00110101" =>
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currentIndex <= "101";
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when "00110110" =>
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currentIndex <= "110";
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when "00110111" =>
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currentIndex <= "111";
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when others =>
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currentCommand <= CMD_NONE;
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end case;
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readFromUart <= '1';
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end if;
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when WAIT3 =>
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when SPACE_IN =>
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if(rxDataPresent = '1') then
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if(not(rxData = "00100000")) then
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currentCommand <= CMD_NONE;
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end if;
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readFromUart <= '1';
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end if;
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when WAIT4 =>
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when DATA_IN =>
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if(rxDataPresent = '1') then
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case rxData is
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when "00110000" => --'0'
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inputBuffer <= inputBuffer(27 downto 0) & "0000";
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when "00110001" => --'1'
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inputBuffer <= inputBuffer(27 downto 0) & "0001";
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when "00110010" => --'2'
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inputBuffer <= inputBuffer(27 downto 0) & "0010";
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when "00110011" => --'3'
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inputBuffer <= inputBuffer(27 downto 0) & "0011";
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when "00110100" => --'4'
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inputBuffer <= inputBuffer(27 downto 0) & "0100";
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when "00110101" => --'5'
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inputBuffer <= inputBuffer(27 downto 0) & "0101";
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when "00110110" => --'6'
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inputBuffer <= inputBuffer(27 downto 0) & "0110";
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when "00110111" => --'7'
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inputBuffer <= inputBuffer(27 downto 0) & "0111";
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when "00111000" => --'8'
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inputBuffer <= inputBuffer(27 downto 0) & "1000";
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when "00111001" => --'9'
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inputBuffer <= inputBuffer(27 downto 0) & "1001";
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when "01100001" => --'a'
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inputBuffer <= inputBuffer(27 downto 0) & "1010";
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when "01100010" => --'b'
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inputBuffer <= inputBuffer(27 downto 0) & "1011";
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when "01100011" => --'c'
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inputBuffer <= inputBuffer(27 downto 0) & "1100";
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when "01100100" => --'d'
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inputBuffer <= inputBuffer(27 downto 0) & "1101";
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when "01100101" => --'e'
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inputBuffer <= inputBuffer(27 downto 0) & "1110";
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when "01100110" => --'f'
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inputBuffer <= inputBuffer(27 downto 0) & "1111";
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when others =>
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currentCommand <= CMD_NONE;
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end case;
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readFromUart <= '1';
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readCounter <= readCounter + 1;
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end if;
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when WAIT_DATA_IN =>
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when DATA_OUT =>
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writeToUart <= '1';
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if(writeCounter = 8) then
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|
|
txData <= "00100000"; --Transmit a space to make thinks look nicer...:)
|
336 |
|
|
else
|
337 |
|
|
case outputBuffer(31 downto 28) is
|
338 |
|
|
when "0000" => --'0'
|
339 |
|
|
txData <= "00110000";
|
340 |
|
|
when "0001" => --'1'
|
341 |
|
|
txData <= "00110001";
|
342 |
|
|
when "0010" => --'2'
|
343 |
|
|
txData <= "00110010";
|
344 |
|
|
when "0011" => --'3'
|
345 |
|
|
txData <= "00110011";
|
346 |
|
|
when "0100" => --'4'
|
347 |
|
|
txData <= "00110100";
|
348 |
|
|
when "0101" => --'5'
|
349 |
|
|
txData <= "00110101";
|
350 |
|
|
when "0110" => --'6'
|
351 |
|
|
txData <= "00110110";
|
352 |
|
|
when "0111" => --'7'
|
353 |
|
|
txData <= "00110111";
|
354 |
|
|
when "1000" => --'8'
|
355 |
|
|
txData <= "00111000";
|
356 |
|
|
when "1001" => --'9'
|
357 |
|
|
txData <= "00111001";
|
358 |
|
|
when "1010" => --'a'
|
359 |
|
|
txData <= "01100001";
|
360 |
|
|
when "1011" => --'b'
|
361 |
|
|
txData <= "01100010";
|
362 |
|
|
when "1100" => --'c'
|
363 |
|
|
txData <= "01100011";
|
364 |
|
|
when "1101" => --'d'
|
365 |
|
|
txData <= "01100100";
|
366 |
|
|
when "1110" => --'e'
|
367 |
|
|
txData <= "01100101";
|
368 |
|
|
when "1111" => --'f'
|
369 |
|
|
txData <= "01100110";
|
370 |
|
|
when others =>
|
371 |
|
|
end case;
|
372 |
|
|
end if;
|
373 |
|
|
outputBuffer <= outputBuffer(27 downto 0) & "0000";
|
374 |
|
|
writeCounter <= writeCounter + 1;
|
375 |
|
|
when PERFORM_READ_SETUP =>
|
376 |
|
|
int_dataReg_addr <= currentReg & currentIndex;
|
377 |
|
|
int_dataReg_we <= "0";
|
378 |
|
|
int_dataReg_clk <= '0';
|
379 |
|
|
when PERFORM_READ_CLK =>
|
380 |
|
|
int_dataReg_clk <= '1';
|
381 |
|
|
when PERFORM_READ_DONE =>
|
382 |
|
|
outputBuffer <= int_dataReg_dataOut;
|
383 |
|
|
int_dataReg_clk <= '0';
|
384 |
|
|
when PERFORM_WRITE_SETUP =>
|
385 |
|
|
int_dataReg_addr <= currentReg & currentIndex;
|
386 |
|
|
int_dataReg_dataIn <= inputBuffer;
|
387 |
|
|
int_dataReg_we <= "1";
|
388 |
|
|
int_dataReg_clk <= '0';
|
389 |
|
|
when PERFORM_WRITE_CLK =>
|
390 |
|
|
int_dataReg_clk <= '1';
|
391 |
|
|
when PERFORM_WRITE_DONE =>
|
392 |
|
|
int_dataReg_we <= "0";
|
393 |
|
|
int_dataReg_clk <= '0';
|
394 |
|
|
end case;
|
395 |
|
|
end if;
|
396 |
|
|
end process;
|
397 |
|
|
|
398 |
|
|
process(state, rxDataPresent, currentCommand, readCounter, writeCounter)
|
399 |
|
|
begin
|
400 |
|
|
if((currentCommand = CMD_NONE) and not ((state = COMMAND_IN) or (state = IDLE))) then
|
401 |
|
|
nextState <= IDLE;
|
402 |
|
|
else
|
403 |
|
|
case state is
|
404 |
|
|
when IDLE =>
|
405 |
|
|
nextState <= COMMAND_IN;
|
406 |
|
|
when COMMAND_IN =>
|
407 |
|
|
if(rxDataPresent = '1') then
|
408 |
|
|
nextState <= WAIT1;
|
409 |
|
|
else
|
410 |
|
|
nextState <= COMMAND_IN;
|
411 |
|
|
end if;
|
412 |
|
|
when WAIT1 =>
|
413 |
|
|
if(rxDataPresent = '0') then
|
414 |
|
|
nextState <= REG_IN;
|
415 |
|
|
else
|
416 |
|
|
nextState <= WAIT1;
|
417 |
|
|
end if;
|
418 |
|
|
when REG_IN =>
|
419 |
|
|
if(rxDataPresent = '1') then
|
420 |
|
|
nextState <= WAIT2;
|
421 |
|
|
else
|
422 |
|
|
nextState <= REG_IN;
|
423 |
|
|
end if;
|
424 |
|
|
when WAIT2 =>
|
425 |
|
|
if(rxDataPresent = '0') then
|
426 |
|
|
nextState <= INDEX_IN;
|
427 |
|
|
else
|
428 |
|
|
nextState <= WAIT2;
|
429 |
|
|
end if;
|
430 |
|
|
when INDEX_IN =>
|
431 |
|
|
if(rxDataPresent = '1') then
|
432 |
|
|
nextState <= WAIT3;
|
433 |
|
|
else
|
434 |
|
|
nextState <= INDEX_IN;
|
435 |
|
|
end if;
|
436 |
|
|
when WAIT3 =>
|
437 |
|
|
if(rxDataPresent = '0') then
|
438 |
|
|
if(currentCommand = CMD_READ) then
|
439 |
|
|
nextState <= PERFORM_READ_SETUP;
|
440 |
|
|
else
|
441 |
|
|
nextState <= SPACE_IN;
|
442 |
|
|
end if;
|
443 |
|
|
else
|
444 |
|
|
nextState <= WAIT3;
|
445 |
|
|
end if;
|
446 |
|
|
when SPACE_IN =>
|
447 |
|
|
if(rxDataPresent = '1') then
|
448 |
|
|
nextState <= WAIT4;
|
449 |
|
|
else
|
450 |
|
|
nextState <= SPACE_IN;
|
451 |
|
|
end if;
|
452 |
|
|
when WAIT4 =>
|
453 |
|
|
if(rxDataPresent = '0') then
|
454 |
|
|
nextState <= DATA_IN;
|
455 |
|
|
else
|
456 |
|
|
nextState <= WAIT4;
|
457 |
|
|
end if;
|
458 |
|
|
when DATA_IN =>
|
459 |
|
|
if(rxDataPresent = '1') then
|
460 |
|
|
nextState <= WAIT_DATA_IN;
|
461 |
|
|
else
|
462 |
|
|
nextState <= DATA_IN;
|
463 |
|
|
end if;
|
464 |
|
|
when WAIT_DATA_IN =>
|
465 |
|
|
if(rxDataPresent = '0') then
|
466 |
|
|
if(readCounter = 8) then
|
467 |
|
|
nextState <= PERFORM_WRITE_SETUP;
|
468 |
|
|
else
|
469 |
|
|
nextState <= DATA_IN;
|
470 |
|
|
end if;
|
471 |
|
|
else
|
472 |
|
|
nextState <= WAIT_DATA_IN;
|
473 |
|
|
end if;
|
474 |
|
|
when DATA_OUT =>
|
475 |
|
|
if(writeCounter = 8) then
|
476 |
|
|
nextState <= IDLE;
|
477 |
|
|
else
|
478 |
|
|
nextState <= DATA_OUT;
|
479 |
|
|
end if;
|
480 |
|
|
when PERFORM_READ_SETUP =>
|
481 |
|
|
nextState <= PERFORM_READ_CLK;
|
482 |
|
|
when PERFORM_READ_CLK =>
|
483 |
|
|
nextState <= PERFORM_READ_DONE;
|
484 |
|
|
when PERFORM_READ_DONE =>
|
485 |
|
|
nextState <= DATA_OUT;
|
486 |
|
|
when PERFORM_WRITE_SETUP =>
|
487 |
|
|
nextState <= PERFORM_WRITE_CLK;
|
488 |
|
|
when PERFORM_WRITE_CLK =>
|
489 |
|
|
nextState <= PERFORM_WRITE_DONE;
|
490 |
|
|
when PERFORM_WRITE_DONE =>
|
491 |
|
|
nextState <= IDLE;
|
492 |
|
|
end case;
|
493 |
|
|
end if;
|
494 |
|
|
end process;
|
495 |
|
|
|
496 |
|
|
end Behavioral;
|
497 |
|
|
|