Subversion Repositories djpeg

//---------------------------------------------------------------------------

// File Name    : jpeg_dht.v

// Module Name  : jpeg_dht

// Description  : DHT space

// Project      : JPEG Decoder

// Belong to    : 

// Author       : H.Ishihara

// E-Mail       : hidemi@sweetcafe.jp

// HomePage     : http://www.sweetcafe.jp/

// Date         : 2006/10/01

// Rev.         : 1.1

//---------------------------------------------------------------------------

// Rev. Date         Description

//---------------------------------------------------------------------------

// 1.01 2006/10/01 1st Release

//---------------------------------------------------------------------------

`timescale 1ps / 1ps

module jpeg_dht(

    rst,

    clk,

    DataInEnable,

    DataInColor,

    DataInCount,

    DataIn,

    ColorNumber,

    TableNumber,

    ZeroTable,

    WidhtTable

    );

    input           rst;

    input           clk;

    input           DataInEnable;

    input [1:0]     DataInColor;

    input [7:0]     DataInCount;

    input [7:0]     DataIn;

    input [1:0]     ColorNumber;

    input [7:0]     TableNumber;

    output [3:0]    ZeroTable;

    output [3:0]    WidhtTable;

    // RAM

    reg [7:0]       DHT_Ydc [0:15];

    reg [7:0]       DHT_Yac [0:255];

    reg [7:0]       DHT_Cdc [0:15];

    reg [7:0]       DHT_Cac [0:255];

    reg [7:0]       ReadDataYdc;

    reg [7:0]       ReadDataYac;

    reg [7:0]       ReadDataCdc;

    reg [7:0]       ReadDataCac;

    wire [7:0]      ReadData;

    // RAM

    always @(posedge clk) begin

        if(DataInEnable ==1'b1 & DataInColor ==2'b00) begin

            DHT_Ydc[DataInCount[3:0]] <= DataIn;

        end

        if(DataInEnable ==1'b1 & DataInColor ==2'b01) begin

            DHT_Yac[DataInCount] <= DataIn;

        end

        if(DataInEnable ==1'b1 & DataInColor ==2'b10) begin

            DHT_Cdc[DataInCount[3:0]] <= DataIn;

        end

        if(DataInEnable ==1'b1 & DataInColor ==2'b11) begin

            DHT_Cac[DataInCount] <= DataIn;

        end

    end

    always @(posedge clk) begin

        ReadDataYdc <= DHT_Ydc[TableNumber[3:0]];

        ReadDataYac <= DHT_Yac[TableNumber];

        ReadDataCdc <= DHT_Cdc[TableNumber[3:0]];

        ReadDataCac <= DHT_Cac[TableNumber];

    end

    // Selector

    function [7:0] ReadDataSel;

        input [1:0]    ColorNumber;

        input [7:0]    ReadDataYdc;

        input [7:0]    ReadDataYac;

        input [7:0]    ReadDataCdc;

        input [7:0]    ReadDataCac;

        begin

            case (ColorNumber)

            2'b00: ReadDataSel = ReadDataYdc;

            2'b01: ReadDataSel = ReadDataYac;

            2'b10: ReadDataSel = ReadDataCdc;

            2'b11: ReadDataSel = ReadDataCac;

            endcase

        end

    endfunction

    assign ReadData = ReadDataSel(ColorNumber, ReadDataYdc, ReadDataYac, ReadDataCdc, ReadDataCac);

    assign ZeroTable  = ReadData[7:4];

    assign WidhtTable = ReadData[3:0];

endmodule