Subversion Repositories pipelined_fft_128

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////  FFT/IFFT 128 points transform                              ////

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////  Authors: Anatoliy Sergienko, Volodya Lepeha                ////

////  Company: Unicore Systems http://unicore.co.ua              ////

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////  Downloaded from: http://www.opencores.org                  ////

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//// Copyright (C) 2006-2010 Unicore Systems LTD                 ////

//// www.unicore.co.ua                                           ////

//// o.uzenkov@unicore.co.ua                                     ////

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//// This source file may be used and distributed without        ////

//// restriction provided that this copyright statement is not   ////

//// removed from the file and that any derivative work contains ////

//// the original copyright notice and the associated disclaimer.////

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//// THIS SOFTWARE IS PROVIDED "AS IS"                           ////

//// AND ANY EXPRESSED OR IMPLIED WARRANTIES,                    ////

//// INCLUDING, BUT NOT LIMITED TO, THE IMPLIED                  ////

//// WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT              ////

//// AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.        ////

//// IN NO EVENT SHALL THE UNICORE SYSTEMS OR ITS                ////

//// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,            ////

//// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL            ////

//// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT         ////

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//// WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT              ////

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//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~           

// DESCRIPTION  :       Store buffer

// FUNCTION:            FIFO - buffer with direct input order and 8-th inverse output order

//      FILES:                          BUFRAM128C_2.v  - 1-st,2-nd,3-d data buffer, contains:

//                                                      RAM2x128C.v - dual ported synchronous RAM, contains:            

//                                                                      RAM128.v -single ported synchronous RAM

//  PROPERTIES: 1) Has the volume of 2x128 complex data

//                                                      2) Contains 2- port RAM and address counter

//                                                      3)Has 128-clock cycle period starting with the START impulse

//                          and continuing forever    

//                                                4) Signal RDY precedes the 1-st correct datum outputted from the buffer

//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

`timescale 1 ns / 1 ps

`include "FFT128_CONFIG.inc"

module BUFRAM128C_2 ( CLK ,RST ,ED ,START ,DR ,DI ,RDY ,DOR ,DOI );

        `FFT128paramnb

        output RDY ;

        reg RDY ;

        output [nb-1:0] DOR ;

        wire [nb-1:0] DOR ;

        output [nb-1:0] DOI ;

        wire [nb-1:0] DOI ;

        input CLK ;

        wire CLK ;

        input RST ;

        wire RST ;

        input ED ;

        wire ED ;

        input START ;

        wire START ;

        input [nb-1:0] DR ;

        wire [nb-1:0] DR ;

        input [nb-1:0] DI ;

        wire [nb-1:0] DI ;

        wire odd, we;

        wire [6:0] addrw,addrr;

        reg [7:0] addr;

        reg [8:0] ct2;           //counter for the RDY signal                              

        always @(posedge CLK)   //   CTADDR

                begin

                        if (RST) begin

                                        addr<=7'b000_0000;

                                        ct2<= 8'b1000_0001;

                                RDY<=1'b0; end

                        else if (START) begin

                                        addr<=7'b000_0000;

                                        ct2<= 8'b0000_0000;

                                RDY<=1'b0;end

                        else if (ED)    begin

                                RDY<=1'b0;

                                        addr<=addr+1;

                                        if (ct2!=129)

                                        ct2<=ct2+1;

                                        if (ct2==128)

                                         RDY<=1'b1;

                                end

                end

assign  addrw=  addr[6:0];

assign  odd=addr[7];                            // signal which switches the 2 parts of the buffer

assign  addrr={addr[3 : 0], addr[6 : 4]};          // 8-th inverse output address

assign  we = ED;

        RAM2x128C #(nb) URAM(.CLK(CLK),.ED(ED),.WE(we),.ODD(odd),

        .ADDRW(addrw),  .ADDRR(addrr),

        .DR(DR),.DI(DI),

        .DOR(DOR),      .DOI(DOI));

endmodule