m3s055ct.v

这是16位定点dsp源代码。已仿真和综合过了

//*******************************************************************       //
//IMPORTANT NOTICE                                                          //
//================                                                          //
//Copyright Mentor Graphics Corporation 1996 - 1998.  All rights reserved.  //
//This file and associated deliverables are the trade secrets,              //
//confidential information and copyrighted works of Mentor Graphics         //
//Corporation and its licensors and are subject to your license agreement   //
//with Mentor Graphics Corporation.                                         //
//                                                                          //
//These deliverables may be used for the purpose of making silicon for one  //
//IC design only.  No further use of these deliverables for the purpose of  //
//making silicon from an IC design is permitted without the payment of an   //
//additional license fee.  See your license agreement with Mentor Graphics  //
//for further details.  If you have further questions please contact        //
//Mentor Graphics Customer Support.                                         //
//                                                                          //
//This Mentor Graphics core (m320c50eng v1999.010) was extracted on         //
//workstation hostid 800059c1 Inventra                                      //
// 16-bit Adder
// Copyright Mentor Graphics Corporation and Licensors 1998.
// V1.0

// m3s055ct
// M320C50 Auxillary register arithmetic unit adder.
// 16-bit look-ahead adder with carry in and carry out

`define C_Carry_Slice 4  // Number of bits in a carry slice


module m3s055ct (CarryIn, AdderIpA, AdderIpB, AdderOp, CarryOut);
//*******************************************************************       //
//IMPORTANT NOTICE                                                          //
//================                                                          //
//Copyright Mentor Graphics Corporation 1996 - 1998.  All rights reserved.  //
//This file and associated deliverables are the trade secrets,              //
//confidential information and copyrighted works of Mentor Graphics         //
//Corporation and its licensors and are subject to your license agreement   //
//with Mentor Graphics Corporation.                                         //
//                                                                          //
//These deliverables may be used for the purpose of making silicon for one  //
//IC design only.  No further use of these deliverables for the purpose of  //
//making silicon from an IC design is permitted without the payment of an   //
//additional license fee.  See your license agreement with Mentor Graphics  //
//for further details.  If you have further questions please contact        //
//Mentor Graphics Customer Support.                                         //
//                                                                          //
//This Mentor Graphics core (m320c50eng v1999.010) was extracted on         //
//workstation hostid 800059c1 Inventra                                      //
    input         CarryIn;
    input  [15:0] AdderIpA, AdderIpB;
    output [15:0] AdderOp;
    output        CarryOut;

    reg [15:0] Adder_s, Adder_c, AdderOp;
    reg  [3:0] Carry_Prop, Carry_Gen;
    wire       CarryOut1, CarryOut2, CarryOut3, CarryOut;

    reg  [3:0] nC;


// 4-bit adder
function [3:0] Sum4;
    input [`C_Carry_Slice-1:0] Data;
    input [`C_Carry_Slice-2:0] Bit_Carry;
    input Carry;
    reg [3:0] C;
    begin
        C[0] = Carry;
        C[1] = Bit_Carry[0] | (Carry & Data[0]);
        C[2] = Bit_Carry[1] | (Bit_Carry[0] & Data[1]) | (Carry & Data[0] & Data[1]);
        C[3] = Bit_Carry[2] | (Bit_Carry[1] & Data[2]) | 
               (Bit_Carry[0] & Data[1] & Data[2]) | (Carry & Data[0] & Data[1] & Data[2]);
        Sum4 = {Data[3]^C[3], Data[2]^C[2], Data[1]^C[1], Data[0]^C[0]};
    end
endfunction


// Single-bit sum and carrys
always @(AdderIpA or AdderIpB)
begin
    Adder_s = AdderIpA ^ AdderIpB;
    Adder_c = AdderIpA & AdderIpB;
end

// 4-bit carry propagate/generate
always @(Adder_s or Adder_c)
    for (nC=0; nC<=3; nC=nC+1)
    begin
        Carry_Prop[nC] = Adder_s[nC*`C_Carry_Slice] & Adder_s[nC*`C_Carry_Slice+1] &
                        Adder_s[nC*`C_Carry_Slice+2] & Adder_s[nC*`C_Carry_Slice+3];
        Carry_Gen[nC] = (Adder_c[nC*`C_Carry_Slice] & Adder_s[nC*`C_Carry_Slice+1] &
                        Adder_s[nC*`C_Carry_Slice+2] & Adder_s[nC*`C_Carry_Slice+3]) |
                       (Adder_c[nC*`C_Carry_Slice+1] & Adder_s[nC*`C_Carry_Slice+2] &
                        Adder_s[nC*`C_Carry_Slice+3]) |
                       (Adder_c[nC*`C_Carry_Slice+2] & Adder_s[nC*`C_Carry_Slice+3]) |
                        Adder_c[nC*`C_Carry_Slice+3];
    end

// Look-ahead carries
m3s056ct U1 (CarryIn, Carry_Prop, Carry_Gen, CarryOut1, CarryOut2, CarryOut3, CarryOut);

// Add in carries
always @(Adder_s or Adder_c or CarryIn or CarryOut1 or CarryOut2 or CarryOut3)
begin
    AdderOp[3:0] = Sum4(Adder_s[3:0], Adder_c[2:0], CarryIn);
    AdderOp[7:4] = Sum4(Adder_s[7:4], Adder_c[6:4], CarryOut1);
    AdderOp[11:8] = Sum4(Adder_s[11:8], Adder_c[10:8], CarryOut2);
    AdderOp[15:12] = Sum4(Adder_s[15:12], Adder_c[14:12], CarryOut3);
end

endmodule