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//////////////////////////////////////////////////////////////////////
////                                                              ////
////  Versatile library, clock and reset                          ////
////                                                              ////
////  Description                                                 ////
////  Logic related to clock and reset                            ////
////                                                              ////
////                                                              ////
////  To Do:                                                      ////
////   - add more different registers                             ////
////                                                              ////
////  Author(s):                                                  ////
////      - Michael Unneback, unneback@opencores.org              ////
////        ORSoC AB                                              ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2010 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// 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. ////
////                                                              ////
//// This source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
// Global buffer
// usage:
// use to enable global buffers for high fan out signals such as clock and reset
//altera
 // ALTERA
 //ACTEL
// sync reset
// input active lo async reset, normally from external reset generator and/or switch
// output active high global reset sync with two DFFs 
`timescale 1 ns/100 ps
module vl_sync_rst ( rst_n_i, rst_o, clk);
input rst_n_i, clk;
output rst_o;
reg [1:0] tmp;
always @ (posedge clk or negedge rst_n_i)
if (!rst_n_i)
	tmp <= 2'b11;
else
	tmp <= {1'b0,tmp[0]};
vl_gbuf buf_i0( .i(tmp[0]), .o(rst_o));
endmodule
// vl_pll
 //altera
 //actel
//////////////////////////////////////////////////////////////////////
////                                                              ////
////  Versatile library, registers                                ////
////                                                              ////
////  Description                                                 ////
////  Different type of registers                                 ////
////                                                              ////
////                                                              ////
////  To Do:                                                      ////
////   - add more different registers                             ////
////                                                              ////
////  Author(s):                                                  ////
////      - Michael Unneback, unneback@opencores.org              ////
////        ORSoC AB                                              ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2010 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// 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. ////
////                                                              ////
//// This source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
module vl_dff ( d, q, clk, rst);
	parameter width = 1;	
	parameter reset_value = 0;
	input [width-1:0] d; 
	input clk, rst;
	output reg [width-1:0] q;
	always @ (posedge clk or posedge rst)
	if (rst)
		q <= reset_value;
	else
		q <= d;
endmodule
module vl_dff_array ( d, q, clk, rst);
	parameter width = 1;
        parameter depth = 2;
	parameter reset_value = 1'b0;
	input [width-1:0] d; 
	input clk, rst;
	output [width-1:0] q;
        reg  [0:depth-1] q_tmp [width-1:0];
	integer i;
	always @ (posedge clk or posedge rst)
	if (rst) begin
            for (i=0;i<depth;i=i+1)
		q_tmp[i] <= {width{reset_value}};
	end else begin
            q_tmp[0] <= d;
            for (i=1;i<depth;i=i+1)
		q_tmp[i] <= q_tmp[i-1];
        end
    assign q = q_tmp[depth-1];
endmodule
module vl_dff_ce ( d, ce, q, clk, rst);
	parameter width = 1;	
	parameter reset_value = 0;
	input [width-1:0] d; 
	input ce, clk, rst;
	output reg [width-1:0] q;
	always @ (posedge clk or posedge rst)
	if (rst)
		q <= reset_value;
	else
		if (ce)
			q <= d;
endmodule
module vl_dff_ce_clear ( d, ce, clear, q, clk, rst);
	parameter width = 1;	
	parameter reset_value = 0;
	input [width-1:0] d; 
	input ce, clear, clk, rst;
	output reg [width-1:0] q;
	always @ (posedge clk or posedge rst)
	if (rst)
	    q <= reset_value;
	else
            if (ce)
                if (clear)
                    q <= {width{1'b0}};
                else
                    q <= d;
endmodule
module vl_dff_ce_set ( d, ce, set, q, clk, rst);
	parameter width = 1;	
	parameter reset_value = 0;
	input [width-1:0] d; 
	input ce, set, clk, rst;
	output reg [width-1:0] q;
	always @ (posedge clk or posedge rst)
	if (rst)
	    q <= reset_value;
	else
            if (ce)
                if (set)
                    q <= {width{1'b1}};
                else
                    q <= d;
endmodule
// megafunction wizard: %LPM_FF%
// GENERATION: STANDARD
// VERSION: WM1.0
// MODULE: lpm_ff 
// ============================================================
// File Name: dff_sr.v
// Megafunction Name(s):
// 			lpm_ff
//
// Simulation Library Files(s):
// 			lpm
// ============================================================
// ************************************************************
// THIS IS A WIZARD-GENERATED FILE. DO NOT EDIT THIS FILE!
//
// 9.1 Build 304 01/25/2010 SP 1 SJ Full Version
// ************************************************************
//Copyright (C) 1991-2010 Altera Corporation
//Your use of Altera Corporation's design tools, logic functions 
//and other software and tools, and its AMPP partner logic 
//functions, and any output files from any of the foregoing 
//(including device programming or simulation files), and any 
//associated documentation or information are expressly subject 
//to the terms and conditions of the Altera Program License 
//Subscription Agreement, Altera MegaCore Function License 
//Agreement, or other applicable license agreement, including, 
//without limitation, that your use is for the sole purpose of 
//programming logic devices manufactured by Altera and sold by 
//Altera or its authorized distributors.  Please refer to the 
//applicable agreement for further details.
// synopsys translate_off
`timescale 1 ps / 1 ps
// synopsys translate_on
module vl_dff_sr (
	aclr,
	aset,
	clock,
	data,
	q);
	input	  aclr;
	input	  aset;
	input	  clock;
	input	  data;
	output	  q;
	wire [0:0] sub_wire0;
	wire [0:0] sub_wire1 = sub_wire0[0:0];
	wire  q = sub_wire1;
	wire  sub_wire2 = data;
	wire  sub_wire3 = sub_wire2;
	lpm_ff	lpm_ff_component (
				.aclr (aclr),
				.clock (clock),
				.data (sub_wire3),
				.aset (aset),
				.q (sub_wire0)
				// synopsys translate_off
				,
				.aload (),
				.enable (),
				.sclr (),
				.sload (),
				.sset ()
				// synopsys translate_on
				);
	defparam
		lpm_ff_component.lpm_fftype = "DFF",
		lpm_ff_component.lpm_type = "LPM_FF",
		lpm_ff_component.lpm_width = 1;
endmodule
// ============================================================
// CNX file retrieval info
// ============================================================
// Retrieval info: PRIVATE: ACLR NUMERIC "1"
// Retrieval info: PRIVATE: ALOAD NUMERIC "0"
// Retrieval info: PRIVATE: ASET NUMERIC "1"
// Retrieval info: PRIVATE: ASET_ALL1 NUMERIC "1"
// Retrieval info: PRIVATE: CLK_EN NUMERIC "0"
// Retrieval info: PRIVATE: DFF NUMERIC "1"
// Retrieval info: PRIVATE: INTENDED_DEVICE_FAMILY STRING "Cyclone IV E"
// Retrieval info: PRIVATE: SCLR NUMERIC "0"
// Retrieval info: PRIVATE: SLOAD NUMERIC "0"
// Retrieval info: PRIVATE: SSET NUMERIC "0"
// Retrieval info: PRIVATE: SSET_ALL1 NUMERIC "1"
// Retrieval info: PRIVATE: SYNTH_WRAPPER_GEN_POSTFIX STRING "0"
// Retrieval info: PRIVATE: UseTFFdataPort NUMERIC "0"
// Retrieval info: PRIVATE: nBit NUMERIC "1"
// Retrieval info: CONSTANT: LPM_FFTYPE STRING "DFF"
// Retrieval info: CONSTANT: LPM_TYPE STRING "LPM_FF"
// Retrieval info: CONSTANT: LPM_WIDTH NUMERIC "1"
// Retrieval info: USED_PORT: aclr 0 0 0 0 INPUT NODEFVAL aclr
// Retrieval info: USED_PORT: aset 0 0 0 0 INPUT NODEFVAL aset
// Retrieval info: USED_PORT: clock 0 0 0 0 INPUT NODEFVAL clock
// Retrieval info: USED_PORT: data 0 0 0 0 INPUT NODEFVAL data
// Retrieval info: USED_PORT: q 0 0 0 0 OUTPUT NODEFVAL q
// Retrieval info: CONNECT: @clock 0 0 0 0 clock 0 0 0 0
// Retrieval info: CONNECT: q 0 0 0 0 @q 0 0 1 0
// Retrieval info: CONNECT: @aclr 0 0 0 0 aclr 0 0 0 0
// Retrieval info: CONNECT: @aset 0 0 0 0 aset 0 0 0 0
// Retrieval info: CONNECT: @data 0 0 1 0 data 0 0 0 0
// Retrieval info: LIBRARY: lpm lpm.lpm_components.all
// Retrieval info: GEN_FILE: TYPE_NORMAL dff_sr.v TRUE
// Retrieval info: GEN_FILE: TYPE_NORMAL dff_sr.inc FALSE
// Retrieval info: GEN_FILE: TYPE_NORMAL dff_sr.cmp FALSE
// Retrieval info: GEN_FILE: TYPE_NORMAL dff_sr.bsf FALSE
// Retrieval info: GEN_FILE: TYPE_NORMAL dff_sr_inst.v FALSE
// Retrieval info: GEN_FILE: TYPE_NORMAL dff_sr_bb.v FALSE
// Retrieval info: LIB_FILE: lpm
// LATCH
// For targtes not supporting LATCH use dff_sr with clk=1 and data=1
module vl_latch ( d, le, q, clk);
input d, le;
output q;
input clk;
dff_sr i0 (.aclr(), .aset(), .clock(1'b1), .data(1'b1), .q(q));
endmodule
module vl_shreg ( d, q, clk, rst);
parameter depth = 10;
input d;
output q;
input clk, rst;
reg [1:depth] dffs;
always @ (posedge clk or posedge rst)
if (rst)
    dffs <= {depth{1'b0}};
else
    dffs <= {d,dffs[1:depth-1]};
assign q = dffs[depth];
endmodule
module vl_shreg_ce ( d, ce, q, clk, rst);
parameter depth = 10;
input d, ce;
output q;
input clk, rst;
reg [1:depth] dffs;
always @ (posedge clk or posedge rst)
if (rst)
    dffs <= {depth{1'b0}};
else
    if (ce)
        dffs <= {d,dffs[1:depth-1]};
assign q = dffs[depth];
endmodule
module vl_delay ( d, q, clk, rst);
parameter depth = 10;
input d;
output q;
input clk, rst;
reg [1:depth] dffs;
always @ (posedge clk or posedge rst)
if (rst)
    dffs <= {depth{1'b0}};
else
    dffs <= {d,dffs[1:depth-1]};
assign q = dffs[depth];
endmodule
module vl_delay_emptyflag ( d, q, emptyflag, clk, rst);
parameter depth = 10;
input d;
output q, emptyflag;
input clk, rst;
reg [1:depth] dffs;
always @ (posedge clk or posedge rst)
if (rst)
    dffs <= {depth{1'b0}};
else
    dffs <= {d,dffs[1:depth-1]};
assign q = dffs[depth];
assign emptyflag = !(|dffs);
endmodule
//////////////////////////////////////////////////////////////////////
////                                                              ////
////  Logic functions                                             ////
////                                                              ////
////  Description                                                 ////
////  Logic functions such as multiplexers                        ////
////                                                              ////
////                                                              ////
////  To Do:                                                      ////
////   -                                                          ////
////                                                              ////
////  Author(s):                                                  ////
////      - Michael Unneback, unneback@opencores.org              ////
////        ORSoC AB                                              ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2010 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// 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. ////
////                                                              ////
//// This source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
module vl_mux4_andor ( a3, a2, a1, a0, sel, dout);
parameter width = 32;
parameter nr_of_ports = 4;
input [width-1:0] a3, a2, a1, a0;
input [nr_of_ports-1:0] sel;
output [width-1:0] dout;
wire [width-1:0] tmp [nr_of_ports-1:0];
integer i;
// and
assign tmp[0] = {width{sel[0]}} & a0;
assign tmp[1] = {width{sel[1]}} & a1;
assign tmp[2] = {width{sel[2]}} & a2;
assign tmp[3] = {width{sel[3]}} & a3;
// or
assign dout = tmp[3] | tmp[2] | tmp[1] | tmp[0];
endmodule
module vl_mux5_andor ( a4, a3, a2, a1, a0, sel, dout);
parameter width = 32;
parameter nr_of_ports = 5;
input [width-1:0] a4, a3, a2, a1, a0;
input [nr_of_ports-1:0] sel;
output [width-1:0] dout;
wire [width-1:0] tmp [nr_of_ports-1:0];
integer i;
// and
assign tmp[0] = {width{sel[0]}} & a0;
assign tmp[1] = {width{sel[1]}} & a1;
assign tmp[2] = {width{sel[2]}} & a2;
assign tmp[3] = {width{sel[3]}} & a3;
assign tmp[4] = {width{sel[4]}} & a4;
// or
assign dout = tmp[4] | tmp[3] | tmp[2] | tmp[1] | tmp[0];
endmodule
module vl_mux6_andor ( a5, a4, a3, a2, a1, a0, sel, dout);
parameter width = 32;
parameter nr_of_ports = 6;
input [width-1:0] a5, a4, a3, a2, a1, a0;
input [nr_of_ports-1:0] sel;
output [width-1:0] dout;
wire [width-1:0] tmp [nr_of_ports-1:0];
integer i;
// and
assign tmp[0] = {width{sel[0]}} & a0;
assign tmp[1] = {width{sel[1]}} & a1;
assign tmp[2] = {width{sel[2]}} & a2;
assign tmp[3] = {width{sel[3]}} & a3;
assign tmp[4] = {width{sel[4]}} & a4;
assign tmp[5] = {width{sel[5]}} & a5;
// or
assign dout = tmp[5] | tmp[4] | tmp[3] | tmp[2] | tmp[1] | tmp[0];
endmodule
//////////////////////////////////////////////////////////////////////
////                                                              ////
////  Versatile counter                                           ////
////                                                              ////
////  Description                                                 ////
////  Versatile counter, a reconfigurable binary, gray or LFSR    ////
////  counter                                                     ////
////                                                              ////
////  To Do:                                                      ////
////   - add LFSR with more taps                                  ////
////                                                              ////
////  Author(s):                                                  ////
////      - Michael Unneback, unneback@opencores.org              ////
////        ORSoC AB                                              ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2009 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// 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. ////
////                                                              ////
//// This source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
// binary counter
module vl_cnt_bin ( q, rst, clk);
   parameter length = 4;
   output [length:1] q;
   input rst;
   input clk;
   parameter clear_value = 0;
   parameter set_value = 1;
   parameter wrap_value = 0;
   parameter level1_value = 15;
   reg  [length:1] qi;
   wire [length:1] q_next;
   assign q_next = qi + {{length-1{1'b0}},1'b1};
   always @ (posedge clk or posedge rst)
     if (rst)
       qi <= {length{1'b0}};
     else
       qi <= q_next;
   assign q = qi;
endmodule
//////////////////////////////////////////////////////////////////////
////                                                              ////
////  Versatile counter                                           ////
////                                                              ////
////  Description                                                 ////
////  Versatile counter, a reconfigurable binary, gray or LFSR    ////
////  counter                                                     ////
////                                                              ////
////  To Do:                                                      ////
////   - add LFSR with more taps                                  ////
////                                                              ////
////  Author(s):                                                  ////
////      - Michael Unneback, unneback@opencores.org              ////
////        ORSoC AB                                              ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2009 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// 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. ////
////                                                              ////
//// This source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
// binary counter
module vl_cnt_bin_clear ( clear, q, rst, clk);
   parameter length = 4;
   input clear;
   output [length:1] q;
   input rst;
   input clk;
   parameter clear_value = 0;
   parameter set_value = 1;
   parameter wrap_value = 0;
   parameter level1_value = 15;
   reg  [length:1] qi;
   wire [length:1] q_next;
   assign q_next =  clear ? {length{1'b0}} :qi + {{length-1{1'b0}},1'b1};
   always @ (posedge clk or posedge rst)
     if (rst)
       qi <= {length{1'b0}};
     else
       qi <= q_next;
   assign q = qi;
endmodule
//////////////////////////////////////////////////////////////////////
////                                                              ////
////  Versatile counter                                           ////
////                                                              ////
////  Description                                                 ////
////  Versatile counter, a reconfigurable binary, gray or LFSR    ////
////  counter                                                     ////
////                                                              ////
////  To Do:                                                      ////
////   - add LFSR with more taps                                  ////
////                                                              ////
////  Author(s):                                                  ////
////      - Michael Unneback, unneback@opencores.org              ////
////        ORSoC AB                                              ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2009 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// 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. ////
////                                                              ////
//// This source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
// binary counter
module vl_cnt_bin_ce ( cke, q, rst, clk);
   parameter length = 4;
   input cke;
   output [length:1] q;
   input rst;
   input clk;
   parameter clear_value = 0;
   parameter set_value = 1;
   parameter wrap_value = 0;
   parameter level1_value = 15;
   reg  [length:1] qi;
   wire [length:1] q_next;
   assign q_next = qi + {{length-1{1'b0}},1'b1};
   always @ (posedge clk or posedge rst)
     if (rst)
       qi <= {length{1'b0}};
     else
     if (cke)
       qi <= q_next;
   assign q = qi;
endmodule
//////////////////////////////////////////////////////////////////////
////                                                              ////
////  Versatile counter                                           ////
////                                                              ////
////  Description                                                 ////
////  Versatile counter, a reconfigurable binary, gray or LFSR    ////
////  counter                                                     ////
////                                                              ////
////  To Do:                                                      ////
////   - add LFSR with more taps                                  ////
////                                                              ////
////  Author(s):                                                  ////
////      - Michael Unneback, unneback@opencores.org              ////
////        ORSoC AB                                              ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2009 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// 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. ////
////                                                              ////
//// This source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
// binary counter
module vl_cnt_bin_ce_clear ( clear, cke, q, rst, clk);
   parameter length = 4;
   input clear;
   input cke;
   output [length:1] q;
   input rst;
   input clk;
   parameter clear_value = 0;
   parameter set_value = 1;
   parameter wrap_value = 0;
   parameter level1_value = 15;
   reg  [length:1] qi;
   wire [length:1] q_next;
   assign q_next =  clear ? {length{1'b0}} :qi + {{length-1{1'b0}},1'b1};
   always @ (posedge clk or posedge rst)
     if (rst)
       qi <= {length{1'b0}};
     else
     if (cke)
       qi <= q_next;
   assign q = qi;
endmodule
//////////////////////////////////////////////////////////////////////
////                                                              ////
////  Versatile counter                                           ////
////                                                              ////
////  Description                                                 ////
////  Versatile counter, a reconfigurable binary, gray or LFSR    ////
////  counter                                                     ////
////                                                              ////
////  To Do:                                                      ////
////   - add LFSR with more taps                                  ////
////                                                              ////
////  Author(s):                                                  ////
////      - Michael Unneback, unneback@opencores.org              ////
////        ORSoC AB                                              ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2009 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// 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. ////
////                                                              ////
//// This source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
// binary counter
module vl_cnt_bin_ce_clear_set_rew ( clear, set, cke, rew, q, rst, clk);
   parameter length = 4;
   input clear;
   input set;
   input cke;
   input rew;
   output [length:1] q;
   input rst;
   input clk;
   parameter clear_value = 0;
   parameter set_value = 1;
   parameter wrap_value = 0;
   parameter level1_value = 15;
   reg  [length:1] qi;
   wire  [length:1] q_next, q_next_fw, q_next_rew;
   assign q_next_fw  =  clear ? {length{1'b0}} : set ? set_value :qi + {{length-1{1'b0}},1'b1};
   assign q_next_rew =  clear ? clear_value : set ? set_value :qi - {{length-1{1'b0}},1'b1};
   assign q_next = rew ? q_next_rew : q_next_fw;
   always @ (posedge clk or posedge rst)
     if (rst)
       qi <= {length{1'b0}};
     else
     if (cke)
       qi <= q_next;
   assign q = qi;
endmodule
//////////////////////////////////////////////////////////////////////
////                                                              ////
////  Versatile counter                                           ////
////                                                              ////
////  Description                                                 ////
////  Versatile counter, a reconfigurable binary, gray or LFSR    ////
////  counter                                                     ////
////                                                              ////
////  To Do:                                                      ////
////   - add LFSR with more taps                                  ////
////                                                              ////
////  Author(s):                                                  ////
////      - Michael Unneback, unneback@opencores.org              ////
////        ORSoC AB                                              ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2009 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// 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. ////
////                                                              ////
//// This source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
// binary counter
module vl_cnt_bin_ce_rew_l1 ( cke, rew, level1, rst, clk);
   parameter length = 4;
   input cke;
   input rew;
   output reg level1;
   input rst;
   input clk;
   parameter clear_value = 0;
   parameter set_value = 1;
   parameter wrap_value = 1;
   parameter level1_value = 15;
   reg  [length:1] qi;
   wire  [length:1] q_next, q_next_fw, q_next_rew;
   assign q_next_fw  = qi + {{length-1{1'b0}},1'b1};
   assign q_next_rew = qi - {{length-1{1'b0}},1'b1};
   assign q_next = rew ? q_next_rew : q_next_fw;
   always @ (posedge clk or posedge rst)
     if (rst)
       qi <= {length{1'b0}};
     else
     if (cke)
       qi <= q_next;
    always @ (posedge clk or posedge rst)
    if (rst)
        level1 <= 1'b0;
    else
    if (cke)
    if (q_next == level1_value)
        level1 <= 1'b1;
    else if (qi == level1_value & rew)
        level1 <= 1'b0;
endmodule
//////////////////////////////////////////////////////////////////////
////                                                              ////
////  Versatile counter                                           ////
////                                                              ////
////  Description                                                 ////
////  Versatile counter, a reconfigurable binary, gray or LFSR    ////
////  counter                                                     ////
////                                                              ////
////  To Do:                                                      ////
////   - add LFSR with more taps                                  ////
////                                                              ////
////  Author(s):                                                  ////
////      - Michael Unneback, unneback@opencores.org              ////
////        ORSoC AB                                              ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2009 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// 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. ////
////                                                              ////
//// This source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
// LFSR counter
module vl_cnt_lfsr_zq ( zq, rst, clk);
   parameter length = 4;
   output reg zq;
   input rst;
   input clk;
   parameter clear_value = 0;
   parameter set_value = 1;
   parameter wrap_value = 8;
   parameter level1_value = 15;
   reg  [length:1] qi;
   reg lfsr_fb;
   wire [length:1] q_next;
   reg [32:1] polynom;
   integer i;
   always @ (qi)
   begin
        case (length) 
         2: polynom = 32'b11;                               // 0x3
         3: polynom = 32'b110;                              // 0x6
         4: polynom = 32'b1100;                             // 0xC
         5: polynom = 32'b10100;                            // 0x14
         6: polynom = 32'b110000;                           // 0x30
         7: polynom = 32'b1100000;                          // 0x60
         8: polynom = 32'b10111000;                         // 0xb8
         9: polynom = 32'b100010000;                        // 0x110
        10: polynom = 32'b1001000000;                       // 0x240
        11: polynom = 32'b10100000000;                      // 0x500
        12: polynom = 32'b100000101001;                     // 0x829
        13: polynom = 32'b1000000001100;                    // 0x100C
        14: polynom = 32'b10000000010101;                   // 0x2015
        15: polynom = 32'b110000000000000;                  // 0x6000
        16: polynom = 32'b1101000000001000;                 // 0xD008
        17: polynom = 32'b10010000000000000;                // 0x12000
        18: polynom = 32'b100000010000000000;               // 0x20400
        19: polynom = 32'b1000000000000100011;              // 0x40023
        20: polynom = 32'b10000010000000000000;             // 0x82000
        21: polynom = 32'b101000000000000000000;            // 0x140000
        22: polynom = 32'b1100000000000000000000;           // 0x300000
        23: polynom = 32'b10000100000000000000000;          // 0x420000
        24: polynom = 32'b111000010000000000000000;         // 0xE10000
        25: polynom = 32'b1001000000000000000000000;        // 0x1200000
        26: polynom = 32'b10000000000000000000100011;       // 0x2000023
        27: polynom = 32'b100000000000000000000010011;      // 0x4000013
        28: polynom = 32'b1100100000000000000000000000;     // 0xC800000
        29: polynom = 32'b10100000000000000000000000000;    // 0x14000000
        30: polynom = 32'b100000000000000000000000101001;   // 0x20000029
        31: polynom = 32'b1001000000000000000000000000000;  // 0x48000000
        32: polynom = 32'b10000000001000000000000000000011; // 0x80200003
        default: polynom = 32'b0;
        endcase
        lfsr_fb = qi[length];
        for (i=length-1; i>=1; i=i-1) begin
            if (polynom[i])
                lfsr_fb = lfsr_fb  ~^ qi[i];
        end
    end
   assign q_next = (qi == wrap_value) ? {length{1'b0}} :{qi[length-1:1],lfsr_fb};
   always @ (posedge clk or posedge rst)
     if (rst)
       qi <= {length{1'b0}};
     else
       qi <= q_next;
   always @ (posedge clk or posedge rst)
     if (rst)
       zq <= 1'b1;
     else
       zq <= q_next == {length{1'b0}};
endmodule
//////////////////////////////////////////////////////////////////////
////                                                              ////
////  Versatile counter                                           ////
////                                                              ////
////  Description                                                 ////
////  Versatile counter, a reconfigurable binary, gray or LFSR    ////
////  counter                                                     ////
////                                                              ////
////  To Do:                                                      ////
////   - add LFSR with more taps                                  ////
////                                                              ////
////  Author(s):                                                  ////
////      - Michael Unneback, unneback@opencores.org              ////
////        ORSoC AB                                              ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2009 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// 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. ////
////                                                              ////
//// This source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
// LFSR counter
module vl_cnt_lfsr_ce_zq ( cke, zq, rst, clk);
   parameter length = 4;
   input cke;
   output reg zq;
   input rst;
   input clk;
   parameter clear_value = 0;
   parameter set_value = 1;
   parameter wrap_value = 8;
   parameter level1_value = 15;
   reg  [length:1] qi;
   reg lfsr_fb;
   wire [length:1] q_next;
   reg [32:1] polynom;
   integer i;
   always @ (qi)
   begin
        case (length) 
         2: polynom = 32'b11;                               // 0x3
         3: polynom = 32'b110;                              // 0x6
         4: polynom = 32'b1100;                             // 0xC
         5: polynom = 32'b10100;                            // 0x14
         6: polynom = 32'b110000;                           // 0x30
         7: polynom = 32'b1100000;                          // 0x60
         8: polynom = 32'b10111000;                         // 0xb8
         9: polynom = 32'b100010000;                        // 0x110
        10: polynom = 32'b1001000000;                       // 0x240
        11: polynom = 32'b10100000000;                      // 0x500
        12: polynom = 32'b100000101001;                     // 0x829
        13: polynom = 32'b1000000001100;                    // 0x100C
        14: polynom = 32'b10000000010101;                   // 0x2015
        15: polynom = 32'b110000000000000;                  // 0x6000
        16: polynom = 32'b1101000000001000;                 // 0xD008
        17: polynom = 32'b10010000000000000;                // 0x12000
        18: polynom = 32'b100000010000000000;               // 0x20400
        19: polynom = 32'b1000000000000100011;              // 0x40023
        20: polynom = 32'b10000010000000000000;             // 0x82000
        21: polynom = 32'b101000000000000000000;            // 0x140000
        22: polynom = 32'b1100000000000000000000;           // 0x300000
        23: polynom = 32'b10000100000000000000000;          // 0x420000
        24: polynom = 32'b111000010000000000000000;         // 0xE10000
        25: polynom = 32'b1001000000000000000000000;        // 0x1200000
        26: polynom = 32'b10000000000000000000100011;       // 0x2000023
        27: polynom = 32'b100000000000000000000010011;      // 0x4000013
        28: polynom = 32'b1100100000000000000000000000;     // 0xC800000
        29: polynom = 32'b10100000000000000000000000000;    // 0x14000000
        30: polynom = 32'b100000000000000000000000101001;   // 0x20000029
        31: polynom = 32'b1001000000000000000000000000000;  // 0x48000000
        32: polynom = 32'b10000000001000000000000000000011; // 0x80200003
        default: polynom = 32'b0;
        endcase
        lfsr_fb = qi[length];
        for (i=length-1; i>=1; i=i-1) begin
            if (polynom[i])
                lfsr_fb = lfsr_fb  ~^ qi[i];
        end
    end
   assign q_next = (qi == wrap_value) ? {length{1'b0}} :{qi[length-1:1],lfsr_fb};
   always @ (posedge clk or posedge rst)
     if (rst)
       qi <= {length{1'b0}};
     else
     if (cke)
       qi <= q_next;
   always @ (posedge clk or posedge rst)
     if (rst)
       zq <= 1'b1;
     else
     if (cke)
       zq <= q_next == {length{1'b0}};
endmodule
//////////////////////////////////////////////////////////////////////
////                                                              ////
////  Versatile counter                                           ////
////                                                              ////
////  Description                                                 ////
////  Versatile counter, a reconfigurable binary, gray or LFSR    ////
////  counter                                                     ////
////                                                              ////
////  To Do:                                                      ////
////   - add LFSR with more taps                                  ////
////                                                              ////
////  Author(s):                                                  ////
////      - Michael Unneback, unneback@opencores.org              ////
////        ORSoC AB                                              ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2009 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// 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. ////
////                                                              ////
//// This source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
// LFSR counter
module vl_cnt_lfsr_ce_q_zq ( cke, q, zq, rst, clk);
   parameter length = 4;
   input cke;
   output [length:1] q;
   output reg zq;
   input rst;
   input clk;
   parameter clear_value = 0;
   parameter set_value = 1;
   parameter wrap_value = 8;
   parameter level1_value = 15;
   reg  [length:1] qi;
   reg lfsr_fb;
   wire [length:1] q_next;
   reg [32:1] polynom;
   integer i;
   always @ (qi)
   begin
        case (length) 
         2: polynom = 32'b11;                               // 0x3
         3: polynom = 32'b110;                              // 0x6
         4: polynom = 32'b1100;                             // 0xC
         5: polynom = 32'b10100;                            // 0x14
         6: polynom = 32'b110000;                           // 0x30
         7: polynom = 32'b1100000;                          // 0x60
         8: polynom = 32'b10111000;                         // 0xb8
         9: polynom = 32'b100010000;                        // 0x110
        10: polynom = 32'b1001000000;                       // 0x240
        11: polynom = 32'b10100000000;                      // 0x500
        12: polynom = 32'b100000101001;                     // 0x829
        13: polynom = 32'b1000000001100;                    // 0x100C
        14: polynom = 32'b10000000010101;                   // 0x2015
        15: polynom = 32'b110000000000000;                  // 0x6000
        16: polynom = 32'b1101000000001000;                 // 0xD008
        17: polynom = 32'b10010000000000000;                // 0x12000
        18: polynom = 32'b100000010000000000;               // 0x20400
        19: polynom = 32'b1000000000000100011;              // 0x40023
        20: polynom = 32'b10000010000000000000;             // 0x82000
        21: polynom = 32'b101000000000000000000;            // 0x140000
        22: polynom = 32'b1100000000000000000000;           // 0x300000
        23: polynom = 32'b10000100000000000000000;          // 0x420000
        24: polynom = 32'b111000010000000000000000;         // 0xE10000
        25: polynom = 32'b1001000000000000000000000;        // 0x1200000
        26: polynom = 32'b10000000000000000000100011;       // 0x2000023
        27: polynom = 32'b100000000000000000000010011;      // 0x4000013
        28: polynom = 32'b1100100000000000000000000000;     // 0xC800000
        29: polynom = 32'b10100000000000000000000000000;    // 0x14000000
        30: polynom = 32'b100000000000000000000000101001;   // 0x20000029
        31: polynom = 32'b1001000000000000000000000000000;  // 0x48000000
        32: polynom = 32'b10000000001000000000000000000011; // 0x80200003
        default: polynom = 32'b0;
        endcase
        lfsr_fb = qi[length];
        for (i=length-1; i>=1; i=i-1) begin
            if (polynom[i])
                lfsr_fb = lfsr_fb  ~^ qi[i];
        end
    end
   assign q_next = (qi == wrap_value) ? {length{1'b0}} :{qi[length-1:1],lfsr_fb};
   always @ (posedge clk or posedge rst)
     if (rst)
       qi <= {length{1'b0}};
     else
     if (cke)
       qi <= q_next;
   assign q = qi;
   always @ (posedge clk or posedge rst)
     if (rst)
       zq <= 1'b1;
     else
     if (cke)
       zq <= q_next == {length{1'b0}};
endmodule
//////////////////////////////////////////////////////////////////////
////                                                              ////
////  Versatile counter                                           ////
////                                                              ////
////  Description                                                 ////
////  Versatile counter, a reconfigurable binary, gray or LFSR    ////
////  counter                                                     ////
////                                                              ////
////  To Do:                                                      ////
////   - add LFSR with more taps                                  ////
////                                                              ////
////  Author(s):                                                  ////
////      - Michael Unneback, unneback@opencores.org              ////
////        ORSoC AB                                              ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2009 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// 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. ////
////                                                              ////
//// This source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
// LFSR counter
module vl_cnt_lfsr_ce_rew_l1 ( cke, rew, level1, rst, clk);
   parameter length = 4;
   input cke;
   input rew;
   output reg level1;
   input rst;
   input clk;
   parameter clear_value = 0;
   parameter set_value = 1;
   parameter wrap_value = 8;
   parameter level1_value = 15;
   reg  [length:1] qi;
   reg lfsr_fb, lfsr_fb_rew;
   wire  [length:1] q_next, q_next_fw, q_next_rew;
   reg [32:1] polynom_rew;
   integer j;
   reg [32:1] polynom;
   integer i;
   always @ (qi)
   begin
        case (length) 
         2: polynom = 32'b11;                               // 0x3
         3: polynom = 32'b110;                              // 0x6
         4: polynom = 32'b1100;                             // 0xC
         5: polynom = 32'b10100;                            // 0x14
         6: polynom = 32'b110000;                           // 0x30
         7: polynom = 32'b1100000;                          // 0x60
         8: polynom = 32'b10111000;                         // 0xb8
         9: polynom = 32'b100010000;                        // 0x110
        10: polynom = 32'b1001000000;                       // 0x240
        11: polynom = 32'b10100000000;                      // 0x500
        12: polynom = 32'b100000101001;                     // 0x829
        13: polynom = 32'b1000000001100;                    // 0x100C
        14: polynom = 32'b10000000010101;                   // 0x2015
        15: polynom = 32'b110000000000000;                  // 0x6000
        16: polynom = 32'b1101000000001000;                 // 0xD008
        17: polynom = 32'b10010000000000000;                // 0x12000
        18: polynom = 32'b100000010000000000;               // 0x20400
        19: polynom = 32'b1000000000000100011;              // 0x40023
        20: polynom = 32'b10000010000000000000;             // 0x82000
        21: polynom = 32'b101000000000000000000;            // 0x140000
        22: polynom = 32'b1100000000000000000000;           // 0x300000
        23: polynom = 32'b10000100000000000000000;          // 0x420000
        24: polynom = 32'b111000010000000000000000;         // 0xE10000
        25: polynom = 32'b1001000000000000000000000;        // 0x1200000
        26: polynom = 32'b10000000000000000000100011;       // 0x2000023
        27: polynom = 32'b100000000000000000000010011;      // 0x4000013
        28: polynom = 32'b1100100000000000000000000000;     // 0xC800000
        29: polynom = 32'b10100000000000000000000000000;    // 0x14000000
        30: polynom = 32'b100000000000000000000000101001;   // 0x20000029
        31: polynom = 32'b1001000000000000000000000000000;  // 0x48000000
        32: polynom = 32'b10000000001000000000000000000011; // 0x80200003
        default: polynom = 32'b0;
        endcase
        lfsr_fb = qi[length];
        for (i=length-1; i>=1; i=i-1) begin
            if (polynom[i])
                lfsr_fb = lfsr_fb  ~^ qi[i];
        end
    end
   assign q_next_fw  = (qi == wrap_value) ? {length{1'b0}} :{qi[length-1:1],lfsr_fb};
   always @ (qi)
   begin
        case (length) 
         2: polynom_rew = 32'b11;
         3: polynom_rew = 32'b110;
         4: polynom_rew = 32'b1100;
         5: polynom_rew = 32'b10100;
         6: polynom_rew = 32'b110000;
         7: polynom_rew = 32'b1100000;
         8: polynom_rew = 32'b10111000;
         9: polynom_rew = 32'b100010000;
        10: polynom_rew = 32'b1001000000;
        11: polynom_rew = 32'b10100000000;
        12: polynom_rew = 32'b100000101001;
        13: polynom_rew = 32'b1000000001100;
        14: polynom_rew = 32'b10000000010101;
        15: polynom_rew = 32'b110000000000000;
        16: polynom_rew = 32'b1101000000001000;
        17: polynom_rew = 32'b10010000000000000;
        18: polynom_rew = 32'b100000010000000000;
        19: polynom_rew = 32'b1000000000000100011;
        20: polynom_rew = 32'b10000010000000000000;
        21: polynom_rew = 32'b101000000000000000000;
        22: polynom_rew = 32'b1100000000000000000000;
        23: polynom_rew = 32'b10000100000000000000000;
        24: polynom_rew = 32'b111000010000000000000000;
        25: polynom_rew = 32'b1001000000000000000000000;
        26: polynom_rew = 32'b10000000000000000000100011;
        27: polynom_rew = 32'b100000000000000000000010011;
        28: polynom_rew = 32'b1100100000000000000000000000;
        29: polynom_rew = 32'b10100000000000000000000000000;
        30: polynom_rew = 32'b100000000000000000000000101001;
        31: polynom_rew = 32'b1001000000000000000000000000000;
        32: polynom_rew = 32'b10000000001000000000000000000011;
        default: polynom_rew = 32'b0;
        endcase
        // rotate left
        polynom_rew[length:1] = { polynom_rew[length-2:1],polynom_rew[length] };
        lfsr_fb_rew = qi[length];
        for (i=length-1; i>=1; i=i-1) begin
            if (polynom_rew[i])
                lfsr_fb_rew = lfsr_fb_rew  ~^ qi[i];
        end
    end
   assign q_next_rew = (qi == wrap_value) ? {length{1'b0}} :{lfsr_fb_rew,qi[length:2]};
   assign q_next = rew ? q_next_rew : q_next_fw;
   always @ (posedge clk or posedge rst)
     if (rst)
       qi <= {length{1'b0}};
     else
     if (cke)
       qi <= q_next;
    always @ (posedge clk or posedge rst)
    if (rst)
        level1 <= 1'b0;
    else
    if (cke)
    if (q_next == level1_value)
        level1 <= 1'b1;
    else if (qi == level1_value & rew)
        level1 <= 1'b0;
endmodule
//////////////////////////////////////////////////////////////////////
////                                                              ////
////  Versatile counter                                           ////
////                                                              ////
////  Description                                                 ////
////  Versatile counter, a reconfigurable binary, gray or LFSR    ////
////  counter                                                     ////
////                                                              ////
////  To Do:                                                      ////
////   - add LFSR with more taps                                  ////
////                                                              ////
////  Author(s):                                                  ////
////      - Michael Unneback, unneback@opencores.org              ////
////        ORSoC AB                                              ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2009 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// 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. ////
////                                                              ////
//// This source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
// GRAY counter
module vl_cnt_gray ( q, rst, clk);
   parameter length = 4;
   output reg [length:1] q;
   input rst;
   input clk;
   parameter clear_value = 0;
   parameter set_value = 1;
   parameter wrap_value = 8;
   parameter level1_value = 15;
   reg  [length:1] qi;
   wire [length:1] q_next;
   assign q_next = qi + {{length-1{1'b0}},1'b1};
   always @ (posedge clk or posedge rst)
     if (rst)
       qi <= {length{1'b0}};
     else
       qi <= q_next;
   always @ (posedge clk or posedge rst)
     if (rst)
       q <= {length{1'b0}};
     else
         q <= (q_next>>1) ^ q_next;
endmodule
//////////////////////////////////////////////////////////////////////
////                                                              ////
////  Versatile counter                                           ////
////                                                              ////
////  Description                                                 ////
////  Versatile counter, a reconfigurable binary, gray or LFSR    ////
////  counter                                                     ////
////                                                              ////
////  To Do:                                                      ////
////   - add LFSR with more taps                                  ////
////                                                              ////
////  Author(s):                                                  ////
////      - Michael Unneback, unneback@opencores.org              ////
////        ORSoC AB                                              ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2009 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// 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. ////
////                                                              ////
//// This source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
// GRAY counter
module vl_cnt_gray_ce ( cke, q, rst, clk);
   parameter length = 4;
   input cke;
   output reg [length:1] q;
   input rst;
   input clk;
   parameter clear_value = 0;
   parameter set_value = 1;
   parameter wrap_value = 8;
   parameter level1_value = 15;
   reg  [length:1] qi;
   wire [length:1] q_next;
   assign q_next = qi + {{length-1{1'b0}},1'b1};
   always @ (posedge clk or posedge rst)
     if (rst)
       qi <= {length{1'b0}};
     else
     if (cke)
       qi <= q_next;
   always @ (posedge clk or posedge rst)
     if (rst)
       q <= {length{1'b0}};
     else
       if (cke)
         q <= (q_next>>1) ^ q_next;
endmodule
//////////////////////////////////////////////////////////////////////
////                                                              ////
////  Versatile counter                                           ////
////                                                              ////
////  Description                                                 ////
////  Versatile counter, a reconfigurable binary, gray or LFSR    ////
////  counter                                                     ////
////                                                              ////
////  To Do:                                                      ////
////   - add LFSR with more taps                                  ////
////                                                              ////
////  Author(s):                                                  ////
////      - Michael Unneback, unneback@opencores.org              ////
////        ORSoC AB                                              ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2009 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// 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. ////
////                                                              ////
//// This source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
// GRAY counter
module vl_cnt_gray_ce_bin ( cke, q, q_bin, rst, clk);
   parameter length = 4;
   input cke;
   output reg [length:1] q;
   output [length:1] q_bin;
   input rst;
   input clk;
   parameter clear_value = 0;
   parameter set_value = 1;
   parameter wrap_value = 8;
   parameter level1_value = 15;
   reg  [length:1] qi;
   wire [length:1] q_next;
   assign q_next = qi + {{length-1{1'b0}},1'b1};
   always @ (posedge clk or posedge rst)
     if (rst)
       qi <= {length{1'b0}};
     else
     if (cke)
       qi <= q_next;
   always @ (posedge clk or posedge rst)
     if (rst)
       q <= {length{1'b0}};
     else
       if (cke)
         q <= (q_next>>1) ^ q_next;
   assign q_bin = qi;
endmodule
//////////////////////////////////////////////////////////////////////
////                                                              ////
////  Versatile library, counters                                 ////
////                                                              ////
////  Description                                                 ////
////  counters                                                    ////
////                                                              ////
////                                                              ////
////  To Do:                                                      ////
////   - add more counters                                        ////
////                                                              ////
////  Author(s):                                                  ////
////      - Michael Unneback, unneback@opencores.org              ////
////        ORSoC AB                                              ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2010 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// 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. ////
////                                                              ////
//// This source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
module vl_cnt_shreg_wrap ( q, rst, clk);
   parameter length = 4;
   output reg [0:length-1] q;
   input rst;
   input clk;
    always @ (posedge clk or posedge rst)
    if (rst)
        q <= {1'b1,{length-1{1'b0}}};
    else
        q <= {q[length-1],q[0:length-2]};
endmodule
module vl_cnt_shreg_ce_wrap ( cke, q, rst, clk);
   parameter length = 4;
   input cke;
   output reg [0:length-1] q;
   input rst;
   input clk;
    always @ (posedge clk or posedge rst)
    if (rst)
        q <= {1'b1,{length-1{1'b0}}};
    else
        if (cke)
            q <= {q[length-1],q[0:length-2]};
endmodule
module vl_cnt_shreg_ce_clear ( cke, clear, q, rst, clk);
   parameter length = 4;
   input cke, clear;
   output reg [0:length-1] q;
   input rst;
   input clk;
    always @ (posedge clk or posedge rst)
    if (rst)
        q <= {1'b1,{length-1{1'b0}}};
    else
        if (cke)
            if (clear)
                q <= {1'b1,{length-1{1'b0}}};
            else
                q <= q >> 1;
endmodule
module vl_cnt_shreg_ce_clear_wrap ( cke, clear, q, rst, clk);
   parameter length = 4;
   input cke, clear;
   output reg [0:length-1] q;
   input rst;
   input clk;
    always @ (posedge clk or posedge rst)
    if (rst)
        q <= {1'b1,{length-1{1'b0}}};
    else
        if (cke)
            if (clear)
                q <= {1'b1,{length-1{1'b0}}};
            else
            q <= {q[length-1],q[0:length-2]};
endmodule
//////////////////////////////////////////////////////////////////////
////                                                              ////
////  Versatile library, memories                                 ////
////                                                              ////
////  Description                                                 ////
////  memories                                                    ////
////                                                              ////
////                                                              ////
////  To Do:                                                      ////
////   - add more memory types                                    ////
////                                                              ////
////  Author(s):                                                  ////
////      - Michael Unneback, unneback@opencores.org              ////
////        ORSoC AB                                              ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2010 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// 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. ////
////                                                              ////
//// This source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
/// ROM
module vl_rom_init ( adr, q, clk);
   parameter data_width = 32;
   parameter addr_width = 8;
   input [(addr_width-1):0] 	 adr;
   output reg [(data_width-1):0] q;
   input 			 clk;
   reg [data_width-1:0] rom [(1<<addr_width)-1:0];
   parameter memory_file = "vl_rom.vmem";
   initial
     begin
	$readmemh(memory_file, rom);
     end
   always @ (posedge clk)
     q <= rom[adr];
endmodule
/*
module vl_rom ( adr, q, clk);
parameter data_width = 32;
parameter addr_width = 4;
parameter [0:1>>addr_width-1] data [data_width-1:0] = {
    {32'h18000000},
    {32'hA8200000},
    {32'hA8200000},
    {32'hA8200000},
    {32'h44003000},
    {32'h15000000},
    {32'h15000000},
    {32'h15000000},
    {32'h15000000},
    {32'h15000000},
    {32'h15000000},
    {32'h15000000},
    {32'h15000000},
    {32'h15000000},
    {32'h15000000},
    {32'h15000000}};
input [addr_width-1:0] adr;
output reg [data_width-1:0] q;
input clk;
always @ (posedge clk)
    q <= data[adr];
endmodule
*/
// Single port RAM
module vl_ram ( d, adr, we, q, clk);
   parameter data_width = 32;
   parameter addr_width = 8;
   input [(data_width-1):0]      d;
   input [(addr_width-1):0] 	 adr;
   input 			 we;
   output reg [(data_width-1):0] q;
   input 			 clk;
   reg [data_width-1:0] ram [(1<<addr_width)-1:0];
   parameter init = 0;
   parameter memory_file = "vl_ram.vmem";
   generate if (init) begin : init_mem
   initial
     begin
	$readmemh(memory_file, ram);
     end
   end
   endgenerate 
   always @ (posedge clk)
   begin
   if (we)
     ram[adr] <= d;
   q <= ram[adr];
   end
endmodule
module vl_ram_be ( d, adr, be, we, q, clk);
   parameter data_width = 32;
   parameter addr_width = 8;
   input [(data_width-1):0]      d;
   input [(addr_width-1):0] 	 adr;
   input [(addr_width/4)-1:0]    be;
   input 			 we;
   output reg [(data_width-1):0] q;
   input 			 clk;
   reg [data_width-1:0] ram [(1<<addr_width)-1:0];
   parameter init = 0;
   parameter memory_file = "vl_ram.vmem";
   generate if (init) begin : init_mem
   initial
     begin
	$readmemh(memory_file, ram);
     end
   end
   endgenerate 
   genvar i;
   generate for (i=0;i<addr_width/4;i=i+1) begin : be_ram
      always @ (posedge clk)
      if (we & be[i])
        ram[adr][(i+1)*8-1:i*8] <= d[(i+1)*8-1:i*8];
   end
   endgenerate
   always @ (posedge clk)
      q <= ram[adr];
endmodule
// Dual port RAM
// ACTEL FPGA should not use logic to handle rw collision
module vl_dpram_1r1w ( d_a, adr_a, we_a, clk_a, q_b, adr_b, clk_b );
   parameter data_width = 32;
   parameter addr_width = 8;
   input [(data_width-1):0]      d_a;
   input [(addr_width-1):0] 	 adr_a;
   input [(addr_width-1):0] 	 adr_b;
   input 			 we_a;
   output [(data_width-1):0] 	 q_b;
   input 			 clk_a, clk_b;
   reg [(addr_width-1):0] 	 adr_b_reg;
   reg [data_width-1:0] ram [(1<<addr_width)-1:0] ;
   parameter init = 0;
   parameter memory_file = "vl_ram.vmem";
   generate if (init) begin : init_mem
   initial
     begin
	$readmemh(memory_file, ram);
     end
   end
   endgenerate 
   always @ (posedge clk_a)
   if (we_a)
     ram[adr_a] <= d_a;
   always @ (posedge clk_b)
   adr_b_reg <= adr_b;   
   assign q_b = ram[adr_b_reg];
endmodule
module vl_dpram_2r1w ( d_a, q_a, adr_a, we_a, clk_a, q_b, adr_b, clk_b );
   parameter data_width = 32;
   parameter addr_width = 8;
   input [(data_width-1):0]      d_a;
   input [(addr_width-1):0] 	 adr_a;
   input [(addr_width-1):0] 	 adr_b;
   input 			 we_a;
   output [(data_width-1):0] 	 q_b;
   output reg [(data_width-1):0] q_a;
   input 			 clk_a, clk_b;
   reg [(data_width-1):0] 	 q_b;   
   reg [data_width-1:0] ram [(1<<addr_width)-1:0] ;
   parameter init = 0;
   parameter memory_file = "vl_ram.vmem";
   generate if (init) begin : init_mem
   initial
     begin
	$readmemh(memory_file, ram);
     end
   end
   endgenerate 
   always @ (posedge clk_a)
     begin 
	q_a <= ram[adr_a];
	if (we_a)
	     ram[adr_a] <= d_a;
     end 
   always @ (posedge clk_b)
	  q_b <= ram[adr_b];
endmodule
module vl_dpram_2r2w ( d_a, q_a, adr_a, we_a, clk_a, d_b, q_b, adr_b, we_b, clk_b );
   parameter data_width = 32;
   parameter addr_width = 8;
   input [(data_width-1):0]      d_a;
   input [(addr_width-1):0] 	 adr_a;
   input [(addr_width-1):0] 	 adr_b;
   input 			 we_a;
   output [(data_width-1):0] 	 q_b;
   input [(data_width-1):0] 	 d_b;
   output reg [(data_width-1):0] q_a;
   input 			 we_b;
   input 			 clk_a, clk_b;
   reg [(data_width-1):0] 	 q_b;   
   reg [data_width-1:0] ram [(1<<addr_width)-1:0] ;
   parameter init = 0;
   parameter memory_file = "vl_ram.vmem";
   generate if (init) begin : init_mem
   initial
     begin
	$readmemh(memory_file, ram);
     end
   end
   endgenerate 
   always @ (posedge clk_a)
     begin 
	q_a <= ram[adr_a];
	if (we_a)
	     ram[adr_a] <= d_a;
     end 
   always @ (posedge clk_b)
     begin 
	q_b <= ram[adr_b];
	if (we_b)
	  ram[adr_b] <= d_b;
     end
endmodule
// Content addresable memory, CAM
// FIFO
module vl_fifo_cmp_async ( wptr, rptr, fifo_empty, fifo_full, wclk, rclk, rst );
   parameter addr_width = 4;   
   parameter N = addr_width-1;
   parameter Q1 = 2'b00;
   parameter Q2 = 2'b01;
   parameter Q3 = 2'b11;
   parameter Q4 = 2'b10;
   parameter going_empty = 1'b0;
   parameter going_full  = 1'b1;
   input [N:0]  wptr, rptr;   
   output 	fifo_empty;
   output       fifo_full;
   input 	wclk, rclk, rst;   
   wire direction;
   reg 	direction_set, direction_clr;
   wire async_empty, async_full;
   wire fifo_full2;
   wire fifo_empty2;   
   // direction_set
   always @ (wptr[N:N-1] or rptr[N:N-1])
     case ({wptr[N:N-1],rptr[N:N-1]})
       {Q1,Q2} : direction_set <= 1'b1;
       {Q2,Q3} : direction_set <= 1'b1;
       {Q3,Q4} : direction_set <= 1'b1;
       {Q4,Q1} : direction_set <= 1'b1;
       default : direction_set <= 1'b0;
     endcase
   // direction_clear
   always @ (wptr[N:N-1] or rptr[N:N-1] or rst)
     if (rst)
       direction_clr <= 1'b1;
     else
       case ({wptr[N:N-1],rptr[N:N-1]})
	 {Q2,Q1} : direction_clr <= 1'b1;
	 {Q3,Q2} : direction_clr <= 1'b1;
	 {Q4,Q3} : direction_clr <= 1'b1;
	 {Q1,Q4} : direction_clr <= 1'b1;
	 default : direction_clr <= 1'b0;
       endcase
    vl_dff_sr dff_sr_dir( .aclr(direction_clr), .aset(direction_set), .clock(1'b1), .data(1'b1), .q(direction));
   assign async_empty = (wptr == rptr) && (direction==going_empty);
   assign async_full  = (wptr == rptr) && (direction==going_full);
    vl_dff_sr dff_sr_empty0( .aclr(rst), .aset(async_full), .clock(wclk), .data(async_full), .q(fifo_full2));
    vl_dff_sr dff_sr_empty1( .aclr(rst), .aset(async_full), .clock(wclk), .data(fifo_full2), .q(fifo_full));
/*
   always @ (posedge wclk or posedge rst or posedge async_full)
     if (rst)
       {fifo_full, fifo_full2} <= 2'b00;
     else if (async_full)
       {fifo_full, fifo_full2} <= 2'b11;
     else
       {fifo_full, fifo_full2} <= {fifo_full2, async_full};
*/
/*   always @ (posedge rclk or posedge async_empty)
     if (async_empty)
       {fifo_empty, fifo_empty2} <= 2'b11;
     else
       {fifo_empty,fifo_empty2} <= {fifo_empty2,async_empty}; */
    vl_dff # ( .reset_value(1'b1)) dff0 ( .d(async_empty), .q(fifo_empty2), .clk(rclk), .rst(async_empty));
    vl_dff # ( .reset_value(1'b1)) dff1 ( .d(fifo_empty2), .q(fifo_empty),  .clk(rclk), .rst(async_empty));
endmodule // async_comp
module vl_fifo_1r1w_async (
    d, wr, fifo_full, wr_clk, wr_rst,
    q, rd, fifo_empty, rd_clk, rd_rst
    );
parameter data_width = 18;
parameter addr_width = 4;
// write side
input  [data_width-1:0] d;
input                   wr;
output                  fifo_full;
input                   wr_clk;
input                   wr_rst;
// read side
output [data_width-1:0] q;
input                   rd;
output                  fifo_empty;
input                   rd_clk;
input                   rd_rst;
wire [addr_width:1] wadr, wadr_bin, radr, radr_bin;
vl_cnt_gray_ce_bin
    # ( .length(addr_width))
    fifo_wr_adr( .cke(wr), .q(wadr), .q_bin(wadr_bin), .rst(wr_rst), .clk(wr_clk));
vl_cnt_gray_ce_bin
    # (.length(addr_width))
    fifo_rd_adr( .cke(rd), .q(radr), .q_bin(radr_bin), .rst(rd_rst), .clk(rd_clk));
vl_dpram_1r1w
    # (.data_width(data_width), .addr_width(addr_width))
    dpram ( .d_a(d), .adr_a(wadr_bin), .we_a(wr), .clk_a(wr_clk), .q_b(q), .adr_b(radr_bin), .clk_b(rd_clk));
vl_fifo_cmp_async
    # (.addr_width(addr_width))
    cmp ( .wptr(wadr), .rptr(radr), .fifo_empty(fifo_empty), .fifo_full(fifo_full), .wclk(wr_clk), .rclk(rd_clk), .rst(wr_rst) );
endmodule
module vl_fifo_2r2w_async (
    // a side
    a_d, a_wr, a_fifo_full,
    a_q, a_rd, a_fifo_empty, 
    a_clk, a_rst,
    // b side
    b_d, b_wr, b_fifo_full,
    b_q, b_rd, b_fifo_empty, 
    b_clk, b_rst	
    );
parameter data_width = 18;
parameter addr_width = 4;
// a side
input  [data_width-1:0] a_d;
input                   a_wr;
output                  a_fifo_full;
output [data_width-1:0] a_q;
input                   a_rd;
output                  a_fifo_empty;
input                   a_clk;
input                   a_rst;
// b side
input  [data_width-1:0] b_d;
input                   b_wr;
output                  b_fifo_full;
output [data_width-1:0] b_q;
input                   b_rd;
output                  b_fifo_empty;
input                   b_clk;
input                   b_rst;
vl_fifo_1r1w_async # (.data_width(data_width), .addr_width(addr_width))
vl_fifo_1r1w_async_a (
    .d(a_d), .wr(a_wr), .fifo_full(a_fifo_full), .wr_clk(a_clk), .wr_rst(a_rst),
    .q(b_q), .rd(b_rd), .fifo_empty(b_fifo_empty), .rd_clk(b_clk), .rd_rst(b_rst)
    );
vl_fifo_1r1w_async # (.data_width(data_width), .addr_width(addr_width))
vl_fifo_1r1w_async_b (
    .d(b_d), .wr(b_wr), .fifo_full(b_fifo_full), .wr_clk(b_clk), .wr_rst(b_rst),
    .q(a_q), .rd(a_rd), .fifo_empty(a_fifo_empty), .rd_clk(a_clk), .rd_rst(a_rst)
    );
endmodule
module vl_fifo_2r2w_async_simplex (
    // a side
    a_d, a_wr, a_fifo_full,
    a_q, a_rd, a_fifo_empty, 
    a_clk, a_rst,
    // b side
    b_d, b_wr, b_fifo_full,
    b_q, b_rd, b_fifo_empty, 
    b_clk, b_rst	
    );
parameter data_width = 18;
parameter addr_width = 4;
// a side
input  [data_width-1:0] a_d;
input                   a_wr;
output                  a_fifo_full;
output [data_width-1:0] a_q;
input                   a_rd;
output                  a_fifo_empty;
input                   a_clk;
input                   a_rst;
// b side
input  [data_width-1:0] b_d;
input                   b_wr;
output                  b_fifo_full;
output [data_width-1:0] b_q;
input                   b_rd;
output                  b_fifo_empty;
input                   b_clk;
input                   b_rst;
// adr_gen
wire [addr_width:1] a_wadr, a_wadr_bin, a_radr, a_radr_bin;
wire [addr_width:1] b_wadr, b_wadr_bin, b_radr, b_radr_bin;
// dpram
wire [addr_width:0] a_dpram_adr, b_dpram_adr;
vl_cnt_gray_ce_bin
    # ( .length(addr_width))
    fifo_a_wr_adr( .cke(a_wr), .q(a_wadr), .q_bin(a_wadr_bin), .rst(a_rst), .clk(a_clk));
vl_cnt_gray_ce_bin
    # (.length(addr_width))
    fifo_a_rd_adr( .cke(a_rd), .q(a_radr), .q_bin(a_radr_bin), .rst(a_rst), .clk(a_clk));
vl_cnt_gray_ce_bin
    # ( .length(addr_width))
    fifo_b_wr_adr( .cke(b_wr), .q(b_wadr), .q_bin(b_wadr_bin), .rst(b_rst), .clk(b_clk));
vl_cnt_gray_ce_bin
    # (.length(addr_width))
    fifo_b_rd_adr( .cke(b_rd), .q(b_radr), .q_bin(b_radr_bin), .rst(b_rst), .clk(b_clk));
// mux read or write adr to DPRAM
assign a_dpram_adr = (a_wr) ? {1'b0,a_wadr_bin} : {1'b1,a_radr_bin};
assign b_dpram_adr = (b_wr) ? {1'b1,b_wadr_bin} : {1'b0,b_radr_bin};
vl_dpram_2r2w
    # (.data_width(data_width), .addr_width(addr_width+1))
    dpram ( .d_a(a_d), .q_a(a_q), .adr_a(a_dpram_adr), .we_a(a_wr), .clk_a(a_clk), 
            .d_b(b_d), .q_b(b_q), .adr_b(b_dpram_adr), .we_b(b_wr), .clk_b(b_clk));
vl_fifo_cmp_async
    # (.addr_width(addr_width))
    cmp1 ( .wptr(a_wadr), .rptr(b_radr), .fifo_empty(b_fifo_empty), .fifo_full(a_fifo_full), .wclk(a_clk), .rclk(b_clk), .rst(a_rst) );
vl_fifo_cmp_async
    # (.addr_width(addr_width))
    cmp2 ( .wptr(b_wadr), .rptr(a_radr), .fifo_empty(a_fifo_empty), .fifo_full(b_fifo_full), .wclk(b_clk), .rclk(a_clk), .rst(b_rst) );
endmodule
//////////////////////////////////////////////////////////////////////
////                                                              ////
////  Versatile library, wishbone stuff                           ////
////                                                              ////
////  Description                                                 ////
////  Wishbone compliant modules                                  ////
////                                                              ////
////                                                              ////
////  To Do:                                                      ////
////   -                                                          ////
////                                                              ////
////  Author(s):                                                  ////
////      - Michael Unneback, unneback@opencores.org              ////
////        ORSoC AB                                              ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2010 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// 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. ////
////                                                              ////
//// This source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
// async wb3 - wb3 bridge
`timescale 1ns/1ns
module vl_wb3wb3_bridge ( 
	// wishbone slave side
	wbs_dat_i, wbs_adr_i, wbs_sel_i, wbs_bte_i, wbs_cti_i, wbs_we_i, wbs_cyc_i, wbs_stb_i, wbs_dat_o, wbs_ack_o, wbs_clk, wbs_rst,
	// wishbone master side
	wbm_dat_o, wbm_adr_o, wbm_sel_o, wbm_bte_o, wbm_cti_o, wbm_we_o, wbm_cyc_o, wbm_stb_o, wbm_dat_i, wbm_ack_i, wbm_clk, wbm_rst);
input [31:0] wbs_dat_i;
input [31:2] wbs_adr_i;
input [3:0]  wbs_sel_i;
input [1:0]  wbs_bte_i;
input [2:0]  wbs_cti_i;
input wbs_we_i, wbs_cyc_i, wbs_stb_i;
output [31:0] wbs_dat_o;
output wbs_ack_o;
input wbs_clk, wbs_rst;
output [31:0] wbm_dat_o;
output reg [31:2] wbm_adr_o;
output [3:0]  wbm_sel_o;
output reg [1:0]  wbm_bte_o;
output reg [2:0]  wbm_cti_o;
output reg wbm_we_o;
output wbm_cyc_o;
output wbm_stb_o;
input [31:0]  wbm_dat_i;
input wbm_ack_i;
input wbm_clk, wbm_rst;
parameter addr_width = 4;
// bte
parameter linear       = 2'b00;
parameter wrap4        = 2'b01;
parameter wrap8        = 2'b10;
parameter wrap16       = 2'b11;
// cti
parameter classic      = 3'b000;
parameter incburst     = 3'b010;
parameter endofburst   = 3'b111;
parameter wbs_adr  = 1'b0;
parameter wbs_data = 1'b1;
parameter wbm_adr0 = 2'b00;
parameter wbm_adr1 = 2'b01;
parameter wbm_data = 2'b10;
reg [1:0] wbs_bte_reg;
reg wbs;
wire wbs_eoc_alert, wbm_eoc_alert;
reg wbs_eoc, wbm_eoc;
reg [1:0] wbm;
wire [1:16] wbs_count, wbm_count;
wire [35:0] a_d, a_q, b_d, b_q;
wire a_wr, a_rd, a_fifo_full, a_fifo_empty, b_wr, b_rd, b_fifo_full, b_fifo_empty;
reg a_rd_reg;
wire b_rd_adr, b_rd_data;
wire b_rd_data_reg;
wire [35:0] temp;
assign wbs_eoc_alert = (wbs_bte_reg==wrap4 & wbs_count[3]) | (wbs_bte_reg==wrap8 & wbs_count[7]) | (wbs_bte_reg==wrap16 & wbs_count[15]);
always @ (posedge wbs_clk or posedge wbs_rst)
if (wbs_rst)
	wbs_eoc <= 1'b0;
else
	if (wbs==wbs_adr & wbs_stb_i & !a_fifo_full)
		wbs_eoc <= wbs_bte_i==linear;
	else if (wbs_eoc_alert & (a_rd | a_wr))
		wbs_eoc <= 1'b1;
vl_cnt_shreg_ce_clear # ( .length(16))
    cnt0 (
        .cke(wbs_ack_o),
        .clear(wbs_eoc),
        .q(wbs_count),
        .rst(wbs_rst),
        .clk(wbs_clk));
always @ (posedge wbs_clk or posedge wbs_rst)
if (wbs_rst)
	wbs <= wbs_adr;
else
	if ((wbs==wbs_adr) & wbs_cyc_i & wbs_stb_i & !a_fifo_full)
		wbs <= wbs_data;
	else if (wbs_eoc & wbs_ack_o)
		wbs <= wbs_adr;
// wbs FIFO
assign a_d = (wbs==wbs_adr) ? {wbs_adr_i[31:2],wbs_we_i,wbs_bte_i,wbs_cti_i} : {wbs_dat_i,wbs_sel_i};
assign a_wr = (wbs==wbs_adr)  ? wbs_cyc_i & wbs_stb_i & !a_fifo_full :
              (wbs==wbs_data) ? wbs_we_i  & wbs_stb_i & !a_fifo_full :
              1'b0;
assign a_rd = !a_fifo_empty;
always @ (posedge wbs_clk or posedge wbs_rst)
if (wbs_rst)
	a_rd_reg <= 1'b0;
else
	a_rd_reg <= a_rd;
assign wbs_ack_o = a_rd_reg | (a_wr & wbs==wbs_data);
assign wbs_dat_o = a_q[35:4];
always @ (posedge wbs_clk or posedge wbs_rst)
if (wbs_rst)
	wbs_bte_reg <= 2'b00;
else
	wbs_bte_reg <= wbs_bte_i;
// wbm FIFO
assign wbm_eoc_alert = (wbm_bte_o==wrap4 & wbm_count[3]) | (wbm_bte_o==wrap8 & wbm_count[7]) | (wbm_bte_o==wrap16 & wbm_count[15]);
always @ (posedge wbm_clk or posedge wbm_rst)
if (wbm_rst)
	wbm_eoc <= 1'b0;
else
	if (wbm==wbm_adr0 & !b_fifo_empty)
		wbm_eoc <= b_q[4:3] == linear;
	else if (wbm_eoc_alert & wbm_ack_i)
		wbm_eoc <= 1'b1;
always @ (posedge wbm_clk or posedge wbm_rst)
if (wbm_rst)
	wbm <= wbm_adr0;
else
    if ((wbm==wbm_adr0 & !b_fifo_empty) |
        (wbm==wbm_adr1 & !b_fifo_empty & wbm_we_o) |
        (wbm==wbm_adr1 & !wbm_we_o) |
        (wbm==wbm_data & wbm_ack_i & wbm_eoc))
        wbm <= {wbm[0],!(wbm[1] ^ wbm[0])};  // count sequence 00,01,10
assign b_d = {wbm_dat_i,4'b1111};
assign b_wr = !wbm_we_o & wbm_ack_i;
assign b_rd_adr  = (wbm==wbm_adr0 & !b_fifo_empty);
assign b_rd_data = (wbm==wbm_adr1 & !b_fifo_empty & wbm_we_o) ? 1'b1 : // b_q[`WE]
                   (wbm==wbm_data & !b_fifo_empty & wbm_we_o & wbm_ack_i & !wbm_eoc) ? 1'b1 :
                   1'b0;
assign b_rd = b_rd_adr | b_rd_data;
vl_dff dff1 ( .d(b_rd_data), .q(b_rd_data_reg), .clk(wbm_clk), .rst(wbm_rst));
vl_dff_ce # ( .width(36)) dff2 ( .d(b_q), .ce(b_rd_data_reg), .q(temp), .clk(wbm_clk), .rst(wbm_rst));
assign {wbm_dat_o,wbm_sel_o} = (b_rd_data_reg) ? b_q : temp;
vl_cnt_shreg_ce_clear # ( .length(16))
    cnt1 (
        .cke(wbm_ack_i),
        .clear(wbm_eoc),
        .q(wbm_count),
        .rst(wbm_rst),
        .clk(wbm_clk));
assign wbm_cyc_o = wbm==wbm_data;
assign wbm_stb_o = (wbm==wbm_data & wbm_we_o) ? !b_fifo_empty : 
                   (wbm==wbm_data) ? 1'b1 :
                   1'b0;
always @ (posedge wbm_clk or posedge wbm_rst)
if (wbm_rst)
	{wbm_adr_o,wbm_we_o,wbm_bte_o,wbm_cti_o} <= {30'h0,1'b0,linear,classic};
else begin
	if (wbm==wbm_adr0 & !b_fifo_empty)
		{wbm_adr_o,wbm_we_o,wbm_bte_o,wbm_cti_o} <= b_q;
	else if (wbm_eoc_alert & wbm_ack_i)
		wbm_cti_o <= endofburst;
end	
//async_fifo_dw_simplex_top
vl_fifo_2r2w_async_simplex
# ( .data_width(36), .addr_width(addr_width))
fifo (
    // a side
    .a_d(a_d), 
    .a_wr(a_wr), 
    .a_fifo_full(a_fifo_full),
    .a_q(a_q),
    .a_rd(a_rd),
    .a_fifo_empty(a_fifo_empty), 
    .a_clk(wbs_clk), 
    .a_rst(wbs_rst),
    // b side
    .b_d(b_d), 
    .b_wr(b_wr), 
    .b_fifo_full(b_fifo_full),
    .b_q(b_q), 
    .b_rd(b_rd), 
    .b_fifo_empty(b_fifo_empty), 
    .b_clk(wbm_clk), 
    .b_rst(wbm_rst)	
    );
endmodule
// WB ROM
module vl_wb_boot_rom (
    wb_adr_i, wb_stb_i, wb_cyc_i, 
    wb_dat_o, wb_ack_o, hit_o, wb_clk, wb_rst);
    parameter adr_hi = 31;
    parameter adr_lo = 28;
    parameter adr_sel = 4'hf;
    parameter addr_width = 5;
//E2_ifndef BOOT_ROM
//E2_define BOOT_ROM "boot_rom.v"
//E2_endif
    input [adr_hi:2]    wb_adr_i;
    input 		wb_stb_i;
    input 		wb_cyc_i;
    output [31:0] 	wb_dat_o;
    output  		wb_ack_o;
    output              hit_o;
    input 		wb_clk;
    input 		wb_rst;
    wire hit;
    reg [31:0] wb_dat;
    reg wb_ack;
assign hit = wb_adr_i[adr_hi:adr_lo] == adr_sel;
always @ (posedge wb_clk or posedge wb_rst)
    if (wb_rst)
        wb_dat <= 32'h15000000;
    else
	 case (wb_adr_i[addr_width-1:2])
//E2_include `BOOT_ROM
	   /*	 
	    // Zero r0 and jump to 0x00000100
	    0 : wb_dat <= 32'h18000000;
	    1 : wb_dat <= 32'hA8200000;
	    2 : wb_dat <= 32'hA8C00100;
	    3 : wb_dat <= 32'h44003000;
	    4 : wb_dat <= 32'h15000000;
	    */
	   default:
	     wb_dat <= 32'h00000000;
	 endcase // case (wb_adr_i)
always @ (posedge wb_clk or posedge wb_rst)
    if (wb_rst)
        wb_ack <= 1'b0;
    else
        wb_ack <= wb_stb_i & wb_cyc_i & hit & !wb_ack;
assign hit_o = hit;
assign wb_dat_o = wb_dat & {32{wb_ack}};
assign wb_ack_o = wb_ack;
endmodule
//////////////////////////////////////////////////////////////////////
////                                                              ////
////  Arithmetic functions                                        ////
////                                                              ////
////  Description                                                 ////
////  Arithmetic functions for ALU and DSP                        ////
////                                                              ////
////                                                              ////
////  To Do:                                                      ////
////   -                                                          ////
////                                                              ////
////  Author(s):                                                  ////
////      - Michael Unneback, unneback@opencores.org              ////
////        ORSoC AB                                              ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2010 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// 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. ////
////                                                              ////
//// This source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
// signed multiplication
module vl_mults (a,b,p);
parameter operand_a_width = 18;
parameter operand_b_width = 18;
parameter result_hi = 35;
parameter result_lo = 0;
input [operand_a_width-1:0] a;
input [operand_b_width-1:0] b;
output [result_hi:result_lo] p;
wire signed [operand_a_width-1:0] ai;
wire signed [operand_b_width-1:0] bi;
wire signed [operand_a_width+operand_b_width-1:0] result;
    assign ai = a;
    assign bi = b;
    assign result = ai * bi;
    assign p = result[result_hi:result_lo];
endmodule
module vl_mults18x18 (a,b,p);
input [17:0] a,b;
output [35:0] p;
vl_mult
    # (.operand_a_width(18), .operand_b_width(18))
    mult0 (.a(a), .b(b), .p(p));
endmodule
// unsigned multiplication
module vl_mult (a,b,p);
parameter operand_a_width = 18;
parameter operand_b_width = 18;
parameter result_hi = 35;
parameter result_lo = 0;
input [operand_a_width-1:0] a;
input [operand_b_width-1:0] b;
output [result_hi:result_hi] p;
wire [operand_a_width+operand_b_width-1:0] result;
    assign result = a * b;
    assign p = result[result_hi:result_lo];
endmodule
// shift unit
// supporting the following shift functions
//   SLL
//   SRL
//   SRA
module vl_shift_unit_32( din, s, dout, opcode);
input [31:0] din; // data in operand
input [4:0] s; // shift operand
input [1:0] opcode;
output [31:0] dout;
parameter opcode_sll = 2'b00;
//parameter opcode_srl = 2'b01;
parameter opcode_sra = 2'b10;
//parameter opcode_ror = 2'b11;
wire sll, sra;
assign sll = opcode == opcode_sll;
assign sra = opcode == opcode_sra;
wire [15:1] s1;
wire [3:0] sign;
wire [7:0] tmp [0:3];
// first stage is multiplier based
// shift operand as fractional 8.7
assign s1[15] = sll & s[2:0]==3'd7;
assign s1[14] = sll & s[2:0]==3'd6;
assign s1[13] = sll & s[2:0]==3'd5;
assign s1[12] = sll & s[2:0]==3'd4;
assign s1[11] = sll & s[2:0]==3'd3;
assign s1[10] = sll & s[2:0]==3'd2;
assign s1[ 9] = sll & s[2:0]==3'd1;
assign s1[ 8] = s[2:0]==3'd0;
assign s1[ 7] = !sll & s[2:0]==3'd1;
assign s1[ 6] = !sll & s[2:0]==3'd2;
assign s1[ 5] = !sll & s[2:0]==3'd3;
assign s1[ 4] = !sll & s[2:0]==3'd4;
assign s1[ 3] = !sll & s[2:0]==3'd5;
assign s1[ 2] = !sll & s[2:0]==3'd6;
assign s1[ 1] = !sll & s[2:0]==3'd7;
assign sign[3] = din[31] & sra;
assign sign[2] = sign[3] & (&din[31:24]);
assign sign[1] = sign[2] & (&din[23:16]);
assign sign[0] = sign[1] & (&din[15:8]);
vl_mults # ( .operand_a_width(25), .operand_b_width(16), .result_hi(14), .result_lo(7)) mult_byte3 ( .a({sign[3], {8{sign[3]}},din[31:24], din[23:16]}), .b({1'b0,s1}), .p(tmp[3]));
vl_mults # ( .operand_a_width(25), .operand_b_width(16), .result_hi(14), .result_lo(7)) mult_byte2 ( .a({sign[2], din[31:24]  ,din[23:16],  din[15:8]}), .b({1'b0,s1}), .p(tmp[2]));
vl_mults # ( .operand_a_width(25), .operand_b_width(16), .result_hi(14), .result_lo(7)) mult_byte1 ( .a({sign[1], din[23:16]  ,din[15:8],   din[7:0]}), .b({1'b0,s1}), .p(tmp[1]));
vl_mults # ( .operand_a_width(25), .operand_b_width(16), .result_hi(14), .result_lo(7)) mult_byte0 ( .a({sign[0], din[15:8]   ,din[7:0],    8'h00}),      .b({1'b0,s1}), .p(tmp[0]));
// second stage is multiplexer based
// shift on byte level
// mux byte 3
assign dout[31:24] = (s[4:3]==2'b00) ? tmp[3] :
                     (sll & s[4:3]==2'b01) ? tmp[2] :
                     (sll & s[4:3]==2'b10) ? tmp[1] :
                     (sll & s[4:3]==2'b11) ? tmp[0] :
                     {8{sign[3]}};
// mux byte 2
assign dout[23:16] = (s[4:3]==2'b00) ? tmp[2] :
                     (sll & s[4:3]==2'b01) ? tmp[1] :
                     (sll & s[4:3]==2'b10) ? tmp[0] :
                     (sll & s[4:3]==2'b11) ? {8{1'b0}} :
                     (s[4:3]==2'b01) ? tmp[3] :
                     {8{sign[3]}};
// mux byte 1
assign dout[15:8]  = (s[4:3]==2'b00) ? tmp[1] :
                     (sll & s[4:3]==2'b01) ? tmp[0] :
                     (sll & s[4:3]==2'b10) ? {8{1'b0}} :
                     (sll & s[4:3]==2'b11) ? {8{1'b0}} :
                     (s[4:3]==2'b01) ? tmp[2] :
                     (s[4:3]==2'b10) ? tmp[3] :
                     {8{sign[3]}};
// mux byte 0
assign dout[7:0]   = (s[4:3]==2'b00) ? tmp[0] :
                     (sll) ?  {8{1'b0}}:
                     (s[4:3]==2'b01) ? tmp[1] :
                     (s[4:3]==2'b10) ? tmp[2] :
                     tmp[3];
endmodule
// logic unit
// supporting the following logic functions
//    a and b
//    a or  b
//    a xor b
//    not b
module vl_logic_unit( a, b, result, opcode);
parameter width = 32;
parameter opcode_and = 2'b00;
parameter opcode_or  = 2'b01;
parameter opcode_xor = 2'b10;
input [width-1:0] a,b;
output [width-1:0] result;
input [1:0] opcode;
assign result = (opcode==opcode_and) ? a & b :
                (opcode==opcode_or)  ? a | b :
                (opcode==opcode_xor) ? a ^ b :
                b;
endmodule
module vl_arith_unit ( a, b, c_in, add_sub, sign, result, c_out, z, ovfl);
parameter width = 32;
parameter opcode_add = 1'b0;
parameter opcode_sub = 1'b1;
input [width-1:0] a,b;
input c_in, add_sub, sign;
output [width-1:0] result;
output c_out, z, ovfl;
assign {c_out,result} = {(a[width-1] & sign),a} + ({a[width-1] & sign,b} ^ {(width+1){(add_sub==opcode_sub)}}) + {{(width-1){1'b0}},(c_in | (add_sub==opcode_sub))};
assign z = (result=={width{1'b0}});
assign ovfl = ( a[width-1] &  b[width-1] & ~result[width-1]) |
               (~a[width-1] & ~b[width-1] &  result[width-1]);
endmodule
 

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