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How to use Perl in your Verilog HDL Design Flow?
Anyone who designs with Verilog HDL has probably grown tired of generating module instantiations in a hierarchical design, or creating a new top level or lower level Verilog HDL module. I have generated a few Perl Scripts that will automatically generate the module instantiations, top level module, and lower level module for you. These Perl Scripts can be invoked from within VI/VIM/GVIM, or a DOS Command Window. If you invoke them from within VI, the script output will be printed in the current file. If you invoke them from within a DOS Command Window, then you will have to either cut and paste into your Verilog HDL file or pipe the output to a new file. Below are the scripts:
The scripts above have been modified to use a Perl Module named VerilogTools, which can be downloaded [here]. Simply unzip the file 'tar -xzvf verilog_pkg.tgz' in a temporary directory and execute the following commands:
  1. perl Makefile.PL
  2. make
  3. make install

How to use vertools.pl?
This utility is a combination of ver_mod_top.pl, ver_mod_low.pl, ver_inst.pl, ver_tb.pl, and ver_ucf.pl. This script implements the following functions:
        Usage: vertools.pl [-h] [-v] [-i|-t|-u|-a|-z] [-f ]

                -h              Print this help message.
                -v              Verbose: Print Debug Information.
                -i              Generate Verilog HDL Instantiation.
                -t              Generate Verilog HDL Test Bench.
                -u              Generate UCF file from Verilog HDL file.
                -a              Generate new Verilog HDL top-level module file from Template.
                -z              Generate new Verilog HDL low-level module file from Template.
                -f        Verilog HDL input file.

                Example of Module Instantiation:
                        vertools.pl -i -f sample.v
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How to use ver_mod_top.pl?
This utility is intended to make creating new Verilog HDL modules easier using a good editor, such as VI. As long as you set the top line to correctly point to your perl binary, and place this script in a directory in your path, you can invoke it from VI. Simply use the !! command and call this script with the filename you wish to instantiate. This script will create a new text file called "new_module_name.v" when you type the following command:
        !! ver_mod_top.pl -a -f new_module_name.v
The script will generate the empty Verilog HDL template for you in the file "new_module_name.v". Note: "new_module_name.v" is the name of the new Verilog HDL file and can be anything you like. The module declaration uses Verilog 2001 ANSI-C style. You can either use VI or a DOS Command prompt to run this script. If you want to use a DOS Command prompt, then see the instructions below:
  1. Change directory to the desired directory
    • cd C:\design\new_module
    • If the directory "new_module" does not exist type: mkdir C:\design\new_module, before changing directory.
  2. Type the following: perl ver_mod_top.pl -a -f new_module_name.v
  3. When the script is finished you will see the message: "The script has finished successfully! You can now use new_module_name.v."
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How to use ver_mod_low.pl?
This utility is intended to make creating new Verilog HDL modules easier using a good editor, such as VI. As long as you set the top line to correctly point to your perl binary, and place this script in a directory in your path, you can invoke it from VI. Simply use the !! command and call this script with the filename you wish to instantiate. This script will create a new text file called "new_module_name.v" when you type the following command:
	!! ver_mod_low.pl -z -f new_module_name.v
The script will generate the empty Verilog HDL template for you in the file "new_module_name.v". Note: "new_module_name.v" is the name of the new Verilog HDL file and can be anything you like. The module declaration uses Verilog 2001 ANSI-C style. You can either use VI or a DOS Command prompt to run this script. If you want to use a DOS Command prompt, then see the instructions below:
  1. Change directory to the desired directory
    • cd C:\design\new_module
    • If the directory "new_module" does not exist type: mkdir C:\design\new_module, before changing directory.
  2. Type the following: perl ver_mod_top.pl -z -f new_module_name.v
  3. When the script is finished you will see the message: "The script has finished successfully! You can now use new_module_name.v."
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How to use ver_inst.pl?
This utility is intended to make instantiation in verilog easier using a good editor, such as VI. As long as you set the top line to correctly point to your perl binary, and place this script in a directory in your path, you can invoke it from VI. Simply use the !! command and call this script with the filename you wish to instantiate.
	!! ver_inst.pl -i -f adder.v
The script will retrieve the module definition from the file you specify and provide the instantiation for you in the current file at the cursor position.
For instance, if adder.v contains the following definition:
        module adder (input wire a, 
                      input wire b, 
                      output reg sum, 
                      output reg carry);
Then this is what the script will insert in your editor for you:
	adder adder (
		.a (a),
		.b (b),
		.sum (sum),
		.carry (carry) 
	        );
The keyword "module" must be left justified in the verilog file you are instantiating to work.
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How to use ver_tb.pl?
This utility is intended to make creating new Verilog HDL Test Bench modules easier using a good editor, such as VI. As long as you set the top line to correctly point to your perl binary, and place this script in a directory in your path, you can invoke it from VI. Simply use the !! command and call this script with the filename you wish to instantiate. This script will create a new text file called "tb_module_name.v" when you type the following command:
        !! ver_tb.pl -t -f module_name.v
The script will generate the Verilog HDL test bench template for you with the port contents of "module_name.v". Note: "module_name.v" is the name of the existing Verilog HDL file, and "tb_module_name.v" is the new test bench file.
The script will retrieve the module definition from the "module_name.v" file you specify and provide the instantiation for you in the new "tb_module_name.v" file.
The keyword "module" must be left justified in the verilog file you are instantiating to work.
You can either use VI or a DOS Command prompt to run this script. If you want to use a DOS Command prompt, then see the instructions below:
  1. Change directory to the desired directory
    • cd C:\design\module
  2. Type the following: perl ver_tb.pl -t -f module_name.v
  3. When the script is finished you will see the message: "The script has finished successfully! You can now use tb_new_module_name.v."
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How to use ver_ucf.pl?

This utility is intended to make the creation of UCF files for Xilinx designs easier.
As long as you set the top line to correctly point to your perl binary, and place this script in a directory in your path, you can invoke it from VI. Simply use the !! command and call this script with the filename you wish to generate a UCF from.
	!! ver_ucf -u -f adder.v
The script will retrieve the input/inout/output definitions from the file you specify and reformat it into the UCF format. It will then write a new file called "adder.ucf", which contains the pin assignments. Below is an example of the UCF file contents:
                                                                              
#*****************************************************************
#
# adder.ucf module
#
#*****************************************************************
#
# UC Davis Confidential Copyright  2009 ECE Department
#
#*****************************************************************
#
# created on:	05/02/2009
# created by:	Jeremy W. Webb
# last edit on:	05/02/2009
# last edit by:	Jeremy W. Webb
# revision:	001
# comments:	Generated.
#
# board name:		My Board
# board number:		xxx
# board revision:	A
# device mpn:		XC3Sxxx-4VQ100C
# 
#******************************************************************
#
#--------------------------------------
# T I M I N G   C O N S T R A I N T S
#--------------------------------------
# N/A

#--------------------------------------
# P I N   A S S I G N M E N T S 
#--------------------------------------
NET "FPGA_10MHz" LOC = "" | IOSTANDARD = LVCMOS33;
NET "FPGA_INT_SWP" LOC = "" | IOSTANDARD = LVCMOS33;
NET "FPGA_ID"  LOC = "" | IOSTANDARD = LVCMOS33;                          
The pin numbers are left blank for you to fill in with the correct values.
You can either use VI or a DOS Command prompt to run this script. If you want to use a DOS Command prompt, then see the instructions below:
  1. Change directory to the desired directory
    • cd C:\design\
  2. Type the following: perl ver_ucf.pl -u -f module_name.v
  3. When the script is finished you will see the message: "The script has finished successfully! You can now use module_name.ucf."
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How to use coe_dec2hex.pl?
This utility is intended to convert a Xilinx Coefficient File (.COE) to a Xilinx Memory Initialization File (.MIF) file. This script basically converts base 10 integers to hexadecimal values. This script defaults to 18-bit resolution for the dec2hex conversion. This script will create a new text file called "file.mif" when you type the following command at a shell prompt:
        coe_dec2hex.pl FILENAME RESOLUTION
The options are described below:

FILENAME: Where FILE is the Xilinx Coefficient File (*.coe) containing base-10 numbers.
RESOLUTION: Hexadecimal Resolution in bits. For example, 18. DEFAULT: 18
This Perl script requires the Perl package: Toolbox::Simple..
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How to use mif_hex2dec.pl?
This utility is intended to convert a Xilinx Memory Initialization File (.MIF) to a Xilinx Coefficient File (.COE) file. This script basically converts base 2 hexadecimal values to base 10 integers. This script defaults to 18-bit resolution for the hexadecimal-to-decimal conversion. This script is invoked by typing the following command:
	mif_hex2dec.pl FILENAME RESOLUTION
The options are described below:

FILENAME: Where FILE is the Xilinx Memory Initialization File (*.mif) containing base-2 numbers.
RESOLUTION: Hexadecimal Resolution in bits. For example, 18. DEFAULT: 18
This Perl script requires the Perl package: Toolbox::Simple..
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Jeremy W. Webb
Graduate Student
Electrical and Computer Engineering Department
One Shields Avenue
Davis, CA 95616