1CodeGen(3) User Contributed Perl Documentation CodeGen(3)
2
3
4
6 Verilog::CodeGen - Verilog code generator
7
9 use Verilog::CodeGen;
10
11 mkdir 'DeviceLibs/Objects/YourDesign', 0755;
12 chdir 'DeviceLibs/Objects/YourDesign';
13
14 # if the directory YourDesign exists, the second argument can be omitted
15 # create YourModule.pl in YourDesign
16 &create_template_file('YourModule','YourDesign');
17
18 # create a device library for testing in DeviceLibs/Objects/DeviceLibs
19 &make_module('YourModule','YourDesign');
20
21 # create the final device library in DeviceLibs (once YourModule code is clean)
22 &make_module('','YourDesign');
23
25 The most efficient way to use the code generator is using the GUI
26 ("gui.pl" in scripts in the distribution). Read the documentation in
27 Verilog::CodeGen::Gui.pm). Alternatively, you can use the scripts that
28 the GUI uses to do the work (in the scripts/GUI folder). If you want to
29 make your own, follow the SYNOPSIS.
30
31 Then edit the file YourModule.pl in the folder
32 DeviceLibs/Objects/YourDesign.
33
34 For example:
35
36 sub gen_YourModule {
37 my $objref=shift;
38 my $par=$objref->{parname}||1;
39
40 # Create Objects
41
42 my $submodule=new('SubModule',parname1=>$par);
43
44 # Instantiate
45
46 my $pins="(A,Z)";
47 my $modname=$objref->{modulename};
48 my $code = "
49 module $modname $pins;
50 input A;
51 output Z;
52 ";
53 $code.=$submodule->inst('suffix',P1=>'A');
54 $code .="
55 endmodule // $modname
56 ";
57 $objref->{pins}=$pins;
58 return $code;
59 } # END of gen_YourModule
60
61 Then run "perl YourModule.pl" to check if the code produces valid a
62 Verilog module.
63
64 If this is the case, add YourModule to the device library with
65 "&make_module()"
66
67 Next, create a testbench test_YourModule.pl in a directory on the same
68 level as DeviceLibs (TestObj if you use the GUI):
69
70 use lib '..';
71 use DeviceLibs::YourDesign;
72
73 my $device=new("S_buffer_demux",depth=>7,);
74
75 open (VER,">test_S_buffer_demux.v");
76
77 output(*VER);
78
79 modules();
80
81 print VER "
82 module test_S_buffer_demux;
83 wire A;
84 wire [7:0] S;
85 wire [6:0] Z;
86 wire D;
87
88 reg a;
89 reg [7:0] s;
90
91 assign A= a;
92 assign S= s;
93
94 reg _ck;
95 ";
96 $device->instance();
97 my $x=$device->{""};
98
99 print VER "
100 // clock generator
101 always begin: clock_wave
102 #10 _ck = 0;
103 #10 _ck = 1;
104
105 end
106
107 always @(posedge _ck)
108 begin
109 \$display(\" \%0d \%b \%b \",\$time,$x. Z,$x. D);
110 end
111
112 initial
113 begin
114 \$display(\"Time Z D\");
115 a<=1;
116 #25;
117 a<=0;
118 #25;
119 \$finish;
120 end
121 endmodule
122 ";
123 close VER;
124 run("test_S_buffer_demux.v");
125 #plot("test_S_buffer_demux.v");
126
127 Execute the testbench script with "perl test_YourModule.pl".
128
130 Provides an object-oriented environment to generate Verilog code for
131 modules and testbenches. The Verilog::CodeGen module provides two
132 functions, one to create a code template and another to create a Perl
133 module which contains the device library. This module ,
134 DeviceLibs::YourDesign, provides the class methods and contains the
135 objects for every Verilog module; the objects are created based on a
136 fixed template. The purpose of this module is to allow the generation
137 of customized Verilog modules. A Verilog module can have a large number
138 of parameters like input and output bus width, buffer depth, signal
139 delay etc. The code generator allows to create an object that will
140 generate the Verilog module code for arbitraty values of the
141 parameters.
142
144 With the Perl module distribution come a number of utility scripts. The
145 most important one is gui.pl, a GUI frontend for Verilog development
146 using the code generator.
147
149 new($object_name[,%attributes]);
150 Create a new Verilog module object. The object attributes are optional,
151 the object should provide reasonable defaults.
152
153 output([*filehandle_ref||$filename])
154 output() takes a reference to a filehandle or a filename as argument.
155 These are stored in the global %printcfg. Without arguments, this
156 defaults to STDOUT. If output() is called with as argument a string
157 containing \n and/or \s, this string is printed on the current
158 filehandle.
159
160 modules
161 The code generator stores all submodules of a given module in the
162 global %modules. Calling modules() prints the code for these modules on
163 the current filehandle.
164
165 instance([$instance_suffix,%connectivity])
166 The instance() method will print the code for the instantiation of the
167 object on the current filehandle. An optional instance suffix can be
168 specified (to distinguish between different instances of the same
169 module), as well as the pin connectivity. If the connectivity for a pin
170 is not specified, it defaults to the pin name.
171
172 inst([$instance_suffix,%connectivity])
173 The inst() method will return the code for the instantiation of the
174 object as a string. An optional instance suffix can be specified (to
175 distinguish between different instances of the same module), as well as
176 the pin connectivity. If the connectivity for a pin is not specified,
177 it defaults to the pin name.
178
179 run([$filename])
180 Run the netlist through the Icarus Verilog (http://www.icarus.com) open
181 source verilog simulator. The filename is optional if it was specified
182 with the output() method.
183
184 plot([$filename])
185 Plot the result of the simulation with gtkwave. For this purpose, the
186 \$dumpvar and \$dumpfile compiler directives must be present in the
187 testbench code. The filename is optional if it was specified with the
188 output() method.
189
190 module('modulename')
191 This method can be used to print the code for a specified module on the
192 current filehandle.
193
194 search(/pattern/)
195 Search the verilog code for a given pattern.
196
197 find_inst(/pattern/)
198 Find all instances matching /pattern/ in the netlist.
199
201 {$instance_suffix}
202 Returns the full instance name of the object.
203 $x=$object->{$instance_suffix};
204
206 · Convert the utility scripts to functions to be called from
207 Verilog::CodeGen.
208
209 · Put the GUI scripts in a module Gui.pm.
210
211 · Separate the code for testing purposes from the module object code.
212
214 Icarus Verilog <http://icarus.com/eda/verilog/index.html>
215
217 W. Vanderbauwhede wim@motherearth.org.
218
219 <http://www.comms.eee.strath.ac.uk/~wim>
220
222 Copyright (c) 2002 Wim Vanderbauwhede. All rights reserved. This
223 program is free software; you can redistribute it and/or modify it
224 under the same terms as Perl itself.
225
226
227
228perl v5.30.1 2020-01-30 CodeGen(3)